Math: support packed debug output for Range.

src/Magnum/Math/Range.h

@@ -793,14 +793,17 @@ template<UnsignedInt dimensions, class T> inline bool intersects(const Range<dim
 #ifndef CORRADE_SINGLES_NO_DEBUG
 /** @debugoperator{Range} */
 template<UnsignedInt dimensions, class T> Debug& operator<<(Debug& debug, const Range<dimensions, T>& value) {
-    debug << "Range({" << Debug::nospace << Vector<dimensions, T>{value.min()}[0];
+    /** @todo might make sense to propagate the flags also, for hex value
+        printing etc */
+    const bool packed = debug.immediateFlags() >= Debug::Flag::Packed;
+    debug << (packed ? "{{" : "Range({") << Debug::nospace << Vector<dimensions, T>{value.min()}[0];
     for(UnsignedInt i = 1; i != dimensions; ++i)
         debug << Debug::nospace << "," << Vector<dimensions, T>{value.min()}[i];
     debug << Debug::nospace << "}, {"
           << Debug::nospace << Vector<dimensions, T>{value.max()}[0];
     for(UnsignedInt i = 1; i != dimensions; ++i)
         debug << Debug::nospace << "," << Vector<dimensions, T>{value.max()}[i];
-    return debug << Debug::nospace << "})";
+    return debug << Debug::nospace << (packed ? "}}" : "})");
 }
 
 /* Explicit instantiation for commonly used types */

src/Magnum/Math/Test/RangeTest.cpp

@@ -144,6 +144,7 @@ struct RangeTest: TestSuite::Tester {
     void subclass();
 
     void debug();
+    void debugPacked();
 };
 
 using Magnum::Range1D;
@@ -192,7 +193,8 @@ RangeTest::RangeTest() {
               &RangeTest::subclassTypes,
               &RangeTest::subclass,
 
-              &RangeTest::debug});
+              &RangeTest::debug,
+              &RangeTest::debugPacked});
 }
 
 void RangeTest::construct() {
@@ -966,6 +968,13 @@ void RangeTest::debug() {
     CORRADE_COMPARE(o.str(), "Range({34, 23}, {47, 30})\n");
 }
 
+void RangeTest::debugPacked() {
+    std::ostringstream out;
+    /* Second is not packed, the first should not make any flags persistent */
+    Debug{&out} << Debug::packed << Range2Di{{34, 23}, {47, 30}} << Range2Di{};
+    CORRADE_COMPARE(out.str(), "{{34, 23}, {47, 30}} Range({0, 0}, {0, 0})\n");
+}
+
 }}}}
 
 CORRADE_TEST_MAIN(Magnum::Math::Test::RangeTest)