Unity: Enable UNITY_BUILD for OBJC and OBJCXX files

10 files changed, 145 insertions, 9 deletions

diff --git a/Help/prop_tgt/UNITY_BUILD.rst b/Help/prop_tgt/UNITY_BUILD.rst
index f827a20..52f4714 100644
--- a/Help/prop_tgt/UNITY_BUILD.rst
+++ b/Help/prop_tgt/UNITY_BUILD.rst
@@ -30,11 +30,23 @@ values:
 If no explicit :prop_tgt:`UNITY_BUILD_MODE` has been specified, CMake will
 default to ``BATCH``.
 
-Unity builds are not currently supported for all languages.  CMake version
-|release| supports combining ``C`` and ``CXX`` source files.  For targets that
-mix source files from more than one language, CMake will separate the languages
-such that each generated unity source file only contains sources for a single
-language.
+Unity builds are supported for the following languages:
+
+``C``
+  .. versionadded:: 3.16
+
+``CXX``
+  .. versionadded:: 3.16
+
+``OBJC``
+  .. versionadded:: 3.29
+
+``OBJCXX``
+  .. versionadded:: 3.29
+
+For targets that mix source files from more than one language, CMake
+separates the languages such that each generated unity source file only
+contains sources for a single language.
 
 This property is initialized by the value of the :variable:`CMAKE_UNITY_BUILD`
 variable when a target is created.
diff --git a/Help/release/dev/unity-build-objc.rst b/Help/release/dev/unity-build-objc.rst
new file mode 100644
index 0000000..ce6460b
--- /dev/null
+++ b/Help/release/dev/unity-build-objc.rst
@@ -0,0 +1,5 @@
+unity-build-objc
+----------------
+
+* The :prop_tgt:`UNITY_BUILD` target property now supports the
+  Objective C (``OBJC``) and Objective C++ (``OBJCXX``) languages.
diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index 76e36ab..be18c29 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -3063,8 +3063,17 @@ cmLocalGenerator::AddUnityFilesModeAuto(
 
     chunk = std::min(itemsLeft, batchSize);
 
-    std::string filename = cmStrCat(filename_base, "unity_", batch,
-                                    (lang == "C") ? "_c.c" : "_cxx.cxx");
+    std::string extension;
+    if (lang == "C") {
+      extension = "_c.c";
+    } else if (lang == "CXX") {
+      extension = "_cxx.cxx";
+    } else if (lang == "OBJC") {
+      extension = "_m.m";
+    } else if (lang == "OBJCXX") {
+      extension = "_mm.mm";
+    }
+    std::string filename = cmStrCat(filename_base, "unity_", batch, extension);
     auto const begin = filtered_sources.begin() + batch * batchSize;
     auto const end = begin + chunk;
     unity_files.emplace_back(this->WriteUnitySource(
@@ -3155,7 +3164,7 @@ void cmLocalGenerator::AddUnityBuild(cmGeneratorTarget* target)
   cmValue afterInclude = target->GetProperty("UNITY_BUILD_CODE_AFTER_INCLUDE");
   cmValue unityMode = target->GetProperty("UNITY_BUILD_MODE");
 
-  for (std::string lang : { "C", "CXX" }) {
+  for (std::string lang : { "C", "CXX", "OBJC", "OBJCXX" }) {
     std::vector<UnityBatchedSource> filtered_sources;
     std::copy_if(unitySources.begin(), unitySources.end(),
                  std::back_inserter(filtered_sources),
diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 5a23b8b..78d4585 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -1064,7 +1064,7 @@ add_RunCMake_test(PrecompileHeaders -DCMAKE_C_COMPILER_ID=${CMAKE_C_COMPILER_ID}
   -DCMAKE_C_SIMULATE_ID=${CMAKE_C_SIMULATE_ID}
   -DCMAKE_C_COMPILER_VERSION=${CMAKE_C_COMPILER_VERSION})
 
-add_RunCMake_test("UnityBuild")
+add_RunCMake_test(UnityBuild -DCMake_TEST_OBJC=${CMake_TEST_OBJC})
 add_RunCMake_test(CMakePresets
   -DPython_EXECUTABLE=${Python_EXECUTABLE}
   -DCMake_TEST_JSON_SCHEMA=${CMake_TEST_JSON_SCHEMA}
diff --git a/Tests/RunCMake/UnityBuild/RunCMakeTest.cmake b/Tests/RunCMake/UnityBuild/RunCMakeTest.cmake
index e3643c0..0ec8c42 100644
--- a/Tests/RunCMake/UnityBuild/RunCMakeTest.cmake
+++ b/Tests/RunCMake/UnityBuild/RunCMakeTest.cmake
@@ -14,6 +14,13 @@ run_cmake(unitybuild_cxx)
 run_cmake(unitybuild_cxx_group)
 run_cmake(unitybuild_c_and_cxx)
 run_cmake(unitybuild_c_and_cxx_group)
+if(CMake_TEST_OBJC)
+  run_cmake(unitybuild_objc)
+  run_cmake(unitybuild_objc_group)
+  run_cmake(unitybuild_objcxx)
+  run_cmake(unitybuild_objcxx_group)
+  run_cmake(unitybuild_c_and_cxx_and_objc_and_objcxx)
+endif()
 run_cmake(unitybuild_batchsize)
 run_cmake(unitybuild_default_batchsize)
 run_cmake(unitybuild_skip)
diff --git a/Tests/RunCMake/UnityBuild/unitybuild_c_and_cxx_and_objc_and_objcxx.cmake b/Tests/RunCMake/UnityBuild/unitybuild_c_and_cxx_and_objc_and_objcxx.cmake
new file mode 100644
index 0000000..096a86b
--- /dev/null
+++ b/Tests/RunCMake/UnityBuild/unitybuild_c_and_cxx_and_objc_and_objcxx.cmake
@@ -0,0 +1,25 @@
+project(unitybuild_c_and_cxx_and_objc_and_objcxx C CXX OBJC OBJCXX)
+
+set(srcs "")
+foreach(s RANGE 1 8)
+  set(src_c "${CMAKE_CURRENT_BINARY_DIR}/s${s}.c")
+  file(WRITE "${src_c}" "int s${s}(void) { return 0; }\n")
+
+  set(src_cxx "${CMAKE_CURRENT_BINARY_DIR}/s${s}.cxx")
+  file(WRITE "${src_cxx}" "int s${s}(void) { return 0; }\n")
+
+  set(src_objc "${CMAKE_CURRENT_BINARY_DIR}/s${s}.m")
+  file(WRITE "${src_objc}" "int s${s}(void) { return 0; }\n")
+
+  set(src_objcxx "${CMAKE_CURRENT_BINARY_DIR}/s${s}.mm")
+  file(WRITE "${src_objcxx}" "int s${s}(void) { return 0; }\n")
+
+  list(APPEND srcs "${src_c}")
+  list(APPEND srcs "${src_cxx}")
+  list(APPEND srcs "${src_objc}")
+  list(APPEND srcs "${src_objcxx}")
+endforeach()
+
+add_library(tgt SHARED ${srcs})
+
+set_target_properties(tgt PROPERTIES UNITY_BUILD ON)
diff --git a/Tests/RunCMake/UnityBuild/unitybuild_objc.cmake b/Tests/RunCMake/UnityBuild/unitybuild_objc.cmake
new file mode 100644
index 0000000..cc88d98
--- /dev/null
+++ b/Tests/RunCMake/UnityBuild/unitybuild_objc.cmake
@@ -0,0 +1,12 @@
+project(unitybuild_objc OBJC)
+
+set(srcs "")
+foreach(s RANGE 1 8)
+  set(src "${CMAKE_CURRENT_BINARY_DIR}/s${s}.m")
+  file(WRITE "${src}" "int s${s}(void) { return 0; }\n")
+  list(APPEND srcs "${src}")
+endforeach()
+
+add_library(tgt SHARED ${srcs})
+
+set_target_properties(tgt PROPERTIES UNITY_BUILD ON)
diff --git a/Tests/RunCMake/UnityBuild/unitybuild_objc_group.cmake b/Tests/RunCMake/UnityBuild/unitybuild_objc_group.cmake
new file mode 100644
index 0000000..384c98a
--- /dev/null
+++ b/Tests/RunCMake/UnityBuild/unitybuild_objc_group.cmake
@@ -0,0 +1,27 @@
+project(unitybuild_objc_group OBJC)
+
+set(srcs "")
+foreach(s RANGE 1 4)
+  set(src "${CMAKE_CURRENT_BINARY_DIR}/s${s}.m")
+  file(WRITE "${src}" "int s${s}(void) { return 0; }\n")
+  list(APPEND srcs "${src}")
+endforeach()
+
+foreach(s RANGE 1 2)
+  set(src "${CMAKE_CURRENT_BINARY_DIR}/odr${s}.m")
+  file(WRITE "${src}" "namespace odr { int s${s}(void) { return 0; } }\n")
+  list(APPEND srcs "${src}")
+endforeach()
+
+add_library(tgt SHARED ${srcs})
+
+set_target_properties(tgt PROPERTIES UNITY_BUILD ON
+                          UNITY_BUILD_MODE GROUP
+                          )
+
+set_source_files_properties(s1.m s2.m odr1.m
+                            PROPERTIES UNITY_GROUP "a"
+                            )
+set_source_files_properties(s3.m s4.m odr2.m
+                            PROPERTIES UNITY_GROUP "b"
+                            )
diff --git a/Tests/RunCMake/UnityBuild/unitybuild_objcxx.cmake b/Tests/RunCMake/UnityBuild/unitybuild_objcxx.cmake
new file mode 100644
index 0000000..fd0f743
--- /dev/null
+++ b/Tests/RunCMake/UnityBuild/unitybuild_objcxx.cmake
@@ -0,0 +1,12 @@
+project(unitybuild_objcxx OBJCXX)
+
+set(srcs "")
+foreach(s RANGE 1 8)
+  set(src "${CMAKE_CURRENT_BINARY_DIR}/s${s}.mm")
+  file(WRITE "${src}" "int s${s}(void) { return 0; }\n")
+  list(APPEND srcs "${src}")
+endforeach()
+
+add_library(tgt SHARED ${srcs})
+
+set_target_properties(tgt PROPERTIES UNITY_BUILD ON)
diff --git a/Tests/RunCMake/UnityBuild/unitybuild_objcxx_group.cmake b/Tests/RunCMake/UnityBuild/unitybuild_objcxx_group.cmake
new file mode 100644
index 0000000..517703e
--- /dev/null
+++ b/Tests/RunCMake/UnityBuild/unitybuild_objcxx_group.cmake
@@ -0,0 +1,27 @@
+project(unitybuild_objcxx_group OBJCXX)
+
+set(srcs "")
+foreach(s RANGE 1 4)
+  set(src "${CMAKE_CURRENT_BINARY_DIR}/s${s}.mm")
+  file(WRITE "${src}" "int s${s}(void) { return 0; }\n")
+  list(APPEND srcs "${src}")
+endforeach()
+
+foreach(s RANGE 1 2)
+  set(src "${CMAKE_CURRENT_BINARY_DIR}/odr${s}.mm")
+  file(WRITE "${src}" "namespace odr { int s${s}(void) { return 0; } }\n")
+  list(APPEND srcs "${src}")
+endforeach()
+
+add_library(tgt SHARED ${srcs})
+
+set_target_properties(tgt PROPERTIES UNITY_BUILD ON
+                          UNITY_BUILD_MODE GROUP
+                          )
+
+set_source_files_properties(s1.mm s2.mm odr1.mm
+                            PROPERTIES UNITY_GROUP "a"
+                            )
+set_source_files_properties(s3.mm s4.mm odr2.mm
+                            PROPERTIES UNITY_GROUP "b"
+                            )