cmTarget: Evaluate CMP0026 and CMP0051 in calling context

These policies should be checked at the call site that tries to access
the LOCATION or SOURCES property, not the directory scope containing the
target.  Thread the caller context through cmTarget::GetProperty to use
for checking the policy setting and emitting a diagnostic with proper
backtrace.

Extend the RunCMake.CMP0026 and RunCMake.CMP0051 tests with
cross-directory cases.

Source/cmGetPropertyCommand.cxx

@@ -302,7 +302,8 @@ bool cmGetPropertyCommand::HandleTargetMode()
     }
   if(cmTarget* target = this->Makefile->FindTargetToUse(this->Name))
     {
-    return this->StoreResult(target->GetProperty(this->PropertyName));
+    return this->StoreResult(target->GetProperty(this->PropertyName,
+                                                 this->Makefile));
     }
   else
     {

Source/cmGetTargetPropertyCommand.cxx

@@ -38,7 +38,7 @@ bool cmGetTargetPropertyCommand
   else if(cmTarget* tgt = this->Makefile->FindTargetToUse(targetName))
     {
     cmTarget& target = *tgt;
-    const char* prop_cstr = target.GetProperty(args[2]);
+    const char* prop_cstr = target.GetProperty(args[2], this->Makefile);
     if(prop_cstr)
       {
       prop = prop_cstr;

Source/cmTarget.cxx

@@ -3178,7 +3178,7 @@ const char* cmTarget::GetFeature(const std::string& feature,
 }
 
 //----------------------------------------------------------------------------
-bool cmTarget::HandleLocationPropertyPolicy() const
+bool cmTarget::HandleLocationPropertyPolicy(cmMakefile* context) const
 {
   if (this->IsImported())
     {
@@ -3187,7 +3187,7 @@ bool cmTarget::HandleLocationPropertyPolicy() const
   cmOStringStream e;
   const char *modal = 0;
   cmake::MessageType messageType = cmake::AUTHOR_WARNING;
-  switch (this->Makefile->GetPolicyStatus(cmPolicies::CMP0026))
+  switch (context->GetPolicyStatus(cmPolicies::CMP0026))
     {
     case cmPolicies::WARN:
       e << (this->Makefile->GetPolicies()
@@ -3208,7 +3208,7 @@ bool cmTarget::HandleLocationPropertyPolicy() const
       << this->GetName() << "\".  Use the target name directly with "
       "add_custom_command, or use the generator expression $<TARGET_FILE>, "
       "as appropriate.\n";
-    this->Makefile->IssueMessage(messageType, e.str());
+    context->IssueMessage(messageType, e.str());
     }
 
   return messageType != cmake::FATAL_ERROR;
@@ -3216,6 +3216,13 @@ bool cmTarget::HandleLocationPropertyPolicy() const
 
 //----------------------------------------------------------------------------
 const char *cmTarget::GetProperty(const std::string& prop) const
+{
+  return this->GetProperty(prop, this->Makefile);
+}
+
+//----------------------------------------------------------------------------
+const char *cmTarget::GetProperty(const std::string& prop,
+                                  cmMakefile* context) const
 {
   if (this->GetType() == INTERFACE_LIBRARY
       && !whiteListedInterfaceProperty(prop))
@@ -3223,7 +3230,7 @@ const char *cmTarget::GetProperty(const std::string& prop) const
     cmOStringStream e;
     e << "INTERFACE_LIBRARY targets may only have whitelisted properties.  "
          "The property \"" << prop << "\" is not allowed.";
-    this->Makefile->IssueMessage(cmake::FATAL_ERROR, e.str());
+    context->IssueMessage(cmake::FATAL_ERROR, e.str());
     return 0;
     }
 
@@ -3242,7 +3249,7 @@ const char *cmTarget::GetProperty(const std::string& prop) const
     {
     if(prop == "LOCATION")
       {
-      if (!this->HandleLocationPropertyPolicy())
+      if (!this->HandleLocationPropertyPolicy(context))
         {
         return 0;
         }
@@ -3263,7 +3270,7 @@ const char *cmTarget::GetProperty(const std::string& prop) const
     // Support "LOCATION_<CONFIG>".
     if(cmHasLiteralPrefix(prop, "LOCATION_"))
       {
-      if (!this->HandleLocationPropertyPolicy())
+      if (!this->HandleLocationPropertyPolicy(context))
         {
         return 0;
         }
@@ -3278,7 +3285,7 @@ const char *cmTarget::GetProperty(const std::string& prop) const
       std::string configName(prop.c_str(), prop.size() - 9);
       if(configName != "IMPORTED")
         {
-        if (!this->HandleLocationPropertyPolicy())
+        if (!this->HandleLocationPropertyPolicy(context))
           {
           return 0;
           }
@@ -3416,7 +3423,7 @@ const char *cmTarget::GetProperty(const std::string& prop) const
           bool noMessage = true;
           cmOStringStream e;
           cmake::MessageType messageType = cmake::AUTHOR_WARNING;
-          switch(this->Makefile->GetPolicyStatus(cmPolicies::CMP0051))
+          switch(context->GetPolicyStatus(cmPolicies::CMP0051))
             {
             case cmPolicies::WARN:
               e << (this->Makefile->GetPolicies()
@@ -3437,7 +3444,7 @@ const char *cmTarget::GetProperty(const std::string& prop) const
             "read at configure time.  Code reading that property needs to be "
             "adapted to ignore the generator expression using the "
             "string(GENEX_STRIP) command.";
-            this->Makefile->IssueMessage(messageType, e.str());
+            context->IssueMessage(messageType, e.str());
             }
           if (addContent)
             {

Source/cmTarget.h

@@ -231,6 +231,7 @@ public:
   void AppendProperty(const std::string&  prop, const char* value,
           bool asString=false);
   const char *GetProperty(const std::string& prop) const;
+  const char *GetProperty(const std::string& prop, cmMakefile* context) const;
   bool GetPropertyAsBool(const std::string& prop) const;
   void CheckProperty(const std::string& prop, cmMakefile* context) const;
 
@@ -587,7 +588,7 @@ public:
                             const std::string &compatibilityType) const;
 
 private:
-  bool HandleLocationPropertyPolicy() const;
+  bool HandleLocationPropertyPolicy(cmMakefile* context) const;
 
   // The set of include directories that are marked as system include
   // directories.