Each reporter keeps its own colour implementation

This opens path to per-reporter colour output customization,
and fixes multiple issues with the old colour implementation.

Under the old implementation, using Win32-backed colouring
would always change the colour used by the console, even if the
actual output was written elsewhere, such as a file passed by
the `--out` flag. This will no longer happen, as the reporter's
colour impl will check that the reporter's stream is pointed
to console before trying to change the colours.

POSIX/ANSI colour implementation suffered a similar-ish issue,
in that it only wrote the colour escape codes into the default
output stream, even if the reporter asking for colouring was
actually writing to a completely different output stream.

src/catch2/catch_session.cpp

@@ -151,14 +151,16 @@ namespace Catch {
             getCurrentMutableContext().setConfig(m_config.get());
 
             m_startupExceptions = true;
-            Colour colourGuard( Colour::Red );
-            Catch::cerr() << "Errors occurred during startup!" << '\n';
+            auto errStream = makeStream( "%stderr" );
+            auto colourImpl = makeColourImpl( &config(), errStream.get() );
+            auto guard = colourImpl->startColour( Colour::Red );
+            errStream->stream() << "Errors occurred during startup!" << '\n';
             // iterate over all exceptions and notify user
             for ( const auto& ex_ptr : exceptions ) {
                 try {
                     std::rethrow_exception(ex_ptr);
                 } catch ( std::exception const& ex ) {
-                    Catch::cerr() << TextFlow::Column( ex.what() ).indent(2) << '\n';
+                    errStream->stream() << TextFlow::Column( ex.what() ).indent(2) << '\n';
                 }
             }
         }
@@ -194,12 +196,15 @@ namespace Catch {
         if( !result ) {
             config();
             getCurrentMutableContext().setConfig(m_config.get());
-            Catch::cerr()
-                << Colour( Colour::Red )
+            auto errStream = makeStream( "%stderr" );
+            auto colour = makeColourImpl( &config(), errStream.get() );
+
+            errStream->stream()
+                << colour->startColour( Colour::Red )
                 << "\nError(s) in input:\n"
                 << TextFlow::Column( result.errorMessage() ).indent( 2 )
                 << "\n\n";
-            Catch::cerr() << "Run with -? for usage\n\n" << std::flush;
+            errStream->stream() << "Run with -? for usage\n\n" << std::flush;
             return MaxExitCode;
         }
 

src/catch2/internal/catch_console_colour.cpp

@@ -24,23 +24,48 @@
 #include <ostream>
 
 namespace Catch {
+
+    ColourImpl::~ColourImpl() = default;
+
+    ColourImpl::ColourGuard ColourImpl::startColour( Colour::Code colourCode ) {
+        return ColourGuard(colourCode, this );
+    }
+
     namespace {
+        //! A do-nothing implementation of colour, used as fallback for unknown
+        //! platforms, and when the user asks to deactivate all colours.
+        class NoColourImpl : public ColourImpl {
+        public:
+            NoColourImpl( IStream const* stream ): ColourImpl( stream ) {}
+            static bool useColourOnPlatform() { return true; }
 
-        struct IColourImpl {
-            virtual ~IColourImpl() = default;
-            virtual void use( Colour::Code _colourCode ) = 0;
+        private:
+            void use( Colour::Code ) const override {}
         };
 
-        struct NoColourImpl : IColourImpl {
-            void use( Colour::Code ) override {}
+    } // namespace
 
-            static IColourImpl* instance() {
-                static NoColourImpl s_instance;
-                return &s_instance;
-            }
-        };
+    ColourImpl::ColourGuard::ColourGuard( Colour::Code code,
+                              ColourImpl const* colour ):
+        m_colourImpl( colour ) {
+        m_colourImpl->use( code );
+    }
+    ColourImpl::ColourGuard::ColourGuard( ColourGuard&& rhs ):
+        m_colourImpl( rhs.m_colourImpl ) {
+        rhs.m_moved = true;
+    }
+    ColourImpl::ColourGuard&
+    ColourImpl::ColourGuard::operator=( ColourGuard&& rhs ) {
+        m_colourImpl = rhs.m_colourImpl;
+        rhs.m_moved = true;
+        return *this;
+    }
+    ColourImpl::ColourGuard::~ColourGuard() {
+        if ( !m_moved ) {
+            m_colourImpl->use( Colour::None );
+        }
+    }
 
-    } // anon namespace
 } // namespace Catch
 
 #if !defined( CATCH_CONFIG_COLOUR_NONE ) && !defined( CATCH_CONFIG_COLOUR_WINDOWS ) && !defined( CATCH_CONFIG_COLOUR_ANSI )
@@ -57,9 +82,10 @@ namespace Catch {
 namespace Catch {
 namespace {
 
-    class Win32ColourImpl : public IColourImpl {
+    class Win32ColourImpl : public ColourImpl {
     public:
-        Win32ColourImpl() {
+        Win32ColourImpl(IStream const* stream):
+            ColourImpl(stream) {
             CONSOLE_SCREEN_BUFFER_INFO csbiInfo;
             GetConsoleScreenBufferInfo( GetStdHandle( STD_OUTPUT_HANDLE ),
                                         &csbiInfo );
@@ -67,7 +93,16 @@ namespace {
             originalBackgroundAttributes = csbiInfo.wAttributes & ~( FOREGROUND_GREEN | FOREGROUND_RED | FOREGROUND_BLUE | FOREGROUND_INTENSITY );
         }
 
-        void use( Colour::Code _colourCode ) override {
+        static bool useColourOnPlatform() { return true; }
+
+    private:
+        void use( Colour::Code _colourCode ) const override {
+            // Early exit if we are not writing to the console, because
+            // Win32 API can only change colour of the console.
+            if ( !m_stream->isStdout() ) {
+                return;
+            }
+
             switch( _colourCode ) {
                 case Colour::None:      return setTextAttribute( originalForegroundAttributes );
                 case Colour::White:     return setTextAttribute( FOREGROUND_GREEN | FOREGROUND_RED | FOREGROUND_BLUE );
@@ -91,8 +126,7 @@ namespace {
             }
         }
 
-    private:
-        void setTextAttribute( WORD _textAttribute ) {
+        void setTextAttribute( WORD _textAttribute ) const {
             SetConsoleTextAttribute( GetStdHandle( STD_OUTPUT_HANDLE ),
                                      _textAttribute |
                                          originalBackgroundAttributes );
@@ -101,19 +135,6 @@ namespace {
         WORD originalBackgroundAttributes;
     };
 
-    IColourImpl* platformColourInstance() {
-        static Win32ColourImpl s_instance;
-
-        auto const* config = getCurrentContext().getConfig();
-        UseColour colourMode = config?
-            config->useColour() : UseColour::Auto;
-        if( colourMode == UseColour::Auto )
-            colourMode = UseColour::Yes;
-        return colourMode == UseColour::Yes
-            ? &s_instance
-            : NoColourImpl::instance();
-    }
-
 } // end anon namespace
 } // end namespace Catch
 
@@ -128,9 +149,33 @@ namespace {
     // Thanks to Adam Strzelecki for original contribution
     // (http://github.com/nanoant)
     // https://github.com/philsquared/Catch/pull/131
-    class PosixColourImpl : public IColourImpl {
+    class PosixColourImpl : public ColourImpl {
     public:
-        void use( Colour::Code _colourCode ) override {
+        PosixColourImpl( IStream const* stream ): ColourImpl( stream ) {}
+
+        static bool useColourOnPlatform() {
+            ErrnoGuard _; // for isatty
+            return
+#    if defined( CATCH_PLATFORM_MAC ) || defined( CATCH_PLATFORM_IPHONE )
+                !isDebuggerActive() &&
+#    endif
+#    if !( defined( __DJGPP__ ) && defined( __STRICT_ANSI__ ) )
+                isatty( STDOUT_FILENO )
+#    else
+                false
+#    endif
+                    ;
+        }
+
+    private:
+        void use( Colour::Code _colourCode ) const override {
+            auto setColour = [&out =
+                                  m_stream->stream()]( char const* escapeCode ) {
+                // The escape sequence must be flushed to console, otherwise
+                // if stdin and stderr are intermixed, we'd get accidentally
+                // coloured output.
+                out << '\033' << escapeCode << std::flush;
+            };
             switch( _colourCode ) {
                 case Colour::None:
                 case Colour::White:     return setColour( "[0m" );
@@ -151,89 +196,52 @@ namespace {
                 default: CATCH_INTERNAL_ERROR( "Unknown colour requested" );
             }
         }
-        static IColourImpl* instance() {
-            static PosixColourImpl s_instance;
-            return &s_instance;
-        }
-
-    private:
-        void setColour( const char* _escapeCode ) {
-            // The escape sequence must be flushed to console, otherwise if
-            // stdin and stderr are intermixed, we'd get accidentally coloured output.
-            getCurrentContext().getConfig()->defaultStream()->stream()
-                << '\033' << _escapeCode << std::flush;
-        }
     };
 
-    bool useColourOnPlatform() {
-        return
-#if defined(CATCH_PLATFORM_MAC) || defined(CATCH_PLATFORM_IPHONE)
-            !isDebuggerActive() &&
-#endif
-#if !(defined(__DJGPP__) && defined(__STRICT_ANSI__))
-            isatty(STDOUT_FILENO)
-#else
-            false
-#endif
-            ;
-    }
-    IColourImpl* platformColourInstance() {
-        ErrnoGuard guard;
-        auto const* config = getCurrentContext().getConfig();
-        UseColour colourMode = config
-            ? config->useColour()
-            : UseColour::Auto;
-        if( colourMode == UseColour::Auto )
-            colourMode = useColourOnPlatform()
-                ? UseColour::Yes
-                : UseColour::No;
-        return colourMode == UseColour::Yes
-            ? PosixColourImpl::instance()
-            : NoColourImpl::instance();
-    }
-
 } // end anon namespace
 } // end namespace Catch
 
-#else  // not Windows or ANSI ///////////////////////////////////////////////
-
-namespace Catch {
-
-    static IColourImpl* platformColourInstance() { return NoColourImpl::instance(); }
-
-} // end namespace Catch
-
 #endif // Windows/ ANSI/ None
 
 namespace Catch {
 
-    Colour::Colour( Code _colourCode ) { use( _colourCode ); }
-    Colour::Colour( Colour&& other ) noexcept {
-        m_moved = other.m_moved;
-        other.m_moved = true;
-    }
-    Colour& Colour::operator=( Colour&& other ) noexcept {
-        m_moved = other.m_moved;
-        other.m_moved  = true;
-        return *this;
-    }
+    Detail::unique_ptr<ColourImpl> makeColourImpl(IConfig const* config, IStream const* stream) {
+        UseColour colourMode = config ? config->useColour() : UseColour::Auto;
 
-    Colour::~Colour(){ if( !m_moved ) use( None ); }
-
-    void Colour::use( Code _colourCode ) {
-        static IColourImpl* impl = platformColourInstance();
-        // Strictly speaking, this cannot possibly happen.
-        // However, under some conditions it does happen (see #1626),
-        // and this change is small enough that we can let practicality
-        // triumph over purity in this case.
-        if (impl != nullptr) {
-            impl->use( _colourCode );
+        bool createPlatformInstance = false;
+        if ( colourMode == UseColour::No ) {
+            createPlatformInstance = false;
         }
+
+        if ( colourMode == UseColour::Yes ) {
+            createPlatformInstance = true;
+        }
+
+        if ( colourMode == UseColour::Auto ) {
+            createPlatformInstance =
+#if defined( CATCH_CONFIG_COLOUR_ANSI )
+                PosixColourImpl::useColourOnPlatform()
+#elif defined( CATCH_CONFIG_COLOUR_WINDOWS )
+                Win32ColourImpl::useColourOnPlatform()
+#else
+                NoColourImpl::useColourOnPlatform()
+#endif
+                ;
+        }
+
+        if ( createPlatformInstance ) {
+            return
+#if defined( CATCH_CONFIG_COLOUR_ANSI )
+                Detail::make_unique<PosixColourImpl>(stream);
+#elif defined( CATCH_CONFIG_COLOUR_WINDOWS )
+                Detail::make_unique<Win32ColourImpl>(stream);
+#else
+                Detail::make_unique<NoColourImpl>(stream);
+#endif
+        }
+        return Detail::make_unique<NoColourImpl>(stream);
     }
 
-    std::ostream& operator << ( std::ostream& os, Colour const& ) {
-        return os;
-    }
 
 } // end namespace Catch
 

src/catch2/internal/catch_console_colour.hpp

@@ -8,10 +8,15 @@
 #ifndef CATCH_CONSOLE_COLOUR_HPP_INCLUDED
 #define CATCH_CONSOLE_COLOUR_HPP_INCLUDED
 
+#include <catch2/internal/catch_unique_ptr.hpp>
+
 #include <iosfwd>
 
 namespace Catch {
 
+    struct IConfig;
+    class IStream;
+
     struct Colour {
         enum Code {
             None = 0,
@@ -48,22 +53,41 @@ namespace Catch {
             SecondaryText = LightGrey,
             Headers = White
         };
-
-        // Use constructed object for RAII guard
-        Colour( Code _colourCode );
-        Colour( Colour&& other ) noexcept;
-        Colour& operator=( Colour&& other ) noexcept;
-        ~Colour();
-
-        // Use static method for one-shot changes
-        static void use( Code _colourCode );
-
-    private:
-        bool m_moved = false;
-
-        friend std::ostream& operator << (std::ostream& os, Colour const&);
     };
 
+    class ColourImpl {
+    protected:
+        //! The associated stream of this ColourImpl instance
+        IStream const* m_stream;
+    public:
+        ColourImpl( IStream const* stream ): m_stream( stream ) {}
+
+        class ColourGuard {
+            ColourImpl const* m_colourImpl;
+            bool m_moved = false;
+            friend std::ostream& operator<<(std::ostream& lhs,
+                                            ColourGuard const&) {
+                return lhs;
+            }
+        public:
+            ColourGuard( Colour::Code code,
+                         ColourImpl const* colour );
+            ColourGuard( ColourGuard const& rhs ) = delete;
+            ColourGuard& operator=( ColourGuard const& rhs ) = delete;
+            ColourGuard( ColourGuard&& rhs );
+            ColourGuard& operator=( ColourGuard&& rhs );
+            ~ColourGuard();
+        };
+
+        virtual ~ColourImpl(); // = default
+        ColourGuard startColour( Colour::Code colourCode );
+
+    private:
+        virtual void use( Colour::Code colourCode ) const = 0;
+    };
+
+    //! Provides ColourImpl based on global config and target compilation platform
+    Detail::unique_ptr<ColourImpl> makeColourImpl( IConfig const* config, IStream const* stream );
 
 } // end namespace Catch
 

src/catch2/reporters/catch_reporter_combined_tu.cpp

@@ -174,7 +174,7 @@ namespace Catch {
         out << pluralise(tags.size(), "tag"_sr) << "\n\n" << std::flush;
     }
 
-    void defaultListTests(std::ostream& out, std::vector<TestCaseHandle> const& tests, bool isFiltered, Verbosity verbosity) {
+    void defaultListTests(std::ostream& out, ColourImpl* streamColour, std::vector<TestCaseHandle> const& tests, bool isFiltered, Verbosity verbosity) {
         // We special case this to provide the equivalent of old
         // `--list-test-names-only`, which could then be used by the
         // `--input-file` option.
@@ -194,7 +194,7 @@ namespace Catch {
             Colour::Code colour = testCaseInfo.isHidden()
                 ? Colour::SecondaryText
                 : Colour::None;
-            Colour colourGuard(colour);
+            auto colourGuard = streamColour->startColour( colour );
 
             out << TextFlow::Column(testCaseInfo.name).initialIndent(2).indent(4) << '\n';
             if (verbosity >= Verbosity::High) {

src/catch2/reporters/catch_reporter_common_base.cpp

@@ -18,6 +18,7 @@ namespace Catch {
 
     void ReporterBase::listTests(std::vector<TestCaseHandle> const& tests) {
         defaultListTests(m_stream,
+                         m_colour.get(),
                          tests,
                          m_config->hasTestFilters(),
                          m_config->verbosity());

src/catch2/reporters/catch_reporter_common_base.hpp

@@ -10,6 +10,7 @@
 
 #include <catch2/interfaces/catch_interfaces_reporter.hpp>
 #include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_console_colour.hpp>
 
 namespace Catch {
     /**
@@ -29,14 +30,14 @@ namespace Catch {
         //! Cached output stream from `m_wrapped_stream` to reduce
         //! number of indirect calls needed to write output.
         std::ostream& m_stream;
-
-
+        Detail::unique_ptr<ColourImpl> m_colour;
 
     public:
         ReporterBase( ReporterConfig const& config ):
             IEventListener( config.fullConfig() ),
             m_wrapped_stream( config.stream() ),
-            m_stream( m_wrapped_stream->stream() ) {}
+            m_stream( m_wrapped_stream->stream() ),
+            m_colour( makeColourImpl( config.fullConfig(), m_wrapped_stream ) ) {}
 
 
         /**

src/catch2/reporters/catch_reporter_compact.cpp

@@ -18,9 +18,6 @@
 
 namespace {
 
-    // Colour::LightGrey
-    constexpr Catch::Colour::Code dimColour() { return Catch::Colour::FileName; }
-
     constexpr Catch::StringRef bothOrAll( std::uint64_t count ) {
         switch (count) {
         case 1:
@@ -38,6 +35,9 @@ namespace {
 namespace Catch {
 namespace {
 
+    // Colour::LightGrey
+    static constexpr Colour::Code compactDimColour = Colour::FileName;
+
 #ifdef CATCH_PLATFORM_MAC
     static constexpr Catch::StringRef compactFailedString = "FAILED"_sr;
     static constexpr Catch::StringRef compactPassedString = "PASSED"_sr;
@@ -52,11 +52,11 @@ namespace {
 // - white: Passed [both/all] N test cases (no assertions).
 // -   red: Failed N tests cases, failed M assertions.
 // - green: Passed [both/all] N tests cases with M assertions.
-void printTotals(std::ostream& out, const Totals& totals) {
+void printTotals(std::ostream& out, const Totals& totals, ColourImpl* colourImpl) {
     if (totals.testCases.total() == 0) {
         out << "No tests ran.";
     } else if (totals.testCases.failed == totals.testCases.total()) {
-        Colour colour(Colour::ResultError);
+        auto guard = colourImpl->startColour( Colour::ResultError );
         const StringRef qualify_assertions_failed =
             totals.assertions.failed == totals.assertions.total() ?
             bothOrAll(totals.assertions.failed) : StringRef{};
@@ -71,13 +71,11 @@ void printTotals(std::ostream& out, const Totals& totals) {
             << pluralise(totals.testCases.total(), "test case"_sr)
             << " (no assertions).";
     } else if (totals.assertions.failed) {
-        Colour colour(Colour::ResultError);
-        out <<
+        out << colourImpl->startColour( Colour::ResultError ) <<
             "Failed " << pluralise(totals.testCases.failed, "test case"_sr) << ", "
             "failed " << pluralise(totals.assertions.failed, "assertion"_sr) << '.';
     } else {
-        Colour colour(Colour::ResultSuccess);
-        out <<
+        out << colourImpl->startColour( Colour::ResultSuccess ) <<
             "Passed " << bothOrAll(totals.testCases.passed)
             << pluralise(totals.testCases.passed, "test case"_sr) <<
             " with " << pluralise(totals.assertions.passed, "assertion"_sr) << '.';
@@ -89,12 +87,14 @@ class AssertionPrinter {
 public:
     AssertionPrinter& operator= (AssertionPrinter const&) = delete;
     AssertionPrinter(AssertionPrinter const&) = delete;
-    AssertionPrinter(std::ostream& _stream, AssertionStats const& _stats, bool _printInfoMessages)
+    AssertionPrinter(std::ostream& _stream, AssertionStats const& _stats, bool _printInfoMessages, ColourImpl* colourImpl_)
         : stream(_stream)
         , result(_stats.assertionResult)
         , messages(_stats.infoMessages)
         , itMessage(_stats.infoMessages.begin())
-        , printInfoMessages(_printInfoMessages) {}
+        , printInfoMessages(_printInfoMessages)
+        , colourImpl(colourImpl_)
+    {}
 
     void print() {
         printSourceInfo();
@@ -166,16 +166,13 @@ public:
 
 private:
     void printSourceInfo() const {
-        Colour colourGuard(Colour::FileName);
-        stream << result.getSourceInfo() << ':';
+        stream << colourImpl->startColour( Colour::FileName )
+               << result.getSourceInfo() << ':';
     }
 
     void printResultType(Colour::Code colour, StringRef passOrFail) const {
         if (!passOrFail.empty()) {
-            {
-                Colour colourGuard(colour);
-                stream << ' ' << passOrFail;
-            }
+            stream << colourImpl->startColour(colour) << ' ' << passOrFail;
             stream << ':';
         }
     }
@@ -188,8 +185,7 @@ private:
         if (result.hasExpression()) {
             stream << ';';
             {
-                Colour colour(dimColour());
-                stream << " expression was:";
+                stream << colourImpl->startColour(compactDimColour) << " expression was:";
             }
             printOriginalExpression();
         }
@@ -203,10 +199,7 @@ private:
 
     void printReconstructedExpression() const {
         if (result.hasExpandedExpression()) {
-            {
-                Colour colour(dimColour());
-                stream << " for: ";
-            }
+            stream << colourImpl->startColour(compactDimColour) << " for: ";
             stream << result.getExpandedExpression();
         }
     }
@@ -218,25 +211,22 @@ private:
         }
     }
 
-    void printRemainingMessages(Colour::Code colour = dimColour()) {
+    void printRemainingMessages(Colour::Code colour = compactDimColour) {
         if (itMessage == messages.end())
             return;
 
         const auto itEnd = messages.cend();
         const auto N = static_cast<std::size_t>(std::distance(itMessage, itEnd));
 
-        {
-            Colour colourGuard(colour);
-            stream << " with " << pluralise(N, "message"_sr) << ':';
-        }
+        stream << colourImpl->startColour( colour ) << " with "
+               << pluralise( N, "message"_sr ) << ':';
 
         while (itMessage != itEnd) {
             // If this assertion is a warning ignore any INFO messages
             if (printInfoMessages || itMessage->type != ResultWas::Info) {
                 printMessage();
                 if (itMessage != itEnd) {
-                    Colour colourGuard(dimColour());
-                    stream << " and";
+                    stream << colourImpl->startColour(compactDimColour) << " and";
                 }
                 continue;
             }
@@ -250,6 +240,7 @@ private:
     std::vector<MessageInfo> messages;
     std::vector<MessageInfo>::const_iterator itMessage;
     bool printInfoMessages;
+    ColourImpl* colourImpl;
 };
 
 } // anon namespace
@@ -274,7 +265,7 @@ private:
                 printInfoMessages = false;
             }
 
-            AssertionPrinter printer( m_stream, _assertionStats, printInfoMessages );
+            AssertionPrinter printer( m_stream, _assertionStats, printInfoMessages, m_colour.get() );
             printer.print();
 
             m_stream << '\n' << std::flush;
@@ -288,7 +279,7 @@ private:
         }
 
         void CompactReporter::testRunEnded( TestRunStats const& _testRunStats ) {
-            printTotals( m_stream, _testRunStats.totals );
+            printTotals( m_stream, _testRunStats.totals, m_colour.get() );
             m_stream << "\n\n" << std::flush;
             StreamingReporterBase::testRunEnded( _testRunStats );
         }

src/catch2/reporters/catch_reporter_console.cpp

@@ -45,13 +45,14 @@ class ConsoleAssertionPrinter {
 public:
     ConsoleAssertionPrinter& operator= (ConsoleAssertionPrinter const&) = delete;
     ConsoleAssertionPrinter(ConsoleAssertionPrinter const&) = delete;
-    ConsoleAssertionPrinter(std::ostream& _stream, AssertionStats const& _stats, bool _printInfoMessages)
+    ConsoleAssertionPrinter(std::ostream& _stream, AssertionStats const& _stats, ColourImpl* colourImpl_, bool _printInfoMessages)
         : stream(_stream),
         stats(_stats),
         result(_stats.assertionResult),
         colour(Colour::None),
         message(result.getMessage()),
         messages(_stats.infoMessages),
+        colourImpl(colourImpl_),
         printInfoMessages(_printInfoMessages) {
         switch (result.getResultType()) {
         case ResultWas::Ok:
@@ -134,23 +135,22 @@ public:
 private:
     void printResultType() const {
         if (!passOrFail.empty()) {
-            Colour colourGuard(colour);
-            stream << passOrFail << ":\n";
+            stream << colourImpl->startColour(colour) << passOrFail << ":\n";
         }
     }
     void printOriginalExpression() const {
         if (result.hasExpression()) {
-            Colour colourGuard(Colour::OriginalExpression);
-            stream << "  ";
-            stream << result.getExpressionInMacro();
-            stream << '\n';
+            stream << colourImpl->startColour( Colour::OriginalExpression )
+                   << "  " << result.getExpressionInMacro() << '\n';
         }
     }
     void printReconstructedExpression() const {
         if (result.hasExpandedExpression()) {
             stream << "with expansion:\n";
-            Colour colourGuard(Colour::ReconstructedExpression);
-            stream << TextFlow::Column(result.getExpandedExpression()).indent(2) << '\n';
+            stream << colourImpl->startColour( Colour::ReconstructedExpression )
+                   << TextFlow::Column( result.getExpandedExpression() )
+                          .indent( 2 )
+                   << '\n';
         }
     }
     void printMessage() const {
@@ -163,8 +163,8 @@ private:
         }
     }
     void printSourceInfo() const {
-        Colour colourGuard(Colour::FileName);
-        stream << result.getSourceInfo() << ": ";
+        stream << colourImpl->startColour( Colour::FileName )
+               << result.getSourceInfo() << ": ";
     }
 
     std::ostream& stream;
@@ -175,6 +175,7 @@ private:
     std::string messageLabel;
     std::string message;
     std::vector<MessageInfo> messages;
+    ColourImpl* colourImpl;
     bool printInfoMessages;
 };
 
@@ -403,7 +404,7 @@ void ConsoleReporter::assertionEnded(AssertionStats const& _assertionStats) {
 
     lazyPrint();
 
-    ConsoleAssertionPrinter printer(m_stream, _assertionStats, includeResults);
+    ConsoleAssertionPrinter printer(m_stream, _assertionStats, m_colour.get(), includeResults);
     printer.print();
     m_stream << '\n' << std::flush;
 }
@@ -417,7 +418,7 @@ void ConsoleReporter::sectionEnded(SectionStats const& _sectionStats) {
     m_tablePrinter->close();
     if (_sectionStats.missingAssertions) {
         lazyPrint();
-        Colour colour(Colour::ResultError);
+        auto guard = m_colour->startColour( Colour::ResultError );
         if (m_sectionStack.size() > 1)
             m_stream << "\nNo assertions in section";
         else
@@ -475,7 +476,7 @@ void ConsoleReporter::benchmarkEnded(BenchmarkStats<> const& stats) {
 }
 
 void ConsoleReporter::benchmarkFailed( StringRef error ) {
-	Colour colour(Colour::Red);
+    auto guard = m_colour->startColour( Colour::Red );
     (*m_tablePrinter)
         << "Benchmark failed (" << error << ')'
         << ColumnBreak() << RowBreak();
@@ -514,13 +515,13 @@ void ConsoleReporter::lazyPrintWithoutClosingBenchmarkTable() {
     }
 }
 void ConsoleReporter::lazyPrintRunInfo() {
-    m_stream << '\n' << lineOfChars('~') << '\n';
-    Colour colour(Colour::SecondaryText);
-    m_stream << currentTestRunInfo.name
-        << " is a Catch2 v" << libraryVersion() << " host application.\n"
-        << "Run with -? for options\n\n";
-
-    m_stream << "Randomness seeded to: " << m_config->rngSeed() << "\n\n";
+    m_stream << '\n'
+             << lineOfChars( '~' ) << '\n'
+             << m_colour->startColour( Colour::SecondaryText )
+             << currentTestRunInfo.name << " is a Catch2 v" << libraryVersion()
+             << " host application.\n"
+             << "Run with -? for options\n\n"
+             << "Randomness seeded to: " << m_config->rngSeed() << "\n\n";
 
     m_testRunInfoPrinted = true;
 }
@@ -529,7 +530,7 @@ void ConsoleReporter::printTestCaseAndSectionHeader() {
     printOpenHeader(currentTestCaseInfo->name);
 
     if (m_sectionStack.size() > 1) {
-        Colour colourGuard(Colour::Headers);
+        auto guard = m_colour->startColour( Colour::Headers );
 
         auto
             it = m_sectionStack.begin() + 1, // Skip first section (test case)
@@ -541,10 +542,10 @@ void ConsoleReporter::printTestCaseAndSectionHeader() {
     SourceLineInfo lineInfo = m_sectionStack.back().lineInfo;
 
 
-    m_stream << lineOfChars('-') << '\n';
-    Colour colourGuard(Colour::FileName);
-    m_stream << lineInfo << '\n';
-    m_stream << lineOfChars('.') << "\n\n" << std::flush;
+    m_stream << lineOfChars( '-' ) << '\n'
+             << m_colour->startColour( Colour::FileName ) << lineInfo << '\n'
+             << lineOfChars( '.' ) << "\n\n"
+             << std::flush;
 }
 
 void ConsoleReporter::printClosedHeader(std::string const& _name) {
@@ -554,7 +555,7 @@ void ConsoleReporter::printClosedHeader(std::string const& _name) {
 void ConsoleReporter::printOpenHeader(std::string const& _name) {
     m_stream << lineOfChars('-') << '\n';
     {
-        Colour colourGuard(Colour::Headers);
+        auto guard = m_colour->startColour( Colour::Headers );
         printHeaderString(_name);
     }
 }
@@ -619,9 +620,11 @@ struct SummaryColumn {
 
 void ConsoleReporter::printTotals( Totals const& totals ) {
     if (totals.testCases.total() == 0) {
-        m_stream << Colour(Colour::Warning) << "No tests ran\n";
+        m_stream << m_colour->startColour( Colour::Warning )
+                 << "No tests ran\n";
     } else if (totals.assertions.total() > 0 && totals.testCases.allPassed()) {
-        m_stream << Colour(Colour::ResultSuccess) << "All tests passed";
+        m_stream << m_colour->startColour( Colour::ResultSuccess )
+                 << "All tests passed";
         m_stream << " ("
             << pluralise(totals.assertions.passed, "assertion"_sr) << " in "
             << pluralise(totals.testCases.passed, "test case"_sr) << ')'
@@ -648,17 +651,19 @@ void ConsoleReporter::printTotals( Totals const& totals ) {
 }
 void ConsoleReporter::printSummaryRow(StringRef label, std::vector<SummaryColumn> const& cols, std::size_t row) {
     for (auto col : cols) {
-        std::string value = col.rows[row];
+        std::string const& value = col.rows[row];
         if (col.label.empty()) {
             m_stream << label << ": ";
-            if (value != "0")
+            if ( value != "0" ) {
                 m_stream << value;
-            else
-                m_stream << Colour(Colour::Warning) << "- none -";
+            } else {
+                m_stream << m_colour->startColour( Colour::Warning )
+                         << "- none -";
+            }
         } else if (value != "0") {
-            m_stream << Colour(Colour::LightGrey) << " | ";
-            m_stream << Colour(col.colour)
-                << value << ' ' << col.label;
+            m_stream << m_colour->startColour( Colour::LightGrey ) << " | "
+                     << m_colour->startColour( col.colour ) << value << ' '
+                     << col.label;
         }
     }
     m_stream << '\n';
@@ -674,14 +679,20 @@ void ConsoleReporter::printTotalsDivider(Totals const& totals) {
         while (failedRatio + failedButOkRatio + passedRatio > CATCH_CONFIG_CONSOLE_WIDTH - 1)
             findMax(failedRatio, failedButOkRatio, passedRatio)--;
 
-        m_stream << Colour(Colour::Error) << std::string(failedRatio, '=');
-        m_stream << Colour(Colour::ResultExpectedFailure) << std::string(failedButOkRatio, '=');
-        if (totals.testCases.allPassed())
-            m_stream << Colour(Colour::ResultSuccess) << std::string(passedRatio, '=');
-        else
-            m_stream << Colour(Colour::Success) << std::string(passedRatio, '=');
+        m_stream << m_colour->startColour( Colour::Error )
+                 << std::string( failedRatio, '=' )
+                 << m_colour->startColour( Colour::ResultExpectedFailure )
+                 << std::string( failedButOkRatio, '=' );
+        if ( totals.testCases.allPassed() ) {
+            m_stream << m_colour->startColour( Colour::ResultSuccess )
+                     << std::string( passedRatio, '=' );
+        } else {
+            m_stream << m_colour->startColour( Colour::Success )
+                     << std::string( passedRatio, '=' );
+        }
     } else {
-        m_stream << Colour(Colour::Warning) << std::string(CATCH_CONFIG_CONSOLE_WIDTH - 1, '=');
+        m_stream << m_colour->startColour( Colour::Warning )
+                 << std::string( CATCH_CONFIG_CONSOLE_WIDTH - 1, '=' );
     }
     m_stream << '\n';
 }
@@ -691,8 +702,8 @@ void ConsoleReporter::printSummaryDivider() {
 
 void ConsoleReporter::printTestFilters() {
     if (m_config->testSpec().hasFilters()) {
-        Colour guard(Colour::BrightYellow);
-        m_stream << "Filters: " << serializeFilters(m_config->getTestsOrTags()) << '\n';
+        m_stream << m_colour->startColour( Colour::BrightYellow ) << "Filters: "
+                 << serializeFilters( m_config->getTestsOrTags() ) << '\n';
     }
 }
 

src/catch2/reporters/catch_reporter_helpers.hpp

@@ -19,6 +19,7 @@ namespace Catch {
 
     struct IConfig;
     class TestCaseHandle;
+    class ColourImpl;
 
     // Returns double formatted as %.3f (format expected on output)
     std::string getFormattedDuration( double duration );
@@ -67,6 +68,7 @@ namespace Catch {
      * `--list-test-names-only` option, for people who used it in integrations.
      */
     void defaultListTests( std::ostream& out,
+                           ColourImpl* streamColour,
                            std::vector<TestCaseHandle> const& tests,
                            bool isFiltered,
                            Verbosity verbosity );

src/catch2/reporters/catch_reporter_tap.cpp

@@ -20,18 +20,20 @@ namespace Catch {
         // Making older compiler happy is hard.
         static constexpr StringRef tapFailedString = "not ok"_sr;
         static constexpr StringRef tapPassedString = "ok"_sr;
+        static constexpr Colour::Code tapDimColour = Colour::FileName;
 
         class TapAssertionPrinter {
         public:
             TapAssertionPrinter& operator= (TapAssertionPrinter const&) = delete;
             TapAssertionPrinter(TapAssertionPrinter const&) = delete;
-            TapAssertionPrinter(std::ostream& _stream, AssertionStats const& _stats, std::size_t _counter)
+            TapAssertionPrinter(std::ostream& _stream, AssertionStats const& _stats, std::size_t _counter, ColourImpl* colour_)
                 : stream(_stream)
                 , result(_stats.assertionResult)
                 , messages(_stats.infoMessages)
                 , itMessage(_stats.infoMessages.begin())
                 , printInfoMessages(true)
-                , counter(_counter) {}
+                , counter(_counter)
+                , colourImpl( colour_ ) {}
 
             void print() {
                 itMessage = messages.begin();
@@ -104,11 +106,9 @@ namespace Catch {
             }
 
         private:
-            static Colour::Code dimColour() { return Colour::FileName; }
-
             void printSourceInfo() const {
-                Colour colourGuard(dimColour());
-                stream << result.getSourceInfo() << ':';
+                stream << colourImpl->startColour( tapDimColour )
+                       << result.getSourceInfo() << ':';
             }
 
             void printResultType(StringRef passOrFail) const {
@@ -124,10 +124,8 @@ namespace Catch {
             void printExpressionWas() {
                 if (result.hasExpression()) {
                     stream << ';';
-                    {
-                        Colour colour(dimColour());
-                        stream << " expression was:";
-                    }
+                    stream << colourImpl->startColour( tapDimColour )
+                           << " expression was:";
                     printOriginalExpression();
                 }
             }
@@ -140,10 +138,8 @@ namespace Catch {
 
             void printReconstructedExpression() const {
                 if (result.hasExpandedExpression()) {
-                    {
-                        Colour colour(dimColour());
-                        stream << " for: ";
-                    }
+                    stream << colourImpl->startColour( tapDimColour ) << " for: ";
+
                     std::string expr = result.getExpandedExpression();
                     std::replace(expr.begin(), expr.end(), '\n', ' ');
                     stream << expr;
@@ -157,7 +153,7 @@ namespace Catch {
                 }
             }
 
-            void printRemainingMessages(Colour::Code colour = dimColour()) {
+            void printRemainingMessages(Colour::Code colour = tapDimColour) {
                 if (itMessage == messages.end()) {
                     return;
                 }
@@ -166,18 +162,15 @@ namespace Catch {
                 std::vector<MessageInfo>::const_iterator itEnd = messages.end();
                 const std::size_t N = static_cast<std::size_t>(std::distance(itMessage, itEnd));
 
-                {
-                    Colour colourGuard(colour);
-                    stream << " with " << pluralise(N, "message"_sr) << ':';
-                }
+                stream << colourImpl->startColour( colour ) << " with "
+                       << pluralise( N, "message"_sr ) << ':';
 
                 for (; itMessage != itEnd; ) {
                     // If this assertion is a warning ignore any INFO messages
                     if (printInfoMessages || itMessage->type != ResultWas::Info) {
                         stream << " '" << itMessage->message << '\'';
                         if (++itMessage != itEnd) {
-                            Colour colourGuard(dimColour());
-                            stream << " and";
+                            stream << colourImpl->startColour(tapDimColour) << " and";
                         }
                     }
                 }
@@ -190,6 +183,7 @@ namespace Catch {
             std::vector<MessageInfo>::const_iterator itMessage;
             bool printInfoMessages;
             std::size_t counter;
+            ColourImpl* colourImpl;
         };
 
     } // End anonymous namespace
@@ -202,7 +196,7 @@ namespace Catch {
         ++counter;
 
         m_stream << "# " << currentTestCaseInfo->name << '\n';
-        TapAssertionPrinter printer(m_stream, _assertionStats, counter);
+        TapAssertionPrinter printer(m_stream, _assertionStats, counter, m_colour.get());
         printer.print();
 
         m_stream << '\n' << std::flush;

tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp

@@ -13,6 +13,7 @@
 #include <catch2/interfaces/catch_interfaces_reporter.hpp>
 #include <catch2/interfaces/catch_interfaces_reporter_factory.hpp>
 #include <catch2/interfaces/catch_interfaces_reporter_registry.hpp>
+#include <catch2/internal/catch_console_colour.hpp>
 #include <catch2/internal/catch_enforce.hpp>
 #include <catch2/internal/catch_list.hpp>
 #include <catch2/internal/catch_reporter_registry.hpp>
@@ -40,11 +41,11 @@ TEST_CASE( "The default listing implementation write to provided stream",
     using Catch::Matchers::ContainsSubstring;
     using namespace std::string_literals;
 
-    std::stringstream sstream;
+    StringIStream sstream;
     SECTION( "Listing tags" ) {
         std::vector<Catch::TagInfo> tags(1);
         tags[0].add("fakeTag"_catch_sr);
-        Catch::defaultListTags(sstream, tags, false);
+        Catch::defaultListTags(sstream.stream(), tags, false);
 
         auto listingString = sstream.str();
         REQUIRE_THAT(listingString, ContainsSubstring("[fakeTag]"s));
@@ -52,7 +53,7 @@ TEST_CASE( "The default listing implementation write to provided stream",
     SECTION( "Listing reporters" ) {
         std::vector<Catch::ReporterDescription> reporters(
             { { "fake reporter", "fake description" } } );
-        Catch::defaultListReporters(sstream, reporters, Catch::Verbosity::Normal);
+        Catch::defaultListReporters(sstream.stream(), reporters, Catch::Verbosity::Normal);
 
         auto listingString = sstream.str();
         REQUIRE_THAT(listingString, ContainsSubstring("fake reporter"s));
@@ -63,7 +64,11 @@ TEST_CASE( "The default listing implementation write to provided stream",
             { "fake test name"_catch_sr, "[fakeTestTag]"_catch_sr },
             { "fake-file.cpp", 123456789 } };
         std::vector<Catch::TestCaseHandle> tests({ {&fakeInfo, nullptr} });
-        Catch::defaultListTests(sstream, tests, false, Catch::Verbosity::Normal);
+        Catch::ConfigData cd;
+        cd.useColour = Catch::UseColour::No;
+        Catch::Config conf(cd);
+        auto colour = Catch::makeColourImpl( &conf, &sstream);
+        Catch::defaultListTests(sstream.stream(), colour.get(), tests, false, Catch::Verbosity::Normal);
 
         auto listingString = sstream.str();
         REQUIRE_THAT( listingString,