ENH: Move CMP0004 check into cmTarget

This moves code implementing policy CMP0004 into cmTarget::CheckCMP0004.
The implementation is slightly simpler and can be re-used outside of
cmComputeLinkDepends.

1 files changed, 59 insertions, 0 deletions

diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index 3d6e1b7..6cddbe3 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -3815,6 +3815,65 @@ cmTarget::ComputeLinkInterface(const char* config)
 }
 
 //----------------------------------------------------------------------------
+std::string cmTarget::CheckCMP0004(std::string const& item)
+{
+  // Strip whitespace off the library names because we used to do this
+  // in case variables were expanded at generate time.  We no longer
+  // do the expansion but users link to libraries like " ${VAR} ".
+  std::string lib = item;
+  std::string::size_type pos = lib.find_first_not_of(" \t\r\n");
+  if(pos != lib.npos)
+    {
+    lib = lib.substr(pos, lib.npos);
+    }
+  pos = lib.find_last_not_of(" \t\r\n");
+  if(pos != lib.npos)
+    {
+    lib = lib.substr(0, pos+1);
+    }
+  if(lib != item)
+    {
+    cmake* cm = this->Makefile->GetCMakeInstance();
+    switch(this->PolicyStatusCMP0004)
+      {
+      case cmPolicies::WARN:
+        {
+        cmOStringStream w;
+        w << (this->Makefile->GetPolicies()
+              ->GetPolicyWarning(cmPolicies::CMP0004)) << "\n"
+          << "Target \"" << this->GetName() << "\" links to item \""
+          << item << "\" which has leading or trailing whitespace.";
+        cm->IssueMessage(cmake::AUTHOR_WARNING, w.str(),
+                         this->GetBacktrace());
+        }
+      case cmPolicies::OLD:
+        break;
+      case cmPolicies::NEW:
+        {
+        cmOStringStream e;
+        e << "Target \"" << this->GetName() << "\" links to item \""
+          << item << "\" which has leading or trailing whitespace.  "
+          << "This is now an error according to policy CMP0004.";
+        cm->IssueMessage(cmake::FATAL_ERROR, e.str(), this->GetBacktrace());
+        }
+        break;
+      case cmPolicies::REQUIRED_IF_USED:
+      case cmPolicies::REQUIRED_ALWAYS:
+        {
+        cmOStringStream e;
+        e << (this->Makefile->GetPolicies()
+              ->GetRequiredPolicyError(cmPolicies::CMP0004)) << "\n"
+          << "Target \"" << this->GetName() << "\" links to item \""
+          << item << "\" which has leading or trailing whitespace.";
+        cm->IssueMessage(cmake::FATAL_ERROR, e.str(), this->GetBacktrace());
+        }
+        break;
+      }
+    }
+  return lib;
+}
+
+//----------------------------------------------------------------------------
 cmComputeLinkInformation*
 cmTarget::GetLinkInformation(const char* config)
 {