VS: Model a default target framework

Add fields to the VS generator to select a target framework.
Migrate the existing default for VS 12 .NET CF for Windows CE.

Report the values in `CMAKE_VS_*` variables and use them for
the CSharp compiler id project too.

Issue: #22849

Help/manual/cmake-variables.7.rst

@@ -125,6 +125,9 @@ Variables that Provide Information
    /variable/CMAKE_VS_PLATFORM_TOOLSET_CUDA_CUSTOM_DIR
    /variable/CMAKE_VS_PLATFORM_TOOLSET_HOST_ARCHITECTURE
    /variable/CMAKE_VS_PLATFORM_TOOLSET_VERSION
+   /variable/CMAKE_VS_TARGET_FRAMEWORK_VERSION
+   /variable/CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER
+   /variable/CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION
    /variable/CMAKE_VS_WINDOWS_TARGET_PLATFORM_VERSION
    /variable/CMAKE_VS_WINDOWS_TARGET_PLATFORM_VERSION_MAXIMUM
    /variable/CMAKE_XCODE_BUILD_SYSTEM

Help/variable/CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER.rst

@@ -0,0 +1,13 @@
+CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER
+------------------------------------
+
+.. versionadded:: 3.22
+
+Visual Studio target framework identifier.
+
+In some cases, the :ref:`Visual Studio Generators` may use an explicit value
+for the MSBuild ``TargetFrameworkIdentifier`` setting in ``.csproj`` files.
+CMake provides the chosen value in this variable.
+
+See also :variable:`CMAKE_VS_TARGET_FRAMEWORK_VERSION` and
+:variable:`CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION`.

Help/variable/CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION.rst

@@ -0,0 +1,13 @@
+CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION
+-----------------------------------------
+
+.. versionadded:: 3.22
+
+Visual Studio target framework targets version.
+
+In some cases, the :ref:`Visual Studio Generators` may use an explicit value
+for the MSBuild ``TargetFrameworkTargetsVersion`` setting in ``.csproj`` files.
+CMake provides the chosen value in this variable.
+
+See also :variable:`CMAKE_VS_TARGET_FRAMEWORK_VERSION` and
+:variable:`CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER`.

Help/variable/CMAKE_VS_TARGET_FRAMEWORK_VERSION.rst

@@ -0,0 +1,17 @@
+CMAKE_VS_TARGET_FRAMEWORK_VERSION
+---------------------------------
+
+.. versionadded:: 3.22
+
+Visual Studio target framework version.
+
+In some cases, the :ref:`Visual Studio Generators` may use an explicit value
+for the MSBuild ``TargetFrameworkVersion`` setting in ``.csproj`` files.
+CMake provides the chosen value in this variable.
+
+See the :variable:`CMAKE_DOTNET_TARGET_FRAMEWORK_VERSION` variable
+and :prop_tgt:`DOTNET_TARGET_FRAMEWORK_VERSION` target property to
+specify custom ``TargetFrameworkVersion`` values for project targets.
+
+See also :variable:`CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER` and
+:variable:`CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION`.

Modules/CMakeDetermineCompilerId.cmake

@@ -421,6 +421,15 @@ Id flags: ${testflags} ${CMAKE_${lang}_COMPILER_ID_FLAGS_ALWAYS}
     if(CMAKE_VS_PLATFORM_TOOLSET_VCTARGETS_CUSTOM_DIR)
       set(id_ToolsetVCTargetsDir "<VCTargetsPath>${CMAKE_VS_PLATFORM_TOOLSET_VCTARGETS_CUSTOM_DIR}</VCTargetsPath>")
     endif()
+    if(CMAKE_VS_TARGET_FRAMEWORK_VERSION)
+      set(id_TargetFrameworkVersion "<TargetFrameworkVersion>${CMAKE_VS_TARGET_FRAMEWORK_VERSION}</TargetFrameworkVersion>")
+    endif()
+    if(CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER)
+      set(id_TargetFrameworkIdentifier "<TargetFrameworkIdentifier>${CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER}</TargetFrameworkIdentifier>")
+    endif()
+    if(CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION)
+      set(id_TargetFrameworkTargetsVersion "<TargetFrameworkTargetsVersion>${CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION}</TargetFrameworkTargetsVersion>")
+    endif()
     set(id_CustomGlobals "")
     foreach(pair IN LISTS CMAKE_VS_GLOBALS)
       if("${pair}" MATCHES "([^=]+)=(.*)$")

Modules/CompilerId/VS-10.csproj.in

@@ -6,6 +6,9 @@
     <Keyword>Win32Proj</Keyword>
     @id_system@
     @id_system_version@
+    @id_TargetFrameworkVersion@
+    @id_TargetFrameworkIdentifier@
+    @id_TargetFrameworkTargetsVersion@
     @id_WindowsTargetPlatformVersion@
     @id_WindowsSDKDesktopARMSupport@
   </PropertyGroup>

Source/cmGlobalVisualStudio10Generator.cxx

@@ -580,6 +580,13 @@ bool cmGlobalVisualStudio10Generator::InitializeWindowsCE(cmMakefile* mf)
 
   this->DefaultPlatformToolset = this->SelectWindowsCEToolset();
 
+  if (this->GetVersion() == cmGlobalVisualStudioGenerator::VS12) {
+    // VS 12 .NET CF defaults to .NET framework 3.9 for Windows CE.
+    this->DefaultTargetFrameworkVersion = "v3.9";
+    this->DefaultTargetFrameworkIdentifier = "WindowsEmbeddedCompact";
+    this->DefaultTargetFrameworkTargetsVersion = "v8.0";
+  }
+
   return true;
 }
 

Source/cmGlobalVisualStudio8Generator.cxx

@@ -76,12 +76,48 @@ bool cmGlobalVisualStudio8Generator::SetGeneratorPlatform(std::string const& p,
 
   this->GeneratorPlatform = p;
 
+  // FIXME: Add CMAKE_GENERATOR_PLATFORM field to set the framework.
+  // For now, just report the generator's default, if any.
+  if (cm::optional<std::string> const& targetFrameworkVersion =
+        this->GetTargetFrameworkVersion()) {
+    mf->AddDefinition("CMAKE_VS_TARGET_FRAMEWORK_VERSION",
+                      *targetFrameworkVersion);
+  }
+  if (cm::optional<std::string> const& targetFrameworkIdentifier =
+        this->GetTargetFrameworkIdentifier()) {
+    mf->AddDefinition("CMAKE_VS_TARGET_FRAMEWORK_IDENTIFIER",
+                      *targetFrameworkIdentifier);
+  }
+  if (cm::optional<std::string> const& targetFrameworkTargetsVersion =
+        this->GetTargetFrameworkTargetsVersion()) {
+    mf->AddDefinition("CMAKE_VS_TARGET_FRAMEWORK_TARGETS_VERSION",
+                      *targetFrameworkTargetsVersion);
+  }
+
   // The generator name does not contain the platform name, and so supports
   // explicit platform specification.  We handled that above, so pass an
   // empty platform name to our base class implementation so it does not error.
   return this->cmGlobalVisualStudio7Generator::SetGeneratorPlatform("", mf);
 }
 
+cm::optional<std::string> const&
+cmGlobalVisualStudio8Generator::GetTargetFrameworkVersion() const
+{
+  return this->DefaultTargetFrameworkVersion;
+}
+
+cm::optional<std::string> const&
+cmGlobalVisualStudio8Generator::GetTargetFrameworkIdentifier() const
+{
+  return this->DefaultTargetFrameworkIdentifier;
+}
+
+cm::optional<std::string> const&
+cmGlobalVisualStudio8Generator::GetTargetFrameworkTargetsVersion() const
+{
+  return this->DefaultTargetFrameworkTargetsVersion;
+}
+
 std::string cmGlobalVisualStudio8Generator::GetGenerateStampList()
 {
   return "generate.stamp.list";

Source/cmGlobalVisualStudio8Generator.h

@@ -2,6 +2,8 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #pragma once
 
+#include <cm/optional>
+
 #include "cmGlobalVisualStudio71Generator.h"
 
 /** \class cmGlobalVisualStudio8Generator
@@ -24,6 +26,10 @@ public:
 
   bool SetGeneratorPlatform(std::string const& p, cmMakefile* mf) override;
 
+  cm::optional<std::string> const& GetTargetFrameworkVersion() const;
+  cm::optional<std::string> const& GetTargetFrameworkIdentifier() const;
+  cm::optional<std::string> const& GetTargetFrameworkTargetsVersion() const;
+
   /**
    * Override Configure and Generate to add the build-system check
    * target.
@@ -76,4 +82,8 @@ protected:
 
   std::string Name;
   std::string WindowsCEVersion;
+
+  cm::optional<std::string> DefaultTargetFrameworkVersion;
+  cm::optional<std::string> DefaultTargetFrameworkIdentifier;
+  cm::optional<std::string> DefaultTargetFrameworkTargetsVersion;
 };

Source/cmVisualStudio10TargetGenerator.cxx

@@ -507,12 +507,9 @@ void cmVisualStudio10TargetGenerator::Generate()
         } else if (cmValue tfVer = this->GeneratorTarget->GetProperty(
                      "DOTNET_TARGET_FRAMEWORK_VERSION")) {
           targetFrameworkVersion = *tfVer;
-        } else if (this->ProjectType == csproj &&
-                   this->GlobalGenerator->TargetsWindowsCE() &&
-                   this->GlobalGenerator->GetVersion() ==
-                     cmGlobalVisualStudioGenerator::VS12) {
-          // VS12 .NETCF default to .NET framework 3.9
-          targetFrameworkVersion = "v3.9";
+        } else if (this->ProjectType == csproj) {
+          targetFrameworkVersion =
+            this->GlobalGenerator->GetTargetFrameworkVersion();
         }
         if (this->ProjectType == vcxproj &&
             this->GlobalGenerator->TargetsWindowsCE()) {
@@ -527,16 +524,20 @@ void cmVisualStudio10TargetGenerator::Generate()
             if (cmValue tfId = this->GeneratorTarget->GetProperty(
                   "VS_TARGET_FRAMEWORK_IDENTIFIER")) {
               targetFrameworkIdentifier = *tfId;
-            } else {
-              targetFrameworkIdentifier = "WindowsEmbeddedCompact";
             }
             if (cmValue tfTargetsVer = this->GeneratorTarget->GetProperty(
                   "VS_TARGET_FRAMEWORKS_TARGET_VERSION")) {
               targetFrameworkTargetsVersion = *tfTargetsVer;
-            } else {
-              targetFrameworkTargetsVersion = "v8.0";
             }
           }
+          if (!targetFrameworkIdentifier) {
+            targetFrameworkIdentifier =
+              this->GlobalGenerator->GetTargetFrameworkIdentifier();
+          }
+          if (!targetFrameworkTargetsVersion) {
+            targetFrameworkTargetsVersion =
+              this->GlobalGenerator->GetTargetFrameworkTargetsVersion();
+          }
         }
         if (targetFramework) {
           if (targetFramework->find(';') != std::string::npos) {