VS: Add proj as a project type to VsProjectType

Add `proj` as a project type to VsProjectType so that it can be consumed
by `ZERO_CHECK` target. This commit adds the type and cleans up the code
that needs to treat `proj` and `csproj` in the same fashion. Next commit
will make changes to add `ZERO_CHECK.proj`.

Source/cmLocalVisualStudioGenerator.cxx

@@ -252,7 +252,7 @@ std::string cmLocalVisualStudioGenerator::FinishConstructScript(
   // Store the script in a string.
   std::string script;
 
-  if (useLocal && projectType == VsProjectType::csproj) {
+  if (useLocal && projectType != VsProjectType::vcxproj) {
     // This label is not provided by MSBuild for C# projects.
     script += newline;
     script += this->GetReportErrorLabel();

Source/cmVisualStudio10TargetGenerator.cxx

@@ -248,6 +248,8 @@ static std::string computeProjectFileExtension(VsProjectType projectType)
   switch (projectType) {
     case VsProjectType::csproj:
       return ".csproj";
+    case VsProjectType::proj:
+      return ".proj";
     default:
       return ".vcxproj";
   }
@@ -681,6 +683,8 @@ void cmVisualStudio10TargetGenerator::WriteClassicMsBuildProjectFile(
           .Attribute("Project", VS10_CSharp_DEFAULT_PROPS)
           .Attribute("Condition", "Exists('" VS10_CSharp_DEFAULT_PROPS "')");
         break;
+      default:
+        break;
     }
 
     this->WriteProjectConfigurationValues(e0);
@@ -737,6 +741,8 @@ void cmVisualStudio10TargetGenerator::WriteClassicMsBuildProjectFile(
         case VsProjectType::csproj:
           props = VS10_CSharp_USER_PROPS;
           break;
+        default:
+          break;
       }
       if (cmValue p = this->GeneratorTarget->GetProperty("VS_USER_PROPS")) {
         props = *p;
@@ -779,6 +785,8 @@ void cmVisualStudio10TargetGenerator::WriteClassicMsBuildProjectFile(
           Elem(e0, "Import").Attribute("Project", VS10_CSharp_TARGETS);
         }
         break;
+      default:
+        break;
     }
 
     this->WriteTargetSpecificReferences(e0);
@@ -3057,6 +3065,8 @@ bool cmVisualStudio10TargetGenerator::ComputeClOptions(
         cm::make_unique<Options>(this->LocalGenerator, Options::CSharpCompiler,
                                  gg->GetCSharpFlagTable());
       break;
+    default:
+      break;
   }
   Options& clOptions = *pOptions;
 
@@ -3182,6 +3192,8 @@ bool cmVisualStudio10TargetGenerator::ComputeClOptions(
         return def.find('=') != std::string::npos;
       });
       break;
+    default:
+      break;
   }
   clOptions.AddDefines(targetDefines);
 
@@ -4308,6 +4320,9 @@ void cmVisualStudio10TargetGenerator::AddLibraries(
               this->AdditionalUsingDirectories[config].insert(
                 cmSystemTools::GetFilenamePath(location));
               break;
+            default:
+              // In .proj files, we wouldn't be referencing libraries.
+              break;
           }
         }
       }

Source/cmVsProjectType.h

@@ -7,5 +7,6 @@
 enum class VsProjectType
 {
   vcxproj,
-  csproj
+  csproj,
+  proj,
 };