cmSourceFile: Move LANGUAGE to GetPropertyForUser

- Remove the special case from cmGetSourceFilePropertyCommand

Tests: check LANGUAGE for source file
- use target_sources to add file
- use get_property to read property value

1 files changed, 7 insertions, 0 deletions

diff --git a/Source/cmSourceFile.cxx b/Source/cmSourceFile.cxx
index 738a1c0..5d738d5 100644
--- a/Source/cmSourceFile.cxx
+++ b/Source/cmSourceFile.cxx
@@ -272,6 +272,13 @@ const char* cmSourceFile::GetPropertyForUser(const std::string& prop)
     this->GetFullPath();
   }
 
+  // Similarly, LANGUAGE can be determined by the file extension
+  // if it is requested by the user.
+  if (prop == propLANGUAGE) {
+    // The c_str pointer is valid until `this->Language` is modified.
+    return this->GetOrDetermineLanguage().c_str();
+  }
+
   // Perform the normal property lookup.
   return this->GetProperty(prop);
 }