cmMakefile: Add helper to initialize CMAKE_CONFIGURATION_TYPES

Factor out duplicate code from the Ninja Multi-Config, Visual Studio,
and Xcode generators.

Source/cmGlobalNinjaGenerator.cxx

@@ -920,14 +920,7 @@ void cmGlobalNinjaGenerator::EnableLanguage(
   std::vector<std::string> const& langs, cmMakefile* mf, bool optional)
 {
   if (this->IsMultiConfig()) {
-    if (!mf->GetDefinition("CMAKE_CONFIGURATION_TYPES")) {
-      mf->AddCacheDefinition(
-        "CMAKE_CONFIGURATION_TYPES", "Debug;Release;RelWithDebInfo",
-        "Semicolon separated list of supported configuration types, only "
-        "supports Debug, Release, MinSizeRel, and RelWithDebInfo, anything "
-        "else will be ignored",
-        cmStateEnums::STRING);
-    }
+    mf->InitCMAKE_CONFIGURATION_TYPES("Debug;Release;RelWithDebInfo");
   }
 
   this->cmGlobalGenerator::EnableLanguage(langs, mf, optional);

Source/cmGlobalVisualStudio7Generator.cxx

@@ -107,14 +107,7 @@ void cmGlobalVisualStudio7Generator::EnableLanguage(
 {
   mf->AddDefinition("CMAKE_GENERATOR_RC", "rc");
   mf->AddDefinition("CMAKE_GENERATOR_NO_COMPILER_ENV", "1");
-  if (!mf->GetDefinition("CMAKE_CONFIGURATION_TYPES")) {
-    mf->AddCacheDefinition(
-      "CMAKE_CONFIGURATION_TYPES", "Debug;Release;MinSizeRel;RelWithDebInfo",
-      "Semicolon separated list of supported configuration types, "
-      "only supports Debug, Release, MinSizeRel, and RelWithDebInfo, "
-      "anything else will be ignored.",
-      cmStateEnums::STRING);
-  }
+  mf->InitCMAKE_CONFIGURATION_TYPES("Debug;Release;MinSizeRel;RelWithDebInfo");
 
   // Create list of configurations requested by user's cache, if any.
   this->cmGlobalVisualStudioGenerator::EnableLanguage(lang, mf, optional);

Source/cmGlobalXCodeGenerator.cxx

@@ -431,14 +431,7 @@ void cmGlobalXCodeGenerator::EnableLanguage(
 {
   mf->AddDefinition("XCODE", "1");
   mf->AddDefinition("XCODE_VERSION", this->VersionString);
-  if (!mf->GetDefinition("CMAKE_CONFIGURATION_TYPES")) {
-    mf->AddCacheDefinition(
-      "CMAKE_CONFIGURATION_TYPES", "Debug;Release;MinSizeRel;RelWithDebInfo",
-      "Semicolon separated list of supported configuration types, "
-      "only supports Debug, Release, MinSizeRel, and RelWithDebInfo, "
-      "anything else will be ignored.",
-      cmStateEnums::STRING);
-  }
+  mf->InitCMAKE_CONFIGURATION_TYPES("Debug;Release;MinSizeRel;RelWithDebInfo");
   mf->AddDefinition("CMAKE_GENERATOR_NO_COMPILER_ENV", "1");
   this->cmGlobalGenerator::EnableLanguage(lang, mf, optional);
   this->ComputeArchitectures(mf);

Source/cmMakefile.cxx

@@ -3182,6 +3182,19 @@ void cmMakefile::RemoveVariablesInString(std::string& source,
   }
 }
 
+void cmMakefile::InitCMAKE_CONFIGURATION_TYPES(std::string const& genDefault)
+{
+  if (this->GetDefinition("CMAKE_CONFIGURATION_TYPES")) {
+    return;
+  }
+  this->AddCacheDefinition(
+    "CMAKE_CONFIGURATION_TYPES", genDefault,
+    "Semicolon separated list of supported configuration types, "
+    "only supports Debug, Release, MinSizeRel, and RelWithDebInfo, "
+    "anything else will be ignored.",
+    cmStateEnums::STRING);
+}
+
 std::string cmMakefile::GetDefaultConfiguration() const
 {
   if (this->GetGlobalGenerator()->IsMultiConfig()) {

Source/cmMakefile.h

@@ -310,6 +310,8 @@ public:
    */
   void SetProjectName(std::string const& name);
 
+  void InitCMAKE_CONFIGURATION_TYPES(std::string const& genDefault);
+
   /* Get the default configuration */
   std::string GetDefaultConfiguration() const;