Unity: Refactor implementation to make it easier to extend

Source/cmLocalGenerator.cxx

@@ -2756,6 +2756,73 @@ void cmLocalGenerator::AddPchDependencies(cmGeneratorTarget* target)
   }
 }
 
+namespace {
+
+inline void RegisterUnitySources(cmGeneratorTarget* target, cmSourceFile* sf,
+                                 std::string const& filename)
+{
+  target->AddSourceFileToUnityBatch(sf->ResolveFullPath());
+  sf->SetProperty("UNITY_SOURCE_FILE", filename.c_str());
+}
+
+inline void IncludeFileInUnitySources(cmGeneratedFileStream& unity_file,
+                                      std::string const& sf_full_path,
+                                      cmProp beforeInclude,
+                                      cmProp afterInclude)
+{
+  if (beforeInclude) {
+    unity_file << *beforeInclude << "\n";
+  }
+
+  unity_file << "#include \"" << sf_full_path << "\"\n";
+
+  if (afterInclude) {
+    unity_file << *afterInclude << "\n";
+  }
+}
+
+std::vector<std::string> AddUnityFilesModeAuto(
+  cmGeneratorTarget* target, std::string const& lang,
+  std::vector<cmSourceFile*> const& filtered_sources, cmProp beforeInclude,
+  cmProp afterInclude, std::string const& filename_base, size_t batchSize)
+{
+  if (batchSize == 0) {
+    batchSize = filtered_sources.size();
+  }
+
+  std::vector<std::string> unity_files;
+  for (size_t itemsLeft = filtered_sources.size(), chunk, batch = 0;
+       itemsLeft > 0; itemsLeft -= chunk, ++batch) {
+
+    chunk = std::min(itemsLeft, batchSize);
+
+    std::string filename = cmStrCat(filename_base, "unity_", batch,
+                                    (lang == "C") ? "_c.c" : "_cxx.cxx");
+
+    const std::string filename_tmp = cmStrCat(filename, ".tmp");
+    {
+      size_t begin = batch * batchSize;
+      size_t end = begin + chunk;
+
+      cmGeneratedFileStream file(
+        filename_tmp, false,
+        target->GetGlobalGenerator()->GetMakefileEncoding());
+      file << "/* generated by CMake */\n\n";
+
+      for (; begin != end; ++begin) {
+        cmSourceFile* sf = filtered_sources[begin];
+        RegisterUnitySources(target, sf, filename);
+        IncludeFileInUnitySources(file, sf->ResolveFullPath(), beforeInclude,
+                                  afterInclude);
+      }
+    }
+    cmSystemTools::MoveFileIfDifferent(filename_tmp, filename);
+    unity_files.emplace_back(std::move(filename));
+  }
+  return unity_files;
+}
+}
+
 void cmLocalGenerator::AddUnityBuild(cmGeneratorTarget* target)
 {
   if (!target->GetPropertyAsBool("UNITY_BUILD")) {
@@ -2798,53 +2865,15 @@ void cmLocalGenerator::AddUnityBuild(cmGeneratorTarget* target)
                      !sf->GetProperty("INCLUDE_DIRECTORIES");
                  });
 
-    size_t batchSize = unityBatchSize;
-    if (unityBatchSize == 0) {
-      batchSize = filtered_sources.size();
-    }
-
-    for (size_t itemsLeft = filtered_sources.size(), chunk, batch = 0;
-         itemsLeft > 0; itemsLeft -= chunk, ++batch) {
-
-      chunk = std::min(itemsLeft, batchSize);
-
-      std::string filename = cmStrCat(filename_base, "unity_", batch,
-                                      (lang == "C") ? "_c.c" : "_cxx.cxx");
-
-      const std::string filename_tmp = cmStrCat(filename, ".tmp");
-      {
-        size_t begin = batch * batchSize;
-        size_t end = begin + chunk;
-
-        cmGeneratedFileStream file(
-          filename_tmp, false,
-          this->GetGlobalGenerator()->GetMakefileEncoding());
-        file << "/* generated by CMake */\n\n";
-
-        for (; begin != end; ++begin) {
-          cmSourceFile* sf = filtered_sources[begin];
-
-          target->AddSourceFileToUnityBatch(sf->ResolveFullPath());
-          sf->SetProperty("UNITY_SOURCE_FILE", filename.c_str());
-
-          if (beforeInclude) {
-            file << *beforeInclude << "\n";
-          }
-
-          file << "#include \"" << sf->ResolveFullPath() << "\"\n";
-
-          if (afterInclude) {
-            file << *afterInclude << "\n";
-          }
-        }
-      }
-      cmSystemTools::MoveFileIfDifferent(filename_tmp, filename);
-
-      target->AddSource(filename, true);
+    std::vector<std::string> unity_files =
+      AddUnityFilesModeAuto(target, lang, filtered_sources, beforeInclude,
+                            afterInclude, filename_base, unityBatchSize);
 
-      auto unity = this->Makefile->GetOrCreateSource(filename);
+    for (auto const& file : unity_files) {
+      auto unity = this->GetMakefile()->GetOrCreateSource(file);
+      target->AddSource(file, true);
       unity->SetProperty("SKIP_UNITY_BUILD_INCLUSION", "ON");
-      unity->SetProperty("UNITY_SOURCE_FILE", filename.c_str());
+      unity->SetProperty("UNITY_SOURCE_FILE", file.c_str());
     }
   }
 }