xref: /llvm-project/clang/lib/Format/TokenAnalyzer.cpp (revision 32e65b0b8a743678974c7ca7913c1d6c41bb0772)
1 //===--- TokenAnalyzer.cpp - Analyze Token Streams --------------*- C++ -*-===//
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 /// \file
10 /// This file implements an abstract TokenAnalyzer and associated helper
11 /// classes. TokenAnalyzer can be extended to generate replacements based on
12 /// an annotated and pre-processed token stream.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #include "TokenAnalyzer.h"
17 #include "AffectedRangeManager.h"
18 #include "Encoding.h"
19 #include "FormatToken.h"
20 #include "FormatTokenLexer.h"
21 #include "TokenAnnotator.h"
22 #include "UnwrappedLineParser.h"
23 #include "clang/Basic/Diagnostic.h"
24 #include "clang/Basic/DiagnosticOptions.h"
25 #include "clang/Basic/FileManager.h"
26 #include "clang/Basic/SourceManager.h"
27 #include "clang/Format/Format.h"
28 #include "llvm/ADT/STLExtras.h"
29 #include "llvm/ADT/SmallVector.h"
30 #include "llvm/Support/Debug.h"
31 #include <type_traits>
32 
33 #define DEBUG_TYPE "format-formatter"
34 
35 namespace clang {
36 namespace format {
37 
38 LangOptions LangOpts;
39 
40 // FIXME: Instead of printing the diagnostic we should store it and have a
41 // better way to return errors through the format APIs.
42 class FatalDiagnosticConsumer : public DiagnosticConsumer {
43 public:
44   void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
45                         const Diagnostic &Info) override {
46     if (DiagLevel == DiagnosticsEngine::Fatal) {
47       Fatal = true;
48       llvm::SmallVector<char, 128> Message;
49       Info.FormatDiagnostic(Message);
50       llvm::errs() << Message << "\n";
51     }
52   }
53 
54   bool fatalError() const { return Fatal; }
55 
56 private:
57   bool Fatal = false;
58 };
59 
60 std::unique_ptr<Environment>
61 Environment::make(StringRef Code, StringRef FileName,
62                   ArrayRef<tooling::Range> Ranges, unsigned FirstStartColumn,
63                   unsigned NextStartColumn, unsigned LastStartColumn) {
64   auto Env = std::make_unique<Environment>(Code, FileName, FirstStartColumn,
65                                            NextStartColumn, LastStartColumn);
66   FatalDiagnosticConsumer Diags;
67   Env->SM.getDiagnostics().setClient(&Diags, /*ShouldOwnClient=*/false);
68   SourceLocation StartOfFile = Env->SM.getLocForStartOfFile(Env->ID);
69   for (const tooling::Range &Range : Ranges) {
70     SourceLocation Start = StartOfFile.getLocWithOffset(Range.getOffset());
71     SourceLocation End = Start.getLocWithOffset(Range.getLength());
72     Env->CharRanges.push_back(CharSourceRange::getCharRange(Start, End));
73   }
74   // Validate that we can get the buffer data without a fatal error.
75   Env->SM.getBufferData(Env->ID);
76   if (Diags.fatalError())
77     return nullptr;
78   return Env;
79 }
80 
81 Environment::Environment(StringRef Code, StringRef FileName,
82                          unsigned FirstStartColumn, unsigned NextStartColumn,
83                          unsigned LastStartColumn)
84     : VirtualSM(new SourceManagerForFile(FileName, Code)), SM(VirtualSM->get()),
85       ID(VirtualSM->get().getMainFileID()), FirstStartColumn(FirstStartColumn),
86       NextStartColumn(NextStartColumn), LastStartColumn(LastStartColumn) {}
87 
88 TokenAnalyzer::TokenAnalyzer(const Environment &Env, const FormatStyle &Style)
89     : Style(Style), Env(Env),
90       AffectedRangeMgr(Env.getSourceManager(), Env.getCharRanges()),
91       UnwrappedLines(1),
92       Encoding(encoding::detectEncoding(
93           Env.getSourceManager().getBufferData(Env.getFileID()))) {
94   LLVM_DEBUG(
95       llvm::dbgs() << "File encoding: "
96                    << (Encoding == encoding::Encoding_UTF8 ? "UTF8" : "unknown")
97                    << "\n");
98   LLVM_DEBUG(llvm::dbgs() << "Language: " << getLanguageName(Style.Language)
99                           << "\n");
100 }
101 
102 std::pair<tooling::Replacements, unsigned>
103 TokenAnalyzer::process(bool SkipAnnotation) {
104   LangOpts = getFormattingLangOpts(Style);
105 
106   tooling::Replacements Result;
107   llvm::SpecificBumpPtrAllocator<FormatToken> Allocator;
108   IdentifierTable IdentTable(LangOpts);
109   FormatTokenLexer Lex(Env.getSourceManager(), Env.getFileID(),
110                        Env.getFirstStartColumn(), Style, Encoding, Allocator,
111                        IdentTable);
112   ArrayRef<FormatToken *> Toks(Lex.lex());
113   SmallVector<FormatToken *, 10> Tokens(Toks.begin(), Toks.end());
114   UnwrappedLineParser Parser(Env.getSourceManager(), Style, Lex.getKeywords(),
115                              Env.getFirstStartColumn(), Tokens, *this,
116                              Allocator, IdentTable);
117   Parser.parse();
118   assert(UnwrappedLines.back().empty());
119   unsigned Penalty = 0;
120   for (unsigned Run = 0, RunE = UnwrappedLines.size(); Run + 1 != RunE; ++Run) {
121     const auto &Lines = UnwrappedLines[Run];
122     LLVM_DEBUG(llvm::dbgs() << "Run " << Run << "...\n");
123     SmallVector<AnnotatedLine *, 16> AnnotatedLines;
124     AnnotatedLines.reserve(Lines.size());
125 
126     TokenAnnotator Annotator(Style, Lex.getKeywords());
127     for (const UnwrappedLine &Line : Lines) {
128       AnnotatedLines.push_back(new AnnotatedLine(Line));
129       if (!SkipAnnotation)
130         Annotator.annotate(*AnnotatedLines.back());
131     }
132 
133     std::pair<tooling::Replacements, unsigned> RunResult =
134         analyze(Annotator, AnnotatedLines, Lex);
135 
136     LLVM_DEBUG({
137       llvm::dbgs() << "Replacements for run " << Run << ":\n";
138       for (const tooling::Replacement &Fix : RunResult.first)
139         llvm::dbgs() << Fix.toString() << "\n";
140     });
141     for (AnnotatedLine *Line : AnnotatedLines)
142       delete Line;
143 
144     Penalty += RunResult.second;
145     for (const auto &R : RunResult.first) {
146       auto Err = Result.add(R);
147       // FIXME: better error handling here. For now, simply return an empty
148       // Replacements to indicate failure.
149       if (Err) {
150         llvm::errs() << llvm::toString(std::move(Err)) << "\n";
151         return {tooling::Replacements(), 0};
152       }
153     }
154   }
155   return {Result, Penalty};
156 }
157 
158 void TokenAnalyzer::consumeUnwrappedLine(const UnwrappedLine &TheLine) {
159   assert(!UnwrappedLines.empty());
160   UnwrappedLines.back().push_back(TheLine);
161 }
162 
163 void TokenAnalyzer::finishRun() {
164   UnwrappedLines.push_back(SmallVector<UnwrappedLine, 16>());
165 }
166 
167 } // end namespace format
168 } // end namespace clang
169