Add lifetime annotations to more places using StringRef

The matcher combinators do not take ownership of the matchers
being combined, which can catch the users off-guard, when code like
this

```cpp
using Catch::Matchers::EndsWith;
using Catch::Matchers::ContainsSubstring;

auto combinedMatcher = EndsWith("as a service")
                       && ContainsSubstring("web scale");

REQUIRE_THAT( getSomeString(), combinedMatcher );
```

leads to use-after-free, as the `combinedMatcher` refers to matcher
temporaries that no longer exists. With this commit, users of Clang,
MSVC or other compiler that understands the `lifetimebound` attribute,
should get a warning.

.clang-tidy

@@ -78,5 +78,5 @@ WarningsAsErrors: >-
   readability-duplicate-include,
 HeaderFilterRegex: '.*\.(c|cxx|cpp)$'
 FormatStyle:     none
-CheckOptions: {}
+CheckOptions: []
 ...

CMakeLists.txt

@@ -20,6 +20,7 @@ cmake_dependent_option(CATCH_BUILD_TESTING "Build the SelfTest project" ON "CATC
 cmake_dependent_option(CATCH_BUILD_EXAMPLES "Build code examples" OFF "CATCH_DEVELOPMENT_BUILD" OFF)
 cmake_dependent_option(CATCH_BUILD_EXTRA_TESTS "Build extra tests" OFF "CATCH_DEVELOPMENT_BUILD" OFF)
 cmake_dependent_option(CATCH_BUILD_FUZZERS "Build fuzzers" OFF "CATCH_DEVELOPMENT_BUILD" OFF)
+cmake_dependent_option(CATCH_BUILD_BENCHMARKS "Build the benchmarks" OFF "CATCH_DEVELOPMENT_BUILD" OFF)
 cmake_dependent_option(CATCH_ENABLE_COVERAGE "Generate coverage for codecov.io" OFF "CATCH_DEVELOPMENT_BUILD" OFF)
 cmake_dependent_option(CATCH_ENABLE_WERROR "Enables Werror during build" ON "CATCH_DEVELOPMENT_BUILD" OFF)
 cmake_dependent_option(CATCH_BUILD_SURROGATES "Enable generating and building surrogate TUs for the main headers" OFF "CATCH_DEVELOPMENT_BUILD" OFF)
@@ -34,7 +35,7 @@ if(CMAKE_BINARY_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
 endif()
 
 project(Catch2
-  VERSION 3.10.0 # CML version placeholder, don't delete
+  VERSION 3.11.0 # CML version placeholder, don't delete
   LANGUAGES CXX
   HOMEPAGE_URL "https://github.com/catchorg/Catch2"
   DESCRIPTION "A modern, C++-native, unit test framework."
@@ -77,6 +78,11 @@ set(SELF_TEST_DIR ${CATCH_DIR}/tests/SelfTest)
 # We need to bring-in the variables defined there to this scope
 add_subdirectory(src)
 
+if (CATCH_BUILD_BENCHMARKS)
+  set(CMAKE_FOLDER "benchmarks")
+  add_subdirectory(benchmarks)
+endif()
+
 # Build tests only if requested
 if(BUILD_TESTING AND CATCH_BUILD_TESTING AND NOT_SUBPROJECT)
   find_package(Python3 REQUIRED COMPONENTS Interpreter)

CMakePresets.json

@@ -15,14 +15,23 @@
             }
         },
         {
-            "name": "all-tests",
+            "name": "most-tests",
             "inherits": "basic-tests",
             "displayName": "Full development build",
-            "description": "Enables development build with examples and ALL tests",
+            "description": "Enables development build with extended set of tests (still relatively cheap to build)",
             "cacheVariables": {
                 "CATCH_BUILD_EXAMPLES": "ON",
                 "CATCH_BUILD_EXTRA_TESTS": "ON",
                 "CATCH_BUILD_SURROGATES": "ON",
+                "CATCH_BUILD_BENCHMARKS": "ON"
+            }
+        },
+        {
+            "name": "all-tests",
+            "inherits": "most-tests",
+            "displayName": "Full development build",
+            "description": "Enables development build with examples and ALL tests",
+            "cacheVariables": {
                 "CATCH_ENABLE_CONFIGURE_TESTS": "ON",
                 "CATCH_ENABLE_CMAKE_HELPER_TESTS": "ON"
             }

README.md

@@ -1,5 +1,16 @@
 <a id="top"></a>
-![Catch2 logo](data/artwork/catch2-logo-full-with-background.svg)
+
+<table width="100%">
+  <tr>
+    <td align="center" width="50%"><img src="/data/artwork/catch2-logo-full-with-background.svg" width="100%"></td>
+    <td align="center" width="50%">
+      <figure>
+        <figcaption>Special thanks to:</figcaption>
+        <a href="https://tuple.app/catch2"><img src="/data/sponsors/github_repo_sponsorship.png" width="100%"></a>
+      </figure>
+    </td>
+  </tr>
+</table>
 
 [![Github Releases](https://img.shields.io/github/release/catchorg/catch2.svg)](https://github.com/catchorg/catch2/releases)
 [![Linux build status](https://github.com/catchorg/Catch2/actions/workflows/linux-simple-builds.yml/badge.svg)](https://github.com/catchorg/Catch2/actions/workflows/linux-simple-builds.yml)

benchmarks/CMakeLists.txt

@@ -0,0 +1,16 @@
+include(CatchMiscFunctions)
+
+add_executable(AssertionsFastPath
+  runtime_assertion_benches.cpp
+)
+
+add_executable(AssertionsSlowPath
+  runtime_assertion_benches.cpp
+  assertion_listener.cpp
+)
+
+target_link_libraries(AssertionsFastPath PRIVATE Catch2::Catch2WithMain)
+target_link_libraries(AssertionsSlowPath PRIVATE Catch2::Catch2WithMain)
+
+list(APPEND CATCH_TEST_TARGETS AssertionsFastPath AssertionsSlowPath)
+set(CATCH_TEST_TARGETS ${CATCH_TEST_TARGETS} PARENT_SCOPE)

benchmarks/assertion_listener.cpp

@@ -0,0 +1,28 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/reporters/catch_reporter_event_listener.hpp>
+#include <catch2/reporters/catch_reporter_registrars.hpp>
+
+/**
+ * Event listener that listens to all assertions, forcing assertion slow path
+ */
+class AssertionSlowPathListener : public Catch::EventListenerBase {
+public:
+    static std::string getDescription() {
+        return "Validates ordering of Catch2's listener events";
+    }
+
+    AssertionSlowPathListener(Catch::IConfig const* config) :
+        EventListenerBase(config) {
+        m_preferences.shouldReportAllAssertions = true;
+        m_preferences.shouldReportAllAssertionStarts = true;
+    }
+};
+
+CATCH_REGISTER_LISTENER( AssertionSlowPathListener )

benchmarks/runtime_assertion_benches.cpp

@@ -0,0 +1,27 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/catch_test_macros.hpp>
+
+TEST_CASE("Simple REQUIRE - 10M") {
+    for (size_t i = 0; i < 10'000'000; ++i) {
+        REQUIRE(true);
+    }
+}
+
+TEST_CASE("Simple NOTHROW - 10M") {
+    for (size_t i = 0; i < 10'000'000; ++i) {
+        REQUIRE_NOTHROW([](){}());
+    }
+}
+
+TEST_CASE("Simple THROWS - 10M") {
+    for (size_t i = 0; i < 10'000'000; ++i) {
+        REQUIRE_THROWS([]() { throw 1; }());
+    }
+}

docs/ci-and-misc.md

@@ -66,17 +66,24 @@ test execution. Specifically it understands
  * JUnit output path via `XML_OUTPUT_FILE`
  * Test filtering via `TESTBRIDGE_TEST_ONLY`
  * Test sharding via `TEST_SHARD_INDEX`, `TEST_TOTAL_SHARDS`, and `TEST_SHARD_STATUS_FILE`
+ * Creating a file to signal premature test exit via `TEST_PREMATURE_EXIT_FILE`
+ * Setting the RNG seed via `TEST_RANDOM_SEED`
 
 > Support for `XML_OUTPUT_FILE` was [introduced](https://github.com/catchorg/Catch2/pull/2399) in Catch2 3.0.1
 
 > Support for `TESTBRIDGE_TEST_ONLY` and sharding was introduced in Catch2 3.2.0
 
+> Support for `TEST_PREMATURE_EXIT_FILE` and `TEST_RANDOM_SEED` was introduced in Catch2 3.11.0
+
 This integration is enabled via either a [compile time configuration
 option](configuration.md#bazel-support), or via `BAZEL_TEST` environment
 variable set to "1".
 
 > Support for `BAZEL_TEST` was [introduced](https://github.com/catchorg/Catch2/pull/2459) in Catch2 3.1.0
 
+Note that if both the Bazel environment var and command line option for
+something are used, the environment variable wins.
+
 
 ## Low-level tools
 

docs/command-line.md

@@ -32,6 +32,7 @@
 [Test Sharding](#test-sharding)<br>
 [Allow running the binary without tests](#allow-running-the-binary-without-tests)<br>
 [Output verbosity](#output-verbosity)<br>
+[Create file to guard against silent early termination](#create-file-to-guard-against-silent-early-termination)<br>
 
 Catch works quite nicely without any command line options at all - but for those times when you want greater control the following options are available.
 Click one of the following links to take you straight to that option - or scroll on to browse the available options.
@@ -649,6 +650,21 @@ ignored.
 Verbosity defaults to _normal_.
 
 
+## Create file to guard against silent early termination
+<pre>--premature-exit-guard-file &lt;path&gt;</pre>
+
+> Introduced in Catch2 3.11.0
+
+Tells Catch2 to create an empty file at specified path before the tests
+start, and delete it after the tests finish. If the file is present after
+the process stops, it can be assumed that the testing binary exited
+prematurely, e.g. due to the OOM killer.
+
+All directories in the path must already exist. If this option is used
+and Catch2 cannot create the file (e.g. the location is not writable),
+the test run will fail.
+
+
 ---
 
 [Home](Readme.md#top)

docs/release-notes.md

@@ -2,6 +2,7 @@
 
 # Release notes
 **Contents**<br>
+[3.11.0](#3110)<br>
 [3.10.0](#3100)<br>
 [3.9.1](#391)<br>
 [3.9.0](#390)<br>
@@ -70,6 +71,28 @@
 [Even Older versions](#even-older-versions)<br>
 
 
+## 3.11.0
+
+### Fixes
+* Fixed building on non-desktop GDK platforms (#3029)
+* Fixed message macros being susceptible to race in specific scenario (#3031)
+* Catch2's SEH filter will call the previously installed filter after reporting the error (#3033)
+
+### Improvements
+* Handling of scoped messages (e.g. `CAPTURE`) is a bit faster.
+* Better out-of-the-box support for QNX (#2953)
+* Improved performance of assertions by up-to 10%
+  * Release mode assertion fast-path sees the biggest improvement.
+* Faster processing of non-escaped strings in `--invisibles` mode.
+* Added support for Bazel's `TEST_RANDOM_SEED` env var (#3021)
+* Added support for Bazel's `TEST_PREMATURE_EXIT_FILE` env var (#3020)
+  * This creates a file that is deleted if the tests exit normally, but stays around if the process dies unexpectedly.
+  * This functionality is also exposed through CLI as `--premature-exit-guard-file`
+
+### Miscellaneous
+* **[Tuple.app](https://tuple.app/catch2) has sponsored Catch2**
+
+
 ## 3.10.0
 
 ### Fixes

extras/catch_amalgamated.cpp

@@ -6,8 +6,8 @@
 
 // SPDX-License-Identifier: BSL-1.0
 
-//  Catch v3.10.0
-//  Generated: 2025-08-24 16:18:04.775778
+//  Catch v3.11.0
+//  Generated: 2025-09-30 10:49:12.549018
 //  ----------------------------------------------------------
 //  This file is an amalgamation of multiple different files.
 //  You probably shouldn't edit it directly.
@@ -825,6 +825,8 @@ namespace Catch {
             m_data.reporterSpecifications.push_back( std::move( *parsed ) );
         }
 
+        // Reading bazel env vars can change some parts of the config data,
+        // so we have to process the bazel env before acting on the config.
         if ( enableBazelEnvSupport() ) {
             readBazelEnvVars();
         }
@@ -889,6 +891,8 @@ namespace Catch {
 
     bool Config::showHelp() const { return m_data.showHelp; }
 
+    std::string const& Config::getExitGuardFilePath() const { return m_data.prematureExitGuardFilePath; }
+
     // IConfig interface
     bool Config::allowThrows() const                   { return !m_data.noThrow; }
     StringRef Config::name() const { return m_data.name.empty() ? m_data.processName : m_data.name; }
@@ -950,6 +954,26 @@ namespace Catch {
                 m_data.shardCount = bazelShardOptions->shardCount;
             }
         }
+
+        const auto bazelExitGuardFile = Detail::getEnv( "TEST_PREMATURE_EXIT_FILE" );
+        if (bazelExitGuardFile) {
+            m_data.prematureExitGuardFilePath = bazelExitGuardFile;
+        }
+
+        const auto bazelRandomSeed = Detail::getEnv( "TEST_RANDOM_SEED" );
+        if ( bazelRandomSeed ) {
+            auto parsedSeed = parseUInt( bazelRandomSeed, 0 );
+            if ( !parsedSeed ) {
+                // Currently we handle issues with parsing other Bazel Env
+                // options by warning and ignoring the issue. So we do the
+                // same for random seed option.
+                Catch::cerr()
+                    << "Warning: could not parse 'TEST_RANDOM_SEED' ('"
+                    << bazelRandomSeed << "') as proper seed.\n";
+            } else {
+                m_data.rngSeed = *parsedSeed;
+            }
+        }
     }
 
 } // end namespace Catch
@@ -975,28 +999,26 @@ namespace Catch {
 
 
     ScopedMessage::ScopedMessage( MessageBuilder&& builder ):
-        m_info( CATCH_MOVE(builder.m_info) ) {
-        m_info.message = builder.m_stream.str();
-        getResultCapture().pushScopedMessage( m_info );
+        m_messageId( builder.m_info.sequence ) {
+        MessageInfo info( CATCH_MOVE( builder.m_info ) );
+        info.message = builder.m_stream.str();
+        IResultCapture::pushScopedMessage( CATCH_MOVE( info ) );
     }
 
     ScopedMessage::ScopedMessage( ScopedMessage&& old ) noexcept:
-        m_info( CATCH_MOVE( old.m_info ) ) {
+        m_messageId( old.m_messageId ) {
         old.m_moved = true;
     }
 
     ScopedMessage::~ScopedMessage() {
-        if ( !m_moved ){
-            getResultCapture().popScopedMessage(m_info);
-        }
+        if ( !m_moved ) { IResultCapture::popScopedMessage( m_messageId ); }
     }
 
 
     Capturer::Capturer( StringRef macroName,
                         SourceLineInfo const& lineInfo,
                         ResultWas::OfType resultType,
-                        StringRef names ):
-        m_resultCapture( getResultCapture() ) {
+                        StringRef names ) {
         auto trimmed = [&] (size_t start, size_t end) {
             while (names[start] == ',' || isspace(static_cast<unsigned char>(names[start]))) {
                 ++start;
@@ -1042,8 +1064,8 @@ namespace Catch {
             case ',':
                 if (start != pos && openings.empty()) {
                     m_messages.emplace_back(macroName, lineInfo, resultType);
-                    m_messages.back().message = static_cast<std::string>(trimmed(start, pos));
-                    m_messages.back().message += " := ";
+                    m_messages.back().message += trimmed(start, pos);
+                    m_messages.back().message += " := "_sr;
                     start = pos;
                 }
                 break;
@@ -1052,20 +1074,20 @@ namespace Catch {
         }
         assert(openings.empty() && "Mismatched openings");
         m_messages.emplace_back(macroName, lineInfo, resultType);
-        m_messages.back().message = static_cast<std::string>(trimmed(start, names.size() - 1));
-        m_messages.back().message += " := ";
+        m_messages.back().message += trimmed(start, names.size() - 1);
+        m_messages.back().message += " := "_sr;
     }
     Capturer::~Capturer() {
         assert( m_captured == m_messages.size() );
-        for ( size_t i = 0; i < m_captured; ++i ) {
-            m_resultCapture.popScopedMessage( m_messages[i] );
+        for (auto const& message : m_messages) {
+            IResultCapture::popScopedMessage( message.sequence );
         }
     }
 
     void Capturer::captureValue( size_t index, std::string const& value ) {
         assert( index < m_messages.size() );
         m_messages[index].message += value;
-        m_resultCapture.pushScopedMessage( m_messages[index] );
+        IResultCapture::pushScopedMessage( CATCH_MOVE( m_messages[index] ) );
         m_captured++;
     }
 
@@ -1149,7 +1171,6 @@ namespace Catch {
     }
     void cleanUp() {
         cleanupSingletons();
-        cleanUpContext();
     }
     std::string translateActiveException() {
         return getRegistryHub().getExceptionTranslatorRegistry().translateActiveException();
@@ -1161,6 +1182,8 @@ namespace Catch {
 
 
 #include <cassert>
+#include <cstdio>
+#include <cstdlib>
 #include <exception>
 #include <iomanip>
 #include <set>
@@ -1275,6 +1298,50 @@ namespace Catch {
             }
         }
 
+        // Creates empty file at path. The path must be writable, we do not
+        // try to create directories in path because that's hard in C++14.
+        void setUpGuardFile( std::string const& guardFilePath ) {
+            if ( !guardFilePath.empty() ) {
+#if defined( _MSC_VER )
+                std::FILE* file = nullptr;
+                if ( fopen_s( &file, guardFilePath.c_str(), "w" ) ) {
+                    char msgBuffer[100];
+                    const auto err = errno;
+                    std::string errMsg;
+                    if ( !strerror_s( msgBuffer, err ) ) {
+                        errMsg = msgBuffer;
+                    } else {
+                        errMsg = "Could not translate errno to a string";
+                    }
+
+#else
+                std::FILE* file = std::fopen( guardFilePath.c_str(), "w" );
+                if ( !file ) {
+                    const auto err = errno;
+                    const char* errMsg = std::strerror( err );
+#endif
+
+                    CATCH_RUNTIME_ERROR( "Could not open the exit guard file '"
+                                         << guardFilePath << "' because '"
+                                         << errMsg << "' (" << err << ')' );
+                }
+                const int ret = std::fclose( file );
+                CATCH_ENFORCE(
+                    ret == 0,
+                    "Error when closing the exit guard file: " << ret );
+            }
+        }
+
+        // Removes file at path. Assuming we created it in setUpGuardFile.
+        void tearDownGuardFile( std::string const& guardFilePath ) {
+            if ( !guardFilePath.empty() ) {
+                const int ret = std::remove( guardFilePath.c_str() );
+                CATCH_ENFORCE(
+                    ret == 0,
+                    "Error when removing the exit guard file: " << ret );
+            }
+        }
+
     } // anon namespace
 
     Session::Session() {
@@ -1393,6 +1460,7 @@ namespace Catch {
             static_cast<void>(std::getchar());
         }
         int exitCode = runInternal();
+
         if( ( m_configData.waitForKeypress & WaitForKeypress::BeforeExit ) != 0 ) {
             Catch::cout() << "...waiting for enter/ return before exiting, with code: " << exitCode << '\n' << std::flush;
             static_cast<void>(std::getchar());
@@ -1433,6 +1501,10 @@ namespace Catch {
         CATCH_TRY {
             config(); // Force config to be constructed
 
+            // We need to retrieve potential Bazel config with the full Config
+            // constructor, so we have to create the guard file after it is created.
+            setUpGuardFile( m_config->getExitGuardFilePath() );
+
             seedRng( *m_config );
 
             if (m_configData.filenamesAsTags) {
@@ -1462,9 +1534,12 @@ namespace Catch {
             TestGroup tests { CATCH_MOVE(reporter), m_config.get() };
             auto const totals = tests.execute();
 
+            // If we got here, running the tests finished normally-enough.
+            // They might've failed, but that would've been reported elsewhere.
+            tearDownGuardFile( m_config->getExitGuardFilePath() );
+
             if ( tests.hadUnmatchedTestSpecs()
                 && m_config->warnAboutUnmatchedTestSpecs() ) {
-                // UnmatchedTestSpecExitCode
                 return UnmatchedTestSpecExitCode;
             }
 
@@ -1974,35 +2049,35 @@ namespace Detail {
         std::string ret;
         // This is enough for the "don't escape invisibles" case, and a good
         // lower bound on the "escape invisibles" case.
-        ret.reserve(string.size() + 2);
+        ret.reserve( string.size() + 2 );
 
-        if (!escapeInvisibles) {
+        if ( !escapeInvisibles ) {
             ret += '"';
             ret += string;
             ret += '"';
             return ret;
         }
 
+        size_t last_start = 0;
+        auto write_to = [&]( size_t idx ) {
+            if ( last_start < idx ) {
+                ret += string.substr( last_start, idx - last_start );
+            }
+            last_start = idx + 1;
+        };
+
         ret += '"';
-        for (char c : string) {
-            switch (c) {
-            case '\r':
-                ret.append("\\r");
-                break;
-            case '\n':
-                ret.append("\\n");
-                break;
-            case '\t':
-                ret.append("\\t");
-                break;
-            case '\f':
-                ret.append("\\f");
-                break;
-            default:
-                ret.push_back(c);
-                break;
+        for ( size_t i = 0; i < string.size(); ++i ) {
+            const char c = string[i];
+            if ( c == '\r' || c == '\n' || c == '\t' || c == '\f' ) {
+                write_to( i );
+                if ( c == '\r' ) { ret.append( "\\r" ); }
+                if ( c == '\n' ) { ret.append( "\\n" ); }
+                if ( c == '\t' ) { ret.append( "\\t" ); }
+                if ( c == '\f' ) { ret.append( "\\f" ); }
             }
         }
+        write_to( string.size() );
         ret += '"';
 
         return ret;
@@ -2279,7 +2354,7 @@ namespace Catch {
     }
 
     Version const& libraryVersion() {
-        static Version version( 3, 10, 0, "", 0 );
+        static Version version( 3, 11, 0, "", 0 );
         return version;
     }
 
@@ -2367,8 +2442,14 @@ namespace Catch {
 
 
 namespace Catch {
+    namespace Detail {
+        void missingCaptureInstance() {
+            CATCH_INTERNAL_ERROR( "No result capture instance" );
+        }
+    } // namespace Detail
+
     IResultCapture::~IResultCapture() = default;
-}
+} // namespace Catch
 
 
 
@@ -3361,6 +3442,9 @@ namespace Catch {
             | Opt( config.allowZeroTests )
                 ["--allow-running-no-tests"]
                 ( "Treat 'No tests run' as a success" )
+            | Opt( config.prematureExitGuardFilePath, "path" )
+                ["--premature-exit-guard-file"]
+                ( "create a file before running tests and delete it during clean exit" )
             | Arg( config.testsOrTags, "test name|pattern|tags" )
                 ( "which test or tests to use" );
 
@@ -3515,7 +3599,11 @@ namespace {
 #endif // Windows/ ANSI/ None
 
 
-#if defined( CATCH_PLATFORM_LINUX ) || defined( CATCH_PLATFORM_MAC ) || defined( __GLIBC__ ) || defined(__FreeBSD__)
+#if defined( CATCH_PLATFORM_LINUX ) \
+ || defined( CATCH_PLATFORM_MAC ) \
+ || defined( __GLIBC__ ) \
+ || defined( __FreeBSD__ ) \
+ || defined( CATCH_PLATFORM_QNX )
 #    define CATCH_INTERNAL_HAS_ISATTY
 #    include <unistd.h>
 #endif
@@ -3639,20 +3727,10 @@ namespace Catch {
 
 namespace Catch {
 
-    Context* Context::currentContext = nullptr;
-
-    void cleanUpContext() {
-        delete Context::currentContext;
-        Context::currentContext = nullptr;
-    }
-    void Context::createContext() {
-        currentContext = new Context();
-    }
+    Context Context::currentContext;
 
     Context& getCurrentMutableContext() {
-        if ( !Context::currentContext ) { Context::createContext(); }
-        // NOLINTNEXTLINE(clang-analyzer-core.uninitialized.UndefReturn)
-        return *Context::currentContext;
+        return Context::currentContext;
     }
 
     SimplePcg32& sharedRng() {
@@ -3757,7 +3835,7 @@ namespace Catch {
         #endif
     } // namespace Catch
 
-#elif defined(CATCH_PLATFORM_LINUX)
+#elif defined(CATCH_PLATFORM_LINUX) || defined(CATCH_PLATFORM_QNX)
     #include <fstream>
     #include <string>
 
@@ -4091,23 +4169,27 @@ namespace Catch {
         { EXCEPTION_INT_DIVIDE_BY_ZERO, "Divide by zero error" },
     };
 
+    // Since we do not support multiple instantiations, we put these
+    // into global variables and rely on cleaning them up in outlined
+    // constructors/destructors
+    static LPTOP_LEVEL_EXCEPTION_FILTER previousTopLevelExceptionFilter = nullptr;
+
+
     static LONG CALLBACK topLevelExceptionFilter(PEXCEPTION_POINTERS ExceptionInfo) {
         for (auto const& def : signalDefs) {
             if (ExceptionInfo->ExceptionRecord->ExceptionCode == def.id) {
                 reportFatal(def.name);
             }
         }
-        // If its not an exception we care about, pass it along.
+        // If a filter was previously registered, invoke it
+        if (previousTopLevelExceptionFilter) {
+            return previousTopLevelExceptionFilter(ExceptionInfo);
+        }
+        // Otherwise, pass along all exceptions.
         // This stops us from eating debugger breaks etc.
         return EXCEPTION_CONTINUE_SEARCH;
     }
 
-    // Since we do not support multiple instantiations, we put these
-    // into global variables and rely on cleaning them up in outlined
-    // constructors/destructors
-    static LPTOP_LEVEL_EXCEPTION_FILTER previousTopLevelExceptionFilter = nullptr;
-
-
     // For MSVC, we reserve part of the stack memory for handling
     // memory overflow structured exception.
     FatalConditionHandler::FatalConditionHandler() {
@@ -5565,6 +5647,7 @@ ReporterSpec::ReporterSpec(
 
 #include <cstdio>
 #include <sstream>
+#include <tuple>
 #include <vector>
 
 namespace Catch {
@@ -5576,16 +5659,16 @@ namespace Catch {
         std::ostringstream m_referenceStream; // Used for copy state/ flags from
         Detail::Mutex m_mutex;
 
-        auto add() -> std::size_t {
+        auto add() -> std::pair<std::size_t, std::ostringstream*> {
             Detail::LockGuard _( m_mutex );
             if( m_unused.empty() ) {
                 m_streams.push_back( Detail::make_unique<std::ostringstream>() );
-                return m_streams.size()-1;
+                return { m_streams.size()-1, m_streams.back().get() };
             }
             else {
                 auto index = m_unused.back();
                 m_unused.pop_back();
-                return index;
+                return { index, m_streams[index].get() };
             }
         }
 
@@ -5599,10 +5682,10 @@ namespace Catch {
         }
     };
 
-    ReusableStringStream::ReusableStringStream()
-    :   m_index( Singleton<StringStreams>::getMutable().add() ),
-        m_oss( Singleton<StringStreams>::getMutable().m_streams[m_index].get() )
-    {}
+    ReusableStringStream::ReusableStringStream() {
+        std::tie( m_index, m_oss ) =
+            Singleton<StringStreams>::getMutable().add();
+    }
 
     ReusableStringStream::~ReusableStringStream() {
         static_cast<std::ostringstream*>( m_oss )->str("");
@@ -6085,28 +6168,6 @@ namespace Catch {
         m_reporter->benchmarkFailed( error );
     }
 
-    void RunContext::pushScopedMessage( MessageInfo const& message ) {
-        Detail::g_messages.push_back( message );
-    }
-
-    void RunContext::popScopedMessage( MessageInfo const& message ) {
-        // Note: On average, it would probably be better to look for the message
-        //       backwards. However, we do not expect to have to deal with more
-        //       messages than low single digits, so the optimization is tiny,
-        //       and we would have to hand-write the loop to avoid terrible
-        //       codegen of reverse iterators in debug mode.
-        Detail::g_messages.erase(
-            std::find_if( Detail::g_messages.begin(),
-                          Detail::g_messages.end(),
-                          [id = message.sequence]( MessageInfo const& msg ) {
-                              return msg.sequence == id;
-                          } ) );
-    }
-
-    void RunContext::emplaceUnscopedMessage( MessageBuilder&& builder ) {
-        Detail::g_messageScopes.emplace_back( CATCH_MOVE(builder) );
-    }
-
     std::string RunContext::getCurrentTestName() const {
         return m_activeTestCase
             ? m_activeTestCase->getTestCaseInfo().name
@@ -6433,11 +6494,26 @@ namespace Catch {
         }
     }
 
-    IResultCapture& getResultCapture() {
-        if (auto* capture = getCurrentContext().getResultCapture())
-            return *capture;
-        else
-            CATCH_INTERNAL_ERROR("No result capture instance");
+    void IResultCapture::pushScopedMessage( MessageInfo&& message ) {
+        Detail::g_messages.push_back( CATCH_MOVE( message ) );
+    }
+
+    void IResultCapture::popScopedMessage( unsigned int messageId ) {
+        // Note: On average, it would probably be better to look for the message
+        //       backwards. However, we do not expect to have to deal with more
+        //       messages than low single digits, so the optimization is tiny,
+        //       and we would have to hand-write the loop to avoid terrible
+        //       codegen of reverse iterators in debug mode.
+        Detail::g_messages.erase( std::find_if( Detail::g_messages.begin(),
+                                                Detail::g_messages.end(),
+                                                [=]( MessageInfo const& msg ) {
+                                                    return msg.sequence ==
+                                                           messageId;
+                                                } ) );
+    }
+
+    void IResultCapture::emplaceUnscopedMessage( MessageBuilder&& builder ) {
+        Detail::g_messageScopes.emplace_back( CATCH_MOVE( builder ) );
     }
 
     void seedRng(IConfig const& config) {

extras/catch_amalgamated.hpp

@@ -6,8 +6,8 @@
 
 // SPDX-License-Identifier: BSL-1.0
 
-//  Catch v3.10.0
-//  Generated: 2025-08-24 16:18:04.055916
+//  Catch v3.11.0
+//  Generated: 2025-09-30 10:49:11.225746
 //  ----------------------------------------------------------
 //  This file is an amalgamation of multiple different files.
 //  You probably shouldn't edit it directly.
@@ -101,6 +101,9 @@
 #elif defined(linux) || defined(__linux) || defined(__linux__)
 #  define CATCH_PLATFORM_LINUX
 
+#elif defined(__QNX__)
+#  define CATCH_PLATFORM_QNX
+
 #elif defined(WIN32) || defined(__WIN32__) || defined(_WIN32) || defined(_MSC_VER) || defined(__MINGW32__)
 #  define CATCH_PLATFORM_WINDOWS
 
@@ -308,13 +311,17 @@
 #    endif
 
 // Universal Windows platform does not support SEH
-// Or console colours (or console at all...)
-#  if defined(CATCH_PLATFORM_WINDOWS_UWP)
-#    define CATCH_INTERNAL_CONFIG_NO_COLOUR_WIN32
-#  else
+#  if !defined(CATCH_PLATFORM_WINDOWS_UWP)
 #    define CATCH_INTERNAL_CONFIG_WINDOWS_SEH
 #  endif
 
+// Only some Windows platform families support the console
+#  if defined(WINAPI_FAMILY_PARTITION)
+#    if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM)
+#      define CATCH_INTERNAL_CONFIG_NO_COLOUR_WIN32
+#    endif
+#  endif
+
 // MSVC traditional preprocessor needs some workaround for __VA_ARGS__
 // _MSVC_TRADITIONAL == 0 means new conformant preprocessor
 // _MSVC_TRADITIONAL == 1 means old traditional non-conformant preprocessor
@@ -564,11 +571,9 @@ namespace Catch {
         IConfig const* m_config = nullptr;
         IResultCapture* m_resultCapture = nullptr;
 
-        CATCH_EXPORT static Context* currentContext;
+        CATCH_EXPORT static Context currentContext;
         friend Context& getCurrentMutableContext();
         friend Context const& getCurrentContext();
-        static void createContext();
-        friend void cleanUpContext();
 
     public:
         constexpr IResultCapture* getResultCapture() const {
@@ -579,21 +584,14 @@ namespace Catch {
             m_resultCapture = resultCapture;
         }
         constexpr void setConfig( IConfig const* config ) { m_config = config; }
-
     };
 
     Context& getCurrentMutableContext();
 
     inline Context const& getCurrentContext() {
-        // We duplicate the logic from `getCurrentMutableContext` here,
-        // to avoid paying the call overhead in debug mode.
-        if ( !Context::currentContext ) { Context::createContext(); }
-        // NOLINTNEXTLINE(clang-analyzer-core.uninitialized.UndefReturn)
-        return *Context::currentContext;
+        return Context::currentContext;
     }
 
-    void cleanUpContext();
-
     class SimplePcg32;
     SimplePcg32& sharedRng();
 }
@@ -1069,10 +1067,9 @@ namespace Catch {
         virtual void benchmarkEnded( BenchmarkStats<> const& stats ) = 0;
         virtual void benchmarkFailed( StringRef error ) = 0;
 
-        virtual void pushScopedMessage( MessageInfo const& message ) = 0;
-        virtual void popScopedMessage( MessageInfo const& message ) = 0;
-
-        virtual void emplaceUnscopedMessage( MessageBuilder&& builder ) = 0;
+        static void pushScopedMessage( MessageInfo&& message );
+        static void popScopedMessage( unsigned int messageId );
+        static void emplaceUnscopedMessage( MessageBuilder&& builder );
 
         virtual void handleFatalErrorCondition( StringRef message ) = 0;
 
@@ -1108,7 +1105,18 @@ namespace Catch {
         virtual void exceptionEarlyReported() = 0;
     };
 
-    IResultCapture& getResultCapture();
+    namespace Detail {
+        [[noreturn]]
+        void missingCaptureInstance();
+    }
+    inline IResultCapture& getResultCapture() {
+        if (auto* capture = getCurrentContext().getResultCapture()) {
+            return *capture;
+        } else {
+            Detail::missingCaptureInstance();
+        }
+    }
+
 }
 
 #endif // CATCH_INTERFACES_CAPTURE_HPP_INCLUDED
@@ -3800,6 +3808,8 @@ namespace Catch {
 
         std::vector<std::string> testsOrTags;
         std::vector<std::string> sectionsToRun;
+
+        std::string prematureExitGuardFilePath;
     };
 
 
@@ -3827,6 +3837,8 @@ namespace Catch {
 
         bool showHelp() const;
 
+        std::string const& getExitGuardFilePath() const;
+
         // IConfig interface
         bool allowThrows() const override;
         StringRef name() const override;
@@ -3961,6 +3973,7 @@ namespace Catch {
         std::string message;
         SourceLineInfo lineInfo;
         ResultWas::OfType type;
+        // The "ID" of the message, used to know when to remove it from reporter context.
         unsigned int sequence;
 
         DEPRECATED( "Explicitly use the 'sequence' member instead" )
@@ -4020,13 +4033,12 @@ namespace Catch {
         ScopedMessage( ScopedMessage&& old ) noexcept;
         ~ScopedMessage();
 
-        MessageInfo m_info;
+        unsigned int m_messageId;
         bool m_moved = false;
     };
 
     class Capturer {
         std::vector<MessageInfo> m_messages;
-        IResultCapture& m_resultCapture;
         size_t m_captured = 0;
     public:
         Capturer( StringRef macroName, SourceLineInfo const& lineInfo, ResultWas::OfType resultType, StringRef names );
@@ -4074,7 +4086,7 @@ namespace Catch {
 
 ///////////////////////////////////////////////////////////////////////////////
 #define INTERNAL_CATCH_UNSCOPED_INFO( macroName, log ) \
-    Catch::getResultCapture().emplaceUnscopedMessage( Catch::MessageBuilder( macroName##_catch_sr, CATCH_INTERNAL_LINEINFO, Catch::ResultWas::Info ) << log )
+    Catch::IResultCapture::emplaceUnscopedMessage( Catch::MessageBuilder( macroName##_catch_sr, CATCH_INTERNAL_LINEINFO, Catch::ResultWas::Info ) << log )
 
 
 #if defined(CATCH_CONFIG_PREFIX_MESSAGES) && !defined(CATCH_CONFIG_DISABLE)
@@ -7466,7 +7478,7 @@ namespace Catch {
 #define CATCH_VERSION_MACROS_HPP_INCLUDED
 
 #define CATCH_VERSION_MAJOR 3
-#define CATCH_VERSION_MINOR 10
+#define CATCH_VERSION_MINOR 11
 #define CATCH_VERSION_PATCH 0
 
 #endif // CATCH_VERSION_MACROS_HPP_INCLUDED
@@ -7882,8 +7894,9 @@ namespace Generators {
     class FilterGenerator final : public IGenerator<T> {
         GeneratorWrapper<T> m_generator;
         Predicate m_predicate;
+        static_assert(!std::is_reference<Predicate>::value, "This would most likely result in a dangling reference");
     public:
-        template <typename P = Predicate>
+        template <typename P>
         FilterGenerator(P&& pred, GeneratorWrapper<T>&& generator):
             m_generator(CATCH_MOVE(generator)),
             m_predicate(CATCH_FORWARD(pred))
@@ -7915,7 +7928,7 @@ namespace Generators {
 
     template <typename T, typename Predicate>
     GeneratorWrapper<T> filter(Predicate&& pred, GeneratorWrapper<T>&& generator) {
-        return GeneratorWrapper<T>(Catch::Detail::make_unique<FilterGenerator<T, Predicate>>(CATCH_FORWARD(pred), CATCH_MOVE(generator)));
+        return GeneratorWrapper<T>(Catch::Detail::make_unique<FilterGenerator<T, typename std::remove_reference<Predicate>::type>>(CATCH_FORWARD(pred), CATCH_MOVE(generator)));
     }
 
     template <typename T>
@@ -9555,7 +9568,7 @@ namespace Catch {
         #define CATCH_TRAP()  __asm__(".inst 0xde01")
     #endif
 
-#elif defined(CATCH_PLATFORM_LINUX)
+#elif defined(CATCH_PLATFORM_LINUX) || defined(CATCH_PLATFORM_QNX)
     // If we can use inline assembler, do it because this allows us to break
     // directly at the location of the failing check instead of breaking inside
     // raise() called from it, i.e. one stack frame below.
@@ -10718,11 +10731,6 @@ namespace Catch {
         void benchmarkEnded( BenchmarkStats<> const& stats ) override;
         void benchmarkFailed( StringRef error ) override;
 
-        void pushScopedMessage( MessageInfo const& message ) override;
-        void popScopedMessage( MessageInfo const& message ) override;
-
-        void emplaceUnscopedMessage( MessageBuilder&& builder ) override;
-
         std::string getCurrentTestName() const override;
 
         const AssertionResult* getLastResult() const override;

meson.build

@@ -8,7 +8,7 @@
 project(
   'catch2',
   'cpp',
-  version: '3.10.0', # CML version placeholder, don't delete
+  version: '3.11.0', # CML version placeholder, don't delete
   license: 'BSL-1.0',
   meson_version: '>=0.54.1',
 )

src/CMakeLists.txt

@@ -98,6 +98,7 @@ set(IMPL_HEADERS
   ${SOURCES_DIR}/internal/catch_jsonwriter.hpp
   ${SOURCES_DIR}/internal/catch_lazy_expr.hpp
   ${SOURCES_DIR}/internal/catch_leak_detector.hpp
+  ${SOURCES_DIR}/internal/catch_lifetimebound.hpp
   ${SOURCES_DIR}/internal/catch_list.hpp
   ${SOURCES_DIR}/internal/catch_logical_traits.hpp
   ${SOURCES_DIR}/internal/catch_message_info.hpp

src/catch2/catch_all.hpp

@@ -79,6 +79,7 @@
 #include <catch2/internal/catch_jsonwriter.hpp>
 #include <catch2/internal/catch_lazy_expr.hpp>
 #include <catch2/internal/catch_leak_detector.hpp>
+#include <catch2/internal/catch_lifetimebound.hpp>
 #include <catch2/internal/catch_list.hpp>
 #include <catch2/internal/catch_logical_traits.hpp>
 #include <catch2/internal/catch_message_info.hpp>

src/catch2/catch_config.cpp

@@ -119,6 +119,8 @@ namespace Catch {
             m_data.reporterSpecifications.push_back( std::move( *parsed ) );
         }
 
+        // Reading bazel env vars can change some parts of the config data,
+        // so we have to process the bazel env before acting on the config.
         if ( enableBazelEnvSupport() ) {
             readBazelEnvVars();
         }
@@ -183,6 +185,8 @@ namespace Catch {
 
     bool Config::showHelp() const { return m_data.showHelp; }
 
+    std::string const& Config::getExitGuardFilePath() const { return m_data.prematureExitGuardFilePath; }
+
     // IConfig interface
     bool Config::allowThrows() const                   { return !m_data.noThrow; }
     StringRef Config::name() const { return m_data.name.empty() ? m_data.processName : m_data.name; }
@@ -244,6 +248,26 @@ namespace Catch {
                 m_data.shardCount = bazelShardOptions->shardCount;
             }
         }
+
+        const auto bazelExitGuardFile = Detail::getEnv( "TEST_PREMATURE_EXIT_FILE" );
+        if (bazelExitGuardFile) {
+            m_data.prematureExitGuardFilePath = bazelExitGuardFile;
+        }
+
+        const auto bazelRandomSeed = Detail::getEnv( "TEST_RANDOM_SEED" );
+        if ( bazelRandomSeed ) {
+            auto parsedSeed = parseUInt( bazelRandomSeed, 0 );
+            if ( !parsedSeed ) {
+                // Currently we handle issues with parsing other Bazel Env
+                // options by warning and ignoring the issue. So we do the
+                // same for random seed option.
+                Catch::cerr()
+                    << "Warning: could not parse 'TEST_RANDOM_SEED' ('"
+                    << bazelRandomSeed << "') as proper seed.\n";
+            } else {
+                m_data.rngSeed = *parsedSeed;
+            }
+        }
     }
 
 } // end namespace Catch

src/catch2/catch_config.hpp

@@ -87,6 +87,8 @@ namespace Catch {
 
         std::vector<std::string> testsOrTags;
         std::vector<std::string> sectionsToRun;
+
+        std::string prematureExitGuardFilePath;
     };
 
 
@@ -114,6 +116,8 @@ namespace Catch {
 
         bool showHelp() const;
 
+        std::string const& getExitGuardFilePath() const;
+
         // IConfig interface
         bool allowThrows() const override;
         StringRef name() const override;

src/catch2/catch_message.cpp

@@ -19,28 +19,26 @@ namespace Catch {
 
 
     ScopedMessage::ScopedMessage( MessageBuilder&& builder ):
-        m_info( CATCH_MOVE(builder.m_info) ) {
-        m_info.message = builder.m_stream.str();
-        getResultCapture().pushScopedMessage( m_info );
+        m_messageId( builder.m_info.sequence ) {
+        MessageInfo info( CATCH_MOVE( builder.m_info ) );
+        info.message = builder.m_stream.str();
+        IResultCapture::pushScopedMessage( CATCH_MOVE( info ) );
     }
 
     ScopedMessage::ScopedMessage( ScopedMessage&& old ) noexcept:
-        m_info( CATCH_MOVE( old.m_info ) ) {
+        m_messageId( old.m_messageId ) {
         old.m_moved = true;
     }
 
     ScopedMessage::~ScopedMessage() {
-        if ( !m_moved ){
-            getResultCapture().popScopedMessage(m_info);
-        }
+        if ( !m_moved ) { IResultCapture::popScopedMessage( m_messageId ); }
     }
 
 
     Capturer::Capturer( StringRef macroName,
                         SourceLineInfo const& lineInfo,
                         ResultWas::OfType resultType,
-                        StringRef names ):
-        m_resultCapture( getResultCapture() ) {
+                        StringRef names ) {
         auto trimmed = [&] (size_t start, size_t end) {
             while (names[start] == ',' || isspace(static_cast<unsigned char>(names[start]))) {
                 ++start;
@@ -86,8 +84,8 @@ namespace Catch {
             case ',':
                 if (start != pos && openings.empty()) {
                     m_messages.emplace_back(macroName, lineInfo, resultType);
-                    m_messages.back().message = static_cast<std::string>(trimmed(start, pos));
-                    m_messages.back().message += " := ";
+                    m_messages.back().message += trimmed(start, pos);
+                    m_messages.back().message += " := "_sr;
                     start = pos;
                 }
                 break;
@@ -96,20 +94,20 @@ namespace Catch {
         }
         assert(openings.empty() && "Mismatched openings");
         m_messages.emplace_back(macroName, lineInfo, resultType);
-        m_messages.back().message = static_cast<std::string>(trimmed(start, names.size() - 1));
-        m_messages.back().message += " := ";
+        m_messages.back().message += trimmed(start, names.size() - 1);
+        m_messages.back().message += " := "_sr;
     }
     Capturer::~Capturer() {
         assert( m_captured == m_messages.size() );
-        for ( size_t i = 0; i < m_captured; ++i ) {
-            m_resultCapture.popScopedMessage( m_messages[i] );
+        for (auto const& message : m_messages) {
+            IResultCapture::popScopedMessage( message.sequence );
         }
     }
 
     void Capturer::captureValue( size_t index, std::string const& value ) {
         assert( index < m_messages.size() );
         m_messages[index].message += value;
-        m_resultCapture.pushScopedMessage( m_messages[index] );
+        IResultCapture::pushScopedMessage( CATCH_MOVE( m_messages[index] ) );
         m_captured++;
     }
 

src/catch2/catch_message.hpp

@@ -57,13 +57,12 @@ namespace Catch {
         ScopedMessage( ScopedMessage&& old ) noexcept;
         ~ScopedMessage();
 
-        MessageInfo m_info;
+        unsigned int m_messageId;
         bool m_moved = false;
     };
 
     class Capturer {
         std::vector<MessageInfo> m_messages;
-        IResultCapture& m_resultCapture;
         size_t m_captured = 0;
     public:
         Capturer( StringRef macroName, SourceLineInfo const& lineInfo, ResultWas::OfType resultType, StringRef names );
@@ -111,7 +110,7 @@ namespace Catch {
 
 ///////////////////////////////////////////////////////////////////////////////
 #define INTERNAL_CATCH_UNSCOPED_INFO( macroName, log ) \
-    Catch::getResultCapture().emplaceUnscopedMessage( Catch::MessageBuilder( macroName##_catch_sr, CATCH_INTERNAL_LINEINFO, Catch::ResultWas::Info ) << log )
+    Catch::IResultCapture::emplaceUnscopedMessage( Catch::MessageBuilder( macroName##_catch_sr, CATCH_INTERNAL_LINEINFO, Catch::ResultWas::Info ) << log )
 
 
 #if defined(CATCH_CONFIG_PREFIX_MESSAGES) && !defined(CATCH_CONFIG_DISABLE)

src/catch2/catch_registry_hub.cpp

@@ -96,7 +96,6 @@ namespace Catch {
     }
     void cleanUp() {
         cleanupSingletons();
-        cleanUpContext();
     }
     std::string translateActiveException() {
         return getRegistryHub().getExceptionTranslatorRegistry().translateActiveException();

src/catch2/catch_session.cpp

@@ -26,6 +26,8 @@
 #include <catch2/internal/catch_istream.hpp>
 
 #include <cassert>
+#include <cstdio>
+#include <cstdlib>
 #include <exception>
 #include <iomanip>
 #include <set>
@@ -140,6 +142,50 @@ namespace Catch {
             }
         }
 
+        // Creates empty file at path. The path must be writable, we do not
+        // try to create directories in path because that's hard in C++14.
+        void setUpGuardFile( std::string const& guardFilePath ) {
+            if ( !guardFilePath.empty() ) {
+#if defined( _MSC_VER )
+                std::FILE* file = nullptr;
+                if ( fopen_s( &file, guardFilePath.c_str(), "w" ) ) {
+                    char msgBuffer[100];
+                    const auto err = errno;
+                    std::string errMsg;
+                    if ( !strerror_s( msgBuffer, err ) ) {
+                        errMsg = msgBuffer;
+                    } else {
+                        errMsg = "Could not translate errno to a string";
+                    }
+
+#else
+                std::FILE* file = std::fopen( guardFilePath.c_str(), "w" );
+                if ( !file ) {
+                    const auto err = errno;
+                    const char* errMsg = std::strerror( err );
+#endif
+
+                    CATCH_RUNTIME_ERROR( "Could not open the exit guard file '"
+                                         << guardFilePath << "' because '"
+                                         << errMsg << "' (" << err << ')' );
+                }
+                const int ret = std::fclose( file );
+                CATCH_ENFORCE(
+                    ret == 0,
+                    "Error when closing the exit guard file: " << ret );
+            }
+        }
+
+        // Removes file at path. Assuming we created it in setUpGuardFile.
+        void tearDownGuardFile( std::string const& guardFilePath ) {
+            if ( !guardFilePath.empty() ) {
+                const int ret = std::remove( guardFilePath.c_str() );
+                CATCH_ENFORCE(
+                    ret == 0,
+                    "Error when removing the exit guard file: " << ret );
+            }
+        }
+
     } // anon namespace
 
     Session::Session() {
@@ -258,6 +304,7 @@ namespace Catch {
             static_cast<void>(std::getchar());
         }
         int exitCode = runInternal();
+
         if( ( m_configData.waitForKeypress & WaitForKeypress::BeforeExit ) != 0 ) {
             Catch::cout() << "...waiting for enter/ return before exiting, with code: " << exitCode << '\n' << std::flush;
             static_cast<void>(std::getchar());
@@ -298,6 +345,10 @@ namespace Catch {
         CATCH_TRY {
             config(); // Force config to be constructed
 
+            // We need to retrieve potential Bazel config with the full Config
+            // constructor, so we have to create the guard file after it is created.
+            setUpGuardFile( m_config->getExitGuardFilePath() );
+
             seedRng( *m_config );
 
             if (m_configData.filenamesAsTags) {
@@ -327,9 +378,12 @@ namespace Catch {
             TestGroup tests { CATCH_MOVE(reporter), m_config.get() };
             auto const totals = tests.execute();
 
+            // If we got here, running the tests finished normally-enough.
+            // They might've failed, but that would've been reported elsewhere.
+            tearDownGuardFile( m_config->getExitGuardFilePath() );
+
             if ( tests.hadUnmatchedTestSpecs()
                 && m_config->warnAboutUnmatchedTestSpecs() ) {
-                // UnmatchedTestSpecExitCode
                 return UnmatchedTestSpecExitCode;
             }
 

src/catch2/catch_tostring.cpp

@@ -61,35 +61,35 @@ namespace Detail {
         std::string ret;
         // This is enough for the "don't escape invisibles" case, and a good
         // lower bound on the "escape invisibles" case.
-        ret.reserve(string.size() + 2);
+        ret.reserve( string.size() + 2 );
 
-        if (!escapeInvisibles) {
+        if ( !escapeInvisibles ) {
             ret += '"';
             ret += string;
             ret += '"';
             return ret;
         }
 
+        size_t last_start = 0;
+        auto write_to = [&]( size_t idx ) {
+            if ( last_start < idx ) {
+                ret += string.substr( last_start, idx - last_start );
+            }
+            last_start = idx + 1;
+        };
+
         ret += '"';
-        for (char c : string) {
-            switch (c) {
-            case '\r':
-                ret.append("\\r");
-                break;
-            case '\n':
-                ret.append("\\n");
-                break;
-            case '\t':
-                ret.append("\\t");
-                break;
-            case '\f':
-                ret.append("\\f");
-                break;
-            default:
-                ret.push_back(c);
-                break;
+        for ( size_t i = 0; i < string.size(); ++i ) {
+            const char c = string[i];
+            if ( c == '\r' || c == '\n' || c == '\t' || c == '\f' ) {
+                write_to( i );
+                if ( c == '\r' ) { ret.append( "\\r" ); }
+                if ( c == '\n' ) { ret.append( "\\n" ); }
+                if ( c == '\t' ) { ret.append( "\\t" ); }
+                if ( c == '\f' ) { ret.append( "\\f" ); }
             }
         }
+        write_to( string.size() );
         ret += '"';
 
         return ret;

src/catch2/catch_version.cpp

@@ -36,7 +36,7 @@ namespace Catch {
     }
 
     Version const& libraryVersion() {
-        static Version version( 3, 10, 0, "", 0 );
+        static Version version( 3, 11, 0, "", 0 );
         return version;
     }
 

src/catch2/catch_version_macros.hpp

@@ -9,7 +9,7 @@
 #define CATCH_VERSION_MACROS_HPP_INCLUDED
 
 #define CATCH_VERSION_MAJOR 3
-#define CATCH_VERSION_MINOR 10
+#define CATCH_VERSION_MINOR 11
 #define CATCH_VERSION_PATCH 0
 
 #endif // CATCH_VERSION_MACROS_HPP_INCLUDED

src/catch2/interfaces/catch_interfaces_capture.cpp

@@ -7,7 +7,14 @@
 // SPDX-License-Identifier: BSL-1.0
 
 #include <catch2/interfaces/catch_interfaces_capture.hpp>
+#include <catch2/internal/catch_enforce.hpp>
 
 namespace Catch {
+    namespace Detail {
+        void missingCaptureInstance() {
+            CATCH_INTERNAL_ERROR( "No result capture instance" );
+        }
+    } // namespace Detail
+
     IResultCapture::~IResultCapture() = default;
-}
+} // namespace Catch

src/catch2/interfaces/catch_interfaces_capture.hpp

@@ -10,6 +10,7 @@
 
 #include <string>
 
+#include <catch2/internal/catch_context.hpp>
 #include <catch2/internal/catch_stringref.hpp>
 #include <catch2/internal/catch_result_type.hpp>
 #include <catch2/internal/catch_unique_ptr.hpp>
@@ -62,10 +63,9 @@ namespace Catch {
         virtual void benchmarkEnded( BenchmarkStats<> const& stats ) = 0;
         virtual void benchmarkFailed( StringRef error ) = 0;
 
-        virtual void pushScopedMessage( MessageInfo const& message ) = 0;
-        virtual void popScopedMessage( MessageInfo const& message ) = 0;
-
-        virtual void emplaceUnscopedMessage( MessageBuilder&& builder ) = 0;
+        static void pushScopedMessage( MessageInfo&& message );
+        static void popScopedMessage( unsigned int messageId );
+        static void emplaceUnscopedMessage( MessageBuilder&& builder );
 
         virtual void handleFatalErrorCondition( StringRef message ) = 0;
 
@@ -101,7 +101,18 @@ namespace Catch {
         virtual void exceptionEarlyReported() = 0;
     };
 
-    IResultCapture& getResultCapture();
+    namespace Detail {
+        [[noreturn]]
+        void missingCaptureInstance();
+    }
+    inline IResultCapture& getResultCapture() {
+        if (auto* capture = getCurrentContext().getResultCapture()) {
+            return *capture;
+        } else {
+            Detail::missingCaptureInstance();
+        }
+    }
+
 }
 
 #endif // CATCH_INTERFACES_CAPTURE_HPP_INCLUDED

src/catch2/internal/catch_commandline.cpp

@@ -305,6 +305,9 @@ namespace Catch {
             | Opt( config.allowZeroTests )
                 ["--allow-running-no-tests"]
                 ( "Treat 'No tests run' as a success" )
+            | Opt( config.prematureExitGuardFilePath, "path" )
+                ["--premature-exit-guard-file"]
+                ( "create a file before running tests and delete it during clean exit" )
             | Arg( config.testsOrTags, "test name|pattern|tags" )
                 ( "which test or tests to use" );
 

src/catch2/internal/catch_compiler_capabilities.hpp

@@ -220,13 +220,17 @@
 #    endif
 
 // Universal Windows platform does not support SEH
-// Or console colours (or console at all...)
-#  if defined(CATCH_PLATFORM_WINDOWS_UWP)
-#    define CATCH_INTERNAL_CONFIG_NO_COLOUR_WIN32
-#  else
+#  if !defined(CATCH_PLATFORM_WINDOWS_UWP)
 #    define CATCH_INTERNAL_CONFIG_WINDOWS_SEH
 #  endif
 
+// Only some Windows platform families support the console
+#  if defined(WINAPI_FAMILY_PARTITION)
+#    if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM)
+#      define CATCH_INTERNAL_CONFIG_NO_COLOUR_WIN32
+#    endif
+#  endif
+
 // MSVC traditional preprocessor needs some workaround for __VA_ARGS__
 // _MSVC_TRADITIONAL == 0 means new conformant preprocessor
 // _MSVC_TRADITIONAL == 1 means old traditional non-conformant preprocessor

src/catch2/internal/catch_console_colour.cpp

@@ -161,7 +161,11 @@ namespace {
 #endif // Windows/ ANSI/ None
 
 
-#if defined( CATCH_PLATFORM_LINUX ) || defined( CATCH_PLATFORM_MAC ) || defined( __GLIBC__ ) || defined(__FreeBSD__)
+#if defined( CATCH_PLATFORM_LINUX ) \
+ || defined( CATCH_PLATFORM_MAC ) \
+ || defined( __GLIBC__ ) \
+ || defined( __FreeBSD__ ) \
+ || defined( CATCH_PLATFORM_QNX )
 #    define CATCH_INTERNAL_HAS_ISATTY
 #    include <unistd.h>
 #endif

src/catch2/internal/catch_context.cpp

@@ -6,25 +6,14 @@
 
 // SPDX-License-Identifier: BSL-1.0
 #include <catch2/internal/catch_context.hpp>
-#include <catch2/internal/catch_noncopyable.hpp>
 #include <catch2/internal/catch_random_number_generator.hpp>
 
 namespace Catch {
 
-    Context* Context::currentContext = nullptr;
-
-    void cleanUpContext() {
-        delete Context::currentContext;
-        Context::currentContext = nullptr;
-    }
-    void Context::createContext() {
-        currentContext = new Context();
-    }
+    Context Context::currentContext;
 
     Context& getCurrentMutableContext() {
-        if ( !Context::currentContext ) { Context::createContext(); }
-        // NOLINTNEXTLINE(clang-analyzer-core.uninitialized.UndefReturn)
-        return *Context::currentContext;
+        return Context::currentContext;
     }
 
     SimplePcg32& sharedRng() {

src/catch2/internal/catch_context.hpp

@@ -19,11 +19,9 @@ namespace Catch {
         IConfig const* m_config = nullptr;
         IResultCapture* m_resultCapture = nullptr;
 
-        CATCH_EXPORT static Context* currentContext;
+        CATCH_EXPORT static Context currentContext;
         friend Context& getCurrentMutableContext();
         friend Context const& getCurrentContext();
-        static void createContext();
-        friend void cleanUpContext();
 
     public:
         constexpr IResultCapture* getResultCapture() const {
@@ -34,21 +32,14 @@ namespace Catch {
             m_resultCapture = resultCapture;
         }
         constexpr void setConfig( IConfig const* config ) { m_config = config; }
-
     };
 
     Context& getCurrentMutableContext();
 
     inline Context const& getCurrentContext() {
-        // We duplicate the logic from `getCurrentMutableContext` here,
-        // to avoid paying the call overhead in debug mode.
-        if ( !Context::currentContext ) { Context::createContext(); }
-        // NOLINTNEXTLINE(clang-analyzer-core.uninitialized.UndefReturn)
-        return *Context::currentContext;
+        return Context::currentContext;
     }
 
-    void cleanUpContext();
-
     class SimplePcg32;
     SimplePcg32& sharedRng();
 }

src/catch2/internal/catch_debugger.cpp

@@ -69,7 +69,7 @@
         #endif
     } // namespace Catch
 
-#elif defined(CATCH_PLATFORM_LINUX)
+#elif defined(CATCH_PLATFORM_LINUX) || defined(CATCH_PLATFORM_QNX)
     #include <fstream>
     #include <string>
 

src/catch2/internal/catch_debugger.hpp

@@ -49,7 +49,7 @@ namespace Catch {
         #define CATCH_TRAP()  __asm__(".inst 0xde01")
     #endif
 
-#elif defined(CATCH_PLATFORM_LINUX)
+#elif defined(CATCH_PLATFORM_LINUX) || defined(CATCH_PLATFORM_QNX)
     // If we can use inline assembler, do it because this allows us to break
     // directly at the location of the failing check instead of breaking inside
     // raise() called from it, i.e. one stack frame below.

src/catch2/internal/catch_fatal_condition_handler.cpp

@@ -86,23 +86,27 @@ namespace Catch {
         { EXCEPTION_INT_DIVIDE_BY_ZERO, "Divide by zero error" },
     };
 
+    // Since we do not support multiple instantiations, we put these
+    // into global variables and rely on cleaning them up in outlined
+    // constructors/destructors
+    static LPTOP_LEVEL_EXCEPTION_FILTER previousTopLevelExceptionFilter = nullptr;
+
+
     static LONG CALLBACK topLevelExceptionFilter(PEXCEPTION_POINTERS ExceptionInfo) {
         for (auto const& def : signalDefs) {
             if (ExceptionInfo->ExceptionRecord->ExceptionCode == def.id) {
                 reportFatal(def.name);
             }
         }
-        // If its not an exception we care about, pass it along.
+        // If a filter was previously registered, invoke it
+        if (previousTopLevelExceptionFilter) {
+            return previousTopLevelExceptionFilter(ExceptionInfo);
+        }
+        // Otherwise, pass along all exceptions.
         // This stops us from eating debugger breaks etc.
         return EXCEPTION_CONTINUE_SEARCH;
     }
 
-    // Since we do not support multiple instantiations, we put these
-    // into global variables and rely on cleaning them up in outlined
-    // constructors/destructors
-    static LPTOP_LEVEL_EXCEPTION_FILTER previousTopLevelExceptionFilter = nullptr;
-
-
     // For MSVC, we reserve part of the stack memory for handling
     // memory overflow structured exception.
     FatalConditionHandler::FatalConditionHandler() {

src/catch2/internal/catch_lifetimebound.hpp

@@ -0,0 +1,24 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#ifndef CATCH_LIFETIMEBOUND_HPP_INCLUDED
+#define CATCH_LIFETIMEBOUND_HPP_INCLUDED
+
+#if !defined( __has_cpp_attribute )
+#    define CATCH_ATTR_LIFETIMEBOUND
+#elif __has_cpp_attribute( msvc::lifetimebound )
+#    define CATCH_ATTR_LIFETIMEBOUND [[msvc::lifetimebound]]
+#elif __has_cpp_attribute( clang::lifetimebound )
+#    define CATCH_ATTR_LIFETIMEBOUND [[clang::lifetimebound]]
+#elif __has_cpp_attribute( lifetimebound )
+#    define CATCH_ATTR_LIFETIMEBOUND [[lifetimebound]]
+#else
+#    define CATCH_ATTR_LIFETIMEBOUND
+#endif
+
+#endif // CATCH_LIFETIMEBOUND_HPP_INCLUDED

src/catch2/internal/catch_message_info.hpp

@@ -26,6 +26,7 @@ namespace Catch {
         std::string message;
         SourceLineInfo lineInfo;
         ResultWas::OfType type;
+        // The "ID" of the message, used to know when to remove it from reporter context.
         unsigned int sequence;
 
         DEPRECATED( "Explicitly use the 'sequence' member instead" )

src/catch2/internal/catch_platform.hpp

@@ -25,6 +25,9 @@
 #elif defined(linux) || defined(__linux) || defined(__linux__)
 #  define CATCH_PLATFORM_LINUX
 
+#elif defined(__QNX__)
+#  define CATCH_PLATFORM_QNX
+
 #elif defined(WIN32) || defined(__WIN32__) || defined(_WIN32) || defined(_MSC_VER) || defined(__MINGW32__)
 #  define CATCH_PLATFORM_WINDOWS
 

src/catch2/internal/catch_reusable_string_stream.cpp

@@ -12,6 +12,7 @@
 
 #include <cstdio>
 #include <sstream>
+#include <tuple>
 #include <vector>
 
 namespace Catch {
@@ -23,16 +24,16 @@ namespace Catch {
         std::ostringstream m_referenceStream; // Used for copy state/ flags from
         Detail::Mutex m_mutex;
 
-        auto add() -> std::size_t {
+        auto add() -> std::pair<std::size_t, std::ostringstream*> {
             Detail::LockGuard _( m_mutex );
             if( m_unused.empty() ) {
                 m_streams.push_back( Detail::make_unique<std::ostringstream>() );
-                return m_streams.size()-1;
+                return { m_streams.size()-1, m_streams.back().get() };
             }
             else {
                 auto index = m_unused.back();
                 m_unused.pop_back();
-                return index;
+                return { index, m_streams[index].get() };
             }
         }
 
@@ -46,10 +47,10 @@ namespace Catch {
         }
     };
 
-    ReusableStringStream::ReusableStringStream()
-    :   m_index( Singleton<StringStreams>::getMutable().add() ),
-        m_oss( Singleton<StringStreams>::getMutable().m_streams[m_index].get() )
-    {}
+    ReusableStringStream::ReusableStringStream() {
+        std::tie( m_index, m_oss ) =
+            Singleton<StringStreams>::getMutable().add();
+    }
 
     ReusableStringStream::~ReusableStringStream() {
         static_cast<std::ostringstream*>( m_oss )->str("");

src/catch2/internal/catch_run_context.cpp

@@ -483,28 +483,6 @@ namespace Catch {
         m_reporter->benchmarkFailed( error );
     }
 
-    void RunContext::pushScopedMessage( MessageInfo const& message ) {
-        Detail::g_messages.push_back( message );
-    }
-
-    void RunContext::popScopedMessage( MessageInfo const& message ) {
-        // Note: On average, it would probably be better to look for the message
-        //       backwards. However, we do not expect to have to deal with more
-        //       messages than low single digits, so the optimization is tiny,
-        //       and we would have to hand-write the loop to avoid terrible
-        //       codegen of reverse iterators in debug mode.
-        Detail::g_messages.erase(
-            std::find_if( Detail::g_messages.begin(),
-                          Detail::g_messages.end(),
-                          [id = message.sequence]( MessageInfo const& msg ) {
-                              return msg.sequence == id;
-                          } ) );
-    }
-
-    void RunContext::emplaceUnscopedMessage( MessageBuilder&& builder ) {
-        Detail::g_messageScopes.emplace_back( CATCH_MOVE(builder) );
-    }
-
     std::string RunContext::getCurrentTestName() const {
         return m_activeTestCase
             ? m_activeTestCase->getTestCaseInfo().name
@@ -831,11 +809,26 @@ namespace Catch {
         }
     }
 
-    IResultCapture& getResultCapture() {
-        if (auto* capture = getCurrentContext().getResultCapture())
-            return *capture;
-        else
-            CATCH_INTERNAL_ERROR("No result capture instance");
+    void IResultCapture::pushScopedMessage( MessageInfo&& message ) {
+        Detail::g_messages.push_back( CATCH_MOVE( message ) );
+    }
+
+    void IResultCapture::popScopedMessage( unsigned int messageId ) {
+        // Note: On average, it would probably be better to look for the message
+        //       backwards. However, we do not expect to have to deal with more
+        //       messages than low single digits, so the optimization is tiny,
+        //       and we would have to hand-write the loop to avoid terrible
+        //       codegen of reverse iterators in debug mode.
+        Detail::g_messages.erase( std::find_if( Detail::g_messages.begin(),
+                                                Detail::g_messages.end(),
+                                                [=]( MessageInfo const& msg ) {
+                                                    return msg.sequence ==
+                                                           messageId;
+                                                } ) );
+    }
+
+    void IResultCapture::emplaceUnscopedMessage( MessageBuilder&& builder ) {
+        Detail::g_messageScopes.emplace_back( CATCH_MOVE( builder ) );
     }
 
     void seedRng(IConfig const& config) {

src/catch2/internal/catch_run_context.hpp

@@ -94,11 +94,6 @@ namespace Catch {
         void benchmarkEnded( BenchmarkStats<> const& stats ) override;
         void benchmarkFailed( StringRef error ) override;
 
-        void pushScopedMessage( MessageInfo const& message ) override;
-        void popScopedMessage( MessageInfo const& message ) override;
-
-        void emplaceUnscopedMessage( MessageBuilder&& builder ) override;
-
         std::string getCurrentTestName() const override;
 
         const AssertionResult* getLastResult() const override;

src/catch2/internal/catch_string_manip.hpp

@@ -8,6 +8,7 @@
 #ifndef CATCH_STRING_MANIP_HPP_INCLUDED
 #define CATCH_STRING_MANIP_HPP_INCLUDED
 
+#include <catch2/internal/catch_lifetimebound.hpp>
 #include <catch2/internal/catch_stringref.hpp>
 
 #include <cstdint>
@@ -28,10 +29,10 @@ namespace Catch {
     //! Returns a new string without whitespace at the start/end
     std::string trim( std::string const& str );
     //! Returns a substring of the original ref without whitespace. Beware lifetimes!
-    StringRef trim(StringRef ref);
+    StringRef trim( StringRef ref CATCH_ATTR_LIFETIMEBOUND );
 
     // !!! Be aware, returns refs into original string - make sure original string outlives them
-    std::vector<StringRef> splitStringRef( StringRef str, char delimiter );
+    std::vector<StringRef> splitStringRef( StringRef str CATCH_ATTR_LIFETIMEBOUND, char delimiter );
     bool replaceInPlace( std::string& str, std::string const& replaceThis, std::string const& withThis );
 
     /**
@@ -49,7 +50,7 @@ namespace Catch {
         StringRef m_label;
 
     public:
-        constexpr pluralise(std::uint64_t count, StringRef label):
+        constexpr pluralise(std::uint64_t count, StringRef label CATCH_ATTR_LIFETIMEBOUND):
             m_count(count),
             m_label(label)
         {}

src/catch2/internal/catch_stringref.hpp

@@ -8,11 +8,12 @@
 #ifndef CATCH_STRINGREF_HPP_INCLUDED
 #define CATCH_STRINGREF_HPP_INCLUDED
 
+#include <catch2/internal/catch_lifetimebound.hpp>
+
 #include <cstddef>
 #include <string>
 #include <iosfwd>
 #include <cassert>
-
 #include <cstring>
 
 namespace Catch {
@@ -36,14 +37,16 @@ namespace Catch {
     public: // construction
         constexpr StringRef() noexcept = default;
 
-        StringRef( char const* rawChars ) noexcept;
+        StringRef( char const* rawChars CATCH_ATTR_LIFETIMEBOUND ) noexcept;
 
-        constexpr StringRef( char const* rawChars, size_type size ) noexcept
+        constexpr StringRef( char const* rawChars CATCH_ATTR_LIFETIMEBOUND,
+                             size_type size ) noexcept
         :   m_start( rawChars ),
             m_size( size )
         {}
 
-        StringRef( std::string const& stdString ) noexcept
+        StringRef(
+            std::string const& stdString CATCH_ATTR_LIFETIMEBOUND ) noexcept
         :   m_start( stdString.c_str() ),
             m_size( stdString.size() )
         {}
@@ -89,7 +92,7 @@ namespace Catch {
         }
 
         // Returns the current start pointer. May not be null-terminated.
-        constexpr char const* data() const noexcept {
+        constexpr char const* data() const noexcept CATCH_ATTR_LIFETIMEBOUND {
             return m_start;
         }
 

src/catch2/internal/catch_test_case_tracker.hpp

@@ -8,6 +8,7 @@
 #ifndef CATCH_TEST_CASE_TRACKER_HPP_INCLUDED
 #define CATCH_TEST_CASE_TRACKER_HPP_INCLUDED
 
+#include <catch2/internal/catch_lifetimebound.hpp>
 #include <catch2/internal/catch_source_line_info.hpp>
 #include <catch2/internal/catch_unique_ptr.hpp>
 #include <catch2/internal/catch_stringref.hpp>
@@ -48,7 +49,7 @@ namespace TestCaseTracking {
         StringRef name;
         SourceLineInfo location;
 
-        constexpr NameAndLocationRef( StringRef name_,
+        constexpr NameAndLocationRef( StringRef name_ CATCH_ATTR_LIFETIMEBOUND,
                                       SourceLineInfo location_ ):
             name( name_ ), location( location_ ) {}
 

src/catch2/matchers/catch_matchers.hpp

@@ -10,6 +10,7 @@
 
 #include <catch2/matchers/internal/catch_matchers_impl.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
+#include <catch2/internal/catch_lifetimebound.hpp>
 
 #include <string>
 #include <vector>
@@ -79,11 +80,15 @@ namespace Matchers {
                 return description;
             }
 
-            friend MatchAllOf operator&& (MatchAllOf&& lhs, MatcherBase<ArgT> const& rhs) {
+            friend MatchAllOf operator&&( MatchAllOf&& lhs,
+                                          MatcherBase<ArgT> const& rhs
+                                              CATCH_ATTR_LIFETIMEBOUND ) {
                 lhs.m_matchers.push_back(&rhs);
                 return CATCH_MOVE(lhs);
             }
-            friend MatchAllOf operator&& (MatcherBase<ArgT> const& lhs, MatchAllOf&& rhs) {
+            friend MatchAllOf
+            operator&&( MatcherBase<ArgT> const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                        MatchAllOf&& rhs ) {
                 rhs.m_matchers.insert(rhs.m_matchers.begin(), &lhs);
                 return CATCH_MOVE(rhs);
             }
@@ -131,11 +136,15 @@ namespace Matchers {
                 return description;
             }
 
-            friend MatchAnyOf operator|| (MatchAnyOf&& lhs, MatcherBase<ArgT> const& rhs) {
+            friend MatchAnyOf operator||( MatchAnyOf&& lhs,
+                                          MatcherBase<ArgT> const& rhs
+                                              CATCH_ATTR_LIFETIMEBOUND ) {
                 lhs.m_matchers.push_back(&rhs);
                 return CATCH_MOVE(lhs);
             }
-            friend MatchAnyOf operator|| (MatcherBase<ArgT> const& lhs, MatchAnyOf&& rhs) {
+            friend MatchAnyOf
+            operator||( MatcherBase<ArgT> const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                        MatchAnyOf&& rhs ) {
                 rhs.m_matchers.insert(rhs.m_matchers.begin(), &lhs);
                 return CATCH_MOVE(rhs);
             }
@@ -155,7 +164,8 @@ namespace Matchers {
             MatcherBase<ArgT> const& m_underlyingMatcher;
 
         public:
-            explicit MatchNotOf( MatcherBase<ArgT> const& underlyingMatcher ):
+            explicit MatchNotOf( MatcherBase<ArgT> const& underlyingMatcher
+                                     CATCH_ATTR_LIFETIMEBOUND ):
                 m_underlyingMatcher( underlyingMatcher )
             {}
 
@@ -171,16 +181,22 @@ namespace Matchers {
     } // namespace Detail
 
     template <typename T>
-    Detail::MatchAllOf<T> operator&& (MatcherBase<T> const& lhs, MatcherBase<T> const& rhs) {
+    Detail::MatchAllOf<T>
+    operator&&( MatcherBase<T> const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherBase<T> const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return Detail::MatchAllOf<T>{} && lhs && rhs;
     }
+
     template <typename T>
-    Detail::MatchAnyOf<T> operator|| (MatcherBase<T> const& lhs, MatcherBase<T> const& rhs) {
+    Detail::MatchAnyOf<T>
+    operator||( MatcherBase<T> const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherBase<T> const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return Detail::MatchAnyOf<T>{} || lhs || rhs;
     }
 
     template <typename T>
-    Detail::MatchNotOf<T> operator! (MatcherBase<T> const& matcher) {
+    Detail::MatchNotOf<T>
+    operator!( MatcherBase<T> const& matcher CATCH_ATTR_LIFETIMEBOUND ) {
         return Detail::MatchNotOf<T>{ matcher };
     }
 

src/catch2/matchers/catch_matchers_templated.hpp

@@ -11,6 +11,7 @@
 #include <catch2/matchers/catch_matchers.hpp>
 #include <catch2/internal/catch_stringref.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
+#include <catch2/internal/catch_lifetimebound.hpp>
 #include <catch2/internal/catch_logical_traits.hpp>
 
 #include <array>
@@ -114,7 +115,8 @@ namespace Matchers {
             MatchAllOfGeneric(MatchAllOfGeneric&&) = default;
             MatchAllOfGeneric& operator=(MatchAllOfGeneric&&) = default;
 
-            MatchAllOfGeneric(MatcherTs const&... matchers) : m_matchers{ {std::addressof(matchers)...} } {}
+            MatchAllOfGeneric(MatcherTs const&... matchers CATCH_ATTR_LIFETIMEBOUND)
+                : m_matchers{ {std::addressof(matchers)...} } {}
             explicit MatchAllOfGeneric(std::array<void const*, sizeof...(MatcherTs)> matchers) : m_matchers{matchers} {}
 
             template<typename Arg>
@@ -136,8 +138,8 @@ namespace Matchers {
             template<typename... MatchersRHS>
             friend
             MatchAllOfGeneric<MatcherTs..., MatchersRHS...> operator && (
-                    MatchAllOfGeneric<MatcherTs...>&& lhs,
-                    MatchAllOfGeneric<MatchersRHS...>&& rhs) {
+                MatchAllOfGeneric<MatcherTs...>&& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatchAllOfGeneric<MatchersRHS...>&& rhs CATCH_ATTR_LIFETIMEBOUND ) {
                 return MatchAllOfGeneric<MatcherTs..., MatchersRHS...>{array_cat(CATCH_MOVE(lhs.m_matchers), CATCH_MOVE(rhs.m_matchers))};
             }
 
@@ -145,8 +147,8 @@ namespace Matchers {
             template<typename MatcherRHS>
             friend std::enable_if_t<is_matcher_v<MatcherRHS>,
             MatchAllOfGeneric<MatcherTs..., MatcherRHS>> operator && (
-                    MatchAllOfGeneric<MatcherTs...>&& lhs,
-                    MatcherRHS const& rhs) {
+                MatchAllOfGeneric<MatcherTs...>&& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherRHS const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
                 return MatchAllOfGeneric<MatcherTs..., MatcherRHS>{array_cat(CATCH_MOVE(lhs.m_matchers), static_cast<void const*>(&rhs))};
             }
 
@@ -154,8 +156,8 @@ namespace Matchers {
             template<typename MatcherLHS>
             friend std::enable_if_t<is_matcher_v<MatcherLHS>,
             MatchAllOfGeneric<MatcherLHS, MatcherTs...>> operator && (
-                    MatcherLHS const& lhs,
-                    MatchAllOfGeneric<MatcherTs...>&& rhs) {
+                MatcherLHS const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatchAllOfGeneric<MatcherTs...>&& rhs CATCH_ATTR_LIFETIMEBOUND ) {
                 return MatchAllOfGeneric<MatcherLHS, MatcherTs...>{array_cat(static_cast<void const*>(std::addressof(lhs)), CATCH_MOVE(rhs.m_matchers))};
             }
         };
@@ -169,7 +171,8 @@ namespace Matchers {
             MatchAnyOfGeneric(MatchAnyOfGeneric&&) = default;
             MatchAnyOfGeneric& operator=(MatchAnyOfGeneric&&) = default;
 
-            MatchAnyOfGeneric(MatcherTs const&... matchers) : m_matchers{ {std::addressof(matchers)...} } {}
+            MatchAnyOfGeneric(MatcherTs const&... matchers CATCH_ATTR_LIFETIMEBOUND)
+                : m_matchers{ {std::addressof(matchers)...} } {}
             explicit MatchAnyOfGeneric(std::array<void const*, sizeof...(MatcherTs)> matchers) : m_matchers{matchers} {}
 
             template<typename Arg>
@@ -190,8 +193,8 @@ namespace Matchers {
             //! Avoids type nesting for `GenericAnyOf || GenericAnyOf` case
             template<typename... MatchersRHS>
             friend MatchAnyOfGeneric<MatcherTs..., MatchersRHS...> operator || (
-                    MatchAnyOfGeneric<MatcherTs...>&& lhs,
-                    MatchAnyOfGeneric<MatchersRHS...>&& rhs) {
+                MatchAnyOfGeneric<MatcherTs...>&& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatchAnyOfGeneric<MatchersRHS...>&& rhs CATCH_ATTR_LIFETIMEBOUND ) {
                 return MatchAnyOfGeneric<MatcherTs..., MatchersRHS...>{array_cat(CATCH_MOVE(lhs.m_matchers), CATCH_MOVE(rhs.m_matchers))};
             }
 
@@ -199,8 +202,8 @@ namespace Matchers {
             template<typename MatcherRHS>
             friend std::enable_if_t<is_matcher_v<MatcherRHS>,
             MatchAnyOfGeneric<MatcherTs..., MatcherRHS>> operator || (
-                    MatchAnyOfGeneric<MatcherTs...>&& lhs,
-                    MatcherRHS const& rhs) {
+                    MatchAnyOfGeneric<MatcherTs...>&& lhs CATCH_ATTR_LIFETIMEBOUND,
+                    MatcherRHS const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
                 return MatchAnyOfGeneric<MatcherTs..., MatcherRHS>{array_cat(CATCH_MOVE(lhs.m_matchers), static_cast<void const*>(std::addressof(rhs)))};
             }
 
@@ -208,8 +211,8 @@ namespace Matchers {
             template<typename MatcherLHS>
             friend std::enable_if_t<is_matcher_v<MatcherLHS>,
             MatchAnyOfGeneric<MatcherLHS, MatcherTs...>> operator || (
-                MatcherLHS const& lhs,
-                MatchAnyOfGeneric<MatcherTs...>&& rhs) {
+                MatcherLHS const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatchAnyOfGeneric<MatcherTs...>&& rhs CATCH_ATTR_LIFETIMEBOUND) {
                 return MatchAnyOfGeneric<MatcherLHS, MatcherTs...>{array_cat(static_cast<void const*>(std::addressof(lhs)), CATCH_MOVE(rhs.m_matchers))};
             }
         };
@@ -225,7 +228,8 @@ namespace Matchers {
             MatchNotOfGeneric(MatchNotOfGeneric&&) = default;
             MatchNotOfGeneric& operator=(MatchNotOfGeneric&&) = default;
 
-            explicit MatchNotOfGeneric(MatcherT const& matcher) : m_matcher{matcher} {}
+            explicit MatchNotOfGeneric(MatcherT const& matcher CATCH_ATTR_LIFETIMEBOUND)
+                : m_matcher{matcher} {}
 
             template<typename Arg>
             bool match(Arg&& arg) const {
@@ -237,7 +241,9 @@ namespace Matchers {
             }
 
             //! Negating negation can just unwrap and return underlying matcher
-            friend MatcherT const& operator ! (MatchNotOfGeneric<MatcherT> const& matcher) {
+            friend MatcherT const&
+            operator!( MatchNotOfGeneric<MatcherT> const& matcher
+                           CATCH_ATTR_LIFETIMEBOUND ) {
                 return matcher.m_matcher;
             }
         };
@@ -247,20 +253,22 @@ namespace Matchers {
     // compose only generic matchers
     template<typename MatcherLHS, typename MatcherRHS>
     std::enable_if_t<Detail::are_generic_matchers_v<MatcherLHS, MatcherRHS>, Detail::MatchAllOfGeneric<MatcherLHS, MatcherRHS>>
-        operator && (MatcherLHS const& lhs, MatcherRHS const& rhs) {
+    operator&&( MatcherLHS const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherRHS const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return { lhs, rhs };
     }
 
     template<typename MatcherLHS, typename MatcherRHS>
     std::enable_if_t<Detail::are_generic_matchers_v<MatcherLHS, MatcherRHS>, Detail::MatchAnyOfGeneric<MatcherLHS, MatcherRHS>>
-        operator || (MatcherLHS const& lhs, MatcherRHS const& rhs) {
+    operator||( MatcherLHS const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherRHS const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return { lhs, rhs };
     }
 
     //! Wrap provided generic matcher in generic negator
     template<typename MatcherT>
     std::enable_if_t<Detail::is_generic_matcher_v<MatcherT>, Detail::MatchNotOfGeneric<MatcherT>>
-        operator ! (MatcherT const& matcher) {
+    operator!( MatcherT const& matcher CATCH_ATTR_LIFETIMEBOUND ) {
         return Detail::MatchNotOfGeneric<MatcherT>{matcher};
     }
 
@@ -268,25 +276,29 @@ namespace Matchers {
     // compose mixed generic and non-generic matchers
     template<typename MatcherLHS, typename ArgRHS>
     std::enable_if_t<Detail::is_generic_matcher_v<MatcherLHS>, Detail::MatchAllOfGeneric<MatcherLHS, MatcherBase<ArgRHS>>>
-        operator && (MatcherLHS const& lhs, MatcherBase<ArgRHS> const& rhs) {
+    operator&&( MatcherLHS const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherBase<ArgRHS> const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return { lhs, rhs };
     }
 
     template<typename ArgLHS, typename MatcherRHS>
     std::enable_if_t<Detail::is_generic_matcher_v<MatcherRHS>, Detail::MatchAllOfGeneric<MatcherBase<ArgLHS>, MatcherRHS>>
-        operator && (MatcherBase<ArgLHS> const& lhs, MatcherRHS const& rhs) {
+    operator&&( MatcherBase<ArgLHS> const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherRHS const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return { lhs, rhs };
     }
 
     template<typename MatcherLHS, typename ArgRHS>
     std::enable_if_t<Detail::is_generic_matcher_v<MatcherLHS>, Detail::MatchAnyOfGeneric<MatcherLHS, MatcherBase<ArgRHS>>>
-        operator || (MatcherLHS const& lhs, MatcherBase<ArgRHS> const& rhs) {
+    operator||( MatcherLHS const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherBase<ArgRHS> const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return { lhs, rhs };
     }
 
     template<typename ArgLHS, typename MatcherRHS>
     std::enable_if_t<Detail::is_generic_matcher_v<MatcherRHS>, Detail::MatchAnyOfGeneric<MatcherBase<ArgLHS>, MatcherRHS>>
-        operator || (MatcherBase<ArgLHS> const& lhs, MatcherRHS const& rhs) {
+    operator||( MatcherBase<ArgLHS> const& lhs CATCH_ATTR_LIFETIMEBOUND,
+                MatcherRHS const& rhs CATCH_ATTR_LIFETIMEBOUND ) {
         return { lhs, rhs };
     }
 

src/catch2/meson.build

@@ -105,6 +105,7 @@ internal_headers = [
   'internal/catch_jsonwriter.hpp',
   'internal/catch_lazy_expr.hpp',
   'internal/catch_leak_detector.hpp',
+  'internal/catch_lifetimebound.hpp',
   'internal/catch_list.hpp',
   'internal/catch_logical_traits.hpp',
   'internal/catch_message_info.hpp',

tests/CMakeLists.txt

@@ -662,5 +662,38 @@ foreach(reporterName # "Automake" - the simple .trs format does not support any
   )
 endforeach()
 
+add_test(NAME "Bazel::RngSeedEnvVar::JustEnv"
+  COMMAND
+    $<TARGET_FILE:SelfTest> "Factorials are computed"
+)
+set_tests_properties("Bazel::RngSeedEnvVar::JustEnv"
+  PROPERTIES
+    ENVIRONMENT "BAZEL_TEST=1;TEST_RANDOM_SEED=18181818"
+    PASS_REGULAR_EXPRESSION "Randomness seeded to: 18181818"
+)
+
+add_test(NAME "Bazel::RngSeedEnvVar::EnvHasPriorityOverCLI"
+  COMMAND
+    $<TARGET_FILE:SelfTest> "Factorials are computed"
+    --rng-seed 17171717
+)
+set_tests_properties("Bazel::RngSeedEnvVar::EnvHasPriorityOverCLI"
+  PROPERTIES
+    ENVIRONMENT "BAZEL_TEST=1;TEST_RANDOM_SEED=18181818"
+    PASS_REGULAR_EXPRESSION "Randomness seeded to: 18181818"
+)
+
+add_test(NAME "Bazel::RngSeedEnvVar::MalformedValueIsIgnored"
+  COMMAND
+    $<TARGET_FILE:SelfTest> "Factorials are computed"
+    --rng-seed 17171717
+)
+set_tests_properties("Bazel::RngSeedEnvVar::MalformedValueIsIgnored"
+  PROPERTIES
+    ENVIRONMENT "BAZEL_TEST=1;TEST_RANDOM_SEED=XOXOXOXO"
+    PASS_REGULAR_EXPRESSION "Randomness seeded to: 17171717"
+)
+
+
 list(APPEND CATCH_TEST_TARGETS SelfTest)
 set(CATCH_TEST_TARGETS ${CATCH_TEST_TARGETS} PARENT_SCOPE)

tests/ExtraTests/CMakeLists.txt

@@ -95,7 +95,7 @@ foreach(target DisabledExceptions-DefaultHandler DisabledExceptions-CustomHandle
   target_compile_options(${target}
     PUBLIC
       $<$<CXX_COMPILER_ID:MSVC>:/EHs-c-;/D_HAS_EXCEPTIONS=0>
-      $<$<OR:$<CXX_COMPILER_ID:Clang>,$<CXX_COMPILER_ID:GNU>,$<CXX_COMPILER_ID:AppleClang>>:-fno-exceptions>
+      $<$<OR:$<CXX_COMPILER_ID:Clang>,$<CXX_COMPILER_ID:GNU>,$<CXX_COMPILER_ID:QCC>,$<CXX_COMPILER_ID:AppleClang>>:-fno-exceptions>
   )
   target_link_libraries(${target} Catch2_buildall_interface)
 endforeach()
@@ -109,18 +109,6 @@ set_tests_properties(CATCH_CONFIG_DISABLE_EXCEPTIONS-1
     FAIL_REGULAR_EXPRESSION "abort;terminate;fatal"
 )
 
-add_executable(BazelReporter ${TESTS_DIR}/X30-BazelReporter.cpp)
-target_compile_definitions(BazelReporter PRIVATE CATCH_CONFIG_BAZEL_SUPPORT)
-target_link_libraries(BazelReporter Catch2_buildall_interface)
-add_test(NAME CATCH_CONFIG_BAZEL_REPORTER-1
-  COMMAND
-  Python3::Interpreter "${CATCH_DIR}/tests/TestScripts/testBazelReporter.py" $<TARGET_FILE:BazelReporter> "${CMAKE_CURRENT_BINARY_DIR}"
-)
-set_tests_properties(CATCH_CONFIG_BAZEL_REPORTER-1
-  PROPERTIES
-    LABELS "uses-python"
-)
-
 # We must now test this works without the build flag.
 add_executable(BazelReporterNoCatchConfig ${TESTS_DIR}/X30-BazelReporter.cpp)
 target_link_libraries(BazelReporterNoCatchConfig Catch2WithMain)
@@ -429,6 +417,50 @@ set_tests_properties(Reporters::CrashInJunitReporter
     LABELS "uses-signals"
 )
 
+
+add_executable(QuickExitInTest ${TESTS_DIR}/X40-QuickExit.cpp)
+target_link_libraries(QuickExitInTest PRIVATE Catch2::Catch2WithMain)
+add_test(
+  NAME BazelEnv::TEST_PREMATURE_EXIT_FILE
+  COMMAND
+    Python3::Interpreter
+    "${CATCH_DIR}/tests/TestScripts/testBazelExitGuardFile.py"
+    $<TARGET_FILE:QuickExitInTest>
+    "${CMAKE_CURRENT_BINARY_DIR}"
+    "bazel"
+)
+set_tests_properties(BazelEnv::TEST_PREMATURE_EXIT_FILE
+  PROPERTIES
+    LABELS "uses-python"
+)
+add_test(
+  NAME PrematureExitGuardFileCanBeUsedFromCLI::CheckAfterCrash
+  COMMAND
+    Python3::Interpreter
+    "${CATCH_DIR}/tests/TestScripts/testBazelExitGuardFile.py"
+    $<TARGET_FILE:QuickExitInTest>
+    "${CMAKE_CURRENT_BINARY_DIR}"
+    "cli"
+)
+set_tests_properties(PrematureExitGuardFileCanBeUsedFromCLI::CheckAfterCrash
+  PROPERTIES
+    LABELS "uses-python"
+)
+add_test(
+  NAME PrematureExitGuardFileCanBeUsedFromCLI::CheckWithoutCrash
+  COMMAND
+    Python3::Interpreter
+    "${CATCH_DIR}/tests/TestScripts/testBazelExitGuardFile.py"
+    $<TARGET_FILE:QuickExitInTest>
+    "${CMAKE_CURRENT_BINARY_DIR}"
+    "no-crash"
+)
+set_tests_properties(PrematureExitGuardFileCanBeUsedFromCLI::CheckWithoutCrash
+  PROPERTIES
+    LABELS "uses-python"
+)
+
+
 add_executable(AssertionStartingEventGoesBeforeAssertionIsEvaluated
   X20-AssertionStartingEventGoesBeforeAssertionIsEvaluated.cpp
 )

tests/ExtraTests/X40-QuickExit.cpp

@@ -0,0 +1,28 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+/**\file
+ * Call ~~quick_exit~~ inside a test.
+ *
+ * This is used to test whether Catch2 properly creates the crash guard
+ * file based on provided arguments.
+ */
+
+#include <catch2/catch_test_macros.hpp>
+
+#include <cstdlib>
+
+TEST_CASE("quick_exit", "[quick_exit]") {
+    // Return 0 as fake "successful" exit, while there should be a guard
+    // file created and kept.
+    std::exit(0);
+    // We cannot use quick_exit because libstdc++ on older MacOS versions didn't support it yet.
+    // std::quick_exit(0);
+}
+
+TEST_CASE("pass") {}

tests/SelfTest/IntrospectiveTests/ToString.tests.cpp

@@ -6,11 +6,13 @@
 
 // SPDX-License-Identifier: BSL-1.0
 
+#include <catch2/benchmark/catch_benchmark.hpp>
+#include <catch2/catch_template_test_macros.hpp>
+#include <catch2/catch_test_macros.hpp>
+#include <catch2/generators/catch_generators.hpp>
 #include <catch2/internal/catch_enum_values_registry.hpp>
 #include <catch2/matchers/catch_matchers_string.hpp>
 #include <catch2/matchers/catch_matchers_vector.hpp>
-#include <catch2/catch_test_macros.hpp>
-#include <catch2/catch_template_test_macros.hpp>
 
 #include <chrono>
 
@@ -139,3 +141,26 @@ TEST_CASE( "Exception thrown inside stringify does not fail the test", "[toStrin
     ThrowsOnStringification tos;
     CHECK( tos == tos );
 }
+
+TEST_CASE( "string escaping benchmark", "[toString][!benchmark]" ) {
+    const auto input_length = GENERATE( as<size_t>{}, 10, 100, 10'000, 100'000 );
+    std::string test_input( input_length, 'a' );
+    BENCHMARK( "no-escape string, no-escaping, len=" +
+               std::to_string( input_length ) ) {
+        return Catch::Detail::convertIntoString( test_input, false );
+    };
+    BENCHMARK( "no-escape string, escaping, len=" +
+               std::to_string( input_length ) ) {
+        return Catch::Detail::convertIntoString( test_input, true );
+    };
+
+    std::string escape_input( input_length, '\r' );
+    BENCHMARK( "full escape string, no-escaping, len=" +
+               std::to_string( input_length ) ) {
+        return Catch::Detail::convertIntoString( escape_input, false );
+    };
+    BENCHMARK( "full escape string, escaping, len=" +
+               std::to_string( input_length ) ) {
+        return Catch::Detail::convertIntoString( escape_input, true );
+    };
+}

tests/TestScripts/testBazelExitGuardFile.py

@@ -0,0 +1,88 @@
+#!/usr/bin/env python3
+
+#              Copyright Catch2 Authors
+# Distributed under the Boost Software License, Version 1.0.
+#   (See accompanying file LICENSE.txt or copy at
+#        https://www.boost.org/LICENSE_1_0.txt)
+
+# SPDX-License-Identifier: BSL-1.0
+
+import os
+import sys
+import subprocess
+
+def generate_path_suffix() -> str:
+    return os.urandom(16).hex()[:16]
+
+
+def run_common(cmd, env = None):
+    cmd_env = env if env is not None else os.environ.copy()
+    print('Running:', cmd)
+
+    try:
+        ret = subprocess.run(
+            cmd,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            check=True,
+            universal_newlines=True,
+            env=cmd_env
+        )
+    except subprocess.SubprocessError as ex:
+        print('Could not run "{}"'.format(cmd))
+        print("Return code: {}".format(ex.returncode))
+        print("stdout: {}".format(ex.stdout))
+        print("stderr: {}".format(ex.stderr))
+        raise
+
+
+def test_bazel_env_vars(bin_path, guard_path):
+    env = os.environ.copy()
+    env["TEST_PREMATURE_EXIT_FILE"] = guard_path
+    env["BAZEL_TEST"] = '1'
+    run_common([bin_path], env)
+
+def test_cli_parameter(bin_path, guard_path):
+    cmd = [
+      bin_path,
+      '--premature-exit-guard-file',
+      guard_path
+    ]
+    run_common(cmd)
+
+def test_no_crash(bin_path, guard_path):
+    cmd = [
+      bin_path,
+      '--premature-exit-guard-file',
+      guard_path,
+      # Disable the quick-exit test
+      '~[quick_exit]'
+    ]
+    run_common(cmd)
+
+checks = {
+  'bazel': (test_bazel_env_vars, True),
+  'cli': (test_cli_parameter, True),
+  'no-crash': (test_no_crash, False),
+}
+
+
+bin_path = os.path.abspath(sys.argv[1])
+output_dir = os.path.abspath(sys.argv[2])
+test_kind = sys.argv[3]
+guard_file_path = os.path.join(output_dir, f"guard_file.{generate_path_suffix()}")
+print(f'Guard file path: "{guard_file_path}"')
+
+check_func, file_should_exist = checks[test_kind]
+check_func(bin_path, guard_file_path)
+
+assert os.path.exists(guard_file_path) == file_should_exist
+# With randomly generated file suffix, we should not run into name conflicts.
+# However, we try to cleanup anyway, to avoid having infinity files in
+# long living build directories.
+if file_should_exist:
+    try:
+        os.remove(guard_file_path)
+    except Exception as ex:
+        print(f'Could not remove file {guard_file_path} because: {ex}')
+