Googletest export
Add ::testing::FieldsAre matcher for objects that support get<> and structured bindings.
PiperOrigin-RevId: 337165285
diff --git a/googlemock/docs/cheat_sheet.md b/googlemock/docs/cheat_sheet.md
index 78871bf..e6cffd0 100644
--- a/googlemock/docs/cheat_sheet.md
+++ b/googlemock/docs/cheat_sheet.md
@@ -403,6 +403,7 @@
| `Field(&class::field, m)` | `argument.field` (or `argument->field` when `argument` is a plain pointer) matches matcher `m`, where `argument` is an object of type _class_. |
| `Key(e)` | `argument.first` matches `e`, which can be either a value or a matcher. E.g. `Contains(Key(Le(5)))` can verify that a `map` contains a key `<= 5`. |
| `Pair(m1, m2)` | `argument` is an `std::pair` whose `first` field matches `m1` and `second` field matches `m2`. |
+| `FieldsAre(m...)` | `argument` is a compatible object where each field matches piecewise with `m...`. A compatible object is any that supports the `std::tuple_size<Obj>`+`get<I>(obj)` protocol. In C++17 and up this also supports types compatible with structured bindings, like aggregates. |
| `Property(&class::property, m)` | `argument.property()` (or `argument->property()` when `argument` is a plain pointer) matches matcher `m`, where `argument` is an object of type _class_. |
<!-- mdformat on -->
diff --git a/googlemock/include/gmock/gmock-matchers.h b/googlemock/include/gmock/gmock-matchers.h
index a897611..696f9e8 100644
--- a/googlemock/include/gmock/gmock-matchers.h
+++ b/googlemock/include/gmock/gmock-matchers.h
@@ -2879,6 +2879,203 @@
const SecondMatcher second_matcher_;
};
+template <typename T, size_t... I>
+auto UnpackStructImpl(const T& t, IndexSequence<I...>, int)
+ -> decltype(std::tie(get<I>(t)...)) {
+ static_assert(std::tuple_size<T>::value == sizeof...(I),
+ "Number of arguments doesn't match the number of fields.");
+ return std::tie(get<I>(t)...);
+}
+
+#if defined(__cpp_structured_bindings) && __cpp_structured_bindings >= 201606
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<1>, char) {
+ const auto& [a] = t;
+ return std::tie(a);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<2>, char) {
+ const auto& [a, b] = t;
+ return std::tie(a, b);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<3>, char) {
+ const auto& [a, b, c] = t;
+ return std::tie(a, b, c);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<4>, char) {
+ const auto& [a, b, c, d] = t;
+ return std::tie(a, b, c, d);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<5>, char) {
+ const auto& [a, b, c, d, e] = t;
+ return std::tie(a, b, c, d, e);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<6>, char) {
+ const auto& [a, b, c, d, e, f] = t;
+ return std::tie(a, b, c, d, e, f);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<7>, char) {
+ const auto& [a, b, c, d, e, f, g] = t;
+ return std::tie(a, b, c, d, e, f, g);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<8>, char) {
+ const auto& [a, b, c, d, e, f, g, h] = t;
+ return std::tie(a, b, c, d, e, f, g, h);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<9>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<10>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i, j] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i, j);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<11>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i, j, k] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i, j, k);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<12>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i, j, k, l] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i, j, k, l);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<13>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<14>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<15>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o);
+}
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<16>, char) {
+ const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p] = t;
+ return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p);
+}
+#endif // defined(__cpp_structured_bindings)
+
+template <size_t I, typename T>
+auto UnpackStruct(const T& t)
+ -> decltype((UnpackStructImpl)(t, MakeIndexSequence<I>{}, 0)) {
+ return (UnpackStructImpl)(t, MakeIndexSequence<I>{}, 0);
+}
+
+// Helper function to do comma folding in C++11.
+// The array ensures left-to-right order of evaluation.
+// Usage: VariadicExpand({expr...});
+template <typename T, size_t N>
+void VariadicExpand(const T (&a)[N]) {}
+
+template <typename Struct, typename StructSize>
+class FieldsAreMatcherImpl;
+
+template <typename Struct, size_t... I>
+class FieldsAreMatcherImpl<Struct, IndexSequence<I...>>
+ : public MatcherInterface<Struct> {
+ using UnpackedType =
+ decltype(UnpackStruct<sizeof...(I)>(std::declval<const Struct&>()));
+ using MatchersType = std::tuple<
+ Matcher<const typename std::tuple_element<I, UnpackedType>::type&>...>;
+
+ public:
+ template <typename Inner>
+ explicit FieldsAreMatcherImpl(const Inner& matchers)
+ : matchers_(testing::SafeMatcherCast<
+ const typename std::tuple_element<I, UnpackedType>::type&>(
+ std::get<I>(matchers))...) {}
+
+ void DescribeTo(::std::ostream* os) const override {
+ const char* separator = "";
+ VariadicExpand(
+ {(*os << separator << "has field #" << I << " that ",
+ std::get<I>(matchers_).DescribeTo(os), separator = ", and ")...});
+ }
+
+ void DescribeNegationTo(::std::ostream* os) const override {
+ const char* separator = "";
+ VariadicExpand({(*os << separator << "has field #" << I << " that ",
+ std::get<I>(matchers_).DescribeNegationTo(os),
+ separator = ", or ")...});
+ }
+
+ bool MatchAndExplain(Struct t, MatchResultListener* listener) const override {
+ return MatchInternal((UnpackStruct<sizeof...(I)>)(t), listener);
+ }
+
+ private:
+ bool MatchInternal(UnpackedType tuple, MatchResultListener* listener) const {
+ if (!listener->IsInterested()) {
+ // If the listener is not interested, we don't need to construct the
+ // explanation.
+ bool good = true;
+ VariadicExpand({good = good && std::get<I>(matchers_).Matches(
+ std::get<I>(tuple))...});
+ return good;
+ }
+
+ int failed_pos = -1;
+
+ std::vector<StringMatchResultListener> inner_listener(sizeof...(I));
+
+ VariadicExpand(
+ {failed_pos == -1 && !std::get<I>(matchers_).MatchAndExplain(
+ std::get<I>(tuple), &inner_listener[I])
+ ? failed_pos = I
+ : 0 ...});
+ if (failed_pos != ~size_t{}) {
+ *listener << "whose field #" << failed_pos << " does not match";
+ PrintIfNotEmpty(inner_listener[failed_pos].str(), listener->stream());
+ return false;
+ }
+
+ *listener << "whose all elements match";
+ const char* separator = ", where";
+ for (size_t index = 0; index < sizeof...(I); ++index) {
+ const std::string str = inner_listener[index].str();
+ if (!str.empty()) {
+ *listener << separator << " field #" << index << " is a value " << str;
+ separator = ", and";
+ }
+ }
+
+ return true;
+ }
+
+ MatchersType matchers_;
+};
+
+template <typename... Inner>
+class FieldsAreMatcher {
+ public:
+ explicit FieldsAreMatcher(Inner... inner) : matchers_(std::move(inner)...) {}
+
+ template <typename Struct>
+ operator Matcher<Struct>() const { // NOLINT
+ return Matcher<Struct>(
+ new FieldsAreMatcherImpl<const Struct&, IndexSequenceFor<Inner...>>(
+ matchers_));
+ }
+
+ private:
+ std::tuple<Inner...> matchers_;
+};
+
// Implements ElementsAre() and ElementsAreArray().
template <typename Container>
class ElementsAreMatcherImpl : public MatcherInterface<Container> {
@@ -4514,6 +4711,19 @@
first_matcher, second_matcher);
}
+namespace no_adl {
+// FieldsAre(matchers...) matches piecewise the fields of compatible structs.
+// These include those that support `get<I>(obj)`, and when structured bindings
+// are enabled any class that supports them.
+// In particular, `std::tuple`, `std::pair`, `std::array` and aggregate types.
+template <typename... M>
+internal::FieldsAreMatcher<typename std::decay<M>::type...> FieldsAre(
+ M&&... matchers) {
+ return internal::FieldsAreMatcher<typename std::decay<M>::type...>(
+ std::forward<M>(matchers)...);
+}
+} // namespace no_adl
+
// Returns a predicate that is satisfied by anything that matches the
// given matcher.
template <typename M>
@@ -5053,6 +5263,9 @@
#define GMOCK_INTERNAL_MATCHER_ARG_USAGE(i, data_unused, arg_unused) \
, gmock_p##i
+// To prevent ADL on certain functions we put them on a separate namespace.
+using namespace no_adl; // NOLINT
+
} // namespace testing
GTEST_DISABLE_MSC_WARNINGS_POP_() // 4251 5046
diff --git a/googlemock/test/gmock-matchers_test.cc b/googlemock/test/gmock-matchers_test.cc
index 1cba156..0ce5b58 100644
--- a/googlemock/test/gmock-matchers_test.cc
+++ b/googlemock/test/gmock-matchers_test.cc
@@ -1643,6 +1643,147 @@
EXPECT_THAT(container, Not(Contains(Pair(3, _))));
}
+TEST(FieldsAreTest, MatchesCorrectly) {
+ std::tuple<int, std::string, double> p(25, "foo", .5);
+
+ // All fields match.
+ EXPECT_THAT(p, FieldsAre(25, "foo", .5));
+ EXPECT_THAT(p, FieldsAre(Ge(20), HasSubstr("o"), DoubleEq(.5)));
+
+ // Some don't match.
+ EXPECT_THAT(p, Not(FieldsAre(26, "foo", .5)));
+ EXPECT_THAT(p, Not(FieldsAre(25, "fo", .5)));
+ EXPECT_THAT(p, Not(FieldsAre(25, "foo", .6)));
+}
+
+TEST(FieldsAreTest, CanDescribeSelf) {
+ Matcher<const pair<std::string, int>&> m1 = FieldsAre("foo", 42);
+ EXPECT_EQ(
+ "has field #0 that is equal to \"foo\""
+ ", and has field #1 that is equal to 42",
+ Describe(m1));
+ EXPECT_EQ(
+ "has field #0 that isn't equal to \"foo\""
+ ", or has field #1 that isn't equal to 42",
+ DescribeNegation(m1));
+}
+
+TEST(FieldsAreTest, CanExplainMatchResultTo) {
+ // The first one that fails is the one that gives the error.
+ Matcher<std::tuple<int, int, int>> m =
+ FieldsAre(GreaterThan(0), GreaterThan(0), GreaterThan(0));
+
+ EXPECT_EQ("whose field #0 does not match, which is 1 less than 0",
+ Explain(m, std::make_tuple(-1, -2, -3)));
+ EXPECT_EQ("whose field #1 does not match, which is 2 less than 0",
+ Explain(m, std::make_tuple(1, -2, -3)));
+ EXPECT_EQ("whose field #2 does not match, which is 3 less than 0",
+ Explain(m, std::make_tuple(1, 2, -3)));
+
+ // If they all match, we get a long explanation of success.
+ EXPECT_EQ(
+ "whose all elements match, "
+ "where field #0 is a value which is 1 more than 0"
+ ", and field #1 is a value which is 2 more than 0"
+ ", and field #2 is a value which is 3 more than 0",
+ Explain(m, std::make_tuple(1, 2, 3)));
+
+ // Only print those that have an explanation.
+ m = FieldsAre(GreaterThan(0), 0, GreaterThan(0));
+ EXPECT_EQ(
+ "whose all elements match, "
+ "where field #0 is a value which is 1 more than 0"
+ ", and field #2 is a value which is 3 more than 0",
+ Explain(m, std::make_tuple(1, 0, 3)));
+
+ // If only one has an explanation, then print that one.
+ m = FieldsAre(0, GreaterThan(0), 0);
+ EXPECT_EQ(
+ "whose all elements match, "
+ "where field #1 is a value which is 1 more than 0",
+ Explain(m, std::make_tuple(0, 1, 0)));
+}
+
+#if defined(__cpp_structured_bindings) && __cpp_structured_bindings >= 201606
+TEST(FieldsAreTest, StructuredBindings) {
+ // testing::FieldsAre can also match aggregates and such with C++17 and up.
+ struct MyType {
+ int i;
+ std::string str;
+ };
+ EXPECT_THAT((MyType{17, "foo"}), FieldsAre(Eq(17), HasSubstr("oo")));
+
+ // Test all the supported arities.
+ struct MyVarType1 {
+ int a;
+ };
+ EXPECT_THAT(MyVarType1{}, FieldsAre(0));
+ struct MyVarType2 {
+ int a, b;
+ };
+ EXPECT_THAT(MyVarType2{}, FieldsAre(0, 0));
+ struct MyVarType3 {
+ int a, b, c;
+ };
+ EXPECT_THAT(MyVarType3{}, FieldsAre(0, 0, 0));
+ struct MyVarType4 {
+ int a, b, c, d;
+ };
+ EXPECT_THAT(MyVarType4{}, FieldsAre(0, 0, 0, 0));
+ struct MyVarType5 {
+ int a, b, c, d, e;
+ };
+ EXPECT_THAT(MyVarType5{}, FieldsAre(0, 0, 0, 0, 0));
+ struct MyVarType6 {
+ int a, b, c, d, e, f;
+ };
+ EXPECT_THAT(MyVarType6{}, FieldsAre(0, 0, 0, 0, 0, 0));
+ struct MyVarType7 {
+ int a, b, c, d, e, f, g;
+ };
+ EXPECT_THAT(MyVarType7{}, FieldsAre(0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType8 {
+ int a, b, c, d, e, f, g, h;
+ };
+ EXPECT_THAT(MyVarType8{}, FieldsAre(0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType9 {
+ int a, b, c, d, e, f, g, h, i;
+ };
+ EXPECT_THAT(MyVarType9{}, FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType10 {
+ int a, b, c, d, e, f, g, h, i, j;
+ };
+ EXPECT_THAT(MyVarType10{}, FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType11 {
+ int a, b, c, d, e, f, g, h, i, j, k;
+ };
+ EXPECT_THAT(MyVarType11{}, FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType12 {
+ int a, b, c, d, e, f, g, h, i, j, k, l;
+ };
+ EXPECT_THAT(MyVarType12{}, FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType13 {
+ int a, b, c, d, e, f, g, h, i, j, k, l, m;
+ };
+ EXPECT_THAT(MyVarType13{}, FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType14 {
+ int a, b, c, d, e, f, g, h, i, j, k, l, m, n;
+ };
+ EXPECT_THAT(MyVarType14{},
+ FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType15 {
+ int a, b, c, d, e, f, g, h, i, j, k, l, m, n, o;
+ };
+ EXPECT_THAT(MyVarType15{},
+ FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+ struct MyVarType16 {
+ int a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p;
+ };
+ EXPECT_THAT(MyVarType16{},
+ FieldsAre(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+}
+#endif
+
TEST(ContainsTest, WorksWithMoveOnly) {
ContainerHelper helper;
EXPECT_CALL(helper, Call(Contains(Pointee(2))));
diff --git a/googletest/include/gtest/internal/gtest-internal.h b/googletest/include/gtest/internal/gtest-internal.h
index 959f6fc..0500dea 100644
--- a/googletest/include/gtest/internal/gtest-internal.h
+++ b/googletest/include/gtest/internal/gtest-internal.h
@@ -1178,12 +1178,18 @@
// Backport of std::make_index_sequence.
// It uses O(ln(N)) instantiation depth.
template <size_t N>
-struct MakeIndexSequence
- : DoubleSequence<N % 2 == 1, typename MakeIndexSequence<N / 2>::type,
+struct MakeIndexSequenceImpl
+ : DoubleSequence<N % 2 == 1, typename MakeIndexSequenceImpl<N / 2>::type,
N / 2>::type {};
template <>
-struct MakeIndexSequence<0> : IndexSequence<> {};
+struct MakeIndexSequenceImpl<0> : IndexSequence<> {};
+
+template <size_t N>
+using MakeIndexSequence = typename MakeIndexSequenceImpl<N>::type;
+
+template <typename... T>
+using IndexSequenceFor = typename MakeIndexSequence<sizeof...(T)>::type;
template <size_t>
struct Ignore {
