1 //===- llvm/Testing/Support/Error.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 #ifndef LLVM_TESTING_SUPPORT_ERROR_H
10 #define LLVM_TESTING_SUPPORT_ERROR_H
11
12 #include "llvm/Support/Error.h"
13 #include "llvm/Testing/Support/SupportHelpers.h"
14
15 #include "gmock/gmock.h"
16 #include <ostream>
17
18 namespace llvm {
19 namespace detail {
20 ErrorHolder TakeError(Error Err);
21
TakeExpected(Expected<T> & Exp)22 template <typename T> ExpectedHolder<T> TakeExpected(Expected<T> &Exp) {
23 return {TakeError(Exp.takeError()), Exp};
24 }
25
TakeExpected(Expected<T> && Exp)26 template <typename T> ExpectedHolder<T> TakeExpected(Expected<T> &&Exp) {
27 return TakeExpected(Exp);
28 }
29
30 template <typename T>
31 class ValueMatchesMono
32 : public testing::MatcherInterface<const ExpectedHolder<T> &> {
33 public:
ValueMatchesMono(const testing::Matcher<T> & Matcher)34 explicit ValueMatchesMono(const testing::Matcher<T> &Matcher)
35 : Matcher(Matcher) {}
36
MatchAndExplain(const ExpectedHolder<T> & Holder,testing::MatchResultListener * listener)37 bool MatchAndExplain(const ExpectedHolder<T> &Holder,
38 testing::MatchResultListener *listener) const override {
39 if (!Holder.Success())
40 return false;
41
42 bool result = Matcher.MatchAndExplain(*Holder.Exp, listener);
43
44 if (result || !listener->IsInterested())
45 return result;
46 *listener << "(";
47 Matcher.DescribeNegationTo(listener->stream());
48 *listener << ")";
49 return result;
50 }
51
DescribeTo(std::ostream * OS)52 void DescribeTo(std::ostream *OS) const override {
53 *OS << "succeeded with value (";
54 Matcher.DescribeTo(OS);
55 *OS << ")";
56 }
57
DescribeNegationTo(std::ostream * OS)58 void DescribeNegationTo(std::ostream *OS) const override {
59 *OS << "did not succeed or value (";
60 Matcher.DescribeNegationTo(OS);
61 *OS << ")";
62 }
63
64 private:
65 testing::Matcher<T> Matcher;
66 };
67
68 template<typename M>
69 class ValueMatchesPoly {
70 public:
ValueMatchesPoly(const M & Matcher)71 explicit ValueMatchesPoly(const M &Matcher) : Matcher(Matcher) {}
72
73 template <typename T>
74 operator testing::Matcher<const ExpectedHolder<T> &>() const {
75 return MakeMatcher(
76 new ValueMatchesMono<T>(testing::SafeMatcherCast<T>(Matcher)));
77 }
78
79 private:
80 M Matcher;
81 };
82
83 template <typename InfoT>
84 class ErrorMatchesMono : public testing::MatcherInterface<const ErrorHolder &> {
85 public:
ErrorMatchesMono(std::optional<testing::Matcher<InfoT &>> Matcher)86 explicit ErrorMatchesMono(std::optional<testing::Matcher<InfoT &>> Matcher)
87 : Matcher(std::move(Matcher)) {}
88
MatchAndExplain(const ErrorHolder & Holder,testing::MatchResultListener * listener)89 bool MatchAndExplain(const ErrorHolder &Holder,
90 testing::MatchResultListener *listener) const override {
91 if (Holder.Success())
92 return false;
93
94 if (Holder.Infos.size() > 1) {
95 *listener << "multiple errors";
96 return false;
97 }
98
99 auto &Info = *Holder.Infos[0];
100 if (!Info.isA<InfoT>()) {
101 *listener << "Error was not of given type";
102 return false;
103 }
104
105 if (!Matcher)
106 return true;
107
108 return Matcher->MatchAndExplain(static_cast<InfoT &>(Info), listener);
109 }
110
DescribeTo(std::ostream * OS)111 void DescribeTo(std::ostream *OS) const override {
112 *OS << "failed with Error of given type";
113 if (Matcher) {
114 *OS << " and the error ";
115 Matcher->DescribeTo(OS);
116 }
117 }
118
DescribeNegationTo(std::ostream * OS)119 void DescribeNegationTo(std::ostream *OS) const override {
120 *OS << "succeeded or did not fail with the error of given type";
121 if (Matcher) {
122 *OS << " or the error ";
123 Matcher->DescribeNegationTo(OS);
124 }
125 }
126
127 private:
128 std::optional<testing::Matcher<InfoT &>> Matcher;
129 };
130
131 class ErrorMessageMatches
132 : public testing::MatcherInterface<const ErrorHolder &> {
133 public:
ErrorMessageMatches(testing::Matcher<std::vector<std::string>> Matcher)134 explicit ErrorMessageMatches(
135 testing::Matcher<std::vector<std::string>> Matcher)
136 : Matcher(std::move(Matcher)) {}
137
MatchAndExplain(const ErrorHolder & Holder,testing::MatchResultListener * listener)138 bool MatchAndExplain(const ErrorHolder &Holder,
139 testing::MatchResultListener *listener) const override {
140 std::vector<std::string> Messages;
141 Messages.reserve(Holder.Infos.size());
142 for (const std::shared_ptr<ErrorInfoBase> &Info : Holder.Infos)
143 Messages.push_back(Info->message());
144
145 return Matcher.MatchAndExplain(Messages, listener);
146 }
147
DescribeTo(std::ostream * OS)148 void DescribeTo(std::ostream *OS) const override {
149 *OS << "failed with Error whose message ";
150 Matcher.DescribeTo(OS);
151 }
152
DescribeNegationTo(std::ostream * OS)153 void DescribeNegationTo(std::ostream *OS) const override {
154 *OS << "failed with an Error whose message ";
155 Matcher.DescribeNegationTo(OS);
156 }
157
158 private:
159 testing::Matcher<std::vector<std::string>> Matcher;
160 };
161 } // namespace detail
162
163 #define EXPECT_THAT_ERROR(Err, Matcher) \
164 EXPECT_THAT(llvm::detail::TakeError(Err), Matcher)
165 #define ASSERT_THAT_ERROR(Err, Matcher) \
166 ASSERT_THAT(llvm::detail::TakeError(Err), Matcher)
167
168 /// Helper macro for checking the result of an 'Expected<T>'
169 ///
170 /// @code{.cpp}
171 /// // function to be tested
172 /// Expected<int> myDivide(int A, int B);
173 ///
174 /// TEST(myDivideTests, GoodAndBad) {
175 /// // test good case
176 /// // if you only care about success or failure:
177 /// EXPECT_THAT_EXPECTED(myDivide(10, 5), Succeeded());
178 /// // if you also care about the value:
179 /// EXPECT_THAT_EXPECTED(myDivide(10, 5), HasValue(2));
180 ///
181 /// // test the error case
182 /// EXPECT_THAT_EXPECTED(myDivide(10, 0), Failed());
183 /// // also check the error message
184 /// EXPECT_THAT_EXPECTED(myDivide(10, 0),
185 /// FailedWithMessage("B must not be zero!"));
186 /// }
187 /// @endcode
188
189 #define EXPECT_THAT_EXPECTED(Err, Matcher) \
190 EXPECT_THAT(llvm::detail::TakeExpected(Err), Matcher)
191 #define ASSERT_THAT_EXPECTED(Err, Matcher) \
192 ASSERT_THAT(llvm::detail::TakeExpected(Err), Matcher)
193
194 MATCHER(Succeeded, "") { return arg.Success(); }
195 MATCHER(Failed, "") { return !arg.Success(); }
196
197 template <typename InfoT>
Failed()198 testing::Matcher<const detail::ErrorHolder &> Failed() {
199 return MakeMatcher(new detail::ErrorMatchesMono<InfoT>(std::nullopt));
200 }
201
202 template <typename InfoT, typename M>
Failed(M Matcher)203 testing::Matcher<const detail::ErrorHolder &> Failed(M Matcher) {
204 return MakeMatcher(new detail::ErrorMatchesMono<InfoT>(
205 testing::SafeMatcherCast<InfoT &>(Matcher)));
206 }
207
208 template <typename... M>
FailedWithMessage(M...Matcher)209 testing::Matcher<const detail::ErrorHolder &> FailedWithMessage(M... Matcher) {
210 static_assert(sizeof...(M) > 0);
211 return MakeMatcher(
212 new detail::ErrorMessageMatches(testing::ElementsAre(Matcher...)));
213 }
214
215 template <typename M>
FailedWithMessageArray(M Matcher)216 testing::Matcher<const detail::ErrorHolder &> FailedWithMessageArray(M Matcher) {
217 return MakeMatcher(new detail::ErrorMessageMatches(Matcher));
218 }
219
220 template <typename M>
HasValue(M Matcher)221 detail::ValueMatchesPoly<M> HasValue(M Matcher) {
222 return detail::ValueMatchesPoly<M>(Matcher);
223 }
224
225 } // namespace llvm
226
227 #endif
228