Add GoogleTest matchers for absl::Status

PiperOrigin-RevId: 630072639
Change-Id: Ibbb166cc3c0479617c8e48abe8134b59a67a578f

6 files changed, 623 insertions, 0 deletions

diff --git a/absl/status/BUILD.bazel b/absl/status/BUILD.bazel
index 981b37fd..810a3dda 100644
--- a/absl/status/BUILD.bazel
+++ b/absl/status/BUILD.bazel
@@ -129,3 +129,38 @@ cc_test(
         "@com_google_googletest//:gtest_main",
     ],
 )
+
+cc_library(
+    name = "status_matchers",
+    testonly = 1,
+    srcs = [
+        "internal/status_matchers.cc",
+        "internal/status_matchers.h",
+    ],
+    hdrs = ["status_matchers.h"],
+    copts = ABSL_DEFAULT_COPTS,
+    linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = [
+        ":status",
+        ":statusor",
+        "//absl/base:config",
+        "//absl/strings:string_view",
+        "@com_google_googletest//:gtest",
+    ],
+)
+
+cc_test(
+    name = "status_matchers_test",
+    size = "small",
+    srcs = ["status_matchers_test.cc"],
+    copts = ABSL_TEST_COPTS,
+    linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = [
+        ":status",
+        ":status_matchers",
+        ":statusor",
+        "//absl/strings",
+        "@com_google_googletest//:gtest",
+        "@com_google_googletest//:gtest_main",
+    ],
+)
diff --git a/absl/status/CMakeLists.txt b/absl/status/CMakeLists.txt
index 00415ab9..d9f04695 100644
--- a/absl/status/CMakeLists.txt
+++ b/absl/status/CMakeLists.txt
@@ -102,3 +102,40 @@ absl_cc_test(
     absl::strings
     GTest::gmock_main
 )
+
+absl_cc_library(
+  NAME
+    status_matchers
+  HDRS
+    "status_matchers.h"
+  SRCS
+    "internal/status_matchers.h"
+    "internal/status_matchers.cc"
+  COPTS
+    ${ABSL_DEFAULT_COPTS}
+  LINKOPTS
+    ${ABSL_DEFAULT_LINKOPTS}
+  DEPS
+    absl::base
+    absl::status
+    absl::statusor
+    absl::strings
+    GTest::gmock
+    GTest::gtest
+  PUBLIC
+  TESTONLY
+)
+
+absl_cc_test(
+  NAME
+    status_matchers_test
+  SRCS
+   "status_matchers_test.cc"
+  COPTS
+    ${ABSL_TEST_COPTS}
+  DEPS
+    absl::status
+    absl::statusor
+    absl::status_matchers
+    GTest::gmock_main
+)
diff --git a/absl/status/internal/status_matchers.cc b/absl/status/internal/status_matchers.cc
new file mode 100644
index 00000000..86e239e5
--- /dev/null
+++ b/absl/status/internal/status_matchers.cc
@@ -0,0 +1,68 @@
+// Copyright 2024 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: status_matchers.cc
+// -----------------------------------------------------------------------------
+
+#include "absl/status/internal/status_matchers.h"
+
+#include <ostream>
+#include <string>
+
+#include "gmock/gmock.h"
+#include "absl/base/config.h"
+#include "absl/status/status.h"
+
+namespace absl_testing {
+ABSL_NAMESPACE_BEGIN
+namespace status_internal {
+
+void StatusIsMatcherCommonImpl::DescribeTo(std::ostream* os) const {
+  *os << ", has a status code that ";
+  code_matcher_.DescribeTo(os);
+  *os << ", and has an error message that ";
+  message_matcher_.DescribeTo(os);
+}
+
+void StatusIsMatcherCommonImpl::DescribeNegationTo(std::ostream* os) const {
+  *os << ", or has a status code that ";
+  code_matcher_.DescribeNegationTo(os);
+  *os << ", or has an error message that ";
+  message_matcher_.DescribeNegationTo(os);
+}
+
+bool StatusIsMatcherCommonImpl::MatchAndExplain(
+    const ::absl::Status& status,
+    ::testing::MatchResultListener* result_listener) const {
+  ::testing::StringMatchResultListener inner_listener;
+  if (!code_matcher_.MatchAndExplain(status.code(), &inner_listener)) {
+    *result_listener << (inner_listener.str().empty()
+                             ? "whose status code is wrong"
+                             : "which has a status code " +
+                                   inner_listener.str());
+    return false;
+  }
+
+  if (!message_matcher_.Matches(std::string(status.message()))) {
+    *result_listener << "whose error message is wrong";
+    return false;
+  }
+
+  return true;
+}
+
+}  // namespace status_internal
+ABSL_NAMESPACE_END
+}  // namespace absl_testing
diff --git a/absl/status/internal/status_matchers.h b/absl/status/internal/status_matchers.h
new file mode 100644
index 00000000..ab0b304e
--- /dev/null
+++ b/absl/status/internal/status_matchers.h
@@ -0,0 +1,246 @@
+// Copyright 2024 The Abseil Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef ABSL_STATUS_INTERNAL_STATUS_MATCHERS_H_
+#define ABSL_STATUS_INTERNAL_STATUS_MATCHERS_H_
+
+#include <ostream>  // NOLINT
+#include <string>
+#include <type_traits>
+#include <utility>
+
+#include "gmock/gmock.h"
+#include "absl/base/config.h"
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+#include "absl/strings/string_view.h"
+
+namespace absl_testing {
+ABSL_NAMESPACE_BEGIN
+namespace status_internal {
+
+inline const absl::Status& GetStatus(const absl::Status& status) {
+  return status;
+}
+
+template <typename T>
+inline const absl::Status& GetStatus(const absl::StatusOr<T>& status) {
+  return status.status();
+}
+
+////////////////////////////////////////////////////////////
+// Implementation of IsOkAndHolds().
+
+// Monomorphic implementation of matcher IsOkAndHolds(m).  StatusOrType is a
+// reference to StatusOr<T>.
+template <typename StatusOrType>
+class IsOkAndHoldsMatcherImpl
+    : public ::testing::MatcherInterface<StatusOrType> {
+ public:
+  typedef
+      typename std::remove_reference<StatusOrType>::type::value_type value_type;
+
+  template <typename InnerMatcher>
+  explicit IsOkAndHoldsMatcherImpl(InnerMatcher&& inner_matcher)
+      : inner_matcher_(::testing::SafeMatcherCast<const value_type&>(
+            std::forward<InnerMatcher>(inner_matcher))) {}
+
+  void DescribeTo(std::ostream* os) const override {
+    *os << "is OK and has a value that ";
+    inner_matcher_.DescribeTo(os);
+  }
+
+  void DescribeNegationTo(std::ostream* os) const override {
+    *os << "isn't OK or has a value that ";
+    inner_matcher_.DescribeNegationTo(os);
+  }
+
+  bool MatchAndExplain(
+      StatusOrType actual_value,
+      ::testing::MatchResultListener* result_listener) const override {
+    if (!actual_value.ok()) {
+      *result_listener << "which has status " << actual_value.status();
+      return false;
+    }
+
+    // Call through to the inner matcher.
+    return inner_matcher_.MatchAndExplain(*actual_value, result_listener);
+  }
+
+ private:
+  const ::testing::Matcher<const value_type&> inner_matcher_;
+};
+
+// Implements IsOkAndHolds(m) as a polymorphic matcher.
+template <typename InnerMatcher>
+class IsOkAndHoldsMatcher {
+ public:
+  explicit IsOkAndHoldsMatcher(InnerMatcher inner_matcher)
+      : inner_matcher_(std::forward<InnerMatcher>(inner_matcher)) {}
+
+  // Converts this polymorphic matcher to a monomorphic matcher of the
+  // given type.  StatusOrType can be either StatusOr<T> or a
+  // reference to StatusOr<T>.
+  template <typename StatusOrType>
+  operator ::testing::Matcher<StatusOrType>() const {  // NOLINT
+    return ::testing::Matcher<StatusOrType>(
+        new IsOkAndHoldsMatcherImpl<const StatusOrType&>(inner_matcher_));
+  }
+
+ private:
+  const InnerMatcher inner_matcher_;
+};
+
+////////////////////////////////////////////////////////////
+// Implementation of StatusIs().
+
+// `StatusCode` is implicitly convertible from `int`, `absl::StatusCode`, and
+//  is explicitly convertible to these types as well.
+//
+// We need this class because `absl::StatusCode` (as a scoped enum) is not
+// implicitly convertible to `int`. In order to handle use cases like
+// ```
+// StatusIs(Anyof(absl::StatusCode::kUnknown, absl::StatusCode::kCancelled))
+// ```
+// which uses polymorphic matchers, we need to unify the interfaces into
+// `Matcher<StatusCode>`.
+class StatusCode {
+ public:
+  /*implicit*/ StatusCode(int code)  // NOLINT
+      : code_(static_cast<::absl::StatusCode>(code)) {}
+  /*implicit*/ StatusCode(::absl::StatusCode code) : code_(code) {}  // NOLINT
+
+  explicit operator int() const { return static_cast<int>(code_); }
+
+  friend inline void PrintTo(const StatusCode& code, std::ostream* os) {
+    // TODO(b/321095377): Change this to print the status code as a string.
+    *os << static_cast<int>(code);
+  }
+
+ private:
+  ::absl::StatusCode code_;
+};
+
+// Relational operators to handle matchers like Eq, Lt, etc..
+inline bool operator==(const StatusCode& lhs, const StatusCode& rhs) {
+  return static_cast<int>(lhs) == static_cast<int>(rhs);
+}
+inline bool operator!=(const StatusCode& lhs, const StatusCode& rhs) {
+  return static_cast<int>(lhs) != static_cast<int>(rhs);
+}
+
+// StatusIs() is a polymorphic matcher.  This class is the common
+// implementation of it shared by all types T where StatusIs() can be
+// used as a Matcher<T>.
+class StatusIsMatcherCommonImpl {
+ public:
+  StatusIsMatcherCommonImpl(
+      ::testing::Matcher<StatusCode> code_matcher,
+      ::testing::Matcher<absl::string_view> message_matcher)
+      : code_matcher_(std::move(code_matcher)),
+        message_matcher_(std::move(message_matcher)) {}
+
+  void DescribeTo(std::ostream* os) const;
+
+  void DescribeNegationTo(std::ostream* os) const;
+
+  bool MatchAndExplain(const absl::Status& status,
+                       ::testing::MatchResultListener* result_listener) const;
+
+ private:
+  const ::testing::Matcher<StatusCode> code_matcher_;
+  const ::testing::Matcher<absl::string_view> message_matcher_;
+};
+
+// Monomorphic implementation of matcher StatusIs() for a given type
+// T.  T can be Status, StatusOr<>, or a reference to either of them.
+template <typename T>
+class MonoStatusIsMatcherImpl : public ::testing::MatcherInterface<T> {
+ public:
+  explicit MonoStatusIsMatcherImpl(StatusIsMatcherCommonImpl common_impl)
+      : common_impl_(std::move(common_impl)) {}
+
+  void DescribeTo(std::ostream* os) const override {
+    common_impl_.DescribeTo(os);
+  }
+
+  void DescribeNegationTo(std::ostream* os) const override {
+    common_impl_.DescribeNegationTo(os);
+  }
+
+  bool MatchAndExplain(
+      T actual_value,
+      ::testing::MatchResultListener* result_listener) const override {
+    return common_impl_.MatchAndExplain(GetStatus(actual_value),
+                                        result_listener);
+  }
+
+ private:
+  StatusIsMatcherCommonImpl common_impl_;
+};
+
+// Implements StatusIs() as a polymorphic matcher.
+class StatusIsMatcher {
+ public:
+  template <typename StatusCodeMatcher, typename StatusMessageMatcher>
+  StatusIsMatcher(StatusCodeMatcher&& code_matcher,
+                  StatusMessageMatcher&& message_matcher)
+      : common_impl_(::testing::MatcherCast<StatusCode>(
+                         std::forward<StatusCodeMatcher>(code_matcher)),
+                     ::testing::MatcherCast<absl::string_view>(
+                         std::forward<StatusMessageMatcher>(message_matcher))) {
+  }
+
+  // Converts this polymorphic matcher to a monomorphic matcher of the
+  // given type.  T can be StatusOr<>, Status, or a reference to
+  // either of them.
+  template <typename T>
+  /*implicit*/ operator ::testing::Matcher<T>() const {  // NOLINT
+    return ::testing::Matcher<T>(
+        new MonoStatusIsMatcherImpl<const T&>(common_impl_));
+  }
+
+ private:
+  const StatusIsMatcherCommonImpl common_impl_;
+};
+
+// Monomorphic implementation of matcher IsOk() for a given type T.
+// T can be Status, StatusOr<>, or a reference to either of them.
+template <typename T>
+class MonoIsOkMatcherImpl : public ::testing::MatcherInterface<T> {
+ public:
+  void DescribeTo(std::ostream* os) const override { *os << "is OK"; }
+  void DescribeNegationTo(std::ostream* os) const override {
+    *os << "is not OK";
+  }
+  bool MatchAndExplain(T actual_value,
+                       ::testing::MatchResultListener*) const override {
+    return GetStatus(actual_value).ok();
+  }
+};
+
+// Implements IsOk() as a polymorphic matcher.
+class IsOkMatcher {
+ public:
+  template <typename T>
+  /*implicit*/ operator ::testing::Matcher<T>() const {  // NOLINT
+    return ::testing::Matcher<T>(new MonoIsOkMatcherImpl<const T&>());
+  }
+};
+
+}  // namespace status_internal
+ABSL_NAMESPACE_END
+}  // namespace absl_testing
+
+#endif  // ABSL_STATUS_INTERNAL_STATUS_MATCHERS_H_
diff --git a/absl/status/status_matchers.h b/absl/status/status_matchers.h
new file mode 100644
index 00000000..66201f27
--- /dev/null
+++ b/absl/status/status_matchers.h
@@ -0,0 +1,118 @@
+// Copyright 2024 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: status_matchers.h
+// -----------------------------------------------------------------------------
+//
+// Testing utilities for working with `absl::Status` and `absl::StatusOr`.
+//
+// Defines the following utilities:
+//
+//   ===============
+//   `IsOkAndHolds(m)`
+//   ===============
+//
+//   This gMock matcher matches a StatusOr<T> value whose status is OK
+//   and whose inner value matches matcher m.  Example:
+//
+//   ```
+//   using ::testing::MatchesRegex;
+//   using ::absl_testing::IsOkAndHolds;
+//   ...
+//   absl::StatusOr<string> maybe_name = ...;
+//   EXPECT_THAT(maybe_name, IsOkAndHolds(MatchesRegex("John .*")));
+//   ```
+//
+//   ===============================
+//   `StatusIs(status_code_matcher)`
+//   ===============================
+//
+//   This is a shorthand for
+//     `StatusIs(status_code_matcher, ::testing::_)`
+//   In other words, it's like the two-argument `StatusIs()`, except that it
+//   ignores error message.
+//
+//   ===============
+//   `IsOk()`
+//   ===============
+//
+//   Matches an `absl::Status` or `absl::StatusOr<T>` value whose status value
+//   is `absl::StatusCode::kOk.`
+//
+//   Equivalent to 'StatusIs(absl::StatusCode::kOk)'.
+//   Example:
+//   ```
+//   using ::absl_testing::IsOk;
+//   ...
+//   absl::StatusOr<string> maybe_name = ...;
+//   EXPECT_THAT(maybe_name, IsOk());
+//   Status s = ...;
+//   EXPECT_THAT(s, IsOk());
+//   ```
+
+#ifndef ABSL_STATUS_STATUS_MATCHERS_H_
+#define ABSL_STATUS_STATUS_MATCHERS_H_
+
+#include <ostream>  // NOLINT
+#include <type_traits>
+#include <utility>
+
+#include "gmock/gmock.h"
+#include "absl/base/config.h"
+#include "absl/status/internal/status_matchers.h"
+
+namespace absl_testing {
+ABSL_NAMESPACE_BEGIN
+
+// Returns a gMock matcher that matches a StatusOr<> whose status is
+// OK and whose value matches the inner matcher.
+template <typename InnerMatcherT>
+status_internal::IsOkAndHoldsMatcher<typename std::decay<InnerMatcherT>::type>
+IsOkAndHolds(InnerMatcherT&& inner_matcher) {
+  return status_internal::IsOkAndHoldsMatcher<
+      typename std::decay<InnerMatcherT>::type>(
+      std::forward<InnerMatcherT>(inner_matcher));
+}
+
+// Returns a gMock matcher that matches a Status or StatusOr<> whose status code
+// matches code_matcher and whose error message matches message_matcher.
+// Typically, code_matcher will be an absl::StatusCode, e.g.
+//
+// StatusIs(absl::StatusCode::kInvalidArgument, "...")
+template <typename StatusCodeMatcherT, typename StatusMessageMatcherT>
+status_internal::StatusIsMatcher StatusIs(
+    StatusCodeMatcherT&& code_matcher,
+    StatusMessageMatcherT&& message_matcher) {
+  return status_internal::StatusIsMatcher(
+      std::forward<StatusCodeMatcherT>(code_matcher),
+      std::forward<StatusMessageMatcherT>(message_matcher));
+}
+
+// Returns a gMock matcher that matches a Status or StatusOr<> and whose status
+// code matches code_matcher.  See above for details.
+template <typename StatusCodeMatcherT>
+status_internal::StatusIsMatcher StatusIs(StatusCodeMatcherT&& code_matcher) {
+  return StatusIs(std::forward<StatusCodeMatcherT>(code_matcher), ::testing::_);
+}
+
+// Returns a gMock matcher that matches a Status or StatusOr<> which is OK.
+inline status_internal::IsOkMatcher IsOk() {
+  return status_internal::IsOkMatcher();
+}
+
+ABSL_NAMESPACE_END
+}  // namespace absl_testing
+
+#endif  // ABSL_STATUS_STATUS_MATCHERS_H_
diff --git a/absl/status/status_matchers_test.cc b/absl/status/status_matchers_test.cc
new file mode 100644
index 00000000..3af03053
--- /dev/null
+++ b/absl/status/status_matchers_test.cc
@@ -0,0 +1,119 @@
+// Copyright 2024 The Abseil Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: status_matchers_test.cc
+// -----------------------------------------------------------------------------
+#include "absl/status/status_matchers.h"
+
+#include "gmock/gmock.h"
+#include "gtest/gtest-spi.h"
+#include "gtest/gtest.h"
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+#include "absl/strings/string_view.h"
+
+namespace {
+
+using ::absl_testing::IsOk;
+using ::absl_testing::IsOkAndHolds;
+using ::absl_testing::StatusIs;
+using ::testing::Gt;
+
+TEST(StatusMatcherTest, StatusIsOk) { EXPECT_THAT(absl::OkStatus(), IsOk()); }
+
+TEST(StatusMatcherTest, StatusOrIsOk) {
+  absl::StatusOr<int> ok_int = {0};
+  EXPECT_THAT(ok_int, IsOk());
+}
+
+TEST(StatusMatcherTest, StatusIsNotOk) {
+  absl::Status error = absl::UnknownError("Smigla");
+  EXPECT_NONFATAL_FAILURE(EXPECT_THAT(error, IsOk()), "Smigla");
+}
+
+TEST(StatusMatcherTest, StatusOrIsNotOk) {
+  absl::StatusOr<int> error = absl::UnknownError("Smigla");
+  EXPECT_NONFATAL_FAILURE(EXPECT_THAT(error, IsOk()), "Smigla");
+}
+
+TEST(StatusMatcherTest, IsOkAndHolds) {
+  absl::StatusOr<int> ok_int = {4};
+  absl::StatusOr<absl::string_view> ok_str = {"text"};
+  EXPECT_THAT(ok_int, IsOkAndHolds(4));
+  EXPECT_THAT(ok_int, IsOkAndHolds(Gt(0)));
+  EXPECT_THAT(ok_str, IsOkAndHolds("text"));
+}
+
+TEST(StatusMatcherTest, IsOkAndHoldsFailure) {
+  absl::StatusOr<int> ok_int = {502};
+  absl::StatusOr<int> error = absl::UnknownError("Smigla");
+  absl::StatusOr<absl::string_view> ok_str = {"actual"};
+  EXPECT_NONFATAL_FAILURE(EXPECT_THAT(ok_int, IsOkAndHolds(0)), "502");
+  EXPECT_NONFATAL_FAILURE(EXPECT_THAT(error, IsOkAndHolds(0)), "Smigla");
+  EXPECT_NONFATAL_FAILURE(EXPECT_THAT(ok_str, IsOkAndHolds("expected")),
+                          "actual");
+}
+
+TEST(StatusMatcherTest, StatusIs) {
+  absl::Status unknown = absl::UnknownError("unbekannt");
+  absl::Status invalid = absl::InvalidArgumentError("ungueltig");
+  EXPECT_THAT(absl::OkStatus(), StatusIs(absl::StatusCode::kOk));
+  EXPECT_THAT(absl::OkStatus(), StatusIs(0));
+  EXPECT_THAT(unknown, StatusIs(absl::StatusCode::kUnknown));
+  EXPECT_THAT(unknown, StatusIs(2));
+  EXPECT_THAT(unknown, StatusIs(absl::StatusCode::kUnknown, "unbekannt"));
+  EXPECT_THAT(invalid, StatusIs(absl::StatusCode::kInvalidArgument));
+  EXPECT_THAT(invalid, StatusIs(3));
+  EXPECT_THAT(invalid,
+              StatusIs(absl::StatusCode::kInvalidArgument, "ungueltig"));
+}
+
+TEST(StatusMatcherTest, StatusOrIs) {
+  absl::StatusOr<int> ok = {42};
+  absl::StatusOr<int> unknown = absl::UnknownError("unbekannt");
+  absl::StatusOr<absl::string_view> invalid =
+      absl::InvalidArgumentError("ungueltig");
+  EXPECT_THAT(ok, StatusIs(absl::StatusCode::kOk));
+  EXPECT_THAT(ok, StatusIs(0));
+  EXPECT_THAT(unknown, StatusIs(absl::StatusCode::kUnknown));
+  EXPECT_THAT(unknown, StatusIs(2));
+  EXPECT_THAT(unknown, StatusIs(absl::StatusCode::kUnknown, "unbekannt"));
+  EXPECT_THAT(invalid, StatusIs(absl::StatusCode::kInvalidArgument));
+  EXPECT_THAT(invalid, StatusIs(3));
+  EXPECT_THAT(invalid,
+              StatusIs(absl::StatusCode::kInvalidArgument, "ungueltig"));
+}
+
+TEST(StatusMatcherTest, StatusIsFailure) {
+  absl::Status unknown = absl::UnknownError("unbekannt");
+  absl::Status invalid = absl::InvalidArgumentError("ungueltig");
+  EXPECT_NONFATAL_FAILURE(
+      EXPECT_THAT(absl::OkStatus(),
+                  StatusIs(absl::StatusCode::kInvalidArgument)),
+      "OK");
+  EXPECT_NONFATAL_FAILURE(
+      EXPECT_THAT(unknown, StatusIs(absl::StatusCode::kCancelled)), "UNKNOWN");
+  EXPECT_NONFATAL_FAILURE(
+      EXPECT_THAT(unknown, StatusIs(absl::StatusCode::kUnknown, "inconnu")),
+      "unbekannt");
+  EXPECT_NONFATAL_FAILURE(
+      EXPECT_THAT(invalid, StatusIs(absl::StatusCode::kOutOfRange)), "INVALID");
+  EXPECT_NONFATAL_FAILURE(
+      EXPECT_THAT(invalid,
+                  StatusIs(absl::StatusCode::kInvalidArgument, "invalide")),
+      "ungueltig");
+}
+
+}  // namespace