Enabled bin_to_hex utest for stdformat, and fixed std::formatter

.github/workflows/macos.yml

@@ -9,6 +9,15 @@ jobs:
   build:
     runs-on: macOS-latest
     name: "macOS Clang (C++11, Release)"
+    strategy:
+      fail-fast: true
+      matrix:
+        config:
+            - USE_STD_FORMAT: 'ON'
+              BUILD_EXAMPLE: 'OFF'
+            - USE_STD_FORMAT: 'OFF'
+              BUILD_EXAMPLE: 'ON'
+              
     steps:
       - uses: actions/checkout@v4
       - name: Build
@@ -17,12 +26,13 @@ jobs:
           cmake .. \
             -DCMAKE_BUILD_TYPE=Release \
             -DCMAKE_CXX_STANDARD=11 \
-            -DSPDLOG_BUILD_EXAMPLE=ON \
-            -DSPDLOG_BUILD_EXAMPLE_HO=ON \
+            -DSPDLOG_BUILD_EXAMPLE=${{ matrix.config.BUILD_EXAMPLE }} `
+            -DSPDLOG_BUILD_EXAMPLE_HO=${{ matrix.config.BUILD_EXAMPLE }} `
             -DSPDLOG_BUILD_WARNINGS=ON \
             -DSPDLOG_BUILD_BENCH=OFF \
             -DSPDLOG_BUILD_TESTS=ON \
             -DSPDLOG_BUILD_TESTS_HO=OFF \
+            -DSPDLOG_USE_STD_FORMAT=${{ matrix.config.USE_STD_FORMAT }} `
             -DSPDLOG_SANITIZE_ADDRESS=OFF
           make -j 4
           ctest -j 4 --output-on-failure

include/spdlog/fmt/bin_to_hex.h

@@ -102,7 +102,7 @@ namespace
 
 template <typename T>
 struct formatter<spdlog::details::dump_info<T>, char> {
-    const char delimiter = ' ';
+    char delimiter = ' ';
     bool put_newlines = true;
     bool put_delimiters = true;
     bool use_uppercase = false;

tests/CMakeLists.txt

@@ -48,7 +48,8 @@ set(SPDLOG_UTESTS_SOURCES
     test_cfg.cpp
     test_time_point.cpp
     test_stopwatch.cpp
-    test_circular_q.cpp)
+    test_circular_q.cpp
+    test_bin_to_hex.cpp)
 
 if(NOT SPDLOG_NO_EXCEPTIONS)
     list(APPEND SPDLOG_UTESTS_SOURCES test_errors.cpp)
@@ -58,10 +59,6 @@ if(systemd_FOUND)
     list(APPEND SPDLOG_UTESTS_SOURCES test_systemd.cpp)
 endif()
 
-if(NOT SPDLOG_USE_STD_FORMAT)
-    list(APPEND SPDLOG_UTESTS_SOURCES test_bin_to_hex.cpp)
-endif()
-
 enable_testing()
 
 function(spdlog_prepare_test test_target spdlog_lib)