Optimize TestSuite comparison macro compile times.

src/Corrade/TestSuite/CMakeLists.txt

@@ -32,6 +32,7 @@ set(CorradeTestSuite_SRCS
     Comparator.cpp
     Tester.cpp
 
+    Compare/Container.cpp
     Compare/File.cpp
     Compare/FileToString.cpp
     Compare/FloatingPoint.cpp

src/Corrade/TestSuite/Comparator.cpp

@@ -27,6 +27,7 @@
 #include "Comparator.h"
 
 #include "Corrade/Containers/EnumSet.hpp"
+#include "Corrade/Containers/StringView.h"
 
 namespace Corrade { namespace TestSuite {
 
@@ -57,4 +58,22 @@ Utility::Debug& operator<<(Utility::Debug& debug, const ComparisonStatusFlags va
         ComparisonStatusFlag::VerboseDiagnostic});
 }
 
+namespace Implementation {
+
+void ComparatorBase::printMessage(ComparisonStatusFlags, Utility::Debug& out, const char* const actual, const char* const expected, void(*printer)(Utility::Debug&, const void*)) const {
+    CORRADE_INTERNAL_ASSERT(actualValue && expectedValue);
+    out << "Values" << actual << "and" << expected << "are not the same, actual is\n       ";
+    printer(out, actualValue);
+    out << Utility::Debug::newline << "        but expected\n       ";
+    printer(out, expectedValue);
+}
+
+/* LCOV_EXCL_START */
+void ComparatorBase::saveDiagnostic(ComparisonStatusFlags, Utility::Debug&, Containers::StringView) {
+    CORRADE_INTERNAL_ASSERT_UNREACHABLE();
+}
+/* LCOV_EXCL_STOP */
+
+}
+
 }}

src/Corrade/TestSuite/Comparator.h

@@ -110,6 +110,21 @@ CORRADE_TESTSUITE_EXPORT Utility::Debug& operator<<(Utility::Debug& debug, Compa
 /** @debugoperatorenum{ComparisonStatusFlags} */
 CORRADE_TESTSUITE_EXPORT Utility::Debug& operator<<(Utility::Debug& debug, ComparisonStatusFlags value);
 
+namespace Implementation {
+
+class CORRADE_TESTSUITE_EXPORT ComparatorBase {
+    public:
+        void saveDiagnostic(ComparisonStatusFlags status, Utility::Debug& out, Containers::StringView path); // TODO why even this??
+
+    protected:
+        void printMessage(ComparisonStatusFlags status, Utility::Debug& out, const char* actual, const char* expected, void(*printer)(Utility::Debug&, const void*)) const;
+
+        const void* actualValue{};
+        const void* expectedValue{};
+};
+
+}
+
 /**
 @brief Default comparator implementation
 
@@ -202,10 +217,8 @@ In the above case, the message will look for example like this:
 
 @include testsuite-save-diagnostic.ansi
 */
-template<class T> class Comparator {
+template<class T> class Comparator: public Implementation::ComparatorBase {
     public:
-        explicit Comparator();
-
         /**
          * @brief Compare two values
          *
@@ -230,6 +243,8 @@ template<class T> class Comparator {
          */
         void printMessage(ComparisonStatusFlags status, Utility::Debug& out, const char* actual, const char* expected);
 
+        /* Defined in the base class already */
+        #ifdef DOXYGEN_GENERATING_OUTPUT
         /**
          * @brief Save a diagnostic
          *
@@ -247,20 +262,10 @@ template<class T> class Comparator {
          * (and the function not being called at all if
          * @ref ComparisonStatusFlag::Diagnostic is not present as well).
          */
-        #ifdef DOXYGEN_GENERATING_OUTPUT
         void saveDiagnostic(ComparisonStatusFlags status, Utility::Debug& out, Containers::StringView path);
-        #else
-        /* using const& to avoid having to include StringView.h */
-        void saveDiagnostic(ComparisonStatusFlags status, Utility::Debug& out, const Containers::StringView& path);
         #endif
-
-    private:
-        const T* actualValue;
-        const T* expectedValue;
 };
 
-template<class T> Comparator<T>::Comparator(): actualValue(), expectedValue() {}
-
 template<class T> ComparisonStatusFlags Comparator<T>::operator()(const T& actual, const T& expected) {
     if(actual == expected) return {};
 
@@ -269,17 +274,12 @@ template<class T> ComparisonStatusFlags Comparator<T>::operator()(const T& actua
     return ComparisonStatusFlag::Failed;
 }
 
-template<class T> void Comparator<T>::printMessage(ComparisonStatusFlags, Utility::Debug& out, const char* actual, const char* expected) {
-    CORRADE_INTERNAL_ASSERT(actualValue && expectedValue);
-    out << "Values" << actual << "and" << expected << "are not the same, actual is\n       "
-      << *actualValue << Utility::Debug::newline << "        but expected\n       " << *expectedValue;
-}
-
-/* LCOV_EXCL_START */
-template<class T> void Comparator<T>::saveDiagnostic(ComparisonStatusFlags, Utility::Debug&, const Containers::StringView&) {
-    CORRADE_INTERNAL_ASSERT_UNREACHABLE();
+template<class T> void Comparator<T>::printMessage(const ComparisonStatusFlags status, Utility::Debug& out, const char* const actual, const char* const expected) {
+    Implementation::ComparatorBase::printMessage(status, out, actual, expected,
+        [](Utility::Debug& out, const void* value) {
+            out << *static_cast<const T*>(value);
+        });
 }
-/* LCOV_EXCL_STOP */
 
 namespace Implementation {
 

src/Corrade/TestSuite/Compare/Container.cpp

@@ -0,0 +1,62 @@
+/*
+    This file is part of Corrade.
+
+    Copyright © 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016,
+                2017, 2018, 2019, 2020, 2021, 2022
+              Vladimír Vondruš <mosra@centrum.cz>
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included
+    in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+*/
+
+#include "Container.h"
+
+namespace Corrade { namespace TestSuite { namespace Implementation {
+
+void ContainerComparatorBase::printMessage(ComparisonStatusFlags, Utility::Debug& out, const char* const actual, const char* const expected, void(*printer)(Utility::Debug&, const void*), void(*itemPrinter)(Utility::Debug&, const void*, std::size_t)) const {
+    CORRADE_INTERNAL_ASSERT(_actualContents && _expectedContents);
+
+    out << "Containers" << actual << "and" << expected << "have different";
+    if(_actualContentsSize != _expectedContentsSize)
+        out << "size, actual" << _actualContentsSize << "but" << _expectedContentsSize << "expected. Actual contents:\n       ";
+    else
+        out << "contents, actual:\n       ";
+
+    printer(out, _actualContents);
+    out << Utility::Debug::newline << "        but expected\n       ";
+    printer(out, _expectedContents);
+    out << Utility::Debug::newline << "       ";
+
+    if(_actualContentsSize <= _firstDifferent) {
+        out << "Expected has";
+        itemPrinter(out, _expectedContents, _firstDifferent);
+    } else if(_expectedContentsSize <= _firstDifferent) {
+        out << "Actual has";
+        itemPrinter(out, _actualContents, _firstDifferent);
+    } else {
+        out << "Actual";
+        itemPrinter(out, _actualContents, _firstDifferent);
+        out << "but";
+        itemPrinter(out, _expectedContents, _firstDifferent);
+        out << "expected";
+    }
+
+    out << "on position" << _firstDifferent << Utility::Debug::nospace << ".";
+}
+
+}}}

src/Corrade/TestSuite/Compare/Container.h

@@ -59,58 +59,65 @@ template<class> class Container {};
 
 }
 
+namespace Implementation {
+
+class CORRADE_TESTSUITE_EXPORT ContainerComparatorBase {
+    protected:
+        void printMessage(ComparisonStatusFlags status, Utility::Debug& out, const char* actual, const char* expected, void(*printer)(Utility::Debug&, const void*), void(*itemPrinter)(Utility::Debug&, const void*, std::size_t)) const;
+
+        const void* _actualContents{};
+        const void* _expectedContents{};
+        std::size_t _actualContentsSize{};
+        std::size_t _expectedContentsSize{};
+        std::size_t _firstDifferent{};
+};
+
+}
+
 #ifndef DOXYGEN_GENERATING_OUTPUT
-template<class T> class Comparator<Compare::Container<T>> {
+template<class T> class Comparator<Compare::Container<T>>: public Implementation::ContainerComparatorBase {
     public:
         ComparisonStatusFlags operator()(const T& actual, const T& expected);
 
         void printMessage(ComparisonStatusFlags, Utility::Debug& out, const char* actual, const char* expected) const;
-
-    private:
-        const T* _actualContents;
-        const T* _expectedContents;
 };
 
 template<class T> ComparisonStatusFlags Comparator<Compare::Container<T>>::operator()(const T& actual, const T& expected) {
     _actualContents = &actual;
     _expectedContents = &expected;
+    _actualContentsSize = actual.size();
+    _expectedContentsSize = expected.size();
+
+    ComparisonStatusFlags status;
+    if(_actualContentsSize != _expectedContentsSize)
+        status = ComparisonStatusFlag::Failed;
+
+    /* Recursively use the comparator on the values, find the first different
+       item in the common prefix. If there's none, then the first different
+       item is right after the common prefix, and if both have the same size
+       then it means the containers are the same. */
+    Comparator<typename std::decay<decltype(actual[0])>::type> comparator;
+    const std::size_t commonPrefixSize = Utility::min(_actualContentsSize, _expectedContentsSize);
+    _firstDifferent = commonPrefixSize;
+    for(std::size_t i = 0; i != commonPrefixSize; ++i) {
+        if(comparator(actual[i], expected[i]) & ComparisonStatusFlag::Failed) {
+            _firstDifferent = i;
+            status = ComparisonStatusFlag::Failed;
+            break;
+        }
+    }
 
-    if(_actualContents->size() != _expectedContents->size())
-        return ComparisonStatusFlag::Failed;
-
-    /* Recursively use comparator on the values */
-    Comparator<typename std::decay<decltype((*_actualContents)[0])>::type> comparator;
-    for(std::size_t i = 0; i != _actualContents->size(); ++i)
-        if(comparator((*_actualContents)[i], (*_expectedContents)[i]) & ComparisonStatusFlag::Failed)
-            return ComparisonStatusFlag::Failed;
-
-    return {};
+    return status;
 }
 
-template<class T> void Comparator<Compare::Container<T>>::printMessage(ComparisonStatusFlags, Utility::Debug& out, const char* actual, const char* expected) const {
-    out << "Containers" << actual << "and" << expected << "have different";
-    if(_actualContents->size() != _expectedContents->size())
-        out << "size, actual" << _actualContents->size() << "but" << _expectedContents->size() << "expected. Actual contents:\n       ";
-    else
-        out << "contents, actual:\n       ";
-
-    out << *_actualContents << Utility::Debug::newline << "        but expected\n       " << *_expectedContents << Utility::Debug::newline << "       ";
-
-    Comparator<typename std::decay<decltype((*_actualContents)[0])>::type> comparator;
-    for(std::size_t i = 0, end = Utility::max(_actualContents->size(), _expectedContents->size()); i != end; ++i) {
-        if(_actualContents->size() > i && _expectedContents->size() > i &&
-            !(comparator((*_actualContents)[i], (*_expectedContents)[i]) & ComparisonStatusFlag::Failed)) continue;
-
-        if(_actualContents->size() <= i)
-            out << "Expected has" << (*_expectedContents)[i];
-        else if(_expectedContents->size() <= i)
-            out << "Actual has" << (*_actualContents)[i];
-        else
-            out << "Actual" << (*_actualContents)[i] << "but" << (*_expectedContents)[i] << "expected";
-
-        out << "on position" << i << Utility::Debug::nospace << ".";
-        break;
-    }
+template<class T> void Comparator<Compare::Container<T>>::printMessage(const ComparisonStatusFlags status, Utility::Debug& out, const char* actual, const char* expected) const {
+    Implementation::ContainerComparatorBase::printMessage(status, out, actual, expected,
+        [](Utility::Debug& out, const void* contents) {
+            out << *static_cast<const T*>(contents);
+        },
+        [](Utility::Debug& out, const void* contents, std::size_t i) {
+            out << (*static_cast<const T*>(contents))[i];
+        });
 }
 #endif