1 //===- unittests/AST/ASTPrint.h ------------------------------------------===//
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 // Helpers to simplify testing of printing of AST constructs provided in the/
10 // form of the source code.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "clang/AST/ASTContext.h"
15 #include "clang/ASTMatchers/ASTMatchFinder.h"
16 #include "clang/Tooling/Tooling.h"
17 #include "llvm/ADT/SmallString.h"
18 #include "gtest/gtest.h"
19
20 namespace clang {
21
22 using PrintingPolicyAdjuster = llvm::function_ref<void(PrintingPolicy &Policy)>;
23
24 template <typename NodeType>
25 using NodePrinter =
26 std::function<void(llvm::raw_ostream &Out, const ASTContext *Context,
27 const NodeType *Node,
28 PrintingPolicyAdjuster PolicyAdjuster)>;
29
30 template <typename NodeType>
31 using NodeFilter = std::function<bool(const NodeType *Node)>;
32
33 template <typename NodeType>
34 class PrintMatch : public ast_matchers::MatchFinder::MatchCallback {
35 using PrinterT = NodePrinter<NodeType>;
36 using FilterT = NodeFilter<NodeType>;
37
38 SmallString<1024> Printed;
39 unsigned NumFoundNodes;
40 PrinterT Printer;
41 FilterT Filter;
42 PrintingPolicyAdjuster PolicyAdjuster;
43
44 public:
PrintMatch(PrinterT Printer,PrintingPolicyAdjuster PolicyAdjuster,FilterT Filter)45 PrintMatch(PrinterT Printer, PrintingPolicyAdjuster PolicyAdjuster,
46 FilterT Filter)
47 : NumFoundNodes(0), Printer(std::move(Printer)),
48 Filter(std::move(Filter)), PolicyAdjuster(PolicyAdjuster) {}
49
run(const ast_matchers::MatchFinder::MatchResult & Result)50 void run(const ast_matchers::MatchFinder::MatchResult &Result) override {
51 const NodeType *N = Result.Nodes.getNodeAs<NodeType>("id");
52 if (!N || !Filter(N))
53 return;
54 NumFoundNodes++;
55 if (NumFoundNodes > 1)
56 return;
57
58 llvm::raw_svector_ostream Out(Printed);
59 Printer(Out, Result.Context, N, PolicyAdjuster);
60 }
61
getPrinted()62 StringRef getPrinted() const { return Printed; }
63
getNumFoundNodes()64 unsigned getNumFoundNodes() const { return NumFoundNodes; }
65 };
66
NoNodeFilter(const NodeType *)67 template <typename NodeType> bool NoNodeFilter(const NodeType *) {
68 return true;
69 }
70
71 template <typename NodeType, typename Matcher>
72 ::testing::AssertionResult
73 PrintedNodeMatches(StringRef Code, const std::vector<std::string> &Args,
74 const Matcher &NodeMatch, StringRef ExpectedPrinted,
75 StringRef FileName, NodePrinter<NodeType> Printer,
76 PrintingPolicyAdjuster PolicyAdjuster = nullptr,
77 bool AllowError = false,
78 // Would like to use a lambda for the default value, but that
79 // trips gcc 7 up.
80 NodeFilter<NodeType> Filter = &NoNodeFilter<NodeType>) {
81
82 PrintMatch<NodeType> Callback(Printer, PolicyAdjuster, Filter);
83 ast_matchers::MatchFinder Finder;
84 Finder.addMatcher(NodeMatch, &Callback);
85 std::unique_ptr<tooling::FrontendActionFactory> Factory(
86 tooling::newFrontendActionFactory(&Finder));
87
88 bool ToolResult;
89 if (FileName.empty()) {
90 ToolResult = tooling::runToolOnCodeWithArgs(Factory->create(), Code, Args);
91 } else {
92 ToolResult =
93 tooling::runToolOnCodeWithArgs(Factory->create(), Code, Args, FileName);
94 }
95 if (!ToolResult && !AllowError)
96 return testing::AssertionFailure()
97 << "Parsing error in \"" << Code.str() << "\"";
98
99 if (Callback.getNumFoundNodes() == 0)
100 return testing::AssertionFailure() << "Matcher didn't find any nodes";
101
102 if (Callback.getNumFoundNodes() > 1)
103 return testing::AssertionFailure()
104 << "Matcher should match only one node (found "
105 << Callback.getNumFoundNodes() << ")";
106
107 if (Callback.getPrinted() != ExpectedPrinted)
108 return ::testing::AssertionFailure()
109 << "Expected \"" << ExpectedPrinted.str() << "\", got \""
110 << Callback.getPrinted().str() << "\"";
111
112 return ::testing::AssertionSuccess();
113 }
114
115 } // namespace clang
116