clang-tools 10.0.0

clangd/unittests/Matchers.h
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1 //===-- Matchers.h ----------------------------------------------*- 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 // GMock matchers that aren't specific to particular tests.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #ifndef LLVM_CLANG_TOOLS_EXTRA_UNITTESTS_CLANGD_MATCHERS_H
14 #define LLVM_CLANG_TOOLS_EXTRA_UNITTESTS_CLANGD_MATCHERS_H
15 #include "Protocol.h"
16 #include "gmock/gmock.h"
17
18 namespace clang {
19 namespace clangd {
20 using ::testing::Matcher;
21
22 // EXPECT_IFF expects matcher if condition is true, and Not(matcher) if false.
23 // This is hard to write as a function, because matchers may be polymorphic.
24 #define EXPECT_IFF(condition, value, matcher) \
25 do { \
26 if (condition) \
27 EXPECT_THAT(value, matcher); \
28 else \
29 EXPECT_THAT(value, ::testing::Not(matcher)); \
30 } while (0)
31
32 // HasSubsequence(m1, m2, ...) matches a vector containing elements that match
33 // m1, m2 ... in that order.
34 //
35 // SubsequenceMatcher implements this once the type of vector is known.
36 template <typename T>
37 class SubsequenceMatcher
38 : public ::testing::MatcherInterface<const std::vector<T> &> {
39 std::vector<Matcher<T>> Matchers;
40
41 public:
42 SubsequenceMatcher(std::vector<Matcher<T>> M) : Matchers(M) {}
43
44 void DescribeTo(std::ostream *OS) const override {
45 *OS << "Contains the subsequence [";
46 const char *Sep = "";
47 for (const auto &M : Matchers) {
48 *OS << Sep;
49 M.DescribeTo(OS);
50 Sep = ", ";
51 }
52 *OS << "]";
53 }
54
55 bool MatchAndExplain(const std::vector<T> &V,
56 ::testing::MatchResultListener *L) const override {
57 std::vector<int> Matches(Matchers.size());
58 size_t I = 0;
59 for (size_t J = 0; I < Matchers.size() && J < V.size(); ++J)
60 if (Matchers[I].Matches(V[J]))
61 Matches[I++] = J;
62 if (I == Matchers.size()) // We exhausted all matchers.
63 return true;
64 if (L->IsInterested()) {
65 *L << "\n Matched:";
66 for (size_t K = 0; K < I; ++K) {
67 *L << "\n\t";
68 Matchers[K].DescribeTo(L->stream());
69 *L << " ==> " << ::testing::PrintToString(V[Matches[K]]);
70 }
71 *L << "\n\t";
72 Matchers[I].DescribeTo(L->stream());
73 *L << " ==> no subsequent match";
74 }
75 return false;
76 }
77 };
78
79 // PolySubsequenceMatcher implements a "polymorphic" SubsequenceMatcher.
80 // It captures the types of the element matchers, and can be converted to
81 // Matcher<vector<T>> if each matcher can be converted to Matcher<T>.
82 // This allows HasSubsequence() to accept polymorphic matchers like Not().
83 template <typename... M> class PolySubsequenceMatcher {
84 std::tuple<M...> Matchers;
85
86 public:
87 PolySubsequenceMatcher(M &&... Args)
88 : Matchers(std::make_tuple(std::forward<M>(Args)...)) {}
89
90 template <typename T> operator Matcher<const std::vector<T> &>() const {
91 return ::testing::MakeMatcher(new SubsequenceMatcher<T>(
92 TypedMatchers<T>(std::index_sequence_for<M...>{})));
93 }
94
95 private:
96 template <typename T, size_t... I>
97 std::vector<Matcher<T>> TypedMatchers(std::index_sequence<I...>) const {
98 return {std::get<I>(Matchers)...};
99 }
100 };
101
102 // HasSubsequence(m1, m2, ...) matches a vector containing elements that match
103 // m1, m2 ... in that order.
104 // The real implementation is in SubsequenceMatcher.
105 template <typename... Args>
106 PolySubsequenceMatcher<Args...> HasSubsequence(Args &&... M) {
107 return PolySubsequenceMatcher<Args...>(std::forward<Args>(M)...);
108 }
109
110 // EXPECT_ERROR seems like a pretty generic name, make sure it's not defined
111 // already.
112 #ifdef EXPECT_ERROR
113 #error "Refusing to redefine EXPECT_ERROR"
114 #endif
115
116 // Consumes llvm::Expected<T>, checks it contains an error and marks it as
117 // handled.
118 #define EXPECT_ERROR(expectedValue) \
119 do { \
120 auto &&ComputedValue = (expectedValue); \
121 if (ComputedValue) { \
122 ADD_FAILURE() << "expected an error from " << #expectedValue \
123 << " but got " \
124 << ::testing::PrintToString(*ComputedValue); \
125 break; \
126 } \
127 llvm::consumeError(ComputedValue.takeError()); \
128 } while (false)
129
130 // Implements the HasValue(m) matcher for matching an Optional whose
131 // value matches matcher m.
132 template <typename InnerMatcher> class OptionalMatcher {
133 public:
134 explicit OptionalMatcher(const InnerMatcher &matcher) : matcher_(matcher) {}
135
136 // This type conversion operator template allows Optional(m) to be
137 // used as a matcher for any Optional type whose value type is
138 // compatible with the inner matcher.
139 //
140 // The reason we do this instead of relying on
141 // MakePolymorphicMatcher() is that the latter is not flexible
142 // enough for implementing the DescribeTo() method of Optional().
143 template <typename Optional> operator Matcher<Optional>() const {
144 return MakeMatcher(new Impl<Optional>(matcher_));
145 }
146
147 private:
148 // The monomorphic implementation that works for a particular optional type.
149 template <typename Optional>
150 class Impl : public ::testing::MatcherInterface<Optional> {
151 public:
152 using Value = typename std::remove_const<
153 typename std::remove_reference<Optional>::type>::type::value_type;
154
155 explicit Impl(const InnerMatcher &matcher)
156 : matcher_(::testing::MatcherCast<const Value &>(matcher)) {}
157
158 virtual void DescribeTo(::std::ostream *os) const {
159 *os << "has a value that ";
160 matcher_.DescribeTo(os);
161 }
162
163 virtual void DescribeNegationTo(::std::ostream *os) const {
164 *os << "does not have a value that ";
165 matcher_.DescribeTo(os);
166 }
167
168 virtual bool
169 MatchAndExplain(Optional optional,
170 ::testing::MatchResultListener *listener) const {
171 if (!optional.hasValue())
172 return false;
173
174 *listener << "which has a value ";
175 return MatchPrintAndExplain(*optional, matcher_, listener);
176 }
177
178 private:
179 const Matcher<const Value &> matcher_;
180
181 GTEST_DISALLOW_ASSIGN_(Impl);
182 };
183
184 const InnerMatcher matcher_;
185
186 GTEST_DISALLOW_ASSIGN_(OptionalMatcher);
187 };
188
189 // Creates a matcher that matches an Optional that has a value
190 // that matches inner_matcher.
191 template <typename InnerMatcher>
192 inline OptionalMatcher<InnerMatcher>
193 HasValue(const InnerMatcher &inner_matcher) {
194 return OptionalMatcher<InnerMatcher>(inner_matcher);
195 }
196
197 } // namespace clangd
198 } // namespace clang
199 #endif
clang::clangd::SubsequenceMatcher::DescribeTo
void DescribeTo(std::ostream *OS) const override
Definition: clangd/unittests/Matchers.h:44
clang::clangd::HasValue
OptionalMatcher< InnerMatcher > HasValue(const InnerMatcher &inner_matcher)
Definition: clangd/unittests/Matchers.h:193
clang::clangd::SubsequenceMatcher::MatchAndExplain
bool MatchAndExplain(const std::vector< T > &V, ::testing::MatchResultListener *L) const override
Definition: clangd/unittests/Matchers.h:55
clang::clangd::HasSubsequence
PolySubsequenceMatcher< Args... > HasSubsequence(Args &&... M)
Definition: clangd/unittests/Matchers.h:106
Protocol.h
clang::clangd::SubsequenceMatcher::SubsequenceMatcher
SubsequenceMatcher(std::vector< Matcher< T >> M)
Definition: clangd/unittests/Matchers.h:42
clang::clangd::OptionalMatcher::OptionalMatcher
OptionalMatcher(const InnerMatcher &matcher)
Definition: clangd/unittests/Matchers.h:134
clang::clangd::SubsequenceMatcher
Definition: clangd/unittests/Matchers.h:37
clang::clangd::PolySubsequenceMatcher
Definition: clangd/unittests/Matchers.h:83
clang::clangd::PolySubsequenceMatcher::PolySubsequenceMatcher
PolySubsequenceMatcher(M &&... Args)
Definition: clangd/unittests/Matchers.h:87
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ApplyReplacements.h:27
clang::clangd::OptionalMatcher
Definition: clangd/unittests/Matchers.h:132
clang::clangd::CompletionItemKind::Value