ENH: Re-enable diagnosis of non-unique target names.

- Re-enable enforcement in cmMakefile::EnforceUniqueName
  - Improve error message to help user resolve the problem
  - Fix Modules/CTestTargets.cmake to not duplicate testing targets
  - Move commands used by the changes to Modules/CTestTargets.cmake
    to build during bootstrap: DEFINE_PROPERTY, GET_PROPERTY

Modules/CTestTargets.cmake

@@ -35,32 +35,35 @@ IF(CMAKE_CONFIGURATION_TYPES)
   SET(__conf_types -C "${CMAKE_CFG_INTDIR}")
 ENDIF(CMAKE_CONFIGURATION_TYPES)
 
-# add testing targets
-IF(${CMAKE_MAKE_PROGRAM} MATCHES make)
-  FOREACH(mode Experimental Nightly Continuous NightlyMemoryCheck)
-    ADD_CUSTOM_TARGET(${mode} ${CMAKE_CTEST_COMMAND} ${__conf_types} -D ${mode})
-  ENDFOREACH(mode)
-ELSE(${CMAKE_MAKE_PROGRAM} MATCHES make)
-  # for IDE only add them once for nested projects
-  IF (NOT DART_COMMON_TARGETS_ADDED)
-    FOREACH(mode Experimental Nightly Continuous NightlyMemoryCheck)
-      ADD_CUSTOM_TARGET(${mode} ${CMAKE_CTEST_COMMAND} ${__conf_types} -D ${mode})
-    ENDFOREACH(mode)
-    SET (DART_COMMON_TARGETS_ADDED 1)
-  ENDIF (NOT DART_COMMON_TARGETS_ADDED)
-ENDIF(${CMAKE_MAKE_PROGRAM} MATCHES make)
+# Add convenience targets.  Do this at most once in case of nested
+# projects.
+DEFINE_PROPERTY(CTEST_TARGETS_ADDED GLOBAL
+  "Internal property used by CTestTargets module."
+  "Set by the CTestTargets module to track addition of testing targets."
+  FALSE)
+GET_PROPERTY(_CTEST_TARGETS_ADDED GLOBAL PROPERTY CTEST_TARGETS_ADDED)
+IF(NOT _CTEST_TARGETS_ADDED)
+  SET_PROPERTY(GLOBAL PROPERTY CTEST_TARGETS_ADDED 1)
 
+  # For all generators add basic testing targets.
+  FOREACH(mode Experimental Nightly Continuous NightlyMemoryCheck)
+    ADD_CUSTOM_TARGET(${mode}
+      ${CMAKE_CTEST_COMMAND} ${__conf_types} -D ${mode}
+      )
+  ENDFOREACH(mode)
 
-# for non IDE based builds nmake and make 
-# add all these extra targets 
-IF(${CMAKE_MAKE_PROGRAM} MATCHES make)
+  # For Makefile generators add more granular targets.
+  IF("${CMAKE_GENERATOR}" MATCHES Make)
     # Make targets for Experimental builds
     FOREACH(mode Nightly Experimental Continuous)
-    FOREACH(testtype Start Update Configure Build Test Coverage MemCheck Submit)
+      FOREACH(testtype
+          Start Update Configure Build Test Coverage MemCheck Submit
           # missing purify
+          )
         ADD_CUSTOM_TARGET(${mode}${testtype}
-        ${CMAKE_CTEST_COMMAND} ${__conf_types} -D ${mode}${testtype})
+          ${CMAKE_CTEST_COMMAND} ${__conf_types} -D ${mode}${testtype}
+          )
       ENDFOREACH(testtype)
     ENDFOREACH(mode)
-ENDIF (${CMAKE_MAKE_PROGRAM} MATCHES make)
-
+  ENDIF("${CMAKE_GENERATOR}" MATCHES Make)
+ENDIF(NOT _CTEST_TARGETS_ADDED)

Source/cmBootstrapCommands.cxx

@@ -34,6 +34,7 @@
 #include "cmConfigureFileCommand.cxx"
 #include "cmCoreTryCompile.cxx"
 #include "cmCreateTestSourceList.cxx"
+#include "cmDefinePropertyCommand.cxx"
 #include "cmElseCommand.cxx"
 #include "cmEnableTestingCommand.cxx"
 #include "cmEndForEachCommand.cxx"
@@ -56,6 +57,7 @@
 #include "cmGetCMakePropertyCommand.cxx"
 #include "cmGetDirectoryPropertyCommand.cxx"
 #include "cmGetFilenameComponentCommand.cxx"
+#include "cmGetPropertyCommand.cxx"
 #include "cmGetSourceFilePropertyCommand.cxx"
 #include "cmGetTargetPropertyCommand.cxx"
 #include "cmHexFileConverter.cxx"
@@ -103,6 +105,7 @@ void GetBootstrapCommands(std::list<cmCommand*>& commands)
   commands.push_back(new cmCMakeMinimumRequired);
   commands.push_back(new cmConfigureFileCommand);
   commands.push_back(new cmCreateTestSourceList);
+  commands.push_back(new cmDefinePropertyCommand);
   commands.push_back(new cmElseCommand);
   commands.push_back(new cmEnableTestingCommand);  
   commands.push_back(new cmEndForEachCommand);
@@ -122,6 +125,7 @@ void GetBootstrapCommands(std::list<cmCommand*>& commands)
   commands.push_back(new cmGetCMakePropertyCommand);
   commands.push_back(new cmGetDirectoryPropertyCommand);
   commands.push_back(new cmGetFilenameComponentCommand);
+  commands.push_back(new cmGetPropertyCommand);
   commands.push_back(new cmGetSourceFilePropertyCommand);
   commands.push_back(new cmGetTargetPropertyCommand);
   commands.push_back(new cmIfCommand);

Source/cmCommands.cxx

@@ -18,14 +18,12 @@
 #if defined(CMAKE_BUILD_WITH_CMAKE)
 #include "cmAuxSourceDirectoryCommand.cxx"
 #include "cmBuildNameCommand.cxx"
-#include "cmDefinePropertyCommand.cxx"
 #include "cmElseIfCommand.cxx"
 #include "cmEnableLanguageCommand.cxx"
 #include "cmEndWhileCommand.cxx"
 #include "cmExportCommand.cxx"
 #include "cmExportLibraryDependencies.cxx"
 #include "cmFLTKWrapUICommand.cxx"
-#include "cmGetPropertyCommand.cxx"
 #include "cmGetTestPropertyCommand.cxx"
 #include "cmIncludeExternalMSProjectCommand.cxx"
 #include "cmInstallCommand.cxx"
@@ -64,14 +62,12 @@ void GetPredefinedCommands(std::list<cmCommand*>&
 #if defined(CMAKE_BUILD_WITH_CMAKE)
   commands.push_back(new cmAuxSourceDirectoryCommand);
   commands.push_back(new cmBuildNameCommand);
-  commands.push_back(new cmDefinePropertyCommand);
   commands.push_back(new cmElseIfCommand);
   commands.push_back(new cmEnableLanguageCommand);
   commands.push_back(new cmEndWhileCommand);
   commands.push_back(new cmExportCommand);
   commands.push_back(new cmExportLibraryDependenciesCommand);
   commands.push_back(new cmFLTKWrapUICommand);
-  commands.push_back(new cmGetPropertyCommand);
   commands.push_back(new cmGetTestPropertyCommand);
   commands.push_back(new cmIncludeExternalMSProjectCommand);
   commands.push_back(new cmInstallCommand);

Source/cmMakefile.cxx

@@ -3156,7 +3156,6 @@ bool cmMakefile::EnforceUniqueName(std::string const& name, std::string& msg)
       msg = e.str();
       return false;
       }
-#if 0 /* disable until CTestTargets can be fixed */
     else if(!this->NeedBackwardsCompatibility(2, 4))
       {
       // The conflict is with a non-imported target.  Produce an error
@@ -3165,9 +3164,10 @@ bool cmMakefile::EnforceUniqueName(std::string const& name, std::string& msg)
       e << "cannot create target \"" << name
         << "\" because another target with the same name already exists.  "
         << "Logical target names must be globally unique.  "
-        << "Consider using the OUTPUT_NAME target property to create "
-        << "two targets with the same physical name while keeping logical "
-        << "names distinct.\n"
+        << "For executables and libraries, consider using the OUTPUT_NAME "
+        << "target property to create two targets with the same physical "
+        << "name while keeping logical names distinct.  "
+        << "Custom targets must simply have globally unique names.\n"
         << "If you are building an older project it is possible that "
         << "it violated this rule but was working accidentally.  "
         << "Set CMAKE_BACKWARDS_COMPATIBILITY to 2.4 or lower to disable "
@@ -3175,7 +3175,6 @@ bool cmMakefile::EnforceUniqueName(std::string const& name, std::string& msg)
       msg = e.str();
       return false;
       }
-#endif
     }
   return true;
 }