Rework internals of CATCH_REGISTER_ENUM

The old internals reached into the global hub to stash the allocation(s)
for enum value -> string value there, then kept around a potentially
invalid (in case the hub was cleaned up) reference into it, going through
whole bunch of virtual dispatch in the process.

The new internals just store the data in a static variable inside the
`StringMaker` specialization. This avoids potential lifetime issues,
avoids all virtual dispatch and (almost) reduces the include bloat in
the main header path.

The reason for (almost) there is that for full include correctness,
`EnumInfo` needs `<utility>` include for `std::pair`. However, this brings
in things like `std::relops`, because the std headers in C++ are dumb.
As this was not included before, and instead we relied on `std::pair`
existing in an internal stdlib header that we transitively included, the
full include size ends up bigger than before.

1 files changed, 72 insertions, 15 deletions

diff --git a/tests/SelfTest/UsageTests/EnumToString.tests.cpp b/tests/SelfTest/UsageTests/EnumToString.tests.cpp
index 268a7cad..bacd5608 100644
--- a/tests/SelfTest/UsageTests/EnumToString.tests.cpp
+++ b/tests/SelfTest/UsageTests/EnumToString.tests.cpp
@@ -7,8 +7,60 @@
 // SPDX-License-Identifier: BSL-1.0
 
 #include <catch2/catch_test_macros.hpp>
-#include <catch2/internal/catch_enum_values_registry.hpp>
+#include <catch2/internal/catch_enum_info.hpp>
+#include <catch2/matchers/catch_matchers_vector.hpp>
 
+namespace Bikeshed {
+    enum class Colours { Red, Green, Blue };
+}
+
+// Important!: This macro must appear at top level scope - not inside a namespace
+// You can fully qualify the names, or use a using if you prefer
+CATCH_REGISTER_ENUM( Bikeshed::Colours,
+                     Bikeshed::Colours::Red,
+                     Bikeshed::Colours::Green,
+                     Bikeshed::Colours::Blue )
+
+TEST_CASE( "Enums in namespaces can quickly have stringification enabled using CATCH_REGISTER_ENUM" ) {
+    using Catch::Detail::stringify;
+    REQUIRE( stringify( Bikeshed::Colours::Red ) == "Red" );
+    REQUIRE( stringify( Bikeshed::Colours::Blue ) == "Blue" );
+}
+
+TEST_CASE( "parseEnums", "[Strings][enums]" ) {
+    using namespace Catch::Matchers;
+    using Catch::Detail::parseEnums;
+
+    SECTION( "No enums" )
+        CHECK_THAT( parseEnums( "" ), Equals( std::vector<Catch::StringRef>{} ) );
+
+    SECTION( "One enum value" ) {
+        CHECK_THAT( parseEnums( "ClassName::EnumName::Value1" ),
+                Equals(std::vector<Catch::StringRef>{"Value1"} ) );
+        CHECK_THAT( parseEnums( "Value1" ),
+                Equals( std::vector<Catch::StringRef>{"Value1"} ) );
+        CHECK_THAT( parseEnums( "EnumName::Value1" ),
+                Equals(std::vector<Catch::StringRef>{"Value1"} ) );
+    }
+
+    SECTION( "Multiple enum values" ) {
+        CHECK_THAT( parseEnums( "ClassName::EnumName::Value1, ClassName::EnumName::Value2" ),
+                    Equals( std::vector<Catch::StringRef>{"Value1", "Value2"} ) );
+        CHECK_THAT( parseEnums( "ClassName::EnumName::Value1, ClassName::EnumName::Value2, ClassName::EnumName::Value3" ),
+                    Equals( std::vector<Catch::StringRef>{"Value1", "Value2", "Value3"} ) );
+        CHECK_THAT( parseEnums( "ClassName::EnumName::Value1,ClassName::EnumName::Value2 , ClassName::EnumName::Value3" ),
+                    Equals( std::vector<Catch::StringRef>{"Value1", "Value2", "Value3"} ) );
+    }
+}
+
+TEST_CASE( "Directly creating an EnumInfo" ) {
+    using namespace Catch::Detail;
+    auto enumInfo = makeEnumInfo( "EnumName", "EnumName::Value1, EnumName::Value2", {0, 1} );
+
+    CHECK( enumInfo.lookup(0) == "Value1" );
+    CHECK( enumInfo.lookup(1) == "Value2" );
+    CHECK( enumInfo.lookup(3) == "{** unexpected enum value **}" );
+}
 
 namespace {
 // Enum without user-provided stream operator
@@ -90,19 +142,24 @@ TEST_CASE( "Enums can quickly have stringification enabled using CATCH_REGISTER_
     REQUIRE( stringify( ec3 ) == "Value2" );
 }
 
-namespace Bikeshed {
-    enum class Colours { Red, Green, Blue };
-}
-
-// Important!: This macro must appear at top level scope - not inside a namespace
-// You can fully qualify the names, or use a using if you prefer
-CATCH_REGISTER_ENUM( Bikeshed::Colours,
-                     Bikeshed::Colours::Red,
-                     Bikeshed::Colours::Green,
-                     Bikeshed::Colours::Blue )
-
-TEST_CASE( "Enums in namespaces can quickly have stringification enabled using CATCH_REGISTER_ENUM" ) {
+enum class LargeEnum : std::int64_t {
+    Flag1 = 0x01,
+    Flag2 = 0x02,
+    Flag3 = 0x04,
+    Flag4 = 0x08,
+    Flag5 = 0x10,
+};
+
+CATCH_REGISTER_ENUM( LargeEnum,
+                     LargeEnum::Flag1,
+                     LargeEnum::Flag2,
+                     LargeEnum::Flag3,
+                     LargeEnum::Flag4,
+                     LargeEnum::Flag5 )
+
+TEST_CASE( "Enum backed by larger underlying type", "[enum][toString]" ) {
     using Catch::Detail::stringify;
-    REQUIRE( stringify( Bikeshed::Colours::Red ) == "Red" );
-    REQUIRE( stringify( Bikeshed::Colours::Blue ) == "Blue" );
+    REQUIRE( stringify( LargeEnum::Flag1 ) == "Flag1" );
+    REQUIRE( stringify( LargeEnum::Flag2 ) == "Flag2" );
+    REQUIRE( stringify( LargeEnum::Flag5 ) == "Flag5" );
 }