cmLocalGenerator: collapse the path after construction

The path may contain `..` or `.` components naïvely, so compute them out
before letting the generator handle them.

Source/cmLocalGenerator.cxx

@@ -2011,6 +2011,8 @@ bool cmLocalGenerator::GetRealDependency(const std::string& inName,
     dep = cmStrCat(this->GetCurrentBinaryDirectory(), '/', inName);
   }
 
+  dep = cmSystemTools::CollapseFullPath(dep, this->GetBinaryDirectory());
+
   return true;
 }
 

Tests/CustomCommand/CMakeLists.txt

@@ -535,6 +535,7 @@ set_property(SOURCE "${gen_file}" PROPERTY SYMBOLIC ON)
 add_custom_target(command_expand_lists ALL DEPENDS "${gen_file}")
 set_property(TARGET command_expand_lists PROPERTY CMPARGS "${cmp_args}")
 
+# This also tests that `./` is squeezed out of the resulting path.
 set(depends_path "./depended_upon_path.txt")
 
 add_custom_command(