xref: /llvm-project/llvm/unittests/Support/VirtualFileSystemTest.cpp (revision edd7fed9da48c0e708cce9bd4d305ae43d8bd77c)
1 //===- unittests/Support/VirtualFileSystem.cpp -------------- VFS tests ---===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/Support/VirtualFileSystem.h"
10 #include "llvm/ADT/IntrusiveRefCntPtr.h"
11 #include "llvm/ADT/ScopeExit.h"
12 #include "llvm/Config/llvm-config.h"
13 #include "llvm/Support/Errc.h"
14 #include "llvm/Support/FileSystem.h"
15 #include "llvm/Support/MemoryBuffer.h"
16 #include "llvm/Support/Path.h"
17 #include "llvm/Support/SourceMgr.h"
18 #include "llvm/TargetParser/Host.h"
19 #include "llvm/TargetParser/Triple.h"
20 #include "llvm/Testing/Support/SupportHelpers.h"
21 #include "gmock/gmock.h"
22 #include "gtest/gtest.h"
23 #include <map>
24 #include <string>
25 
26 using namespace llvm;
27 using llvm::sys::fs::UniqueID;
28 using llvm::unittest::TempDir;
29 using llvm::unittest::TempFile;
30 using llvm::unittest::TempLink;
31 using testing::ElementsAre;
32 using testing::Pair;
33 using testing::UnorderedElementsAre;
34 
35 namespace {
36 struct DummyFile : public vfs::File {
37   vfs::Status S;
38   explicit DummyFile(vfs::Status S) : S(S) {}
39   llvm::ErrorOr<vfs::Status> status() override { return S; }
40   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
41   getBuffer(const Twine &Name, int64_t FileSize, bool RequiresNullTerminator,
42             bool IsVolatile) override {
43     llvm_unreachable("unimplemented");
44   }
45   std::error_code close() override { return std::error_code(); }
46 };
47 
48 class DummyFileSystem : public vfs::FileSystem {
49   int FSID;   // used to produce UniqueIDs
50   int FileID; // used to produce UniqueIDs
51   std::string WorkingDirectory;
52   std::map<std::string, vfs::Status> FilesAndDirs;
53   typedef std::map<std::string, vfs::Status>::const_iterator const_iterator;
54 
55   static int getNextFSID() {
56     static int Count = 0;
57     return Count++;
58   }
59 
60 public:
61   DummyFileSystem() : FSID(getNextFSID()), FileID(0) {}
62 
63   ErrorOr<vfs::Status> status(const Twine &Path) override {
64     auto I = findEntry(Path);
65     if (I == FilesAndDirs.end())
66       return make_error_code(llvm::errc::no_such_file_or_directory);
67     return I->second;
68   }
69   ErrorOr<std::unique_ptr<vfs::File>>
70   openFileForRead(const Twine &Path) override {
71     auto S = status(Path);
72     if (S)
73       return std::unique_ptr<vfs::File>(new DummyFile{*S});
74     return S.getError();
75   }
76   llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override {
77     return WorkingDirectory;
78   }
79   std::error_code setCurrentWorkingDirectory(const Twine &Path) override {
80     WorkingDirectory = Path.str();
81     return std::error_code();
82   }
83   // Map any symlink to "/symlink".
84   std::error_code getRealPath(const Twine &Path,
85                               SmallVectorImpl<char> &Output) override {
86     auto I = findEntry(Path);
87     if (I == FilesAndDirs.end())
88       return make_error_code(llvm::errc::no_such_file_or_directory);
89     if (I->second.isSymlink()) {
90       Output.clear();
91       Twine("/symlink").toVector(Output);
92       return std::error_code();
93     }
94     Output.clear();
95     Path.toVector(Output);
96     return std::error_code();
97   }
98 
99   struct DirIterImpl : public llvm::vfs::detail::DirIterImpl {
100     std::map<std::string, vfs::Status> &FilesAndDirs;
101     std::map<std::string, vfs::Status>::iterator I;
102     std::string Path;
103     bool isInPath(StringRef S) {
104       if (Path.size() < S.size() && S.find(Path) == 0) {
105         auto LastSep = S.find_last_of('/');
106         if (LastSep == Path.size() || LastSep == Path.size() - 1)
107           return true;
108       }
109       return false;
110     }
111     DirIterImpl(std::map<std::string, vfs::Status> &FilesAndDirs,
112                 const Twine &_Path)
113         : FilesAndDirs(FilesAndDirs), I(FilesAndDirs.begin()),
114           Path(_Path.str()) {
115       for (; I != FilesAndDirs.end(); ++I) {
116         if (isInPath(I->first)) {
117           CurrentEntry = vfs::directory_entry(std::string(I->second.getName()),
118                                               I->second.getType());
119           break;
120         }
121       }
122     }
123     std::error_code increment() override {
124       ++I;
125       for (; I != FilesAndDirs.end(); ++I) {
126         if (isInPath(I->first)) {
127           CurrentEntry = vfs::directory_entry(std::string(I->second.getName()),
128                                               I->second.getType());
129           break;
130         }
131       }
132       if (I == FilesAndDirs.end())
133         CurrentEntry = vfs::directory_entry();
134       return std::error_code();
135     }
136   };
137 
138   vfs::directory_iterator dir_begin(const Twine &Dir,
139                                     std::error_code &EC) override {
140     return vfs::directory_iterator(
141         std::make_shared<DirIterImpl>(FilesAndDirs, Dir));
142   }
143 
144   void addEntry(StringRef Path, const vfs::Status &Status) {
145     FilesAndDirs[std::string(Path)] = Status;
146   }
147 
148   const_iterator findEntry(const Twine &Path) const {
149     SmallString<128> P;
150     Path.toVector(P);
151     std::error_code EC = makeAbsolute(P);
152     assert(!EC);
153     (void)EC;
154     return FilesAndDirs.find(std::string(P.str()));
155   }
156 
157   void addRegularFile(StringRef Path, sys::fs::perms Perms = sys::fs::all_all) {
158     vfs::Status S(Path, UniqueID(FSID, FileID++),
159                   std::chrono::system_clock::now(), 0, 0, 1024,
160                   sys::fs::file_type::regular_file, Perms);
161     addEntry(Path, S);
162   }
163 
164   void addDirectory(StringRef Path, sys::fs::perms Perms = sys::fs::all_all) {
165     vfs::Status S(Path, UniqueID(FSID, FileID++),
166                   std::chrono::system_clock::now(), 0, 0, 0,
167                   sys::fs::file_type::directory_file, Perms);
168     addEntry(Path, S);
169   }
170 
171   void addSymlink(StringRef Path) {
172     vfs::Status S(Path, UniqueID(FSID, FileID++),
173                   std::chrono::system_clock::now(), 0, 0, 0,
174                   sys::fs::file_type::symlink_file, sys::fs::all_all);
175     addEntry(Path, S);
176   }
177 
178 protected:
179   void printImpl(raw_ostream &OS, PrintType Type,
180                  unsigned IndentLevel) const override {
181     printIndent(OS, IndentLevel);
182     OS << "DummyFileSystem (";
183     switch (Type) {
184     case vfs::FileSystem::PrintType::Summary:
185       OS << "Summary";
186       break;
187     case vfs::FileSystem::PrintType::Contents:
188       OS << "Contents";
189       break;
190     case vfs::FileSystem::PrintType::RecursiveContents:
191       OS << "RecursiveContents";
192       break;
193     }
194     OS << ")\n";
195   }
196 };
197 
198 class ErrorDummyFileSystem : public DummyFileSystem {
199   std::error_code setCurrentWorkingDirectory(const Twine &Path) override {
200     return llvm::errc::no_such_file_or_directory;
201   }
202 };
203 
204 /// Replace back-slashes by front-slashes.
205 std::string getPosixPath(const Twine &S) {
206   SmallString<128> Result;
207   llvm::sys::path::native(S, Result, llvm::sys::path::Style::posix);
208   return std::string(Result.str());
209 }
210 } // end anonymous namespace
211 
212 TEST(VirtualFileSystemTest, StatusQueries) {
213   IntrusiveRefCntPtr<DummyFileSystem> D(new DummyFileSystem());
214   ErrorOr<vfs::Status> Status((std::error_code()));
215 
216   D->addRegularFile("/foo");
217   Status = D->status("/foo");
218   ASSERT_FALSE(Status.getError());
219   EXPECT_TRUE(Status->isStatusKnown());
220   EXPECT_FALSE(Status->isDirectory());
221   EXPECT_TRUE(Status->isRegularFile());
222   EXPECT_FALSE(Status->isSymlink());
223   EXPECT_FALSE(Status->isOther());
224   EXPECT_TRUE(Status->exists());
225 
226   D->addDirectory("/bar");
227   Status = D->status("/bar");
228   ASSERT_FALSE(Status.getError());
229   EXPECT_TRUE(Status->isStatusKnown());
230   EXPECT_TRUE(Status->isDirectory());
231   EXPECT_FALSE(Status->isRegularFile());
232   EXPECT_FALSE(Status->isSymlink());
233   EXPECT_FALSE(Status->isOther());
234   EXPECT_TRUE(Status->exists());
235 
236   D->addSymlink("/baz");
237   Status = D->status("/baz");
238   ASSERT_FALSE(Status.getError());
239   EXPECT_TRUE(Status->isStatusKnown());
240   EXPECT_FALSE(Status->isDirectory());
241   EXPECT_FALSE(Status->isRegularFile());
242   EXPECT_TRUE(Status->isSymlink());
243   EXPECT_FALSE(Status->isOther());
244   EXPECT_TRUE(Status->exists());
245 
246   EXPECT_TRUE(Status->equivalent(*Status));
247   ErrorOr<vfs::Status> Status2 = D->status("/foo");
248   ASSERT_FALSE(Status2.getError());
249   EXPECT_FALSE(Status->equivalent(*Status2));
250 }
251 
252 TEST(VirtualFileSystemTest, BaseOnlyOverlay) {
253   IntrusiveRefCntPtr<DummyFileSystem> D(new DummyFileSystem());
254   ErrorOr<vfs::Status> Status((std::error_code()));
255   EXPECT_FALSE(Status = D->status("/foo"));
256 
257   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(new vfs::OverlayFileSystem(D));
258   EXPECT_FALSE(Status = O->status("/foo"));
259 
260   D->addRegularFile("/foo");
261   Status = D->status("/foo");
262   EXPECT_FALSE(Status.getError());
263 
264   ErrorOr<vfs::Status> Status2((std::error_code()));
265   Status2 = O->status("/foo");
266   EXPECT_FALSE(Status2.getError());
267   EXPECT_TRUE(Status->equivalent(*Status2));
268 }
269 
270 TEST(VirtualFileSystemTest, GetRealPathInOverlay) {
271   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
272   Lower->addRegularFile("/foo");
273   Lower->addSymlink("/lower_link");
274   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
275 
276   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
277       new vfs::OverlayFileSystem(Lower));
278   O->pushOverlay(Upper);
279 
280   // Regular file.
281   SmallString<16> RealPath;
282   EXPECT_FALSE(O->getRealPath("/foo", RealPath));
283   EXPECT_EQ(RealPath.str(), "/foo");
284 
285   // Expect no error getting real path for symlink in lower overlay.
286   EXPECT_FALSE(O->getRealPath("/lower_link", RealPath));
287   EXPECT_EQ(RealPath.str(), "/symlink");
288 
289   // Try a non-existing link.
290   EXPECT_EQ(O->getRealPath("/upper_link", RealPath),
291             errc::no_such_file_or_directory);
292 
293   // Add a new symlink in upper.
294   Upper->addSymlink("/upper_link");
295   EXPECT_FALSE(O->getRealPath("/upper_link", RealPath));
296   EXPECT_EQ(RealPath.str(), "/symlink");
297 }
298 
299 TEST(VirtualFileSystemTest, OverlayFiles) {
300   IntrusiveRefCntPtr<DummyFileSystem> Base(new DummyFileSystem());
301   IntrusiveRefCntPtr<DummyFileSystem> Middle(new DummyFileSystem());
302   IntrusiveRefCntPtr<DummyFileSystem> Top(new DummyFileSystem());
303   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
304       new vfs::OverlayFileSystem(Base));
305   O->pushOverlay(Middle);
306   O->pushOverlay(Top);
307 
308   ErrorOr<vfs::Status> Status1((std::error_code())),
309       Status2((std::error_code())), Status3((std::error_code())),
310       StatusB((std::error_code())), StatusM((std::error_code())),
311       StatusT((std::error_code()));
312 
313   Base->addRegularFile("/foo");
314   StatusB = Base->status("/foo");
315   ASSERT_FALSE(StatusB.getError());
316   Status1 = O->status("/foo");
317   ASSERT_FALSE(Status1.getError());
318   Middle->addRegularFile("/foo");
319   StatusM = Middle->status("/foo");
320   ASSERT_FALSE(StatusM.getError());
321   Status2 = O->status("/foo");
322   ASSERT_FALSE(Status2.getError());
323   Top->addRegularFile("/foo");
324   StatusT = Top->status("/foo");
325   ASSERT_FALSE(StatusT.getError());
326   Status3 = O->status("/foo");
327   ASSERT_FALSE(Status3.getError());
328 
329   EXPECT_TRUE(Status1->equivalent(*StatusB));
330   EXPECT_TRUE(Status2->equivalent(*StatusM));
331   EXPECT_TRUE(Status3->equivalent(*StatusT));
332 
333   EXPECT_FALSE(Status1->equivalent(*Status2));
334   EXPECT_FALSE(Status2->equivalent(*Status3));
335   EXPECT_FALSE(Status1->equivalent(*Status3));
336 }
337 
338 TEST(VirtualFileSystemTest, OverlayDirsNonMerged) {
339   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
340   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
341   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
342       new vfs::OverlayFileSystem(Lower));
343   O->pushOverlay(Upper);
344 
345   Lower->addDirectory("/lower-only");
346   Upper->addDirectory("/upper-only");
347 
348   // non-merged paths should be the same
349   ErrorOr<vfs::Status> Status1 = Lower->status("/lower-only");
350   ASSERT_FALSE(Status1.getError());
351   ErrorOr<vfs::Status> Status2 = O->status("/lower-only");
352   ASSERT_FALSE(Status2.getError());
353   EXPECT_TRUE(Status1->equivalent(*Status2));
354 
355   Status1 = Upper->status("/upper-only");
356   ASSERT_FALSE(Status1.getError());
357   Status2 = O->status("/upper-only");
358   ASSERT_FALSE(Status2.getError());
359   EXPECT_TRUE(Status1->equivalent(*Status2));
360 }
361 
362 TEST(VirtualFileSystemTest, MergedDirPermissions) {
363   // merged directories get the permissions of the upper dir
364   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
365   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
366   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
367       new vfs::OverlayFileSystem(Lower));
368   O->pushOverlay(Upper);
369 
370   ErrorOr<vfs::Status> Status((std::error_code()));
371   Lower->addDirectory("/both", sys::fs::owner_read);
372   Upper->addDirectory("/both", sys::fs::owner_all | sys::fs::group_read);
373   Status = O->status("/both");
374   ASSERT_FALSE(Status.getError());
375   EXPECT_EQ(0740, Status->getPermissions());
376 
377   // permissions (as usual) are not recursively applied
378   Lower->addRegularFile("/both/foo", sys::fs::owner_read);
379   Upper->addRegularFile("/both/bar", sys::fs::owner_write);
380   Status = O->status("/both/foo");
381   ASSERT_FALSE(Status.getError());
382   EXPECT_EQ(0400, Status->getPermissions());
383   Status = O->status("/both/bar");
384   ASSERT_FALSE(Status.getError());
385   EXPECT_EQ(0200, Status->getPermissions());
386 }
387 
388 TEST(VirtualFileSystemTest, OverlayIterator) {
389   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
390   Lower->addRegularFile("/foo");
391   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
392 
393   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
394       new vfs::OverlayFileSystem(Lower));
395   O->pushOverlay(Upper);
396 
397   ErrorOr<vfs::Status> Status((std::error_code()));
398   {
399     auto it = O->overlays_begin();
400     auto end = O->overlays_end();
401 
402     EXPECT_NE(it, end);
403 
404     Status = (*it)->status("/foo");
405     ASSERT_TRUE(Status.getError());
406 
407     it++;
408     EXPECT_NE(it, end);
409 
410     Status = (*it)->status("/foo");
411     ASSERT_FALSE(Status.getError());
412     EXPECT_TRUE(Status->exists());
413 
414     it++;
415     EXPECT_EQ(it, end);
416   }
417 
418   {
419     auto it = O->overlays_rbegin();
420     auto end = O->overlays_rend();
421 
422     EXPECT_NE(it, end);
423 
424     Status = (*it)->status("/foo");
425     ASSERT_FALSE(Status.getError());
426     EXPECT_TRUE(Status->exists());
427 
428     it++;
429     EXPECT_NE(it, end);
430 
431     Status = (*it)->status("/foo");
432     ASSERT_TRUE(Status.getError());
433 
434     it++;
435     EXPECT_EQ(it, end);
436   }
437 }
438 
439 TEST(VirtualFileSystemTest, BasicRealFSIteration) {
440   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
441   IntrusiveRefCntPtr<vfs::FileSystem> FS = vfs::getRealFileSystem();
442 
443   std::error_code EC;
444   vfs::directory_iterator I = FS->dir_begin(Twine(TestDirectory.path()), EC);
445   ASSERT_FALSE(EC);
446   EXPECT_EQ(vfs::directory_iterator(), I); // empty directory is empty
447 
448   TempDir _a(TestDirectory.path("a"));
449   TempDir _ab(TestDirectory.path("a/b"));
450   TempDir _c(TestDirectory.path("c"));
451   TempDir _cd(TestDirectory.path("c/d"));
452 
453   I = FS->dir_begin(Twine(TestDirectory.path()), EC);
454   ASSERT_FALSE(EC);
455   ASSERT_NE(vfs::directory_iterator(), I);
456   // Check either a or c, since we can't rely on the iteration order.
457   EXPECT_TRUE(I->path().ends_with("a") || I->path().ends_with("c"));
458   I.increment(EC);
459   ASSERT_FALSE(EC);
460   ASSERT_NE(vfs::directory_iterator(), I);
461   EXPECT_TRUE(I->path().ends_with("a") || I->path().ends_with("c"));
462   I.increment(EC);
463   EXPECT_EQ(vfs::directory_iterator(), I);
464 }
465 
466 #ifdef LLVM_ON_UNIX
467 TEST(VirtualFileSystemTest, MultipleWorkingDirs) {
468   // Our root contains a/aa, b/bb, c, where c is a link to a/.
469   // Run tests both in root/b/ and root/c/ (to test "normal" and symlink dirs).
470   // Interleave operations to show the working directories are independent.
471   TempDir Root("r", /*Unique*/ true);
472   TempDir ADir(Root.path("a"));
473   TempDir BDir(Root.path("b"));
474   TempLink C(ADir.path(), Root.path("c"));
475   TempFile AA(ADir.path("aa"), "", "aaaa");
476   TempFile BB(BDir.path("bb"), "", "bbbb");
477   std::unique_ptr<vfs::FileSystem> BFS = vfs::createPhysicalFileSystem(),
478                                    CFS = vfs::createPhysicalFileSystem();
479 
480   ASSERT_FALSE(BFS->setCurrentWorkingDirectory(BDir.path()));
481   ASSERT_FALSE(CFS->setCurrentWorkingDirectory(C.path()));
482   EXPECT_EQ(BDir.path(), *BFS->getCurrentWorkingDirectory());
483   EXPECT_EQ(C.path(), *CFS->getCurrentWorkingDirectory());
484 
485   // openFileForRead(), indirectly.
486   auto BBuf = BFS->getBufferForFile("bb");
487   ASSERT_TRUE(BBuf);
488   EXPECT_EQ("bbbb", (*BBuf)->getBuffer());
489 
490   auto ABuf = CFS->getBufferForFile("aa");
491   ASSERT_TRUE(ABuf);
492   EXPECT_EQ("aaaa", (*ABuf)->getBuffer());
493 
494   // status()
495   auto BStat = BFS->status("bb");
496   ASSERT_TRUE(BStat);
497   EXPECT_EQ("bb", BStat->getName());
498 
499   auto AStat = CFS->status("aa");
500   ASSERT_TRUE(AStat);
501   EXPECT_EQ("aa", AStat->getName()); // unresolved name
502 
503   // getRealPath()
504   SmallString<128> BPath;
505   ASSERT_FALSE(BFS->getRealPath("bb", BPath));
506   EXPECT_EQ(BB.path(), BPath);
507 
508   SmallString<128> APath;
509   ASSERT_FALSE(CFS->getRealPath("aa", APath));
510   EXPECT_EQ(AA.path(), APath); // Reports resolved name.
511 
512   // dir_begin
513   std::error_code EC;
514   auto BIt = BFS->dir_begin(".", EC);
515   ASSERT_FALSE(EC);
516   ASSERT_NE(BIt, vfs::directory_iterator());
517   EXPECT_EQ((BDir.path() + "/./bb").str(), BIt->path());
518   BIt.increment(EC);
519   ASSERT_FALSE(EC);
520   ASSERT_EQ(BIt, vfs::directory_iterator());
521 
522   auto CIt = CFS->dir_begin(".", EC);
523   ASSERT_FALSE(EC);
524   ASSERT_NE(CIt, vfs::directory_iterator());
525   EXPECT_EQ((ADir.path() + "/./aa").str(),
526             CIt->path()); // Partly resolved name!
527   CIt.increment(EC); // Because likely to read through this path.
528   ASSERT_FALSE(EC);
529   ASSERT_EQ(CIt, vfs::directory_iterator());
530 }
531 
532 TEST(VirtualFileSystemTest, PhysicalFileSystemWorkingDirFailure) {
533   TempDir D2("d2", /*Unique*/ true);
534   SmallString<128> WD, PrevWD;
535   ASSERT_EQ(sys::fs::current_path(PrevWD), std::error_code());
536   ASSERT_EQ(sys::fs::createUniqueDirectory("d1", WD), std::error_code());
537   ASSERT_EQ(sys::fs::set_current_path(WD), std::error_code());
538   auto Restore =
539       llvm::make_scope_exit([&] { sys::fs::set_current_path(PrevWD); });
540 
541   // Delete the working directory to create an error.
542   if (sys::fs::remove_directories(WD, /*IgnoreErrors=*/false))
543     // Some platforms (e.g. Solaris) disallow removal of the working directory.
544     GTEST_SKIP() << "test requires deletion of working directory";
545 
546   // Verify that we still get two separate working directories.
547   auto FS1 = vfs::createPhysicalFileSystem();
548   auto FS2 = vfs::createPhysicalFileSystem();
549   ASSERT_EQ(FS1->getCurrentWorkingDirectory().getError(),
550             errc::no_such_file_or_directory);
551   ASSERT_EQ(FS1->setCurrentWorkingDirectory(D2.path()), std::error_code());
552   ASSERT_EQ(FS1->getCurrentWorkingDirectory().get(), D2.path());
553   EXPECT_EQ(FS2->getCurrentWorkingDirectory().getError(),
554             errc::no_such_file_or_directory);
555   SmallString<128> WD2;
556   EXPECT_EQ(sys::fs::current_path(WD2), errc::no_such_file_or_directory);
557 }
558 
559 TEST(VirtualFileSystemTest, BrokenSymlinkRealFSIteration) {
560   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
561   IntrusiveRefCntPtr<vfs::FileSystem> FS = vfs::getRealFileSystem();
562 
563   TempLink _a("no_such_file", TestDirectory.path("a"));
564   TempDir _b(TestDirectory.path("b"));
565   TempLink _c("no_such_file", TestDirectory.path("c"));
566 
567   // Should get no iteration error, but a stat error for the broken symlinks.
568   std::map<std::string, std::error_code> StatResults;
569   std::error_code EC;
570   for (vfs::directory_iterator
571            I = FS->dir_begin(Twine(TestDirectory.path()), EC),
572            E;
573        I != E; I.increment(EC)) {
574     EXPECT_FALSE(EC);
575     StatResults[std::string(sys::path::filename(I->path()))] =
576         FS->status(I->path()).getError();
577   }
578   EXPECT_THAT(
579       StatResults,
580       ElementsAre(
581           Pair("a", std::make_error_code(std::errc::no_such_file_or_directory)),
582           Pair("b", std::error_code()),
583           Pair("c",
584                std::make_error_code(std::errc::no_such_file_or_directory))));
585 }
586 #endif
587 
588 TEST(VirtualFileSystemTest, BasicRealFSRecursiveIteration) {
589   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
590   IntrusiveRefCntPtr<vfs::FileSystem> FS = vfs::getRealFileSystem();
591 
592   std::error_code EC;
593   auto I =
594       vfs::recursive_directory_iterator(*FS, Twine(TestDirectory.path()), EC);
595   ASSERT_FALSE(EC);
596   EXPECT_EQ(vfs::recursive_directory_iterator(), I); // empty directory is empty
597 
598   TempDir _a(TestDirectory.path("a"));
599   TempDir _ab(TestDirectory.path("a/b"));
600   TempDir _c(TestDirectory.path("c"));
601   TempDir _cd(TestDirectory.path("c/d"));
602 
603   I = vfs::recursive_directory_iterator(*FS, Twine(TestDirectory.path()), EC);
604   ASSERT_FALSE(EC);
605   ASSERT_NE(vfs::recursive_directory_iterator(), I);
606 
607   std::vector<std::string> Contents;
608   for (auto E = vfs::recursive_directory_iterator(); !EC && I != E;
609        I.increment(EC)) {
610     Contents.push_back(std::string(I->path()));
611   }
612 
613   // Check contents, which may be in any order
614   EXPECT_EQ(4U, Contents.size());
615   int Counts[4] = {0, 0, 0, 0};
616   for (const std::string &Name : Contents) {
617     ASSERT_FALSE(Name.empty());
618     int Index = Name[Name.size() - 1] - 'a';
619     ASSERT_GE(Index, 0);
620     ASSERT_LT(Index, 4);
621     Counts[Index]++;
622   }
623   EXPECT_EQ(1, Counts[0]); // a
624   EXPECT_EQ(1, Counts[1]); // b
625   EXPECT_EQ(1, Counts[2]); // c
626   EXPECT_EQ(1, Counts[3]); // d
627 }
628 
629 TEST(VirtualFileSystemTest, BasicRealFSRecursiveIterationNoPush) {
630   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
631 
632   TempDir _a(TestDirectory.path("a"));
633   TempDir _ab(TestDirectory.path("a/b"));
634   TempDir _c(TestDirectory.path("c"));
635   TempDir _cd(TestDirectory.path("c/d"));
636   TempDir _e(TestDirectory.path("e"));
637   TempDir _ef(TestDirectory.path("e/f"));
638   TempDir _g(TestDirectory.path("g"));
639 
640   IntrusiveRefCntPtr<vfs::FileSystem> FS = vfs::getRealFileSystem();
641 
642   // Test that calling no_push on entries without subdirectories has no effect.
643   {
644     std::error_code EC;
645     auto I =
646         vfs::recursive_directory_iterator(*FS, Twine(TestDirectory.path()), EC);
647     ASSERT_FALSE(EC);
648 
649     std::vector<std::string> Contents;
650     for (auto E = vfs::recursive_directory_iterator(); !EC && I != E;
651          I.increment(EC)) {
652       Contents.push_back(std::string(I->path()));
653       char last = I->path().back();
654       switch (last) {
655       case 'b':
656       case 'd':
657       case 'f':
658       case 'g':
659         I.no_push();
660         break;
661       default:
662         break;
663       }
664     }
665     EXPECT_EQ(7U, Contents.size());
666   }
667 
668   // Test that calling no_push skips subdirectories.
669   {
670     std::error_code EC;
671     auto I =
672         vfs::recursive_directory_iterator(*FS, Twine(TestDirectory.path()), EC);
673     ASSERT_FALSE(EC);
674 
675     std::vector<std::string> Contents;
676     for (auto E = vfs::recursive_directory_iterator(); !EC && I != E;
677          I.increment(EC)) {
678       Contents.push_back(std::string(I->path()));
679       char last = I->path().back();
680       switch (last) {
681       case 'a':
682       case 'c':
683       case 'e':
684         I.no_push();
685         break;
686       default:
687         break;
688       }
689     }
690 
691     // Check contents, which may be in any order
692     EXPECT_EQ(4U, Contents.size());
693     int Counts[7] = {0, 0, 0, 0, 0, 0, 0};
694     for (const std::string &Name : Contents) {
695       ASSERT_FALSE(Name.empty());
696       int Index = Name[Name.size() - 1] - 'a';
697       ASSERT_GE(Index, 0);
698       ASSERT_LT(Index, 7);
699       Counts[Index]++;
700     }
701     EXPECT_EQ(1, Counts[0]); // a
702     EXPECT_EQ(0, Counts[1]); // b
703     EXPECT_EQ(1, Counts[2]); // c
704     EXPECT_EQ(0, Counts[3]); // d
705     EXPECT_EQ(1, Counts[4]); // e
706     EXPECT_EQ(0, Counts[5]); // f
707     EXPECT_EQ(1, Counts[6]); // g
708   }
709 }
710 
711 #ifdef LLVM_ON_UNIX
712 TEST(VirtualFileSystemTest, BrokenSymlinkRealFSRecursiveIteration) {
713   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
714   IntrusiveRefCntPtr<vfs::FileSystem> FS = vfs::getRealFileSystem();
715 
716   TempLink _a("no_such_file", TestDirectory.path("a"));
717   TempDir _b(TestDirectory.path("b"));
718   TempLink _ba("no_such_file", TestDirectory.path("b/a"));
719   TempDir _bb(TestDirectory.path("b/b"));
720   TempLink _bc("no_such_file", TestDirectory.path("b/c"));
721   TempLink _c("no_such_file", TestDirectory.path("c"));
722   TempDir _d(TestDirectory.path("d"));
723   TempDir _dd(TestDirectory.path("d/d"));
724   TempDir _ddd(TestDirectory.path("d/d/d"));
725   TempLink _e("no_such_file", TestDirectory.path("e"));
726 
727   std::vector<std::string> VisitedBrokenSymlinks;
728   std::vector<std::string> VisitedNonBrokenSymlinks;
729   std::error_code EC;
730   for (vfs::recursive_directory_iterator
731            I(*FS, Twine(TestDirectory.path()), EC),
732        E;
733        I != E; I.increment(EC)) {
734     EXPECT_FALSE(EC);
735     (FS->status(I->path()) ? VisitedNonBrokenSymlinks : VisitedBrokenSymlinks)
736         .push_back(std::string(I->path()));
737   }
738 
739   // Check visited file names.
740   EXPECT_THAT(VisitedBrokenSymlinks,
741               UnorderedElementsAre(_a.path().str(), _ba.path().str(),
742                                    _bc.path().str(), _c.path().str(),
743                                    _e.path().str()));
744   EXPECT_THAT(VisitedNonBrokenSymlinks,
745               UnorderedElementsAre(_b.path().str(), _bb.path().str(),
746                                    _d.path().str(), _dd.path().str(),
747                                    _ddd.path().str()));
748 }
749 #endif
750 
751 template <typename DirIter>
752 static void checkContents(DirIter I, ArrayRef<StringRef> ExpectedOut) {
753   std::error_code EC;
754   SmallVector<StringRef, 4> Expected(ExpectedOut.begin(), ExpectedOut.end());
755   SmallVector<std::string, 4> InputToCheck;
756 
757   // Do not rely on iteration order to check for contents, sort both
758   // content vectors before comparison.
759   for (DirIter E; !EC && I != E; I.increment(EC))
760     InputToCheck.push_back(std::string(I->path()));
761 
762   llvm::sort(InputToCheck);
763   llvm::sort(Expected);
764   EXPECT_EQ(InputToCheck.size(), Expected.size());
765 
766   unsigned LastElt = std::min(InputToCheck.size(), Expected.size());
767   for (unsigned Idx = 0; Idx != LastElt; ++Idx)
768     EXPECT_EQ(StringRef(InputToCheck[Idx]), Expected[Idx]);
769 }
770 
771 TEST(VirtualFileSystemTest, OverlayIteration) {
772   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
773   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
774   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
775       new vfs::OverlayFileSystem(Lower));
776   O->pushOverlay(Upper);
777 
778   std::error_code EC;
779   checkContents(O->dir_begin("/", EC), ArrayRef<StringRef>());
780 
781   Lower->addRegularFile("/file1");
782   checkContents(O->dir_begin("/", EC), ArrayRef<StringRef>("/file1"));
783 
784   Upper->addRegularFile("/file2");
785   checkContents(O->dir_begin("/", EC), {"/file2", "/file1"});
786 
787   Lower->addDirectory("/dir1");
788   Lower->addRegularFile("/dir1/foo");
789   Upper->addDirectory("/dir2");
790   Upper->addRegularFile("/dir2/foo");
791   checkContents(O->dir_begin("/dir2", EC), ArrayRef<StringRef>("/dir2/foo"));
792   checkContents(O->dir_begin("/", EC), {"/dir2", "/file2", "/dir1", "/file1"});
793 }
794 
795 TEST(VirtualFileSystemTest, OverlayRecursiveIteration) {
796   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
797   IntrusiveRefCntPtr<DummyFileSystem> Middle(new DummyFileSystem());
798   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
799   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
800       new vfs::OverlayFileSystem(Lower));
801   O->pushOverlay(Middle);
802   O->pushOverlay(Upper);
803 
804   std::error_code EC;
805   checkContents(vfs::recursive_directory_iterator(*O, "/", EC),
806                 ArrayRef<StringRef>());
807 
808   Lower->addRegularFile("/file1");
809   checkContents(vfs::recursive_directory_iterator(*O, "/", EC),
810                 ArrayRef<StringRef>("/file1"));
811 
812   Upper->addDirectory("/dir");
813   Upper->addRegularFile("/dir/file2");
814   checkContents(vfs::recursive_directory_iterator(*O, "/", EC),
815                 {"/dir", "/dir/file2", "/file1"});
816 
817   Lower->addDirectory("/dir1");
818   Lower->addRegularFile("/dir1/foo");
819   Lower->addDirectory("/dir1/a");
820   Lower->addRegularFile("/dir1/a/b");
821   Middle->addDirectory("/a");
822   Middle->addDirectory("/a/b");
823   Middle->addDirectory("/a/b/c");
824   Middle->addRegularFile("/a/b/c/d");
825   Middle->addRegularFile("/hiddenByUp");
826   Upper->addDirectory("/dir2");
827   Upper->addRegularFile("/dir2/foo");
828   Upper->addRegularFile("/hiddenByUp");
829   checkContents(vfs::recursive_directory_iterator(*O, "/dir2", EC),
830                 ArrayRef<StringRef>("/dir2/foo"));
831   checkContents(vfs::recursive_directory_iterator(*O, "/", EC),
832                 {"/dir", "/dir/file2", "/dir2", "/dir2/foo", "/hiddenByUp",
833                  "/a", "/a/b", "/a/b/c", "/a/b/c/d", "/dir1", "/dir1/a",
834                  "/dir1/a/b", "/dir1/foo", "/file1"});
835 }
836 
837 TEST(VirtualFileSystemTest, ThreeLevelIteration) {
838   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
839   IntrusiveRefCntPtr<DummyFileSystem> Middle(new DummyFileSystem());
840   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
841   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
842       new vfs::OverlayFileSystem(Lower));
843   O->pushOverlay(Middle);
844   O->pushOverlay(Upper);
845 
846   std::error_code EC;
847   checkContents(O->dir_begin("/", EC), ArrayRef<StringRef>());
848 
849   Middle->addRegularFile("/file2");
850   checkContents(O->dir_begin("/", EC), ArrayRef<StringRef>("/file2"));
851 
852   Lower->addRegularFile("/file1");
853   Upper->addRegularFile("/file3");
854   checkContents(O->dir_begin("/", EC), {"/file3", "/file2", "/file1"});
855 }
856 
857 TEST(VirtualFileSystemTest, HiddenInIteration) {
858   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
859   IntrusiveRefCntPtr<DummyFileSystem> Middle(new DummyFileSystem());
860   IntrusiveRefCntPtr<DummyFileSystem> Upper(new DummyFileSystem());
861   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
862       new vfs::OverlayFileSystem(Lower));
863   O->pushOverlay(Middle);
864   O->pushOverlay(Upper);
865 
866   std::error_code EC;
867   Lower->addRegularFile("/onlyInLow");
868   Lower->addDirectory("/hiddenByMid");
869   Lower->addDirectory("/hiddenByUp");
870   Middle->addRegularFile("/onlyInMid");
871   Middle->addRegularFile("/hiddenByMid");
872   Middle->addDirectory("/hiddenByUp");
873   Upper->addRegularFile("/onlyInUp");
874   Upper->addRegularFile("/hiddenByUp");
875   checkContents(
876       O->dir_begin("/", EC),
877       {"/hiddenByUp", "/onlyInUp", "/hiddenByMid", "/onlyInMid", "/onlyInLow"});
878 
879   // Make sure we get the top-most entry
880   {
881     std::error_code EC;
882     vfs::directory_iterator I = O->dir_begin("/", EC), E;
883     for (; !EC && I != E; I.increment(EC))
884       if (I->path() == "/hiddenByUp")
885         break;
886     ASSERT_NE(E, I);
887     EXPECT_EQ(sys::fs::file_type::regular_file, I->type());
888   }
889   {
890     std::error_code EC;
891     vfs::directory_iterator I = O->dir_begin("/", EC), E;
892     for (; !EC && I != E; I.increment(EC))
893       if (I->path() == "/hiddenByMid")
894         break;
895     ASSERT_NE(E, I);
896     EXPECT_EQ(sys::fs::file_type::regular_file, I->type());
897   }
898 }
899 
900 TEST(VirtualFileSystemTest, Visit) {
901   IntrusiveRefCntPtr<DummyFileSystem> Base(new DummyFileSystem());
902   IntrusiveRefCntPtr<DummyFileSystem> Middle(new DummyFileSystem());
903   IntrusiveRefCntPtr<DummyFileSystem> Top(new DummyFileSystem());
904   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
905       new vfs::OverlayFileSystem(Base));
906   O->pushOverlay(Middle);
907   O->pushOverlay(Top);
908 
909   auto YAML =
910       MemoryBuffer::getMemBuffer("{\n"
911                                  "  'version': 0,\n"
912                                  "  'redirecting-with': 'redirect-only',\n"
913                                  "  'roots': [\n"
914                                  "    {\n"
915                                  "      'type': 'file',\n"
916                                  "      'name': '/vfile',\n"
917                                  "      'external-contents': '/a',\n"
918                                  "    },"
919                                  "  ]\n"
920                                  "}");
921 
922   IntrusiveRefCntPtr<vfs::RedirectingFileSystem> Redirecting =
923       vfs::RedirectingFileSystem::create(std::move(YAML), nullptr, "", nullptr,
924                                          O)
925           .release();
926 
927   vfs::ProxyFileSystem PFS(Redirecting);
928 
929   std::vector<const vfs::FileSystem *> FSs;
930   PFS.visit([&](const vfs::FileSystem &FS) { FSs.push_back(&FS); });
931 
932   ASSERT_EQ(size_t(6), FSs.size());
933   EXPECT_TRUE(isa<vfs::ProxyFileSystem>(FSs[0]));
934   EXPECT_TRUE(isa<vfs::RedirectingFileSystem>(FSs[1]));
935   EXPECT_TRUE(isa<vfs::OverlayFileSystem>(FSs[2]));
936   EXPECT_TRUE(isa<vfs::FileSystem>(FSs[3]));
937   EXPECT_TRUE(isa<vfs::FileSystem>(FSs[4]));
938   EXPECT_TRUE(isa<vfs::FileSystem>(FSs[5]));
939 }
940 
941 TEST(OverlayFileSystemTest, PrintOutput) {
942   auto Dummy = makeIntrusiveRefCnt<DummyFileSystem>();
943   auto Overlay1 = makeIntrusiveRefCnt<vfs::OverlayFileSystem>(Dummy);
944   Overlay1->pushOverlay(Dummy);
945   auto Overlay2 = makeIntrusiveRefCnt<vfs::OverlayFileSystem>(Overlay1);
946   Overlay2->pushOverlay(Dummy);
947 
948   SmallString<0> Output;
949   raw_svector_ostream OuputStream{Output};
950 
951   Overlay2->print(OuputStream, vfs::FileSystem::PrintType::Summary);
952   ASSERT_EQ("OverlayFileSystem\n", Output);
953 
954   Output.clear();
955   Overlay2->print(OuputStream, vfs::FileSystem::PrintType::Contents);
956   ASSERT_EQ("OverlayFileSystem\n"
957             "  DummyFileSystem (Summary)\n"
958             "  OverlayFileSystem\n",
959             Output);
960 
961   Output.clear();
962   Overlay2->print(OuputStream, vfs::FileSystem::PrintType::RecursiveContents);
963   ASSERT_EQ("OverlayFileSystem\n"
964             "  DummyFileSystem (RecursiveContents)\n"
965             "  OverlayFileSystem\n"
966             "    DummyFileSystem (RecursiveContents)\n"
967             "    DummyFileSystem (RecursiveContents)\n",
968             Output);
969 }
970 
971 TEST(ProxyFileSystemTest, Basic) {
972   IntrusiveRefCntPtr<vfs::InMemoryFileSystem> Base(
973       new vfs::InMemoryFileSystem());
974   vfs::ProxyFileSystem PFS(Base);
975 
976   Base->addFile("/a", 0, MemoryBuffer::getMemBuffer("test"));
977 
978   auto Stat = PFS.status("/a");
979   ASSERT_FALSE(Stat.getError());
980 
981   auto File = PFS.openFileForRead("/a");
982   ASSERT_FALSE(File.getError());
983   EXPECT_EQ("test", (*(*File)->getBuffer("ignored"))->getBuffer());
984 
985   std::error_code EC;
986   vfs::directory_iterator I = PFS.dir_begin("/", EC);
987   ASSERT_FALSE(EC);
988   ASSERT_EQ("/a", I->path());
989   I.increment(EC);
990   ASSERT_FALSE(EC);
991   ASSERT_EQ(vfs::directory_iterator(), I);
992 
993   ASSERT_FALSE(PFS.setCurrentWorkingDirectory("/"));
994 
995   auto PWD = PFS.getCurrentWorkingDirectory();
996   ASSERT_FALSE(PWD.getError());
997   ASSERT_EQ("/", getPosixPath(*PWD));
998 
999   SmallString<16> Path;
1000   ASSERT_FALSE(PFS.getRealPath("a", Path));
1001   ASSERT_EQ("/a", getPosixPath(Path));
1002 
1003   bool Local = true;
1004   ASSERT_FALSE(PFS.isLocal("/a", Local));
1005   EXPECT_FALSE(Local);
1006 }
1007 
1008 class InMemoryFileSystemTest : public ::testing::Test {
1009 protected:
1010   llvm::vfs::InMemoryFileSystem FS;
1011   llvm::vfs::InMemoryFileSystem NormalizedFS;
1012 
1013   InMemoryFileSystemTest()
1014       : FS(/*UseNormalizedPaths=*/false),
1015         NormalizedFS(/*UseNormalizedPaths=*/true) {}
1016 };
1017 
1018 MATCHER_P2(IsHardLinkTo, FS, Target, "") {
1019   StringRef From = arg;
1020   StringRef To = Target;
1021   auto OpenedFrom = FS->openFileForRead(From);
1022   auto OpenedTo = FS->openFileForRead(To);
1023   return !OpenedFrom.getError() && !OpenedTo.getError() &&
1024          (*OpenedFrom)->status()->getUniqueID() ==
1025              (*OpenedTo)->status()->getUniqueID();
1026 }
1027 
1028 TEST_F(InMemoryFileSystemTest, IsEmpty) {
1029   auto Stat = FS.status("/a");
1030   ASSERT_EQ(Stat.getError(), errc::no_such_file_or_directory) << FS.toString();
1031   Stat = FS.status("/");
1032   ASSERT_EQ(Stat.getError(), errc::no_such_file_or_directory) << FS.toString();
1033 }
1034 
1035 TEST_F(InMemoryFileSystemTest, WindowsPath) {
1036   FS.addFile("c:/windows/system128/foo.cpp", 0, MemoryBuffer::getMemBuffer(""));
1037   auto Stat = FS.status("c:");
1038 #if !defined(_WIN32)
1039   ASSERT_FALSE(Stat.getError()) << Stat.getError() << FS.toString();
1040 #endif
1041   Stat = FS.status("c:/windows/system128/foo.cpp");
1042   ASSERT_FALSE(Stat.getError()) << Stat.getError() << FS.toString();
1043   FS.addFile("d:/windows/foo.cpp", 0, MemoryBuffer::getMemBuffer(""));
1044   Stat = FS.status("d:/windows/foo.cpp");
1045   ASSERT_FALSE(Stat.getError()) << Stat.getError() << FS.toString();
1046 }
1047 
1048 TEST_F(InMemoryFileSystemTest, OverlayFile) {
1049   FS.addFile("/a", 0, MemoryBuffer::getMemBuffer("a"));
1050   NormalizedFS.addFile("/a", 0, MemoryBuffer::getMemBuffer("a"));
1051   auto Stat = FS.status("/");
1052   ASSERT_FALSE(Stat.getError()) << Stat.getError() << FS.toString();
1053   Stat = FS.status("/.");
1054   ASSERT_FALSE(Stat);
1055   Stat = NormalizedFS.status("/.");
1056   ASSERT_FALSE(Stat.getError()) << Stat.getError() << FS.toString();
1057   Stat = FS.status("/a");
1058   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1059   ASSERT_EQ("/a", Stat->getName());
1060 }
1061 
1062 TEST_F(InMemoryFileSystemTest, OverlayFileNoOwn) {
1063   auto Buf = MemoryBuffer::getMemBuffer("a");
1064   FS.addFileNoOwn("/a", 0, *Buf);
1065   auto Stat = FS.status("/a");
1066   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1067   ASSERT_EQ("/a", Stat->getName());
1068 }
1069 
1070 TEST_F(InMemoryFileSystemTest, OpenFileForRead) {
1071   FS.addFile("/a", 0, MemoryBuffer::getMemBuffer("a"));
1072   FS.addFile("././c", 0, MemoryBuffer::getMemBuffer("c"));
1073   FS.addFile("./d/../d", 0, MemoryBuffer::getMemBuffer("d"));
1074   NormalizedFS.addFile("/a", 0, MemoryBuffer::getMemBuffer("a"));
1075   NormalizedFS.addFile("././c", 0, MemoryBuffer::getMemBuffer("c"));
1076   NormalizedFS.addFile("./d/../d", 0, MemoryBuffer::getMemBuffer("d"));
1077   auto File = FS.openFileForRead("/a");
1078   ASSERT_EQ("a", (*(*File)->getBuffer("ignored"))->getBuffer());
1079   File = FS.openFileForRead("/a"); // Open again.
1080   ASSERT_EQ("a", (*(*File)->getBuffer("ignored"))->getBuffer());
1081   File = NormalizedFS.openFileForRead("/././a"); // Open again.
1082   ASSERT_EQ("a", (*(*File)->getBuffer("ignored"))->getBuffer());
1083   File = FS.openFileForRead("/");
1084   ASSERT_EQ(File.getError(), errc::invalid_argument) << FS.toString();
1085   File = FS.openFileForRead("/b");
1086   ASSERT_EQ(File.getError(), errc::no_such_file_or_directory) << FS.toString();
1087   File = FS.openFileForRead("./c");
1088   ASSERT_FALSE(File);
1089   File = FS.openFileForRead("e/../d");
1090   ASSERT_FALSE(File);
1091   File = NormalizedFS.openFileForRead("./c");
1092   ASSERT_EQ("c", (*(*File)->getBuffer("ignored"))->getBuffer());
1093   File = NormalizedFS.openFileForRead("e/../d");
1094   ASSERT_EQ("d", (*(*File)->getBuffer("ignored"))->getBuffer());
1095 }
1096 
1097 TEST_F(InMemoryFileSystemTest, DuplicatedFile) {
1098   ASSERT_TRUE(FS.addFile("/a", 0, MemoryBuffer::getMemBuffer("a")));
1099   ASSERT_FALSE(FS.addFile("/a/b", 0, MemoryBuffer::getMemBuffer("a")));
1100   ASSERT_TRUE(FS.addFile("/a", 0, MemoryBuffer::getMemBuffer("a")));
1101   ASSERT_FALSE(FS.addFile("/a", 0, MemoryBuffer::getMemBuffer("b")));
1102 }
1103 
1104 TEST_F(InMemoryFileSystemTest, DirectoryIteration) {
1105   FS.addFile("/a", 0, MemoryBuffer::getMemBuffer(""));
1106   FS.addFile("/b/c", 0, MemoryBuffer::getMemBuffer(""));
1107 
1108   std::error_code EC;
1109   vfs::directory_iterator I = FS.dir_begin("/", EC);
1110   ASSERT_FALSE(EC);
1111   ASSERT_EQ("/a", I->path());
1112   I.increment(EC);
1113   ASSERT_FALSE(EC);
1114   ASSERT_EQ("/b", I->path());
1115   I.increment(EC);
1116   ASSERT_FALSE(EC);
1117   ASSERT_EQ(vfs::directory_iterator(), I);
1118 
1119   I = FS.dir_begin("/b", EC);
1120   ASSERT_FALSE(EC);
1121   // When on Windows, we end up with "/b\\c" as the name.  Convert to Posix
1122   // path for the sake of the comparison.
1123   ASSERT_EQ("/b/c", getPosixPath(std::string(I->path())));
1124   I.increment(EC);
1125   ASSERT_FALSE(EC);
1126   ASSERT_EQ(vfs::directory_iterator(), I);
1127 }
1128 
1129 TEST_F(InMemoryFileSystemTest, WorkingDirectory) {
1130   FS.setCurrentWorkingDirectory("/b");
1131   FS.addFile("c", 0, MemoryBuffer::getMemBuffer(""));
1132 
1133   auto Stat = FS.status("/b/c");
1134   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1135   ASSERT_EQ("/b/c", Stat->getName());
1136   ASSERT_EQ("/b", *FS.getCurrentWorkingDirectory());
1137 
1138   Stat = FS.status("c");
1139   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1140 
1141   NormalizedFS.setCurrentWorkingDirectory("/b/c");
1142   NormalizedFS.setCurrentWorkingDirectory(".");
1143   ASSERT_EQ("/b/c",
1144             getPosixPath(NormalizedFS.getCurrentWorkingDirectory().get()));
1145   NormalizedFS.setCurrentWorkingDirectory("..");
1146   ASSERT_EQ("/b",
1147             getPosixPath(NormalizedFS.getCurrentWorkingDirectory().get()));
1148 }
1149 
1150 TEST_F(InMemoryFileSystemTest, IsLocal) {
1151   FS.setCurrentWorkingDirectory("/b");
1152   FS.addFile("c", 0, MemoryBuffer::getMemBuffer(""));
1153 
1154   std::error_code EC;
1155   bool IsLocal = true;
1156   EC = FS.isLocal("c", IsLocal);
1157   ASSERT_FALSE(EC);
1158   ASSERT_FALSE(IsLocal);
1159 }
1160 
1161 #if !defined(_WIN32)
1162 TEST_F(InMemoryFileSystemTest, GetRealPath) {
1163   SmallString<16> Path;
1164   EXPECT_EQ(FS.getRealPath("b", Path), errc::operation_not_permitted);
1165 
1166   auto GetRealPath = [this](StringRef P) {
1167     SmallString<16> Output;
1168     auto EC = FS.getRealPath(P, Output);
1169     EXPECT_FALSE(EC);
1170     return std::string(Output);
1171   };
1172 
1173   FS.setCurrentWorkingDirectory("a");
1174   EXPECT_EQ(GetRealPath("b"), "a/b");
1175   EXPECT_EQ(GetRealPath("../b"), "b");
1176   EXPECT_EQ(GetRealPath("b/./c"), "a/b/c");
1177 
1178   FS.setCurrentWorkingDirectory("/a");
1179   EXPECT_EQ(GetRealPath("b"), "/a/b");
1180   EXPECT_EQ(GetRealPath("../b"), "/b");
1181   EXPECT_EQ(GetRealPath("b/./c"), "/a/b/c");
1182 }
1183 #endif // _WIN32
1184 
1185 TEST_F(InMemoryFileSystemTest, AddFileWithUser) {
1186   FS.addFile("/a/b/c", 0, MemoryBuffer::getMemBuffer("abc"), 0xFEEDFACE);
1187   auto Stat = FS.status("/a");
1188   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1189   ASSERT_TRUE(Stat->isDirectory());
1190   ASSERT_EQ(0xFEEDFACE, Stat->getUser());
1191   Stat = FS.status("/a/b");
1192   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1193   ASSERT_TRUE(Stat->isDirectory());
1194   ASSERT_EQ(0xFEEDFACE, Stat->getUser());
1195   Stat = FS.status("/a/b/c");
1196   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1197   ASSERT_TRUE(Stat->isRegularFile());
1198   ASSERT_EQ(sys::fs::perms::all_all, Stat->getPermissions());
1199   ASSERT_EQ(0xFEEDFACE, Stat->getUser());
1200 }
1201 
1202 TEST_F(InMemoryFileSystemTest, AddFileWithGroup) {
1203   FS.addFile("/a/b/c", 0, MemoryBuffer::getMemBuffer("abc"), std::nullopt,
1204              0xDABBAD00);
1205   auto Stat = FS.status("/a");
1206   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1207   ASSERT_TRUE(Stat->isDirectory());
1208   ASSERT_EQ(0xDABBAD00, Stat->getGroup());
1209   Stat = FS.status("/a/b");
1210   ASSERT_TRUE(Stat->isDirectory());
1211   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1212   ASSERT_EQ(0xDABBAD00, Stat->getGroup());
1213   Stat = FS.status("/a/b/c");
1214   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1215   ASSERT_TRUE(Stat->isRegularFile());
1216   ASSERT_EQ(sys::fs::perms::all_all, Stat->getPermissions());
1217   ASSERT_EQ(0xDABBAD00, Stat->getGroup());
1218 }
1219 
1220 TEST_F(InMemoryFileSystemTest, AddFileWithFileType) {
1221   FS.addFile("/a/b/c", 0, MemoryBuffer::getMemBuffer("abc"), std::nullopt,
1222              std::nullopt, sys::fs::file_type::socket_file);
1223   auto Stat = FS.status("/a");
1224   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1225   ASSERT_TRUE(Stat->isDirectory());
1226   Stat = FS.status("/a/b");
1227   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1228   ASSERT_TRUE(Stat->isDirectory());
1229   Stat = FS.status("/a/b/c");
1230   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1231   ASSERT_EQ(sys::fs::file_type::socket_file, Stat->getType());
1232   ASSERT_EQ(sys::fs::perms::all_all, Stat->getPermissions());
1233 }
1234 
1235 TEST_F(InMemoryFileSystemTest, AddFileWithPerms) {
1236   FS.addFile("/a/b/c", 0, MemoryBuffer::getMemBuffer("abc"), std::nullopt,
1237              std::nullopt, std::nullopt,
1238              sys::fs::perms::owner_read | sys::fs::perms::owner_write);
1239   auto Stat = FS.status("/a");
1240   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1241   ASSERT_TRUE(Stat->isDirectory());
1242   ASSERT_EQ(sys::fs::perms::owner_read | sys::fs::perms::owner_write |
1243                 sys::fs::perms::owner_exe,
1244             Stat->getPermissions());
1245   Stat = FS.status("/a/b");
1246   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1247   ASSERT_TRUE(Stat->isDirectory());
1248   ASSERT_EQ(sys::fs::perms::owner_read | sys::fs::perms::owner_write |
1249                 sys::fs::perms::owner_exe,
1250             Stat->getPermissions());
1251   Stat = FS.status("/a/b/c");
1252   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1253   ASSERT_TRUE(Stat->isRegularFile());
1254   ASSERT_EQ(sys::fs::perms::owner_read | sys::fs::perms::owner_write,
1255             Stat->getPermissions());
1256 }
1257 
1258 TEST_F(InMemoryFileSystemTest, AddDirectoryThenAddChild) {
1259   FS.addFile("/a", 0, MemoryBuffer::getMemBuffer(""), /*User=*/std::nullopt,
1260              /*Group=*/std::nullopt, sys::fs::file_type::directory_file);
1261   FS.addFile("/a/b", 0, MemoryBuffer::getMemBuffer("abc"),
1262              /*User=*/std::nullopt,
1263              /*Group=*/std::nullopt, sys::fs::file_type::regular_file);
1264   auto Stat = FS.status("/a");
1265   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1266   ASSERT_TRUE(Stat->isDirectory());
1267   Stat = FS.status("/a/b");
1268   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n" << FS.toString();
1269   ASSERT_TRUE(Stat->isRegularFile());
1270 }
1271 
1272 // Test that the name returned by status() is in the same form as the path that
1273 // was requested (to match the behavior of RealFileSystem).
1274 TEST_F(InMemoryFileSystemTest, StatusName) {
1275   NormalizedFS.addFile("/a/b/c", 0, MemoryBuffer::getMemBuffer("abc"),
1276                        /*User=*/std::nullopt,
1277                        /*Group=*/std::nullopt,
1278                        sys::fs::file_type::regular_file);
1279   NormalizedFS.setCurrentWorkingDirectory("/a/b");
1280 
1281   // Access using InMemoryFileSystem::status.
1282   auto Stat = NormalizedFS.status("../b/c");
1283   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n"
1284                                 << NormalizedFS.toString();
1285   ASSERT_TRUE(Stat->isRegularFile());
1286   ASSERT_EQ("../b/c", Stat->getName());
1287 
1288   // Access using InMemoryFileAdaptor::status.
1289   auto File = NormalizedFS.openFileForRead("../b/c");
1290   ASSERT_FALSE(File.getError()) << File.getError() << "\n"
1291                                 << NormalizedFS.toString();
1292   Stat = (*File)->status();
1293   ASSERT_FALSE(Stat.getError()) << Stat.getError() << "\n"
1294                                 << NormalizedFS.toString();
1295   ASSERT_TRUE(Stat->isRegularFile());
1296   ASSERT_EQ("../b/c", Stat->getName());
1297 
1298   // Access using a directory iterator.
1299   std::error_code EC;
1300   llvm::vfs::directory_iterator It = NormalizedFS.dir_begin("../b", EC);
1301   // When on Windows, we end up with "../b\\c" as the name.  Convert to Posix
1302   // path for the sake of the comparison.
1303   ASSERT_EQ("../b/c", getPosixPath(std::string(It->path())));
1304 }
1305 
1306 TEST_F(InMemoryFileSystemTest, AddHardLinkToFile) {
1307   StringRef FromLink = "/path/to/FROM/link";
1308   StringRef Target = "/path/to/TO/file";
1309   FS.addFile(Target, 0, MemoryBuffer::getMemBuffer("content of target"));
1310   EXPECT_TRUE(FS.addHardLink(FromLink, Target));
1311   EXPECT_THAT(FromLink, IsHardLinkTo(&FS, Target));
1312   EXPECT_EQ(FS.status(FromLink)->getSize(), FS.status(Target)->getSize());
1313   EXPECT_EQ(FS.getBufferForFile(FromLink)->get()->getBuffer(),
1314             FS.getBufferForFile(Target)->get()->getBuffer());
1315 }
1316 
1317 TEST_F(InMemoryFileSystemTest, AddHardLinkInChainPattern) {
1318   StringRef Link0 = "/path/to/0/link";
1319   StringRef Link1 = "/path/to/1/link";
1320   StringRef Link2 = "/path/to/2/link";
1321   StringRef Target = "/path/to/target";
1322   FS.addFile(Target, 0, MemoryBuffer::getMemBuffer("content of target file"));
1323   EXPECT_TRUE(FS.addHardLink(Link2, Target));
1324   EXPECT_TRUE(FS.addHardLink(Link1, Link2));
1325   EXPECT_TRUE(FS.addHardLink(Link0, Link1));
1326   EXPECT_THAT(Link0, IsHardLinkTo(&FS, Target));
1327   EXPECT_THAT(Link1, IsHardLinkTo(&FS, Target));
1328   EXPECT_THAT(Link2, IsHardLinkTo(&FS, Target));
1329 }
1330 
1331 TEST_F(InMemoryFileSystemTest, AddHardLinkToAFileThatWasNotAddedBefore) {
1332   EXPECT_FALSE(FS.addHardLink("/path/to/link", "/path/to/target"));
1333 }
1334 
1335 TEST_F(InMemoryFileSystemTest, AddHardLinkFromAFileThatWasAddedBefore) {
1336   StringRef Link = "/path/to/link";
1337   StringRef Target = "/path/to/target";
1338   FS.addFile(Target, 0, MemoryBuffer::getMemBuffer("content of target"));
1339   FS.addFile(Link, 0, MemoryBuffer::getMemBuffer("content of link"));
1340   EXPECT_FALSE(FS.addHardLink(Link, Target));
1341 }
1342 
1343 TEST_F(InMemoryFileSystemTest, AddSameHardLinkMoreThanOnce) {
1344   StringRef Link = "/path/to/link";
1345   StringRef Target = "/path/to/target";
1346   FS.addFile(Target, 0, MemoryBuffer::getMemBuffer("content of target"));
1347   EXPECT_TRUE(FS.addHardLink(Link, Target));
1348   EXPECT_FALSE(FS.addHardLink(Link, Target));
1349 }
1350 
1351 TEST_F(InMemoryFileSystemTest, AddFileInPlaceOfAHardLinkWithSameContent) {
1352   StringRef Link = "/path/to/link";
1353   StringRef Target = "/path/to/target";
1354   StringRef Content = "content of target";
1355   EXPECT_TRUE(FS.addFile(Target, 0, MemoryBuffer::getMemBuffer(Content)));
1356   EXPECT_TRUE(FS.addHardLink(Link, Target));
1357   EXPECT_TRUE(FS.addFile(Link, 0, MemoryBuffer::getMemBuffer(Content)));
1358 }
1359 
1360 TEST_F(InMemoryFileSystemTest, AddFileInPlaceOfAHardLinkWithDifferentContent) {
1361   StringRef Link = "/path/to/link";
1362   StringRef Target = "/path/to/target";
1363   StringRef Content = "content of target";
1364   StringRef LinkContent = "different content of link";
1365   EXPECT_TRUE(FS.addFile(Target, 0, MemoryBuffer::getMemBuffer(Content)));
1366   EXPECT_TRUE(FS.addHardLink(Link, Target));
1367   EXPECT_FALSE(FS.addFile(Link, 0, MemoryBuffer::getMemBuffer(LinkContent)));
1368 }
1369 
1370 TEST_F(InMemoryFileSystemTest, AddHardLinkToADirectory) {
1371   StringRef Dir = "path/to/dummy/dir";
1372   StringRef Link = "/path/to/link";
1373   StringRef File = "path/to/dummy/dir/target";
1374   StringRef Content = "content of target";
1375   EXPECT_TRUE(FS.addFile(File, 0, MemoryBuffer::getMemBuffer(Content)));
1376   EXPECT_FALSE(FS.addHardLink(Link, Dir));
1377 }
1378 
1379 TEST_F(InMemoryFileSystemTest, AddHardLinkToASymlink) {
1380   EXPECT_TRUE(FS.addFile("/file", 0, MemoryBuffer::getMemBuffer("content")));
1381   EXPECT_TRUE(FS.addSymbolicLink("/symlink", "/file", 0));
1382   EXPECT_TRUE(FS.addHardLink("/hardlink", "/symlink"));
1383   EXPECT_EQ((*FS.getBufferForFile("/hardlink"))->getBuffer(), "content");
1384 }
1385 
1386 TEST_F(InMemoryFileSystemTest, AddHardLinkFromADirectory) {
1387   StringRef Dir = "path/to/dummy/dir";
1388   StringRef Target = "path/to/dummy/dir/target";
1389   StringRef Content = "content of target";
1390   EXPECT_TRUE(FS.addFile(Target, 0, MemoryBuffer::getMemBuffer(Content)));
1391   EXPECT_FALSE(FS.addHardLink(Dir, Target));
1392 }
1393 
1394 TEST_F(InMemoryFileSystemTest, AddHardLinkUnderAFile) {
1395   StringRef CommonContent = "content string";
1396   FS.addFile("/a/b", 0, MemoryBuffer::getMemBuffer(CommonContent));
1397   FS.addFile("/c/d", 0, MemoryBuffer::getMemBuffer(CommonContent));
1398   EXPECT_FALSE(FS.addHardLink("/c/d/e", "/a/b"));
1399 }
1400 
1401 TEST_F(InMemoryFileSystemTest, RecursiveIterationWithHardLink) {
1402   std::error_code EC;
1403   FS.addFile("/a/b", 0, MemoryBuffer::getMemBuffer("content string"));
1404   EXPECT_TRUE(FS.addHardLink("/c/d", "/a/b"));
1405   auto I = vfs::recursive_directory_iterator(FS, "/", EC);
1406   ASSERT_FALSE(EC);
1407   std::vector<std::string> Nodes;
1408   for (auto E = vfs::recursive_directory_iterator(); !EC && I != E;
1409        I.increment(EC)) {
1410     Nodes.push_back(getPosixPath(std::string(I->path())));
1411   }
1412   EXPECT_THAT(Nodes, testing::UnorderedElementsAre("/a", "/a/b", "/c", "/c/d"));
1413 }
1414 
1415 TEST_F(InMemoryFileSystemTest, UniqueID) {
1416   ASSERT_TRUE(FS.addFile("/a/b", 0, MemoryBuffer::getMemBuffer("text")));
1417   ASSERT_TRUE(FS.addFile("/c/d", 0, MemoryBuffer::getMemBuffer("text")));
1418   ASSERT_TRUE(FS.addHardLink("/e/f", "/a/b"));
1419 
1420   EXPECT_EQ(FS.status("/a/b")->getUniqueID(), FS.status("/a/b")->getUniqueID());
1421   EXPECT_NE(FS.status("/a/b")->getUniqueID(), FS.status("/c/d")->getUniqueID());
1422   EXPECT_EQ(FS.status("/a/b")->getUniqueID(), FS.status("/e/f")->getUniqueID());
1423   EXPECT_EQ(FS.status("/a")->getUniqueID(), FS.status("/a")->getUniqueID());
1424   EXPECT_NE(FS.status("/a")->getUniqueID(), FS.status("/c")->getUniqueID());
1425   EXPECT_NE(FS.status("/a")->getUniqueID(), FS.status("/e")->getUniqueID());
1426 
1427   // Recreating the "same" FS yields the same UniqueIDs.
1428   // Note: FS2 should match FS with respect to path normalization.
1429   vfs::InMemoryFileSystem FS2(/*UseNormalizedPath=*/false);
1430   ASSERT_TRUE(FS2.addFile("/a/b", 0, MemoryBuffer::getMemBuffer("text")));
1431   EXPECT_EQ(FS.status("/a/b")->getUniqueID(),
1432             FS2.status("/a/b")->getUniqueID());
1433   EXPECT_EQ(FS.status("/a")->getUniqueID(), FS2.status("/a")->getUniqueID());
1434 }
1435 
1436 TEST_F(InMemoryFileSystemTest, AddSymlinkToAFile) {
1437   EXPECT_TRUE(
1438       FS.addFile("/some/file", 0, MemoryBuffer::getMemBuffer("contents")));
1439   EXPECT_TRUE(FS.addSymbolicLink("/other/file/link", "/some/file", 0));
1440   ErrorOr<vfs::Status> Stat = FS.status("/some/file");
1441   EXPECT_TRUE(Stat->isRegularFile());
1442 }
1443 
1444 TEST_F(InMemoryFileSystemTest, AddSymlinkToADirectory) {
1445   EXPECT_TRUE(FS.addSymbolicLink("/link", "/target", 0));
1446   EXPECT_TRUE(
1447       FS.addFile("/target/foo.h", 0, MemoryBuffer::getMemBuffer("foo")));
1448   ErrorOr<vfs::Status> Stat = FS.status("/link/foo.h");
1449   EXPECT_TRUE(Stat);
1450   EXPECT_EQ((*Stat).getName(), "/link/foo.h");
1451   EXPECT_TRUE(Stat->isRegularFile());
1452 }
1453 
1454 TEST_F(InMemoryFileSystemTest, AddSymlinkToASymlink) {
1455   EXPECT_TRUE(FS.addSymbolicLink("/first", "/second", 0));
1456   EXPECT_TRUE(FS.addSymbolicLink("/second", "/third", 0));
1457   EXPECT_TRUE(FS.addFile("/third", 0, MemoryBuffer::getMemBuffer("")));
1458   ErrorOr<vfs::Status> Stat = FS.status("/first");
1459   EXPECT_TRUE(Stat);
1460   EXPECT_EQ((*Stat).getName(), "/first");
1461   // Follow-through symlinks by default. This matches RealFileSystem's
1462   // semantics.
1463   EXPECT_TRUE(Stat->isRegularFile());
1464   Stat = FS.status("/second");
1465   EXPECT_TRUE(Stat);
1466   EXPECT_EQ((*Stat).getName(), "/second");
1467   EXPECT_TRUE(Stat->isRegularFile());
1468   Stat = FS.status("/third");
1469   EXPECT_TRUE(Stat);
1470   EXPECT_EQ((*Stat).getName(), "/third");
1471   EXPECT_TRUE(Stat->isRegularFile());
1472 }
1473 
1474 TEST_F(InMemoryFileSystemTest, AddRecursiveSymlink) {
1475   EXPECT_TRUE(FS.addSymbolicLink("/link-a", "/link-b", 0));
1476   EXPECT_TRUE(FS.addSymbolicLink("/link-b", "/link-a", 0));
1477   ErrorOr<vfs::Status> Stat = FS.status("/link-a/foo");
1478   EXPECT_FALSE(Stat);
1479   EXPECT_EQ(Stat.getError(), errc::no_such_file_or_directory);
1480 }
1481 
1482 TEST_F(InMemoryFileSystemTest, DirectoryIteratorWithSymlinkToAFile) {
1483   std::error_code EC;
1484 
1485   EXPECT_TRUE(FS.addFile("/file", 0, MemoryBuffer::getMemBuffer("")));
1486   EXPECT_TRUE(FS.addSymbolicLink("/symlink", "/file", 0));
1487 
1488   vfs::directory_iterator I = FS.dir_begin("/", EC), E;
1489   ASSERT_FALSE(EC);
1490 
1491   std::vector<std::string> Nodes;
1492   for (; !EC && I != E; I.increment(EC))
1493     Nodes.push_back(getPosixPath(std::string(I->path())));
1494 
1495   EXPECT_THAT(Nodes, testing::UnorderedElementsAre("/file", "/file"));
1496 }
1497 
1498 TEST_F(InMemoryFileSystemTest, RecursiveDirectoryIteratorWithSymlinkToADir) {
1499   std::error_code EC;
1500 
1501   EXPECT_TRUE(FS.addFile("/dir/file", 0, MemoryBuffer::getMemBuffer("")));
1502   EXPECT_TRUE(FS.addSymbolicLink("/dir_symlink", "/dir", 0));
1503 
1504   vfs::recursive_directory_iterator I(FS, "/", EC), E;
1505   ASSERT_FALSE(EC);
1506 
1507   std::vector<std::string> Nodes;
1508   for (; !EC && I != E; I.increment(EC))
1509     Nodes.push_back(getPosixPath(std::string(I->path())));
1510 
1511   EXPECT_THAT(Nodes, testing::UnorderedElementsAre("/dir", "/dir/file", "/dir",
1512                                                    "/dir/file"));
1513 }
1514 
1515 // NOTE: in the tests below, we use '//root/' as our root directory, since it is
1516 // a legal *absolute* path on Windows as well as *nix.
1517 class VFSFromYAMLTest : public ::testing::Test {
1518 public:
1519   int NumDiagnostics;
1520 
1521   void SetUp() override { NumDiagnostics = 0; }
1522 
1523   static void CountingDiagHandler(const SMDiagnostic &, void *Context) {
1524     VFSFromYAMLTest *Test = static_cast<VFSFromYAMLTest *>(Context);
1525     ++Test->NumDiagnostics;
1526   }
1527 
1528   std::unique_ptr<vfs::FileSystem>
1529   getFromYAMLRawString(StringRef Content,
1530                        IntrusiveRefCntPtr<vfs::FileSystem> ExternalFS,
1531                        StringRef YAMLFilePath = "") {
1532     std::unique_ptr<MemoryBuffer> Buffer = MemoryBuffer::getMemBuffer(Content);
1533     return getVFSFromYAML(std::move(Buffer), CountingDiagHandler, YAMLFilePath,
1534                           this, ExternalFS);
1535   }
1536 
1537   std::unique_ptr<vfs::FileSystem> getFromYAMLString(
1538       StringRef Content,
1539       IntrusiveRefCntPtr<vfs::FileSystem> ExternalFS = new DummyFileSystem(),
1540       StringRef YAMLFilePath = "") {
1541     std::string VersionPlusContent("{\n  'version':0,\n");
1542     VersionPlusContent += Content.slice(Content.find('{') + 1, StringRef::npos);
1543     return getFromYAMLRawString(VersionPlusContent, ExternalFS, YAMLFilePath);
1544   }
1545 
1546   // This is intended as a "XFAIL" for windows hosts.
1547   bool supportsSameDirMultipleYAMLEntries() {
1548     Triple Host(Triple::normalize(sys::getProcessTriple()));
1549     return !Host.isOSWindows();
1550   }
1551 };
1552 
1553 TEST_F(VFSFromYAMLTest, BasicVFSFromYAML) {
1554   IntrusiveRefCntPtr<vfs::FileSystem> FS;
1555   FS = getFromYAMLString("");
1556   EXPECT_EQ(nullptr, FS.get());
1557   FS = getFromYAMLString("[]");
1558   EXPECT_EQ(nullptr, FS.get());
1559   FS = getFromYAMLString("'string'");
1560   EXPECT_EQ(nullptr, FS.get());
1561   EXPECT_EQ(3, NumDiagnostics);
1562 }
1563 
1564 TEST_F(VFSFromYAMLTest, MappedFiles) {
1565   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
1566   Lower->addDirectory("//root/foo/bar");
1567   Lower->addRegularFile("//root/foo/bar/a");
1568   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
1569       "{ 'roots': [\n"
1570       "{\n"
1571       "  'type': 'directory',\n"
1572       "  'name': '//root/',\n"
1573       "  'contents': [ {\n"
1574       "                  'type': 'file',\n"
1575       "                  'name': 'file1',\n"
1576       "                  'external-contents': '//root/foo/bar/a'\n"
1577       "                },\n"
1578       "                {\n"
1579       "                  'type': 'file',\n"
1580       "                  'name': 'file2',\n"
1581       "                  'external-contents': '//root/foo/b'\n"
1582       "                },\n"
1583       "                {\n"
1584       "                  'type': 'directory-remap',\n"
1585       "                  'name': 'mappeddir',\n"
1586       "                  'external-contents': '//root/foo/bar'\n"
1587       "                },\n"
1588       "                {\n"
1589       "                  'type': 'directory-remap',\n"
1590       "                  'name': 'mappeddir2',\n"
1591       "                  'use-external-name': false,\n"
1592       "                  'external-contents': '//root/foo/bar'\n"
1593       "                }\n"
1594       "              ]\n"
1595       "}\n"
1596       "]\n"
1597       "}",
1598       Lower);
1599   ASSERT_NE(FS.get(), nullptr);
1600 
1601   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
1602       new vfs::OverlayFileSystem(Lower));
1603   O->pushOverlay(FS);
1604 
1605   // file
1606   ErrorOr<vfs::Status> S = O->status("//root/file1");
1607   ASSERT_FALSE(S.getError());
1608   EXPECT_EQ("//root/foo/bar/a", S->getName());
1609   EXPECT_TRUE(S->ExposesExternalVFSPath);
1610 
1611   ErrorOr<vfs::Status> SLower = O->status("//root/foo/bar/a");
1612   EXPECT_EQ("//root/foo/bar/a", SLower->getName());
1613   EXPECT_TRUE(S->equivalent(*SLower));
1614   EXPECT_FALSE(SLower->ExposesExternalVFSPath);
1615 
1616   // file after opening
1617   auto OpenedF = O->openFileForRead("//root/file1");
1618   ASSERT_FALSE(OpenedF.getError());
1619   auto OpenedS = (*OpenedF)->status();
1620   ASSERT_FALSE(OpenedS.getError());
1621   EXPECT_EQ("//root/foo/bar/a", OpenedS->getName());
1622   EXPECT_TRUE(OpenedS->ExposesExternalVFSPath);
1623 
1624   // directory
1625   S = O->status("//root/");
1626   ASSERT_FALSE(S.getError());
1627   EXPECT_TRUE(S->isDirectory());
1628   EXPECT_TRUE(S->equivalent(*O->status("//root/"))); // non-volatile UniqueID
1629 
1630   // remapped directory
1631   S = O->status("//root/mappeddir");
1632   ASSERT_FALSE(S.getError());
1633   EXPECT_TRUE(S->isDirectory());
1634   EXPECT_TRUE(S->ExposesExternalVFSPath);
1635   EXPECT_TRUE(S->equivalent(*O->status("//root/foo/bar")));
1636 
1637   SLower = O->status("//root/foo/bar");
1638   EXPECT_EQ("//root/foo/bar", SLower->getName());
1639   EXPECT_TRUE(S->equivalent(*SLower));
1640   EXPECT_FALSE(SLower->ExposesExternalVFSPath);
1641 
1642   // file in remapped directory
1643   S = O->status("//root/mappeddir/a");
1644   ASSERT_FALSE(S.getError());
1645   EXPECT_FALSE(S->isDirectory());
1646   EXPECT_TRUE(S->ExposesExternalVFSPath);
1647   EXPECT_EQ("//root/foo/bar/a", S->getName());
1648 
1649   // file in remapped directory, with use-external-name=false
1650   S = O->status("//root/mappeddir2/a");
1651   ASSERT_FALSE(S.getError());
1652   EXPECT_FALSE(S->isDirectory());
1653   EXPECT_FALSE(S->ExposesExternalVFSPath);
1654   EXPECT_EQ("//root/mappeddir2/a", S->getName());
1655 
1656   // file contents in remapped directory
1657   OpenedF = O->openFileForRead("//root/mappeddir/a");
1658   ASSERT_FALSE(OpenedF.getError());
1659   OpenedS = (*OpenedF)->status();
1660   ASSERT_FALSE(OpenedS.getError());
1661   EXPECT_EQ("//root/foo/bar/a", OpenedS->getName());
1662   EXPECT_TRUE(OpenedS->ExposesExternalVFSPath);
1663 
1664   // file contents in remapped directory, with use-external-name=false
1665   OpenedF = O->openFileForRead("//root/mappeddir2/a");
1666   ASSERT_FALSE(OpenedF.getError());
1667   OpenedS = (*OpenedF)->status();
1668   ASSERT_FALSE(OpenedS.getError());
1669   EXPECT_EQ("//root/mappeddir2/a", OpenedS->getName());
1670   EXPECT_FALSE(OpenedS->ExposesExternalVFSPath);
1671 
1672   // broken mapping
1673   EXPECT_EQ(O->status("//root/file2").getError(),
1674             llvm::errc::no_such_file_or_directory);
1675   EXPECT_EQ(0, NumDiagnostics);
1676 }
1677 
1678 TEST_F(VFSFromYAMLTest, MappedRoot) {
1679   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
1680   Lower->addDirectory("//root/foo/bar");
1681   Lower->addRegularFile("//root/foo/bar/a");
1682   IntrusiveRefCntPtr<vfs::FileSystem> FS =
1683       getFromYAMLString("{ 'roots': [\n"
1684                         "{\n"
1685                         "  'type': 'directory-remap',\n"
1686                         "  'name': '//mappedroot/',\n"
1687                         "  'external-contents': '//root/foo/bar'\n"
1688                         "}\n"
1689                         "]\n"
1690                         "}",
1691                         Lower);
1692   ASSERT_NE(FS.get(), nullptr);
1693 
1694   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
1695       new vfs::OverlayFileSystem(Lower));
1696   O->pushOverlay(FS);
1697 
1698   // file
1699   ErrorOr<vfs::Status> S = O->status("//mappedroot/a");
1700   ASSERT_FALSE(S.getError());
1701   EXPECT_EQ("//root/foo/bar/a", S->getName());
1702   EXPECT_TRUE(S->ExposesExternalVFSPath);
1703 
1704   ErrorOr<vfs::Status> SLower = O->status("//root/foo/bar/a");
1705   EXPECT_EQ("//root/foo/bar/a", SLower->getName());
1706   EXPECT_TRUE(S->equivalent(*SLower));
1707   EXPECT_FALSE(SLower->ExposesExternalVFSPath);
1708 
1709   // file after opening
1710   auto OpenedF = O->openFileForRead("//mappedroot/a");
1711   ASSERT_FALSE(OpenedF.getError());
1712   auto OpenedS = (*OpenedF)->status();
1713   ASSERT_FALSE(OpenedS.getError());
1714   EXPECT_EQ("//root/foo/bar/a", OpenedS->getName());
1715   EXPECT_TRUE(OpenedS->ExposesExternalVFSPath);
1716 
1717   EXPECT_EQ(0, NumDiagnostics);
1718 }
1719 
1720 TEST_F(VFSFromYAMLTest, RemappedDirectoryOverlay) {
1721   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
1722   Lower->addDirectory("//root/foo");
1723   Lower->addRegularFile("//root/foo/a");
1724   Lower->addDirectory("//root/bar");
1725   Lower->addRegularFile("//root/bar/b");
1726   Lower->addRegularFile("//root/bar/c");
1727   IntrusiveRefCntPtr<vfs::FileSystem> FS =
1728       getFromYAMLString("{ 'roots': [\n"
1729                         "{\n"
1730                         "  'type': 'directory',\n"
1731                         "  'name': '//root/',\n"
1732                         "  'contents': [ {\n"
1733                         "                  'type': 'directory-remap',\n"
1734                         "                  'name': 'bar',\n"
1735                         "                  'external-contents': '//root/foo'\n"
1736                         "                }\n"
1737                         "              ]\n"
1738                         "}]}",
1739                         Lower);
1740   ASSERT_NE(FS.get(), nullptr);
1741 
1742   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
1743       new vfs::OverlayFileSystem(Lower));
1744   O->pushOverlay(FS);
1745 
1746   ErrorOr<vfs::Status> S = O->status("//root/foo");
1747   ASSERT_FALSE(S.getError());
1748 
1749   ErrorOr<vfs::Status> SS = O->status("//root/bar");
1750   ASSERT_FALSE(SS.getError());
1751   EXPECT_TRUE(S->equivalent(*SS));
1752 
1753   std::error_code EC;
1754   checkContents(O->dir_begin("//root/bar", EC),
1755                 {"//root/foo/a", "//root/bar/b", "//root/bar/c"});
1756 
1757   Lower->addRegularFile("//root/foo/b");
1758   checkContents(O->dir_begin("//root/bar", EC),
1759                 {"//root/foo/a", "//root/foo/b", "//root/bar/c"});
1760 
1761   EXPECT_EQ(0, NumDiagnostics);
1762 }
1763 
1764 TEST_F(VFSFromYAMLTest, RemappedDirectoryOverlayNoExternalNames) {
1765   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
1766   Lower->addDirectory("//root/foo");
1767   Lower->addRegularFile("//root/foo/a");
1768   Lower->addDirectory("//root/bar");
1769   Lower->addRegularFile("//root/bar/b");
1770   Lower->addRegularFile("//root/bar/c");
1771   IntrusiveRefCntPtr<vfs::FileSystem> FS =
1772       getFromYAMLString("{ 'use-external-names': false,\n"
1773                         "  'roots': [\n"
1774                         "{\n"
1775                         "  'type': 'directory',\n"
1776                         "  'name': '//root/',\n"
1777                         "  'contents': [ {\n"
1778                         "                  'type': 'directory-remap',\n"
1779                         "                  'name': 'bar',\n"
1780                         "                  'external-contents': '//root/foo'\n"
1781                         "                }\n"
1782                         "              ]\n"
1783                         "}]}",
1784                         Lower);
1785   ASSERT_NE(FS.get(), nullptr);
1786 
1787   ErrorOr<vfs::Status> S = FS->status("//root/foo");
1788   ASSERT_FALSE(S.getError());
1789 
1790   ErrorOr<vfs::Status> SS = FS->status("//root/bar");
1791   ASSERT_FALSE(SS.getError());
1792   EXPECT_TRUE(S->equivalent(*SS));
1793 
1794   std::error_code EC;
1795   checkContents(FS->dir_begin("//root/bar", EC),
1796                 {"//root/bar/a", "//root/bar/b", "//root/bar/c"});
1797 
1798   Lower->addRegularFile("//root/foo/b");
1799   checkContents(FS->dir_begin("//root/bar", EC),
1800                 {"//root/bar/a", "//root/bar/b", "//root/bar/c"});
1801 
1802   EXPECT_EQ(0, NumDiagnostics);
1803 }
1804 
1805 TEST_F(VFSFromYAMLTest, RemappedDirectoryOverlayNoFallthrough) {
1806   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
1807   Lower->addDirectory("//root/foo");
1808   Lower->addRegularFile("//root/foo/a");
1809   Lower->addDirectory("//root/bar");
1810   Lower->addRegularFile("//root/bar/b");
1811   Lower->addRegularFile("//root/bar/c");
1812   IntrusiveRefCntPtr<vfs::FileSystem> FS =
1813       getFromYAMLString("{ 'fallthrough': false,\n"
1814                         "  'roots': [\n"
1815                         "{\n"
1816                         "  'type': 'directory',\n"
1817                         "  'name': '//root/',\n"
1818                         "  'contents': [ {\n"
1819                         "                  'type': 'directory-remap',\n"
1820                         "                  'name': 'bar',\n"
1821                         "                  'external-contents': '//root/foo'\n"
1822                         "                }\n"
1823                         "              ]\n"
1824                         "}]}",
1825                         Lower);
1826   ASSERT_NE(FS.get(), nullptr);
1827 
1828   ErrorOr<vfs::Status> S = Lower->status("//root/foo");
1829   ASSERT_FALSE(S.getError());
1830 
1831   ErrorOr<vfs::Status> SS = FS->status("//root/bar");
1832   ASSERT_FALSE(SS.getError());
1833   EXPECT_TRUE(S->equivalent(*SS));
1834 
1835   std::error_code EC;
1836   checkContents(FS->dir_begin("//root/bar", EC), {"//root/foo/a"});
1837 
1838   Lower->addRegularFile("//root/foo/b");
1839   checkContents(FS->dir_begin("//root/bar", EC),
1840                 {"//root/foo/a", "//root/foo/b"});
1841 
1842   EXPECT_EQ(0, NumDiagnostics);
1843 }
1844 
1845 TEST_F(VFSFromYAMLTest, ReturnsRequestedPathVFSMiss) {
1846   IntrusiveRefCntPtr<vfs::InMemoryFileSystem> BaseFS(
1847       new vfs::InMemoryFileSystem);
1848   BaseFS->addFile("//root/foo/a", 0,
1849                   MemoryBuffer::getMemBuffer("contents of a"));
1850   ASSERT_FALSE(BaseFS->setCurrentWorkingDirectory("//root/foo"));
1851   auto RemappedFS = vfs::RedirectingFileSystem::create(
1852       {}, /*UseExternalNames=*/false, *BaseFS);
1853 
1854   auto OpenedF = RemappedFS->openFileForRead("a");
1855   ASSERT_FALSE(OpenedF.getError());
1856   llvm::ErrorOr<std::string> Name = (*OpenedF)->getName();
1857   ASSERT_FALSE(Name.getError());
1858   EXPECT_EQ("a", Name.get());
1859 
1860   auto OpenedS = (*OpenedF)->status();
1861   ASSERT_FALSE(OpenedS.getError());
1862   EXPECT_EQ("a", OpenedS->getName());
1863   EXPECT_FALSE(OpenedS->ExposesExternalVFSPath);
1864 
1865   auto DirectS = RemappedFS->status("a");
1866   ASSERT_FALSE(DirectS.getError());
1867   EXPECT_EQ("a", DirectS->getName());
1868   EXPECT_FALSE(DirectS->ExposesExternalVFSPath);
1869 
1870   EXPECT_EQ(0, NumDiagnostics);
1871 }
1872 
1873 TEST_F(VFSFromYAMLTest, ReturnsExternalPathVFSHit) {
1874   IntrusiveRefCntPtr<vfs::InMemoryFileSystem> BaseFS(
1875       new vfs::InMemoryFileSystem);
1876   BaseFS->addFile("//root/foo/realname", 0,
1877                   MemoryBuffer::getMemBuffer("contents of a"));
1878   auto FS =
1879       getFromYAMLString("{ 'use-external-names': true,\n"
1880                         "  'roots': [\n"
1881                         "{\n"
1882                         "  'type': 'directory',\n"
1883                         "  'name': '//root/foo',\n"
1884                         "  'contents': [ {\n"
1885                         "                  'type': 'file',\n"
1886                         "                  'name': 'vfsname',\n"
1887                         "                  'external-contents': 'realname'\n"
1888                         "                }\n"
1889                         "              ]\n"
1890                         "}]}",
1891                         BaseFS);
1892   ASSERT_FALSE(FS->setCurrentWorkingDirectory("//root/foo"));
1893 
1894   auto OpenedF = FS->openFileForRead("vfsname");
1895   ASSERT_FALSE(OpenedF.getError());
1896   llvm::ErrorOr<std::string> Name = (*OpenedF)->getName();
1897   ASSERT_FALSE(Name.getError());
1898   EXPECT_EQ("realname", Name.get());
1899 
1900   auto OpenedS = (*OpenedF)->status();
1901   ASSERT_FALSE(OpenedS.getError());
1902   EXPECT_EQ("realname", OpenedS->getName());
1903   EXPECT_TRUE(OpenedS->ExposesExternalVFSPath);
1904 
1905   auto DirectS = FS->status("vfsname");
1906   ASSERT_FALSE(DirectS.getError());
1907   EXPECT_EQ("realname", DirectS->getName());
1908   EXPECT_TRUE(DirectS->ExposesExternalVFSPath);
1909 
1910   EXPECT_EQ(0, NumDiagnostics);
1911 }
1912 
1913 TEST_F(VFSFromYAMLTest, RootRelativeTest) {
1914   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
1915   Lower->addDirectory("//root/foo/bar");
1916   Lower->addRegularFile("//root/foo/bar/a");
1917   IntrusiveRefCntPtr<vfs::FileSystem> FS =
1918       getFromYAMLString("{\n"
1919                         "  'case-sensitive': false,\n"
1920                         "  'root-relative': 'overlay-dir',\n"
1921                         "  'roots': [\n"
1922                         "    { 'name': 'b', 'type': 'file',\n"
1923                         "      'external-contents': '//root/foo/bar/a'\n"
1924                         "    }\n"
1925                         "  ]\n"
1926                         "}",
1927                         Lower, "//root/foo/bar/overlay");
1928 
1929   ASSERT_NE(FS.get(), nullptr);
1930   ErrorOr<vfs::Status> S = FS->status("//root/foo/bar/b");
1931   ASSERT_FALSE(S.getError());
1932   EXPECT_EQ("//root/foo/bar/a", S->getName());
1933 
1934   // On Windows, with overlay-relative set to true, the relative
1935   // path in external-contents field will be prepend by OverlayDir
1936   // with native path separator, regardless of the actual path separator
1937   // used in YAMLFilePath field.
1938 #ifndef _WIN32
1939   FS = getFromYAMLString("{\n"
1940                          "  'case-sensitive': false,\n"
1941                          "  'overlay-relative': true,\n"
1942                          "  'root-relative': 'overlay-dir',\n"
1943                          "  'roots': [\n"
1944                          "    { 'name': 'b', 'type': 'file',\n"
1945                          "      'external-contents': 'a'\n"
1946                          "    }\n"
1947                          "  ]\n"
1948                          "}",
1949                          Lower, "//root/foo/bar/overlay");
1950   ASSERT_NE(FS.get(), nullptr);
1951   S = FS->status("//root/foo/bar/b");
1952   ASSERT_FALSE(S.getError());
1953   EXPECT_EQ("//root/foo/bar/a", S->getName());
1954 #else
1955   IntrusiveRefCntPtr<DummyFileSystem> LowerWindows(new DummyFileSystem());
1956   LowerWindows->addDirectory("\\\\root\\foo\\bar");
1957   LowerWindows->addRegularFile("\\\\root\\foo\\bar\\a");
1958   FS = getFromYAMLString("{\n"
1959                          "  'case-sensitive': false,\n"
1960                          "  'overlay-relative': true,\n"
1961                          "  'root-relative': 'overlay-dir',\n"
1962                          "  'roots': [\n"
1963                          "    { 'name': 'b', 'type': 'file',\n"
1964                          "      'external-contents': 'a'\n"
1965                          "    }\n"
1966                          "  ]\n"
1967                          "}",
1968                          LowerWindows, "\\\\root\\foo\\bar\\overlay");
1969   ASSERT_NE(FS.get(), nullptr);
1970   S = FS->status("\\\\root\\foo\\bar\\b");
1971   ASSERT_FALSE(S.getError());
1972   EXPECT_EQ("\\\\root\\foo\\bar\\a", S->getName());
1973 #endif
1974 }
1975 
1976 TEST_F(VFSFromYAMLTest, ReturnsInternalPathVFSHit) {
1977   IntrusiveRefCntPtr<vfs::InMemoryFileSystem> BaseFS(
1978       new vfs::InMemoryFileSystem);
1979   BaseFS->addFile("//root/foo/realname", 0,
1980                   MemoryBuffer::getMemBuffer("contents of a"));
1981   auto FS =
1982       getFromYAMLString("{ 'use-external-names': false,\n"
1983                         "  'roots': [\n"
1984                         "{\n"
1985                         "  'type': 'directory',\n"
1986                         "  'name': '//root/foo',\n"
1987                         "  'contents': [ {\n"
1988                         "                  'type': 'file',\n"
1989                         "                  'name': 'vfsname',\n"
1990                         "                  'external-contents': 'realname'\n"
1991                         "                }\n"
1992                         "              ]\n"
1993                         "}]}",
1994                         BaseFS);
1995   ASSERT_FALSE(FS->setCurrentWorkingDirectory("//root/foo"));
1996 
1997   auto OpenedF = FS->openFileForRead("vfsname");
1998   ASSERT_FALSE(OpenedF.getError());
1999   llvm::ErrorOr<std::string> Name = (*OpenedF)->getName();
2000   ASSERT_FALSE(Name.getError());
2001   EXPECT_EQ("vfsname", Name.get());
2002 
2003   auto OpenedS = (*OpenedF)->status();
2004   ASSERT_FALSE(OpenedS.getError());
2005   EXPECT_EQ("vfsname", OpenedS->getName());
2006   EXPECT_FALSE(OpenedS->ExposesExternalVFSPath);
2007 
2008   auto DirectS = FS->status("vfsname");
2009   ASSERT_FALSE(DirectS.getError());
2010   EXPECT_EQ("vfsname", DirectS->getName());
2011   EXPECT_FALSE(DirectS->ExposesExternalVFSPath);
2012 
2013   EXPECT_EQ(0, NumDiagnostics);
2014 }
2015 
2016 TEST_F(VFSFromYAMLTest, CaseInsensitive) {
2017   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2018   Lower->addRegularFile("//root/foo/bar/a");
2019   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2020       "{ 'case-sensitive': 'false',\n"
2021       "  'roots': [\n"
2022       "{\n"
2023       "  'type': 'directory',\n"
2024       "  'name': '//root/',\n"
2025       "  'contents': [ {\n"
2026       "                  'type': 'file',\n"
2027       "                  'name': 'XX',\n"
2028       "                  'external-contents': '//root/foo/bar/a'\n"
2029       "                }\n"
2030       "              ]\n"
2031       "}]}",
2032       Lower);
2033   ASSERT_NE(FS.get(), nullptr);
2034 
2035   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
2036       new vfs::OverlayFileSystem(Lower));
2037   O->pushOverlay(FS);
2038 
2039   ErrorOr<vfs::Status> S = O->status("//root/XX");
2040   ASSERT_FALSE(S.getError());
2041 
2042   ErrorOr<vfs::Status> SS = O->status("//root/xx");
2043   ASSERT_FALSE(SS.getError());
2044   EXPECT_TRUE(S->equivalent(*SS));
2045   SS = O->status("//root/xX");
2046   EXPECT_TRUE(S->equivalent(*SS));
2047   SS = O->status("//root/Xx");
2048   EXPECT_TRUE(S->equivalent(*SS));
2049   EXPECT_EQ(0, NumDiagnostics);
2050 }
2051 
2052 TEST_F(VFSFromYAMLTest, CaseSensitive) {
2053   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2054   Lower->addRegularFile("//root/foo/bar/a");
2055   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2056       "{ 'case-sensitive': 'true',\n"
2057       "  'roots': [\n"
2058       "{\n"
2059       "  'type': 'directory',\n"
2060       "  'name': '//root/',\n"
2061       "  'contents': [ {\n"
2062       "                  'type': 'file',\n"
2063       "                  'name': 'XX',\n"
2064       "                  'external-contents': '//root/foo/bar/a'\n"
2065       "                }\n"
2066       "              ]\n"
2067       "}]}",
2068       Lower);
2069   ASSERT_NE(FS.get(), nullptr);
2070 
2071   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
2072       new vfs::OverlayFileSystem(Lower));
2073   O->pushOverlay(FS);
2074 
2075   ErrorOr<vfs::Status> SS = O->status("//root/xx");
2076   EXPECT_EQ(SS.getError(), llvm::errc::no_such_file_or_directory);
2077   SS = O->status("//root/xX");
2078   EXPECT_EQ(SS.getError(), llvm::errc::no_such_file_or_directory);
2079   SS = O->status("//root/Xx");
2080   EXPECT_EQ(SS.getError(), llvm::errc::no_such_file_or_directory);
2081   EXPECT_EQ(0, NumDiagnostics);
2082 }
2083 
2084 TEST_F(VFSFromYAMLTest, IllegalVFSFile) {
2085   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2086 
2087   // invalid YAML at top-level
2088   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString("{]", Lower);
2089   EXPECT_EQ(nullptr, FS.get());
2090   // invalid YAML in roots
2091   FS = getFromYAMLString("{ 'roots':[}", Lower);
2092   // invalid YAML in directory
2093   FS = getFromYAMLString(
2094       "{ 'roots':[ { 'name': 'foo', 'type': 'directory', 'contents': [}",
2095       Lower);
2096   EXPECT_EQ(nullptr, FS.get());
2097 
2098   // invalid configuration
2099   FS = getFromYAMLString("{ 'knobular': 'true', 'roots':[] }", Lower);
2100   EXPECT_EQ(nullptr, FS.get());
2101   FS = getFromYAMLString("{ 'case-sensitive': 'maybe', 'roots':[] }", Lower);
2102   EXPECT_EQ(nullptr, FS.get());
2103 
2104   // invalid roots
2105   FS = getFromYAMLString("{ 'roots':'' }", Lower);
2106   EXPECT_EQ(nullptr, FS.get());
2107   FS = getFromYAMLString("{ 'roots':{} }", Lower);
2108   EXPECT_EQ(nullptr, FS.get());
2109 
2110   // invalid entries
2111   FS = getFromYAMLString(
2112       "{ 'roots':[ { 'type': 'other', 'name': 'me', 'contents': '' }", Lower);
2113   EXPECT_EQ(nullptr, FS.get());
2114   FS = getFromYAMLString("{ 'roots':[ { 'type': 'file', 'name': [], "
2115                          "'external-contents': 'other' }",
2116                          Lower);
2117   EXPECT_EQ(nullptr, FS.get());
2118   FS = getFromYAMLString(
2119       "{ 'roots':[ { 'type': 'file', 'name': 'me', 'external-contents': [] }",
2120       Lower);
2121   EXPECT_EQ(nullptr, FS.get());
2122   FS = getFromYAMLString(
2123       "{ 'roots':[ { 'type': 'file', 'name': 'me', 'external-contents': {} }",
2124       Lower);
2125   EXPECT_EQ(nullptr, FS.get());
2126   FS = getFromYAMLString(
2127       "{ 'roots':[ { 'type': 'directory', 'name': 'me', 'contents': {} }",
2128       Lower);
2129   EXPECT_EQ(nullptr, FS.get());
2130   FS = getFromYAMLString(
2131       "{ 'roots':[ { 'type': 'directory', 'name': 'me', 'contents': '' }",
2132       Lower);
2133   EXPECT_EQ(nullptr, FS.get());
2134   FS = getFromYAMLString(
2135       "{ 'roots':[ { 'thingy': 'directory', 'name': 'me', 'contents': [] }",
2136       Lower);
2137   EXPECT_EQ(nullptr, FS.get());
2138 
2139   // missing mandatory fields
2140   FS = getFromYAMLString("{ 'roots':[ { 'type': 'file', 'name': 'me' }", Lower);
2141   EXPECT_EQ(nullptr, FS.get());
2142   FS = getFromYAMLString(
2143       "{ 'roots':[ { 'type': 'file', 'external-contents': 'other' }", Lower);
2144   EXPECT_EQ(nullptr, FS.get());
2145   FS = getFromYAMLString("{ 'roots':[ { 'name': 'me', 'contents': [] }", Lower);
2146   EXPECT_EQ(nullptr, FS.get());
2147 
2148   // duplicate keys
2149   FS = getFromYAMLString("{ 'roots':[], 'roots':[] }", Lower);
2150   EXPECT_EQ(nullptr, FS.get());
2151   FS = getFromYAMLString(
2152       "{ 'case-sensitive':'true', 'case-sensitive':'true', 'roots':[] }",
2153       Lower);
2154   EXPECT_EQ(nullptr, FS.get());
2155   FS =
2156       getFromYAMLString("{ 'roots':[{'name':'me', 'name':'you', 'type':'file', "
2157                         "'external-contents':'blah' } ] }",
2158                         Lower);
2159   EXPECT_EQ(nullptr, FS.get());
2160 
2161   // missing version
2162   FS = getFromYAMLRawString("{ 'roots':[] }", Lower);
2163   EXPECT_EQ(nullptr, FS.get());
2164 
2165   // bad version number
2166   FS = getFromYAMLRawString("{ 'version':'foo', 'roots':[] }", Lower);
2167   EXPECT_EQ(nullptr, FS.get());
2168   FS = getFromYAMLRawString("{ 'version':-1, 'roots':[] }", Lower);
2169   EXPECT_EQ(nullptr, FS.get());
2170   FS = getFromYAMLRawString("{ 'version':100000, 'roots':[] }", Lower);
2171   EXPECT_EQ(nullptr, FS.get());
2172 
2173   // both 'external-contents' and 'contents' specified
2174   Lower->addDirectory("//root/external/dir");
2175   FS = getFromYAMLString(
2176       "{ 'roots':[ \n"
2177       "{ 'type': 'directory', 'name': '//root/A', 'contents': [],\n"
2178       "  'external-contents': '//root/external/dir'}]}",
2179       Lower);
2180   EXPECT_EQ(nullptr, FS.get());
2181 
2182   // 'directory-remap' with 'contents'
2183   FS = getFromYAMLString(
2184       "{ 'roots':[ \n"
2185       "{ 'type': 'directory-remap', 'name': '//root/A', 'contents': [] }]}",
2186       Lower);
2187   EXPECT_EQ(nullptr, FS.get());
2188 
2189   // invalid redirect kind
2190   FS = getFromYAMLString("{ 'redirecting-with': 'none', 'roots': [{\n"
2191                          "  'type': 'directory-remap',\n"
2192                          "  'name': '//root/A',\n"
2193                          "  'external-contents': '//root/B' }]}",
2194                          Lower);
2195   EXPECT_EQ(nullptr, FS.get());
2196 
2197   // redirect and fallthrough passed
2198   FS = getFromYAMLString("{ 'redirecting-with': 'fallthrough',\n"
2199                          "  'fallthrough': true,\n"
2200                          "  'roots': [{\n"
2201                          "    'type': 'directory-remap',\n"
2202                          "    'name': '//root/A',\n"
2203                          "    'external-contents': '//root/B' }]}",
2204                          Lower);
2205   EXPECT_EQ(nullptr, FS.get());
2206 
2207   EXPECT_EQ(28, NumDiagnostics);
2208 }
2209 
2210 TEST_F(VFSFromYAMLTest, UseExternalName) {
2211   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2212   Lower->addRegularFile("//root/external/file");
2213 
2214   IntrusiveRefCntPtr<vfs::FileSystem> FS =
2215       getFromYAMLString("{ 'roots': [\n"
2216                         "  { 'type': 'file', 'name': '//root/A',\n"
2217                         "    'external-contents': '//root/external/file'\n"
2218                         "  },\n"
2219                         "  { 'type': 'file', 'name': '//root/B',\n"
2220                         "    'use-external-name': true,\n"
2221                         "    'external-contents': '//root/external/file'\n"
2222                         "  },\n"
2223                         "  { 'type': 'file', 'name': '//root/C',\n"
2224                         "    'use-external-name': false,\n"
2225                         "    'external-contents': '//root/external/file'\n"
2226                         "  }\n"
2227                         "] }",
2228                         Lower);
2229   ASSERT_NE(nullptr, FS.get());
2230 
2231   // default true
2232   EXPECT_EQ("//root/external/file", FS->status("//root/A")->getName());
2233   // explicit
2234   EXPECT_EQ("//root/external/file", FS->status("//root/B")->getName());
2235   EXPECT_EQ("//root/C", FS->status("//root/C")->getName());
2236 
2237   // global configuration
2238   FS = getFromYAMLString("{ 'use-external-names': false,\n"
2239                          "  'roots': [\n"
2240                          "  { 'type': 'file', 'name': '//root/A',\n"
2241                          "    'external-contents': '//root/external/file'\n"
2242                          "  },\n"
2243                          "  { 'type': 'file', 'name': '//root/B',\n"
2244                          "    'use-external-name': true,\n"
2245                          "    'external-contents': '//root/external/file'\n"
2246                          "  },\n"
2247                          "  { 'type': 'file', 'name': '//root/C',\n"
2248                          "    'use-external-name': false,\n"
2249                          "    'external-contents': '//root/external/file'\n"
2250                          "  }\n"
2251                          "] }",
2252                          Lower);
2253   ASSERT_NE(nullptr, FS.get());
2254 
2255   // default
2256   EXPECT_EQ("//root/A", FS->status("//root/A")->getName());
2257   // explicit
2258   EXPECT_EQ("//root/external/file", FS->status("//root/B")->getName());
2259   EXPECT_EQ("//root/C", FS->status("//root/C")->getName());
2260 }
2261 
2262 TEST_F(VFSFromYAMLTest, MultiComponentPath) {
2263   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2264   Lower->addRegularFile("//root/other");
2265 
2266   // file in roots
2267   IntrusiveRefCntPtr<vfs::FileSystem> FS =
2268       getFromYAMLString("{ 'roots': [\n"
2269                         "  { 'type': 'file', 'name': '//root/path/to/file',\n"
2270                         "    'external-contents': '//root/other' }]\n"
2271                         "}",
2272                         Lower);
2273   ASSERT_NE(nullptr, FS.get());
2274   EXPECT_FALSE(FS->status("//root/path/to/file").getError());
2275   EXPECT_FALSE(FS->status("//root/path/to").getError());
2276   EXPECT_FALSE(FS->status("//root/path").getError());
2277   EXPECT_FALSE(FS->status("//root/").getError());
2278 
2279   // at the start
2280   FS = getFromYAMLString(
2281       "{ 'roots': [\n"
2282       "  { 'type': 'directory', 'name': '//root/path/to',\n"
2283       "    'contents': [ { 'type': 'file', 'name': 'file',\n"
2284       "                    'external-contents': '//root/other' }]}]\n"
2285       "}",
2286       Lower);
2287   ASSERT_NE(nullptr, FS.get());
2288   EXPECT_FALSE(FS->status("//root/path/to/file").getError());
2289   EXPECT_FALSE(FS->status("//root/path/to").getError());
2290   EXPECT_FALSE(FS->status("//root/path").getError());
2291   EXPECT_FALSE(FS->status("//root/").getError());
2292 
2293   // at the end
2294   FS = getFromYAMLString(
2295       "{ 'roots': [\n"
2296       "  { 'type': 'directory', 'name': '//root/',\n"
2297       "    'contents': [ { 'type': 'file', 'name': 'path/to/file',\n"
2298       "                    'external-contents': '//root/other' }]}]\n"
2299       "}",
2300       Lower);
2301   ASSERT_NE(nullptr, FS.get());
2302   EXPECT_FALSE(FS->status("//root/path/to/file").getError());
2303   EXPECT_FALSE(FS->status("//root/path/to").getError());
2304   EXPECT_FALSE(FS->status("//root/path").getError());
2305   EXPECT_FALSE(FS->status("//root/").getError());
2306 }
2307 
2308 TEST_F(VFSFromYAMLTest, TrailingSlashes) {
2309   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2310   Lower->addRegularFile("//root/other");
2311 
2312   // file in roots
2313   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2314       "{ 'roots': [\n"
2315       "  { 'type': 'directory', 'name': '//root/path/to////',\n"
2316       "    'contents': [ { 'type': 'file', 'name': 'file',\n"
2317       "                    'external-contents': '//root/other' }]}]\n"
2318       "}",
2319       Lower);
2320   ASSERT_NE(nullptr, FS.get());
2321   EXPECT_FALSE(FS->status("//root/path/to/file").getError());
2322   EXPECT_FALSE(FS->status("//root/path/to").getError());
2323   EXPECT_FALSE(FS->status("//root/path").getError());
2324   EXPECT_FALSE(FS->status("//root/").getError());
2325 }
2326 
2327 TEST_F(VFSFromYAMLTest, DirectoryIteration) {
2328   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2329   Lower->addDirectory("//root/");
2330   Lower->addDirectory("//root/foo");
2331   Lower->addDirectory("//root/foo/bar");
2332   Lower->addRegularFile("//root/foo/bar/a");
2333   Lower->addRegularFile("//root/foo/bar/b");
2334   Lower->addRegularFile("//root/file3");
2335   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2336       "{ 'use-external-names': false,\n"
2337       "  'roots': [\n"
2338       "{\n"
2339       "  'type': 'directory',\n"
2340       "  'name': '//root/',\n"
2341       "  'contents': [ {\n"
2342       "                  'type': 'file',\n"
2343       "                  'name': 'file1',\n"
2344       "                  'external-contents': '//root/foo/bar/a'\n"
2345       "                },\n"
2346       "                {\n"
2347       "                  'type': 'file',\n"
2348       "                  'name': 'file2',\n"
2349       "                  'external-contents': '//root/foo/bar/b'\n"
2350       "                }\n"
2351       "              ]\n"
2352       "}\n"
2353       "]\n"
2354       "}",
2355       Lower);
2356   ASSERT_NE(FS.get(), nullptr);
2357 
2358   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
2359       new vfs::OverlayFileSystem(Lower));
2360   O->pushOverlay(FS);
2361 
2362   std::error_code EC;
2363   checkContents(O->dir_begin("//root/", EC),
2364                 {"//root/file1", "//root/file2", "//root/file3", "//root/foo"});
2365 
2366   checkContents(O->dir_begin("//root/foo/bar", EC),
2367                 {"//root/foo/bar/a", "//root/foo/bar/b"});
2368 }
2369 
2370 TEST_F(VFSFromYAMLTest, DirectoryIterationSameDirMultipleEntries) {
2371   // https://llvm.org/bugs/show_bug.cgi?id=27725
2372   if (!supportsSameDirMultipleYAMLEntries())
2373     GTEST_SKIP();
2374 
2375   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2376   Lower->addDirectory("//root/zab");
2377   Lower->addDirectory("//root/baz");
2378   Lower->addRegularFile("//root/zab/a");
2379   Lower->addRegularFile("//root/zab/b");
2380   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2381       "{ 'use-external-names': false,\n"
2382       "  'roots': [\n"
2383       "{\n"
2384       "  'type': 'directory',\n"
2385       "  'name': '//root/baz/',\n"
2386       "  'contents': [ {\n"
2387       "                  'type': 'file',\n"
2388       "                  'name': 'x',\n"
2389       "                  'external-contents': '//root/zab/a'\n"
2390       "                }\n"
2391       "              ]\n"
2392       "},\n"
2393       "{\n"
2394       "  'type': 'directory',\n"
2395       "  'name': '//root/baz/',\n"
2396       "  'contents': [ {\n"
2397       "                  'type': 'file',\n"
2398       "                  'name': 'y',\n"
2399       "                  'external-contents': '//root/zab/b'\n"
2400       "                }\n"
2401       "              ]\n"
2402       "}\n"
2403       "]\n"
2404       "}",
2405       Lower);
2406   ASSERT_NE(FS.get(), nullptr);
2407 
2408   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
2409       new vfs::OverlayFileSystem(Lower));
2410   O->pushOverlay(FS);
2411 
2412   std::error_code EC;
2413 
2414   checkContents(O->dir_begin("//root/baz/", EC),
2415                 {"//root/baz/x", "//root/baz/y"});
2416 }
2417 
2418 TEST_F(VFSFromYAMLTest, RecursiveDirectoryIterationLevel) {
2419 
2420   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2421   Lower->addDirectory("//root/a");
2422   Lower->addDirectory("//root/a/b");
2423   Lower->addDirectory("//root/a/b/c");
2424   Lower->addRegularFile("//root/a/b/c/file");
2425   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2426       "{ 'use-external-names': false,\n"
2427       "  'roots': [\n"
2428       "{\n"
2429       "  'type': 'directory',\n"
2430       "  'name': '//root/a/b/c/',\n"
2431       "  'contents': [ {\n"
2432       "                  'type': 'file',\n"
2433       "                  'name': 'file',\n"
2434       "                  'external-contents': '//root/a/b/c/file'\n"
2435       "                }\n"
2436       "              ]\n"
2437       "},\n"
2438       "]\n"
2439       "}",
2440       Lower);
2441   ASSERT_NE(FS.get(), nullptr);
2442 
2443   IntrusiveRefCntPtr<vfs::OverlayFileSystem> O(
2444       new vfs::OverlayFileSystem(Lower));
2445   O->pushOverlay(FS);
2446 
2447   std::error_code EC;
2448 
2449   // Test recursive_directory_iterator level()
2450   vfs::recursive_directory_iterator I = vfs::recursive_directory_iterator(
2451                                         *O, "//root", EC),
2452                                     E;
2453   ASSERT_FALSE(EC);
2454   for (int l = 0; I != E; I.increment(EC), ++l) {
2455     ASSERT_FALSE(EC);
2456     EXPECT_EQ(I.level(), l);
2457   }
2458   EXPECT_EQ(I, E);
2459 }
2460 
2461 TEST_F(VFSFromYAMLTest, RelativePaths) {
2462   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2463   std::error_code EC;
2464   SmallString<128> CWD;
2465   EC = llvm::sys::fs::current_path(CWD);
2466   ASSERT_FALSE(EC);
2467 
2468   // Filename at root level without a parent directory.
2469   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2470       "{ 'roots': [\n"
2471       "  { 'type': 'file', 'name': 'file-not-in-directory.h',\n"
2472       "    'external-contents': '//root/external/file'\n"
2473       "  }\n"
2474       "] }",
2475       Lower);
2476   ASSERT_TRUE(FS.get() != nullptr);
2477   SmallString<128> ExpectedPathNotInDir("file-not-in-directory.h");
2478   llvm::sys::fs::make_absolute(ExpectedPathNotInDir);
2479   checkContents(FS->dir_begin(CWD, EC), {ExpectedPathNotInDir});
2480 
2481   // Relative file path.
2482   FS = getFromYAMLString("{ 'roots': [\n"
2483                          "  { 'type': 'file', 'name': 'relative/path.h',\n"
2484                          "    'external-contents': '//root/external/file'\n"
2485                          "  }\n"
2486                          "] }",
2487                          Lower);
2488   ASSERT_TRUE(FS.get() != nullptr);
2489   SmallString<128> Parent("relative");
2490   llvm::sys::fs::make_absolute(Parent);
2491   auto I = FS->dir_begin(Parent, EC);
2492   ASSERT_FALSE(EC);
2493   // Convert to POSIX path for comparison of windows paths
2494   ASSERT_EQ("relative/path.h",
2495             getPosixPath(std::string(I->path().substr(CWD.size() + 1))));
2496 
2497   // Relative directory path.
2498   FS = getFromYAMLString(
2499       "{ 'roots': [\n"
2500       "  { 'type': 'directory', 'name': 'relative/directory/path.h',\n"
2501       "    'contents': []\n"
2502       "  }\n"
2503       "] }",
2504       Lower);
2505   ASSERT_TRUE(FS.get() != nullptr);
2506   SmallString<128> Root("relative/directory");
2507   llvm::sys::fs::make_absolute(Root);
2508   I = FS->dir_begin(Root, EC);
2509   ASSERT_FALSE(EC);
2510   ASSERT_EQ("path.h", std::string(I->path().substr(Root.size() + 1)));
2511 
2512   EXPECT_EQ(0, NumDiagnostics);
2513 }
2514 
2515 TEST_F(VFSFromYAMLTest, NonFallthroughDirectoryIteration) {
2516   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2517   Lower->addDirectory("//root/");
2518   Lower->addRegularFile("//root/a");
2519   Lower->addRegularFile("//root/b");
2520   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2521       "{ 'use-external-names': false,\n"
2522       "  'fallthrough': false,\n"
2523       "  'roots': [\n"
2524       "{\n"
2525       "  'type': 'directory',\n"
2526       "  'name': '//root/',\n"
2527       "  'contents': [ {\n"
2528       "                  'type': 'file',\n"
2529       "                  'name': 'c',\n"
2530       "                  'external-contents': '//root/a'\n"
2531       "                }\n"
2532       "              ]\n"
2533       "}\n"
2534       "]\n"
2535       "}",
2536       Lower);
2537   ASSERT_NE(FS.get(), nullptr);
2538 
2539   std::error_code EC;
2540   checkContents(FS->dir_begin("//root/", EC),
2541                 {"//root/c"});
2542 }
2543 
2544 TEST_F(VFSFromYAMLTest, DirectoryIterationWithDuplicates) {
2545   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2546   Lower->addDirectory("//root/");
2547   Lower->addRegularFile("//root/a");
2548   Lower->addRegularFile("//root/b");
2549   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2550       "{ 'use-external-names': false,\n"
2551       "  'roots': [\n"
2552       "{\n"
2553       "  'type': 'directory',\n"
2554       "  'name': '//root/',\n"
2555       "  'contents': [ {\n"
2556       "                  'type': 'file',\n"
2557       "                  'name': 'a',\n"
2558       "                  'external-contents': '//root/a'\n"
2559       "                }\n"
2560       "              ]\n"
2561       "}\n"
2562       "]\n"
2563       "}",
2564 	  Lower);
2565   ASSERT_NE(FS.get(), nullptr);
2566 
2567   std::error_code EC;
2568   checkContents(FS->dir_begin("//root/", EC),
2569                 {"//root/a", "//root/b"});
2570 }
2571 
2572 TEST_F(VFSFromYAMLTest, DirectoryIterationErrorInVFSLayer) {
2573   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2574   Lower->addDirectory("//root/");
2575   Lower->addDirectory("//root/foo");
2576   Lower->addRegularFile("//root/foo/a");
2577   Lower->addRegularFile("//root/foo/b");
2578   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2579       "{ 'use-external-names': false,\n"
2580       "  'roots': [\n"
2581       "{\n"
2582       "  'type': 'directory',\n"
2583       "  'name': '//root/',\n"
2584       "  'contents': [ {\n"
2585       "                  'type': 'file',\n"
2586       "                  'name': 'bar/a',\n"
2587       "                  'external-contents': '//root/foo/a'\n"
2588       "                }\n"
2589       "              ]\n"
2590       "}\n"
2591       "]\n"
2592       "}",
2593       Lower);
2594   ASSERT_NE(FS.get(), nullptr);
2595 
2596   std::error_code EC;
2597   checkContents(FS->dir_begin("//root/foo", EC),
2598                 {"//root/foo/a", "//root/foo/b"});
2599 }
2600 
2601 TEST_F(VFSFromYAMLTest, GetRealPath) {
2602   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2603   Lower->addDirectory("//dir/");
2604   Lower->addRegularFile("/foo");
2605   Lower->addSymlink("/link");
2606   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2607       "{ 'use-external-names': false,\n"
2608       "  'case-sensitive': false,\n"
2609       "  'roots': [\n"
2610       "{\n"
2611       "  'type': 'directory',\n"
2612       "  'name': '//root/',\n"
2613       "  'contents': [ {\n"
2614       "                  'type': 'file',\n"
2615       "                  'name': 'bar',\n"
2616       "                  'external-contents': '/link'\n"
2617       "                },\n"
2618       "                {\n"
2619       "                  'type': 'directory',\n"
2620       "                  'name': 'baz',\n"
2621       "                  'contents': []\n"
2622       "                }\n"
2623       "              ]\n"
2624       "},\n"
2625       "{\n"
2626       "  'type': 'directory',\n"
2627       "  'name': '//dir/',\n"
2628       "  'contents': []\n"
2629       "}\n"
2630       "]\n"
2631       "}",
2632       Lower);
2633   ASSERT_NE(FS.get(), nullptr);
2634 
2635   // Regular file present in underlying file system.
2636   SmallString<16> RealPath;
2637   EXPECT_FALSE(FS->getRealPath("/foo", RealPath));
2638   EXPECT_EQ(RealPath.str(), "/foo");
2639 
2640   // File present in YAML pointing to symlink in underlying file system.
2641   EXPECT_FALSE(FS->getRealPath("//root/bar", RealPath));
2642   EXPECT_EQ(RealPath.str(), "/symlink");
2643 
2644   // Directories should return the virtual path as written in the definition.
2645   EXPECT_FALSE(FS->getRealPath("//ROOT/baz", RealPath));
2646   EXPECT_EQ(RealPath.str(), "//root/baz");
2647 
2648   // Try a non-existing file.
2649   EXPECT_EQ(FS->getRealPath("/non_existing", RealPath),
2650             errc::no_such_file_or_directory);
2651 }
2652 
2653 TEST_F(VFSFromYAMLTest, WorkingDirectory) {
2654   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2655   Lower->addDirectory("//root/");
2656   Lower->addDirectory("//root/foo");
2657   Lower->addRegularFile("//root/foo/a");
2658   Lower->addRegularFile("//root/foo/b");
2659   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2660       "{ 'use-external-names': false,\n"
2661       "  'roots': [\n"
2662       "{\n"
2663       "  'type': 'directory',\n"
2664       "  'name': '//root/bar',\n"
2665       "  'contents': [ {\n"
2666       "                  'type': 'file',\n"
2667       "                  'name': 'a',\n"
2668       "                  'external-contents': '//root/foo/a'\n"
2669       "                }\n"
2670       "              ]\n"
2671       "}\n"
2672       "]\n"
2673       "}",
2674       Lower);
2675   ASSERT_NE(FS.get(), nullptr);
2676   std::error_code EC = FS->setCurrentWorkingDirectory("//root/bar");
2677   ASSERT_FALSE(EC);
2678 
2679   llvm::ErrorOr<std::string> WorkingDir = FS->getCurrentWorkingDirectory();
2680   ASSERT_TRUE(WorkingDir);
2681   EXPECT_EQ(*WorkingDir, "//root/bar");
2682 
2683   llvm::ErrorOr<vfs::Status> Status = FS->status("./a");
2684   ASSERT_FALSE(Status.getError());
2685   EXPECT_TRUE(Status->isStatusKnown());
2686   EXPECT_FALSE(Status->isDirectory());
2687   EXPECT_TRUE(Status->isRegularFile());
2688   EXPECT_FALSE(Status->isSymlink());
2689   EXPECT_FALSE(Status->isOther());
2690   EXPECT_TRUE(Status->exists());
2691 
2692   EC = FS->setCurrentWorkingDirectory("bogus");
2693   ASSERT_TRUE(EC);
2694   WorkingDir = FS->getCurrentWorkingDirectory();
2695   ASSERT_TRUE(WorkingDir);
2696   EXPECT_EQ(*WorkingDir, "//root/bar");
2697 
2698   EC = FS->setCurrentWorkingDirectory("//root/");
2699   ASSERT_FALSE(EC);
2700   WorkingDir = FS->getCurrentWorkingDirectory();
2701   ASSERT_TRUE(WorkingDir);
2702   EXPECT_EQ(*WorkingDir, "//root/");
2703 
2704   EC = FS->setCurrentWorkingDirectory("bar");
2705   ASSERT_FALSE(EC);
2706   WorkingDir = FS->getCurrentWorkingDirectory();
2707   ASSERT_TRUE(WorkingDir);
2708   EXPECT_EQ(*WorkingDir, "//root/bar");
2709 }
2710 
2711 TEST_F(VFSFromYAMLTest, WorkingDirectoryFallthrough) {
2712   IntrusiveRefCntPtr<DummyFileSystem> Lower(new DummyFileSystem());
2713   Lower->addDirectory("//root/");
2714   Lower->addDirectory("//root/foo");
2715   Lower->addRegularFile("//root/foo/a");
2716   Lower->addRegularFile("//root/foo/b");
2717   Lower->addRegularFile("//root/c");
2718   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2719       "{ 'use-external-names': false,\n"
2720       "  'roots': [\n"
2721       "{\n"
2722       "  'type': 'directory',\n"
2723       "  'name': '//root/bar',\n"
2724       "  'contents': [ {\n"
2725       "                  'type': 'file',\n"
2726       "                  'name': 'a',\n"
2727       "                  'external-contents': '//root/foo/a'\n"
2728       "                }\n"
2729       "              ]\n"
2730       "},\n"
2731       "{\n"
2732       "  'type': 'directory',\n"
2733       "  'name': '//root/bar/baz',\n"
2734       "  'contents': [ {\n"
2735       "                  'type': 'file',\n"
2736       "                  'name': 'a',\n"
2737       "                  'external-contents': '//root/foo/a'\n"
2738       "                }\n"
2739       "              ]\n"
2740       "}\n"
2741       "]\n"
2742       "}",
2743       Lower);
2744   ASSERT_NE(FS.get(), nullptr);
2745   std::error_code EC = FS->setCurrentWorkingDirectory("//root/");
2746   ASSERT_FALSE(EC);
2747   ASSERT_NE(FS.get(), nullptr);
2748 
2749   llvm::ErrorOr<vfs::Status> Status = FS->status("bar/a");
2750   ASSERT_FALSE(Status.getError());
2751   EXPECT_TRUE(Status->exists());
2752 
2753   Status = FS->status("foo/a");
2754   ASSERT_FALSE(Status.getError());
2755   EXPECT_TRUE(Status->exists());
2756 
2757   EC = FS->setCurrentWorkingDirectory("//root/bar");
2758   ASSERT_FALSE(EC);
2759 
2760   Status = FS->status("./a");
2761   ASSERT_FALSE(Status.getError());
2762   EXPECT_TRUE(Status->exists());
2763 
2764   Status = FS->status("./b");
2765   ASSERT_TRUE(Status.getError());
2766 
2767   Status = FS->status("./c");
2768   ASSERT_TRUE(Status.getError());
2769 
2770   EC = FS->setCurrentWorkingDirectory("//root/");
2771   ASSERT_FALSE(EC);
2772 
2773   Status = FS->status("c");
2774   ASSERT_FALSE(Status.getError());
2775   EXPECT_TRUE(Status->exists());
2776 
2777   Status = FS->status("./bar/baz/a");
2778   ASSERT_FALSE(Status.getError());
2779   EXPECT_TRUE(Status->exists());
2780 
2781   EC = FS->setCurrentWorkingDirectory("//root/bar");
2782   ASSERT_FALSE(EC);
2783 
2784   Status = FS->status("./baz/a");
2785   ASSERT_FALSE(Status.getError());
2786   EXPECT_TRUE(Status->exists());
2787 
2788   Status = FS->status("../bar/baz/a");
2789   ASSERT_FALSE(Status.getError());
2790   EXPECT_TRUE(Status->exists());
2791 }
2792 
2793 TEST_F(VFSFromYAMLTest, WorkingDirectoryFallthroughInvalid) {
2794   IntrusiveRefCntPtr<ErrorDummyFileSystem> Lower(new ErrorDummyFileSystem());
2795   Lower->addDirectory("//root/");
2796   Lower->addDirectory("//root/foo");
2797   Lower->addRegularFile("//root/foo/a");
2798   Lower->addRegularFile("//root/foo/b");
2799   Lower->addRegularFile("//root/c");
2800   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2801       "{ 'use-external-names': false,\n"
2802       "  'roots': [\n"
2803       "{\n"
2804       "  'type': 'directory',\n"
2805       "  'name': '//root/bar',\n"
2806       "  'contents': [ {\n"
2807       "                  'type': 'file',\n"
2808       "                  'name': 'a',\n"
2809       "                  'external-contents': '//root/foo/a'\n"
2810       "                }\n"
2811       "              ]\n"
2812       "}\n"
2813       "]\n"
2814       "}",
2815       Lower);
2816   ASSERT_NE(FS.get(), nullptr);
2817   std::error_code EC = FS->setCurrentWorkingDirectory("//root/");
2818   ASSERT_FALSE(EC);
2819   ASSERT_NE(FS.get(), nullptr);
2820 
2821   llvm::ErrorOr<vfs::Status> Status = FS->status("bar/a");
2822   ASSERT_FALSE(Status.getError());
2823   EXPECT_TRUE(Status->exists());
2824 
2825   Status = FS->status("foo/a");
2826   ASSERT_FALSE(Status.getError());
2827   EXPECT_TRUE(Status->exists());
2828 }
2829 
2830 TEST_F(VFSFromYAMLTest, VirtualWorkingDirectory) {
2831   IntrusiveRefCntPtr<ErrorDummyFileSystem> Lower(new ErrorDummyFileSystem());
2832   Lower->addDirectory("//root/");
2833   Lower->addDirectory("//root/foo");
2834   Lower->addRegularFile("//root/foo/a");
2835   Lower->addRegularFile("//root/foo/b");
2836   Lower->addRegularFile("//root/c");
2837   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLString(
2838       "{ 'use-external-names': false,\n"
2839       "  'roots': [\n"
2840       "{\n"
2841       "  'type': 'directory',\n"
2842       "  'name': '//root/bar',\n"
2843       "  'contents': [ {\n"
2844       "                  'type': 'file',\n"
2845       "                  'name': 'a',\n"
2846       "                  'external-contents': '//root/foo/a'\n"
2847       "                }\n"
2848       "              ]\n"
2849       "}\n"
2850       "]\n"
2851       "}",
2852       Lower);
2853   ASSERT_NE(FS.get(), nullptr);
2854   std::error_code EC = FS->setCurrentWorkingDirectory("//root/bar");
2855   ASSERT_FALSE(EC);
2856   ASSERT_NE(FS.get(), nullptr);
2857 
2858   llvm::ErrorOr<vfs::Status> Status = FS->status("a");
2859   ASSERT_FALSE(Status.getError());
2860   EXPECT_TRUE(Status->exists());
2861 }
2862 
2863 TEST_F(VFSFromYAMLTest, YAMLVFSWriterTest) {
2864   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
2865   TempDir _a(TestDirectory.path("a"));
2866   TempFile _ab(TestDirectory.path("a, b"));
2867   TempDir _c(TestDirectory.path("c"));
2868   TempFile _cd(TestDirectory.path("c/d"));
2869   TempDir _e(TestDirectory.path("e"));
2870   TempDir _ef(TestDirectory.path("e/f"));
2871   TempFile _g(TestDirectory.path("g"));
2872   TempDir _h(TestDirectory.path("h"));
2873 
2874   vfs::YAMLVFSWriter VFSWriter;
2875   VFSWriter.addDirectoryMapping(_a.path(), "//root/a");
2876   VFSWriter.addFileMapping(_ab.path(), "//root/a/b");
2877   VFSWriter.addFileMapping(_cd.path(), "//root/c/d");
2878   VFSWriter.addDirectoryMapping(_e.path(), "//root/e");
2879   VFSWriter.addDirectoryMapping(_ef.path(), "//root/e/f");
2880   VFSWriter.addFileMapping(_g.path(), "//root/g");
2881   VFSWriter.addDirectoryMapping(_h.path(), "//root/h");
2882 
2883   std::string Buffer;
2884   raw_string_ostream OS(Buffer);
2885   VFSWriter.write(OS);
2886   OS.flush();
2887 
2888   IntrusiveRefCntPtr<ErrorDummyFileSystem> Lower(new ErrorDummyFileSystem());
2889   Lower->addDirectory("//root/");
2890   Lower->addDirectory("//root/a");
2891   Lower->addRegularFile("//root/a/b");
2892   Lower->addDirectory("//root/b");
2893   Lower->addDirectory("//root/c");
2894   Lower->addRegularFile("//root/c/d");
2895   Lower->addDirectory("//root/e");
2896   Lower->addDirectory("//root/e/f");
2897   Lower->addRegularFile("//root/g");
2898   Lower->addDirectory("//root/h");
2899 
2900   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLRawString(Buffer, Lower);
2901   ASSERT_NE(FS.get(), nullptr);
2902 
2903   EXPECT_TRUE(FS->exists(_a.path()));
2904   EXPECT_TRUE(FS->exists(_ab.path()));
2905   EXPECT_TRUE(FS->exists(_c.path()));
2906   EXPECT_TRUE(FS->exists(_cd.path()));
2907   EXPECT_TRUE(FS->exists(_e.path()));
2908   EXPECT_TRUE(FS->exists(_ef.path()));
2909   EXPECT_TRUE(FS->exists(_g.path()));
2910   EXPECT_TRUE(FS->exists(_h.path()));
2911 }
2912 
2913 TEST_F(VFSFromYAMLTest, YAMLVFSWriterTest2) {
2914   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
2915   TempDir _a(TestDirectory.path("a"));
2916   TempFile _ab(TestDirectory.path("a/b"));
2917   TempDir _ac(TestDirectory.path("a/c"));
2918   TempFile _acd(TestDirectory.path("a/c/d"));
2919   TempFile _ace(TestDirectory.path("a/c/e"));
2920   TempFile _acf(TestDirectory.path("a/c/f"));
2921   TempDir _ag(TestDirectory.path("a/g"));
2922   TempFile _agh(TestDirectory.path("a/g/h"));
2923 
2924   vfs::YAMLVFSWriter VFSWriter;
2925   VFSWriter.addDirectoryMapping(_a.path(), "//root/a");
2926   VFSWriter.addFileMapping(_ab.path(), "//root/a/b");
2927   VFSWriter.addDirectoryMapping(_ac.path(), "//root/a/c");
2928   VFSWriter.addFileMapping(_acd.path(), "//root/a/c/d");
2929   VFSWriter.addFileMapping(_ace.path(), "//root/a/c/e");
2930   VFSWriter.addFileMapping(_acf.path(), "//root/a/c/f");
2931   VFSWriter.addDirectoryMapping(_ag.path(), "//root/a/g");
2932   VFSWriter.addFileMapping(_agh.path(), "//root/a/g/h");
2933 
2934   std::string Buffer;
2935   raw_string_ostream OS(Buffer);
2936   VFSWriter.write(OS);
2937   OS.flush();
2938 
2939   IntrusiveRefCntPtr<ErrorDummyFileSystem> Lower(new ErrorDummyFileSystem());
2940   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLRawString(Buffer, Lower);
2941   EXPECT_NE(FS.get(), nullptr);
2942 }
2943 
2944 TEST_F(VFSFromYAMLTest, YAMLVFSWriterTest3) {
2945   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
2946   TempDir _a(TestDirectory.path("a"));
2947   TempFile _ab(TestDirectory.path("a/b"));
2948   TempDir _ac(TestDirectory.path("a/c"));
2949   TempDir _acd(TestDirectory.path("a/c/d"));
2950   TempDir _acde(TestDirectory.path("a/c/d/e"));
2951   TempFile _acdef(TestDirectory.path("a/c/d/e/f"));
2952   TempFile _acdeg(TestDirectory.path("a/c/d/e/g"));
2953   TempDir _ah(TestDirectory.path("a/h"));
2954   TempFile _ahi(TestDirectory.path("a/h/i"));
2955 
2956   vfs::YAMLVFSWriter VFSWriter;
2957   VFSWriter.addDirectoryMapping(_a.path(), "//root/a");
2958   VFSWriter.addFileMapping(_ab.path(), "//root/a/b");
2959   VFSWriter.addDirectoryMapping(_ac.path(), "//root/a/c");
2960   VFSWriter.addDirectoryMapping(_acd.path(), "//root/a/c/d");
2961   VFSWriter.addDirectoryMapping(_acde.path(), "//root/a/c/d/e");
2962   VFSWriter.addFileMapping(_acdef.path(), "//root/a/c/d/e/f");
2963   VFSWriter.addFileMapping(_acdeg.path(), "//root/a/c/d/e/g");
2964   VFSWriter.addDirectoryMapping(_ahi.path(), "//root/a/h");
2965   VFSWriter.addFileMapping(_ahi.path(), "//root/a/h/i");
2966 
2967   std::string Buffer;
2968   raw_string_ostream OS(Buffer);
2969   VFSWriter.write(OS);
2970   OS.flush();
2971 
2972   IntrusiveRefCntPtr<ErrorDummyFileSystem> Lower(new ErrorDummyFileSystem());
2973   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLRawString(Buffer, Lower);
2974   EXPECT_NE(FS.get(), nullptr);
2975 }
2976 
2977 TEST_F(VFSFromYAMLTest, YAMLVFSWriterTestHandleDirs) {
2978   TempDir TestDirectory("virtual-file-system-test", /*Unique*/ true);
2979   TempDir _a(TestDirectory.path("a"));
2980   TempDir _b(TestDirectory.path("b"));
2981   TempDir _c(TestDirectory.path("c"));
2982 
2983   vfs::YAMLVFSWriter VFSWriter;
2984   VFSWriter.addDirectoryMapping(_a.path(), "//root/a");
2985   VFSWriter.addDirectoryMapping(_b.path(), "//root/b");
2986   VFSWriter.addDirectoryMapping(_c.path(), "//root/c");
2987 
2988   std::string Buffer;
2989   raw_string_ostream OS(Buffer);
2990   VFSWriter.write(OS);
2991   OS.flush();
2992 
2993   // We didn't add a single file - only directories.
2994   EXPECT_EQ(Buffer.find("'type': 'file'"), std::string::npos);
2995 
2996   IntrusiveRefCntPtr<ErrorDummyFileSystem> Lower(new ErrorDummyFileSystem());
2997   Lower->addDirectory("//root/a");
2998   Lower->addDirectory("//root/b");
2999   Lower->addDirectory("//root/c");
3000   // canaries
3001   Lower->addRegularFile("//root/a/a");
3002   Lower->addRegularFile("//root/b/b");
3003   Lower->addRegularFile("//root/c/c");
3004 
3005   IntrusiveRefCntPtr<vfs::FileSystem> FS = getFromYAMLRawString(Buffer, Lower);
3006   ASSERT_NE(FS.get(), nullptr);
3007 
3008   EXPECT_FALSE(FS->exists(_a.path("a")));
3009   EXPECT_FALSE(FS->exists(_b.path("b")));
3010   EXPECT_FALSE(FS->exists(_c.path("c")));
3011 }
3012 
3013 TEST_F(VFSFromYAMLTest, RedirectingWith) {
3014   IntrusiveRefCntPtr<DummyFileSystem> Both(new DummyFileSystem());
3015   Both->addDirectory("//root/a");
3016   Both->addRegularFile("//root/a/f");
3017   Both->addDirectory("//root/b");
3018   Both->addRegularFile("//root/b/f");
3019 
3020   IntrusiveRefCntPtr<DummyFileSystem> AOnly(new DummyFileSystem());
3021   AOnly->addDirectory("//root/a");
3022   AOnly->addRegularFile("//root/a/f");
3023 
3024   IntrusiveRefCntPtr<DummyFileSystem> BOnly(new DummyFileSystem());
3025   BOnly->addDirectory("//root/b");
3026   BOnly->addRegularFile("//root/b/f");
3027 
3028   auto BaseStr = std::string("  'roots': [\n"
3029                              "    {\n"
3030                              "      'type': 'directory-remap',\n"
3031                              "      'name': '//root/a',\n"
3032                              "      'external-contents': '//root/b'\n"
3033                              "    }\n"
3034                              "  ]\n"
3035                              "}");
3036   auto FallthroughStr = "{ 'redirecting-with': 'fallthrough',\n" + BaseStr;
3037   auto FallbackStr = "{ 'redirecting-with': 'fallback',\n" + BaseStr;
3038   auto RedirectOnlyStr = "{ 'redirecting-with': 'redirect-only',\n" + BaseStr;
3039 
3040   auto ExpectPath = [&](vfs::FileSystem &FS, StringRef Expected,
3041                         StringRef Message) {
3042     auto AF = FS.openFileForRead("//root/a/f");
3043     ASSERT_FALSE(AF.getError()) << Message;
3044     auto AFName = (*AF)->getName();
3045     ASSERT_FALSE(AFName.getError()) << Message;
3046     EXPECT_EQ(Expected.str(), AFName.get()) << Message;
3047 
3048     auto AS = FS.status("//root/a/f");
3049     ASSERT_FALSE(AS.getError()) << Message;
3050     EXPECT_EQ(Expected.str(), AS->getName()) << Message;
3051   };
3052 
3053   auto ExpectFailure = [&](vfs::FileSystem &FS, StringRef Message) {
3054     EXPECT_TRUE(FS.openFileForRead("//root/a/f").getError()) << Message;
3055     EXPECT_TRUE(FS.status("//root/a/f").getError()) << Message;
3056   };
3057 
3058   {
3059     // `f` in both `a` and `b`
3060 
3061     // `fallthrough` tries `external-name` first, so should be `b`
3062     IntrusiveRefCntPtr<vfs::FileSystem> Fallthrough =
3063         getFromYAMLString(FallthroughStr, Both);
3064     ASSERT_TRUE(Fallthrough.get() != nullptr);
3065     ExpectPath(*Fallthrough, "//root/b/f", "fallthrough, both exist");
3066 
3067     // `fallback` tries the original name first, so should be `a`
3068     IntrusiveRefCntPtr<vfs::FileSystem> Fallback =
3069         getFromYAMLString(FallbackStr, Both);
3070     ASSERT_TRUE(Fallback.get() != nullptr);
3071     ExpectPath(*Fallback, "//root/a/f", "fallback, both exist");
3072 
3073     // `redirect-only` is the same as `fallthrough` but doesn't try the
3074     // original on failure, so no change here (ie. `b`)
3075     IntrusiveRefCntPtr<vfs::FileSystem> Redirect =
3076         getFromYAMLString(RedirectOnlyStr, Both);
3077     ASSERT_TRUE(Redirect.get() != nullptr);
3078     ExpectPath(*Redirect, "//root/b/f", "redirect-only, both exist");
3079   }
3080 
3081   {
3082     // `f` in `a` only
3083 
3084     // Fallthrough to the original path, `a`
3085     IntrusiveRefCntPtr<vfs::FileSystem> Fallthrough =
3086         getFromYAMLString(FallthroughStr, AOnly);
3087     ASSERT_TRUE(Fallthrough.get() != nullptr);
3088     ExpectPath(*Fallthrough, "//root/a/f", "fallthrough, a only");
3089 
3090     // Original first, so still `a`
3091     IntrusiveRefCntPtr<vfs::FileSystem> Fallback =
3092         getFromYAMLString(FallbackStr, AOnly);
3093     ASSERT_TRUE(Fallback.get() != nullptr);
3094     ExpectPath(*Fallback, "//root/a/f", "fallback, a only");
3095 
3096     // Fails since no fallthrough
3097     IntrusiveRefCntPtr<vfs::FileSystem> Redirect =
3098         getFromYAMLString(RedirectOnlyStr, AOnly);
3099     ASSERT_TRUE(Redirect.get() != nullptr);
3100     ExpectFailure(*Redirect, "redirect-only, a only");
3101   }
3102 
3103   {
3104     // `f` in `b` only
3105 
3106     // Tries `b` first (no fallthrough)
3107     IntrusiveRefCntPtr<vfs::FileSystem> Fallthrough =
3108         getFromYAMLString(FallthroughStr, BOnly);
3109     ASSERT_TRUE(Fallthrough.get() != nullptr);
3110     ExpectPath(*Fallthrough, "//root/b/f", "fallthrough, b only");
3111 
3112     // Tries original first but then fallsback to `b`
3113     IntrusiveRefCntPtr<vfs::FileSystem> Fallback =
3114         getFromYAMLString(FallbackStr, BOnly);
3115     ASSERT_TRUE(Fallback.get() != nullptr);
3116     ExpectPath(*Fallback, "//root/b/f", "fallback, b only");
3117 
3118     // Redirect exists, so uses it (`b`)
3119     IntrusiveRefCntPtr<vfs::FileSystem> Redirect =
3120         getFromYAMLString(RedirectOnlyStr, BOnly);
3121     ASSERT_TRUE(Redirect.get() != nullptr);
3122     ExpectPath(*Redirect, "//root/b/f", "redirect-only, b only");
3123   }
3124 
3125   EXPECT_EQ(0, NumDiagnostics);
3126 }
3127 
3128 TEST(VFSFromRemappedFilesTest, Basic) {
3129   IntrusiveRefCntPtr<vfs::InMemoryFileSystem> BaseFS =
3130       new vfs::InMemoryFileSystem;
3131   BaseFS->addFile("//root/b", 0, MemoryBuffer::getMemBuffer("contents of b"));
3132   BaseFS->addFile("//root/c", 0, MemoryBuffer::getMemBuffer("contents of c"));
3133 
3134   std::vector<std::pair<std::string, std::string>> RemappedFiles = {
3135       {"//root/a/a", "//root/b"},
3136       {"//root/a/b/c", "//root/c"},
3137   };
3138   auto RemappedFS = vfs::RedirectingFileSystem::create(
3139       RemappedFiles, /*UseExternalNames=*/false, *BaseFS);
3140 
3141   auto StatA = RemappedFS->status("//root/a/a");
3142   auto StatB = RemappedFS->status("//root/a/b/c");
3143   ASSERT_TRUE(StatA);
3144   ASSERT_TRUE(StatB);
3145   EXPECT_EQ("//root/a/a", StatA->getName());
3146   EXPECT_EQ("//root/a/b/c", StatB->getName());
3147 
3148   auto BufferA = RemappedFS->getBufferForFile("//root/a/a");
3149   auto BufferB = RemappedFS->getBufferForFile("//root/a/b/c");
3150   ASSERT_TRUE(BufferA);
3151   ASSERT_TRUE(BufferB);
3152   EXPECT_EQ("contents of b", (*BufferA)->getBuffer());
3153   EXPECT_EQ("contents of c", (*BufferB)->getBuffer());
3154 }
3155 
3156 TEST(VFSFromRemappedFilesTest, UseExternalNames) {
3157   IntrusiveRefCntPtr<vfs::InMemoryFileSystem> BaseFS =
3158       new vfs::InMemoryFileSystem;
3159   BaseFS->addFile("//root/b", 0, MemoryBuffer::getMemBuffer("contents of b"));
3160   BaseFS->addFile("//root/c", 0, MemoryBuffer::getMemBuffer("contents of c"));
3161 
3162   std::vector<std::pair<std::string, std::string>> RemappedFiles = {
3163       {"//root/a/a", "//root/b"},
3164       {"//root/a/b/c", "//root/c"},
3165   };
3166   auto RemappedFS = vfs::RedirectingFileSystem::create(
3167       RemappedFiles, /*UseExternalNames=*/true, *BaseFS);
3168 
3169   auto StatA = RemappedFS->status("//root/a/a");
3170   auto StatB = RemappedFS->status("//root/a/b/c");
3171   ASSERT_TRUE(StatA);
3172   ASSERT_TRUE(StatB);
3173   EXPECT_EQ("//root/b", StatA->getName());
3174   EXPECT_EQ("//root/c", StatB->getName());
3175 
3176   auto BufferA = RemappedFS->getBufferForFile("//root/a/a");
3177   auto BufferB = RemappedFS->getBufferForFile("//root/a/b/c");
3178   ASSERT_TRUE(BufferA);
3179   ASSERT_TRUE(BufferB);
3180   EXPECT_EQ("contents of b", (*BufferA)->getBuffer());
3181   EXPECT_EQ("contents of c", (*BufferB)->getBuffer());
3182 }
3183 
3184 TEST(VFSFromRemappedFilesTest, LastMappingWins) {
3185   IntrusiveRefCntPtr<vfs::InMemoryFileSystem> BaseFS =
3186       new vfs::InMemoryFileSystem;
3187   BaseFS->addFile("//root/b", 0, MemoryBuffer::getMemBuffer("contents of b"));
3188   BaseFS->addFile("//root/c", 0, MemoryBuffer::getMemBuffer("contents of c"));
3189 
3190   std::vector<std::pair<std::string, std::string>> RemappedFiles = {
3191       {"//root/a", "//root/b"},
3192       {"//root/a", "//root/c"},
3193   };
3194   auto RemappedFSKeepName = vfs::RedirectingFileSystem::create(
3195       RemappedFiles, /*UseExternalNames=*/false, *BaseFS);
3196   auto RemappedFSExternalName = vfs::RedirectingFileSystem::create(
3197       RemappedFiles, /*UseExternalNames=*/true, *BaseFS);
3198 
3199   auto StatKeepA = RemappedFSKeepName->status("//root/a");
3200   auto StatExternalA = RemappedFSExternalName->status("//root/a");
3201   ASSERT_TRUE(StatKeepA);
3202   ASSERT_TRUE(StatExternalA);
3203   EXPECT_EQ("//root/a", StatKeepA->getName());
3204   EXPECT_EQ("//root/c", StatExternalA->getName());
3205 
3206   auto BufferKeepA = RemappedFSKeepName->getBufferForFile("//root/a");
3207   auto BufferExternalA = RemappedFSExternalName->getBufferForFile("//root/a");
3208   ASSERT_TRUE(BufferKeepA);
3209   ASSERT_TRUE(BufferExternalA);
3210   EXPECT_EQ("contents of c", (*BufferKeepA)->getBuffer());
3211   EXPECT_EQ("contents of c", (*BufferExternalA)->getBuffer());
3212 }
3213 
3214 TEST(RedirectingFileSystemTest, PrintOutput) {
3215   auto Buffer =
3216       MemoryBuffer::getMemBuffer("{\n"
3217                                  "  'version': 0,\n"
3218                                  "  'roots': [\n"
3219                                  "    {\n"
3220                                  "      'type': 'directory-remap',\n"
3221                                  "      'name': '/dremap',\n"
3222                                  "      'external-contents': '/a',\n"
3223                                  "    },"
3224                                  "    {\n"
3225                                  "      'type': 'directory',\n"
3226                                  "      'name': '/vdir',\n"
3227                                  "      'contents': ["
3228                                  "        {\n"
3229                                  "          'type': 'directory-remap',\n"
3230                                  "          'name': 'dremap',\n"
3231                                  "          'external-contents': '/b'\n"
3232                                  "          'use-external-name': 'true'\n"
3233                                  "        },\n"
3234                                  "        {\n"
3235                                  "          'type': 'file',\n"
3236                                  "          'name': 'vfile',\n"
3237                                  "          'external-contents': '/c'\n"
3238                                  "          'use-external-name': 'false'\n"
3239                                  "        }]\n"
3240                                  "    }]\n"
3241                                  "}");
3242 
3243   auto Dummy = makeIntrusiveRefCnt<DummyFileSystem>();
3244   auto Redirecting = vfs::RedirectingFileSystem::create(
3245       std::move(Buffer), nullptr, "", nullptr, Dummy);
3246 
3247   SmallString<0> Output;
3248   raw_svector_ostream OuputStream{Output};
3249 
3250   Redirecting->print(OuputStream, vfs::FileSystem::PrintType::Summary);
3251   ASSERT_EQ("RedirectingFileSystem (UseExternalNames: true)\n", Output);
3252 
3253   Output.clear();
3254   Redirecting->print(OuputStream, vfs::FileSystem::PrintType::Contents);
3255   ASSERT_EQ("RedirectingFileSystem (UseExternalNames: true)\n"
3256             "'/'\n"
3257             "  'dremap' -> '/a'\n"
3258             "  'vdir'\n"
3259             "    'dremap' -> '/b' (UseExternalName: true)\n"
3260             "    'vfile' -> '/c' (UseExternalName: false)\n"
3261             "ExternalFS:\n"
3262             "  DummyFileSystem (Summary)\n",
3263             Output);
3264 
3265   Output.clear();
3266   Redirecting->print(OuputStream, vfs::FileSystem::PrintType::Contents, 1);
3267   ASSERT_EQ("  RedirectingFileSystem (UseExternalNames: true)\n"
3268             "  '/'\n"
3269             "    'dremap' -> '/a'\n"
3270             "    'vdir'\n"
3271             "      'dremap' -> '/b' (UseExternalName: true)\n"
3272             "      'vfile' -> '/c' (UseExternalName: false)\n"
3273             "  ExternalFS:\n"
3274             "    DummyFileSystem (Summary)\n",
3275             Output);
3276 
3277   Output.clear();
3278   Redirecting->print(OuputStream,
3279                      vfs::FileSystem::PrintType::RecursiveContents);
3280   ASSERT_EQ("RedirectingFileSystem (UseExternalNames: true)\n"
3281             "'/'\n"
3282             "  'dremap' -> '/a'\n"
3283             "  'vdir'\n"
3284             "    'dremap' -> '/b' (UseExternalName: true)\n"
3285             "    'vfile' -> '/c' (UseExternalName: false)\n"
3286             "ExternalFS:\n"
3287             "  DummyFileSystem (RecursiveContents)\n",
3288             Output);
3289 }
3290 
3291 TEST(RedirectingFileSystemTest, Used) {
3292   auto Dummy = makeIntrusiveRefCnt<DummyFileSystem>();
3293   auto YAML1 =
3294       MemoryBuffer::getMemBuffer("{\n"
3295                                  "  'version': 0,\n"
3296                                  "  'redirecting-with': 'fallthrough',\n"
3297                                  "  'roots': [\n"
3298                                  "    {\n"
3299                                  "      'type': 'file',\n"
3300                                  "      'name': '/vfile1',\n"
3301                                  "      'external-contents': '/a',\n"
3302                                  "    },"
3303                                  "  ]\n"
3304                                  "}");
3305   auto YAML2 =
3306       MemoryBuffer::getMemBuffer("{\n"
3307                                  "  'version': 0,\n"
3308                                  "  'redirecting-with': 'fallthrough',\n"
3309                                  "  'roots': [\n"
3310                                  "    {\n"
3311                                  "      'type': 'file',\n"
3312                                  "      'name': '/vfile2',\n"
3313                                  "      'external-contents': '/b',\n"
3314                                  "    },"
3315                                  "  ]\n"
3316                                  "}");
3317 
3318   Dummy->addRegularFile("/a");
3319   Dummy->addRegularFile("/b");
3320 
3321   IntrusiveRefCntPtr<vfs::RedirectingFileSystem> Redirecting1 =
3322       vfs::RedirectingFileSystem::create(std::move(YAML1), nullptr, "", nullptr,
3323                                          Dummy)
3324           .release();
3325   auto Redirecting2 = vfs::RedirectingFileSystem::create(
3326       std::move(YAML2), nullptr, "", nullptr, Redirecting1);
3327 
3328   Redirecting1->setUsageTrackingActive(true);
3329   Redirecting2->setUsageTrackingActive(true);
3330   EXPECT_TRUE(Redirecting2->exists("/vfile1"));
3331   EXPECT_TRUE(Redirecting2->exists("/b"));
3332   EXPECT_TRUE(Redirecting1->hasBeenUsed());
3333   EXPECT_FALSE(Redirecting2->hasBeenUsed());
3334 }
3335 
3336 // Check that paths looked up in the external filesystem are unmodified, except
3337 // potentially to add the working directory. We cannot canonicalize away ..
3338 // in the presence of symlinks in the external filesystem.
3339 TEST(RedirectingFileSystemTest, ExternalPaths) {
3340   struct InterceptorFS : llvm::vfs::ProxyFileSystem {
3341     std::vector<std::string> SeenPaths;
3342 
3343     InterceptorFS(IntrusiveRefCntPtr<FileSystem> UnderlyingFS)
3344         : ProxyFileSystem(UnderlyingFS) {}
3345 
3346     llvm::ErrorOr<llvm::vfs::Status> status(const Twine &Path) override {
3347       SeenPaths.push_back(Path.str());
3348       return ProxyFileSystem::status(Path);
3349     }
3350 
3351     llvm::ErrorOr<std::unique_ptr<llvm::vfs::File>>
3352     openFileForRead(const Twine &Path) override {
3353       SeenPaths.push_back(Path.str());
3354       return ProxyFileSystem::openFileForRead(Path);
3355     }
3356 
3357     std::error_code isLocal(const Twine &Path, bool &Result) override {
3358       SeenPaths.push_back(Path.str());
3359       return ProxyFileSystem::isLocal(Path, Result);
3360     }
3361 
3362     vfs::directory_iterator dir_begin(const Twine &Dir,
3363                                       std::error_code &EC) override {
3364       SeenPaths.push_back(Dir.str());
3365       return ProxyFileSystem::dir_begin(Dir, EC);
3366     }
3367   };
3368 
3369   std::error_code EC;
3370   auto BaseFS = makeIntrusiveRefCnt<DummyFileSystem>();
3371   BaseFS->setCurrentWorkingDirectory("/cwd");
3372   auto CheckFS = makeIntrusiveRefCnt<InterceptorFS>(BaseFS);
3373   auto FS = vfs::RedirectingFileSystem::create({}, /*UseExternalNames=*/false,
3374                                                *CheckFS);
3375 
3376   FS->status("/a/../b");
3377   FS->openFileForRead("c");
3378   FS->exists("./d");
3379   bool IsLocal = false;
3380   FS->isLocal("/e/./../f", IsLocal);
3381   FS->dir_begin(".././g", EC);
3382 
3383   std::vector<std::string> Expected{"/a/../b", "/cwd/c", "/cwd/./d",
3384                                     "/e/./../f", "/cwd/.././g"};
3385 
3386   EXPECT_EQ(CheckFS->SeenPaths, Expected);
3387 
3388   CheckFS->SeenPaths.clear();
3389   FS->setRedirection(vfs::RedirectingFileSystem::RedirectKind::Fallback);
3390   FS->status("/a/../b");
3391   FS->openFileForRead("c");
3392   FS->exists("./d");
3393   FS->isLocal("/e/./../f", IsLocal);
3394   FS->dir_begin(".././g", EC);
3395 
3396   EXPECT_EQ(CheckFS->SeenPaths, Expected);
3397 }
3398