Add constexpr to Vector{2,3,4} and Vector<N, T>

src/Magnum/Math/BitVector.h

@@ -35,6 +35,7 @@
 #ifndef CORRADE_NO_DEBUG
 #include <Corrade/Utility/Debug.h>
 #endif
+#include <Corrade/Utility/Macros.h>
 
 #include "Magnum/Types.h"
 #include "Magnum/Math/Math.h"
@@ -174,14 +175,14 @@ template<std::size_t size> class BitVector {
          * Equivalent to @ref all().
          * @see @ref any(), @ref none()
          */
-        explicit operator bool() const { return all(); }
+        explicit MAGNUM_CONSTEXPR14 operator bool() const { return all(); }
 
         /**
          * @brief Whether all bits are set
          *
          * @see @ref none(), @ref any(), @ref operator bool()
          */
-        bool all() const;
+        MAGNUM_CONSTEXPR14 bool all() const;
 
         /**
          * @brief Whether no bits are set
@@ -361,7 +362,7 @@ template<std::size_t size> inline bool BitVector<size>::operator==(const BitVect
     return true;
 }
 
-template<std::size_t size> inline bool BitVector<size>::all() const {
+template<std::size_t size> MAGNUM_CONSTEXPR14 inline bool BitVector<size>::all() const {
     /* Check all full segments */
     for(std::size_t i = 0; i != size/8; ++i)
         if(_data[i] != FullSegmentMask) return false;

src/Magnum/Math/Math.h

@@ -116,4 +116,17 @@ namespace Implementation {
 
 }}
 
+// TODO remove this once corrade#152 gets merged
+#if defined __cpp_constexpr && __cpp_constexpr >= 201304 || \
+    defined CORRADE_TARGET_MSVC && _MSC_VER >= 1910 && CORRADE_CXX_STANDARD >= 201402L
+#define MAGNUM_CONSTEXPR14 constexpr
+#else
+#define MAGNUM_CONSTEXPR14
+#endif
+#if defined(__clang__) && __clang_major__ >= 9 || defined(__GNUG__) && __GNUG__ >= 9 || defined(_MSC_VER) && _MSC_VER >= 1931
+#define MAGNUM_CONSTEVAL (__builtin_is_constant_evaluated())
+#elif CORRADE_CXX_STANDARD >= 202002L
+#define MAGNUM_CONSTEVAL (std::is_constant_evaluated())
+#endif
+
 #endif

src/Magnum/Math/Test/CMakeLists.txt

@@ -41,6 +41,13 @@ corrade_add_test(MathVectorTest VectorTest.cpp LIBRARIES MagnumMathTestLib)
 corrade_add_test(MathVector2Test Vector2Test.cpp LIBRARIES MagnumMathTestLib)
 corrade_add_test(MathVector3Test Vector3Test.cpp LIBRARIES MagnumMathTestLib)
 corrade_add_test(MathVector4Test Vector4Test.cpp LIBRARIES MagnumMathTestLib)
+
+foreach(_test VectorTest Vector2Test Vector3Test Vector4Test)
+    corrade_add_test(Cpp14Math${_test} ${_test}.cpp LIBRARIES MagnumMathTestLib)
+    set_target_properties(Cpp14Math${_test} PROPERTIES CORRADE_CXX_STANDARD 14)
+    target_compile_definitions(Cpp14Math${_test} PRIVATE TESTING_CONSTEXPR CORRADE_GRACEFUL_ASSERT)
+endforeach()
+
 corrade_add_test(MathColorTest ColorTest.cpp LIBRARIES MagnumMathTestLib)
 
 corrade_add_test(MathRectangularMatrixTest RectangularMatrixTest.cpp LIBRARIES MagnumMathTestLib)

src/Magnum/Math/Test/Cpp14VectorTest.h

@@ -0,0 +1,14 @@
+#ifndef Magnum_Math_Test_Cpp14Vector
+#define Magnum_Math_Test_Cpp14Vector
+
+#define CE
+#ifdef TESTING_CONSTEXPR
+#if __cpp_constexpr >= 201304
+#undef CE
+#define CE constexpr
+#else
+#define SKIP_TESTING
+#endif
+#endif
+
+#endif

src/Magnum/Math/Test/Vector2Test.cpp

@@ -32,6 +32,8 @@
 #include "Magnum/Math/StrictWeakOrdering.h"
 #include "Magnum/Math/Swizzle.h"
 
+#include "Cpp14VectorTest.h"
+
 struct Vec2 {
     float x, y;
 };
@@ -57,6 +59,7 @@ namespace Test { namespace {
 struct Vector2Test: Corrade::TestSuite::Tester {
     explicit Vector2Test();
 
+#ifndef SKIP_TESTING
     void construct();
     void constructDefault();
     void constructNoInit();
@@ -76,14 +79,24 @@ struct Vector2Test: Corrade::TestSuite::Tester {
 
     void swizzleType();
     void debug();
+#else
+    void skipTesting();
+#endif
 };
 
 typedef Math::Vector3<Int> Vector3i;
 typedef Math::Vector2<Float> Vector2;
 typedef Math::Vector2<Int> Vector2i;
 
 Vector2Test::Vector2Test() {
-    addTests({&Vector2Test::construct,
+#ifndef TESTING_CONSTEXPR
+    setTestName("MathVector2Test");
+#else
+    setTestName("Cpp14MathVector2Test");
+#endif
+    addTests({
+#ifndef SKIP_TESTING
+              &Vector2Test::construct,
               &Vector2Test::constructDefault,
               &Vector2Test::constructNoInit,
               &Vector2Test::constructOneValue,
@@ -101,9 +114,15 @@ Vector2Test::Vector2Test() {
               &Vector2Test::strictWeakOrdering,
 
               &Vector2Test::swizzleType,
-              &Vector2Test::debug});
+              &Vector2Test::debug
+#else
+              &Vector2Test::skipTesting
+#endif
+    });
 }
 
+#ifndef SKIP_TESTING
+
 void Vector2Test::construct() {
     constexpr Vector2 a = {1.5f, 2.5f};
     CORRADE_COMPARE(a, (Vector<2, Float>(1.5f, 2.5f)));
@@ -197,7 +216,7 @@ void Vector2Test::convert() {
 }
 
 void Vector2Test::access() {
-    Vector2 vec(1.0f, -2.0f);
+    CE Vector2 vec(1.0f, -2.0f);
     CORRADE_COMPARE(vec.x(), 1.0f);
     CORRADE_COMPARE(vec.y(), -2.0f);
 
@@ -209,8 +228,8 @@ void Vector2Test::access() {
 }
 
 void Vector2Test::cross() {
-    Vector2i a(1, -1);
-    Vector2i b(4, 3);
+    CE Vector2i a(1, -1);
+    CE Vector2i b(4, 3);
 
     CORRADE_COMPARE(Math::cross(a, b), 7);
     CORRADE_COMPARE(Math::cross<Int>({a, 0}, {b, 0}), Vector3i(0, 0, Math::cross(a, b)));
@@ -268,6 +287,11 @@ void Vector2Test::debug() {
     Debug(&o) << Vector2(0.5f, 15.0f);
     CORRADE_COMPARE(o.str(), "Vector(0.5, 15)\n");
 }
+#else
+void Vector2Test::skipTesting() {
+    CORRADE_SKIP("Relaxed constexpr not supported by the compiler.");
+}
+#endif
 
 }}}}
 

src/Magnum/Math/Test/Vector3Test.cpp

@@ -23,6 +23,8 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+#include "Cpp14VectorTest.h"
+
 #include <sstream>
 #include <Corrade/TestSuite/Tester.h>
 #include <Corrade/Utility/DebugStl.h>
@@ -57,6 +59,7 @@ namespace Test { namespace {
 struct Vector3Test: Corrade::TestSuite::Tester {
     explicit Vector3Test();
 
+#ifndef SKIP_TESTING
     void construct();
     void constructDefault();
     void constructNoInit();
@@ -76,14 +79,24 @@ struct Vector3Test: Corrade::TestSuite::Tester {
 
     void swizzleType();
     void debug();
+#else
+    void skipTesting();
+#endif
 };
 
 typedef Math::Vector3<Float> Vector3;
 typedef Math::Vector3<Int> Vector3i;
 typedef Math::Vector2<Float> Vector2;
 
 Vector3Test::Vector3Test() {
-    addTests({&Vector3Test::construct,
+#ifndef TESTING_CONSTEXPR
+    setTestName("MathVector3Test");
+#else
+    setTestName("Cpp14MathVector3Test");
+#endif
+    addTests({
+#ifndef SKIP_TESTING
+              &Vector3Test::construct,
               &Vector3Test::constructDefault,
               &Vector3Test::constructNoInit,
               &Vector3Test::constructOneValue,
@@ -101,9 +114,13 @@ Vector3Test::Vector3Test() {
               &Vector3Test::strictWeakOrdering,
 
               &Vector3Test::swizzleType,
-              &Vector3Test::debug});
+              &Vector3Test::debug
+#else
+              &Vector3Test::skipTesting
+#endif
+    });
 }
-
+#ifndef SKIP_TESTING
 void Vector3Test::construct() {
     constexpr Vector3 a = {1.0f, 2.5f, -3.0f};
     CORRADE_COMPARE(a, (Vector<3, Float>(1.0f, 2.5f, -3.0f)));
@@ -206,7 +223,7 @@ void Vector3Test::convert() {
 }
 
 void Vector3Test::access() {
-    Vector3 vec(1.0f, -2.0f, 5.0f);
+    CE Vector3 vec(1.0f, -2.0f, 5.0f);
     CORRADE_COMPARE(vec.x(), 1.0f);
     CORRADE_COMPARE(vec.r(), 1.0f);
     CORRADE_COMPARE(vec.y(), -2.0f);
@@ -230,8 +247,8 @@ void Vector3Test::access() {
 }
 
 void Vector3Test::cross() {
-    Vector3i a(1, -1, 1);
-    Vector3i b(4, 3, 7);
+    CE Vector3i a(1, -1, 1);
+    CE Vector3i b(4, 3, 7);
 
     CORRADE_COMPARE(Math::cross(a, b), Vector3i(-10, -3, 7));
 }
@@ -255,7 +272,7 @@ void Vector3Test::scales() {
 }
 
 void Vector3Test::twoComponent() {
-    Vector3 a(1.0f, 2.0f, 3.0f);
+    CE Vector3 a(1.0f, 2.0f, 3.0f);
     CORRADE_COMPARE(a.xy(), Vector2(1.0f, 2.0f));
 
     constexpr Vector3 b(1.0f, 2.0f, 3.0f);
@@ -292,7 +309,11 @@ void Vector3Test::debug() {
     Debug(&o) << Vector3(0.5f, 15.0f, 1.0f);
     CORRADE_COMPARE(o.str(), "Vector(0.5, 15, 1)\n");
 }
-
+#else
+void Vector3Test::skipTesting() {
+    CORRADE_SKIP("Relaxed constexpr not supported by the compiler.");
+}
+#endif
 }}}}
 
 CORRADE_TEST_MAIN(Magnum::Math::Test::Vector3Test)