Genex: Make CMP0021 and CMP0022 usable with TARGET_POLICY

Use preprocessor loops and add a unit test for the appropriate
policies. All policies whose value is recorded at target creation
time should be part of this list.

Source/cmGeneratorExpressionEvaluator.cxx

@@ -1033,10 +1033,13 @@ static const struct TargetNameNode : public cmGeneratorExpressionNode
 
 //----------------------------------------------------------------------------
 static const char* targetPolicyWhitelist[] = {
-    "CMP0003"
-  , "CMP0004"
-  , "CMP0008"
-  , "CMP0020"
+  0
+#define TARGET_POLICY_STRING(POLICY) \
+  , #POLICY
+
+  CM_FOR_EACH_TARGET_POLICY(TARGET_POLICY_STRING)
+
+#undef TARGET_POLICY_STRING
 };
 
 cmPolicies::PolicyStatus statusForTarget(cmTarget *tgt, const char *policy)
@@ -1047,10 +1050,7 @@ cmPolicies::PolicyStatus statusForTarget(cmTarget *tgt, const char *policy)
     return tgt->GetPolicyStatus ## POLICY (); \
   } \
 
-  RETURN_POLICY(CMP0003)
-  RETURN_POLICY(CMP0004)
-  RETURN_POLICY(CMP0008)
-  RETURN_POLICY(CMP0020)
+  CM_FOR_EACH_TARGET_POLICY(RETURN_POLICY)
 
 #undef RETURN_POLICY
 
@@ -1066,10 +1066,7 @@ cmPolicies::PolicyID policyForString(const char *policy_id)
     return cmPolicies:: POLICY_ID; \
   } \
 
-  RETURN_POLICY_ID(CMP0003)
-  RETURN_POLICY_ID(CMP0004)
-  RETURN_POLICY_ID(CMP0008)
-  RETURN_POLICY_ID(CMP0020)
+  CM_FOR_EACH_TARGET_POLICY(RETURN_POLICY_ID)
 
 #undef RETURN_POLICY_ID
 
@@ -1099,7 +1096,7 @@ static const struct TargetPolicyNode : public cmGeneratorExpressionNode
 
     context->HadContextSensitiveCondition = true;
 
-    for (size_t i = 0;
+    for (size_t i = 1;
          i < (sizeof(targetPolicyWhitelist) /
               sizeof(*targetPolicyWhitelist));
          ++i)
@@ -1125,8 +1122,17 @@ static const struct TargetPolicyNode : public cmGeneratorExpressionNode
       }
     reportError(context, content->GetOriginalExpression(),
       "$<TARGET_POLICY:prop> may only be used with a limited number of "
-      "policies.  Currently it may be used with policies CMP0003, CMP0004, "
-      "CMP0008 and CMP0020."
+      "policies.  Currently it may be used with the following policies:\n"
+
+#define STRINGIFY_HELPER(X) #X
+#define STRINGIFY(X) STRINGIFY_HELPER(X)
+
+#define TARGET_POLICY_LIST_ITEM(POLICY) \
+      " * " STRINGIFY(POLICY) "\n"
+
+      CM_FOR_EACH_TARGET_POLICY(TARGET_POLICY_LIST_ITEM)
+
+#undef TARGET_POLICY_LIST_ITEM
       );
     return std::string();
   }

Source/cmTarget.cxx

@@ -191,13 +191,14 @@ cmTargetInternals::~cmTargetInternals()
 //----------------------------------------------------------------------------
 cmTarget::cmTarget()
 {
+#define INITIALIZE_TARGET_POLICY_MEMBER(POLICY) \
+  this->PolicyStatus ## POLICY = cmPolicies::WARN;
+
+  CM_FOR_EACH_TARGET_POLICY(INITIALIZE_TARGET_POLICY_MEMBER)
+
+#undef INITIALIZE_TARGET_POLICY_MEMBER
+
   this->Makefile = 0;
-  this->PolicyStatusCMP0003 = cmPolicies::WARN;
-  this->PolicyStatusCMP0004 = cmPolicies::WARN;
-  this->PolicyStatusCMP0008 = cmPolicies::WARN;
-  this->PolicyStatusCMP0020 = cmPolicies::WARN;
-  this->PolicyStatusCMP0021 = cmPolicies::WARN;
-  this->PolicyStatusCMP0022 = cmPolicies::WARN;
   this->LinkLibrariesAnalyzed = false;
   this->HaveInstallRule = false;
   this->DLLPlatform = false;
@@ -1694,18 +1695,13 @@ void cmTarget::SetMakefile(cmMakefile* mf)
   this->SetPropertyDefault("POSITION_INDEPENDENT_CODE", 0);
 
   // Record current policies for later use.
-  this->PolicyStatusCMP0003 =
-    this->Makefile->GetPolicyStatus(cmPolicies::CMP0003);
-  this->PolicyStatusCMP0004 =
-    this->Makefile->GetPolicyStatus(cmPolicies::CMP0004);
-  this->PolicyStatusCMP0008 =
-    this->Makefile->GetPolicyStatus(cmPolicies::CMP0008);
-  this->PolicyStatusCMP0020 =
-    this->Makefile->GetPolicyStatus(cmPolicies::CMP0020);
-  this->PolicyStatusCMP0021 =
-    this->Makefile->GetPolicyStatus(cmPolicies::CMP0021);
-  this->PolicyStatusCMP0022 =
-    this->Makefile->GetPolicyStatus(cmPolicies::CMP0022);
+#define CAPTURE_TARGET_POLICY(POLICY) \
+  this->PolicyStatus ## POLICY = \
+    this->Makefile->GetPolicyStatus(cmPolicies::POLICY);
+
+  CM_FOR_EACH_TARGET_POLICY(CAPTURE_TARGET_POLICY)
+
+#undef CAPTURE_TARGET_POLICY
 }
 
 //----------------------------------------------------------------------------

Source/cmTarget.h

@@ -19,6 +19,14 @@
 
 #include <cmsys/auto_ptr.hxx>
 
+#define CM_FOR_EACH_TARGET_POLICY(F) \
+  F(CMP0003) \
+  F(CMP0004) \
+  F(CMP0008) \
+  F(CMP0020) \
+  F(CMP0021) \
+  F(CMP0022)
+
 class cmake;
 class cmMakefile;
 class cmSourceFile;
@@ -91,29 +99,13 @@ public:
   void SetMakefile(cmMakefile *mf);
   cmMakefile *GetMakefile() const { return this->Makefile;};
 
-  /** Get the status of policy CMP0003 when the target was created.  */
-  cmPolicies::PolicyStatus GetPolicyStatusCMP0003() const
-    { return this->PolicyStatusCMP0003; }
+#define DECLARE_TARGET_POLICY(POLICY) \
+  cmPolicies::PolicyStatus GetPolicyStatus ## POLICY () const \
+    { return this->PolicyStatus ## POLICY; }
 
-  /** Get the status of policy CMP0004 when the target was created.  */
-  cmPolicies::PolicyStatus GetPolicyStatusCMP0004() const
-    { return this->PolicyStatusCMP0004; }
+  CM_FOR_EACH_TARGET_POLICY(DECLARE_TARGET_POLICY)
 
-  /** Get the status of policy CMP0008 when the target was created.  */
-  cmPolicies::PolicyStatus GetPolicyStatusCMP0008() const
-    { return this->PolicyStatusCMP0008; }
-
-  /** Get the status of policy CMP0020 when the target was created.  */
-  cmPolicies::PolicyStatus GetPolicyStatusCMP0020() const
-    { return this->PolicyStatusCMP0020; }
-
-  /** Get the status of policy CMP0021 when the target was created.  */
-  cmPolicies::PolicyStatus GetPolicyStatusCMP0021() const
-    { return this->PolicyStatusCMP0021; }
-
-  /** Get the status of policy CMP0022 when the target was created.  */
-  cmPolicies::PolicyStatus GetPolicyStatusCMP0022() const
-    { return this->PolicyStatusCMP0022; }
+#undef DECLARE_TARGET_POLICY
 
   /**
    * Get the list of the custom commands for this target
@@ -694,12 +686,12 @@ private:
   cmMakefile* Makefile;
 
   // Policy status recorded when target was created.
-  cmPolicies::PolicyStatus PolicyStatusCMP0003;
-  cmPolicies::PolicyStatus PolicyStatusCMP0004;
-  cmPolicies::PolicyStatus PolicyStatusCMP0008;
-  cmPolicies::PolicyStatus PolicyStatusCMP0020;
-  cmPolicies::PolicyStatus PolicyStatusCMP0021;
-  cmPolicies::PolicyStatus PolicyStatusCMP0022;
+#define TARGET_POLICY_MEMBER(POLICY) \
+  cmPolicies::PolicyStatus PolicyStatus ## POLICY;
+
+  CM_FOR_EACH_TARGET_POLICY(TARGET_POLICY_MEMBER)
+
+#undef TARGET_POLICY_MEMBER
 
   // Internal representation details.
   friend class cmTargetInternals;

Tests/RunCMake/CMakeLists.txt

@@ -96,6 +96,7 @@ add_RunCMake_test(list)
 add_RunCMake_test(try_compile)
 add_RunCMake_test(variable_watch)
 add_RunCMake_test(CMP0004)
+add_RunCMake_test(TargetPolicies)
 
 find_package(Qt4 QUIET)
 find_package(Qt5Core QUIET)

Tests/RunCMake/TargetPolicies/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 2.8)
+project(${RunCMake_TEST} NONE)
+include(${RunCMake_TEST}.cmake)

Tests/RunCMake/TargetPolicies/PolicyList-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/TargetPolicies/PolicyList-stderr.txt

@@ -0,0 +1,13 @@
+  Error evaluating generator expression:
+
+    \$<TARGET_POLICY:NOT_A_POLICY>
+
+  \$<TARGET_POLICY:prop> may only be used with a limited number of policies.
+  Currently it may be used with the following policies:
+
+   \* CMP0003
+   \* CMP0004
+   \* CMP0008
+   \* CMP0020
+   \* CMP0021
+   \* CMP0022

Tests/RunCMake/TargetPolicies/PolicyList.cmake

@@ -0,0 +1,8 @@
+
+enable_language(CXX)
+
+add_library(empty empty.cpp)
+target_compile_definitions(empty
+  PRIVATE
+    $<$<TARGET_POLICY:NOT_A_POLICY>:SOME_DEFINE>
+)

Tests/RunCMake/TargetPolicies/RunCMakeTest.cmake

@@ -0,0 +1,3 @@
+include(RunCMake)
+
+run_cmake(PolicyList)

Tests/RunCMake/TargetPolicies/empty.cpp

@@ -0,0 +1,7 @@
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int empty(void)
+{
+  return 0;
+}