test: Add size optimization test with specific compile definitions

Author: teruyamato0731

test/CMakeLists.txt

@@ -255,3 +255,13 @@ if (FMT_CUDA_TEST)
     add_test(NAME cuda-test COMMAND fmt-in-cuda-test)
   endif ()
 endif ()
+
+add_fmt_test(size-opt-test HEADER_ONLY)
+# Apply size optimization definitions from recipe
+target_compile_definitions(size-opt-test PRIVATE
+  FMT_USE_EXCEPTIONS=0
+  FMT_OS=0
+  FMT_BUILTIN_TYPES=0
+  FMT_OPTIMIZE_SIZE=2
+  FMT_USE_LOCALE=0
+)

test/size-opt-test.cc

@@ -0,0 +1,8 @@
+#include "fmt/format.h"
+#include "gtest/gtest.h"
+
+TEST(SizeOptTest, BasicFormatting) {
+  // Test basic formatting under size-optimized, header-only configuration
+  auto s = fmt::format("size-optimized {}", 42);
+  ASSERT_EQ(s, "size-optimized 42");
+}