[PATCH v4 4/4] BaseTools: Fix string concatenation

["PierreGondois" <pierre.gondois@arm.com>]

From: Pierre Gondois <pierre.gondois@arm.com>

Using Python 3.7.2 on win32, when printing a FileBuildRule
instance, the following error occurs:
File "edk2\BaseTools\Source\Python\AutoGen\BuildEngine.py",
line 177, in __str__
  DestString = ", ".join(self.DestFileList)
  TypeError: sequence item 0: expected str instance, PathClass found

This patch converts each PathClass element of the list to a string
instance before concatenating them.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
---

The changes can be seen at https://github.com/PierreARM/edk2/commits/803_Compile_AML_bytecode_array_into_OBJ_file_v4

Notes:
    Notes:
      v2:
       - No v1 for this patch. Fix a __str__ method. [Pierre]
      v3:
       - No modification. [Pierre]
      v4:
       - No modification. Re-sending the patch with base64
         encoding to conserve the right line endings. [Bob]

 BaseTools/Source/Python/AutoGen/BuildEngine.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/BaseTools/Source/Python/AutoGen/BuildEngine.py b/BaseTools/Source/Python/AutoGen/BuildEngine.py
index d602414ca41f37155c9c6d00eec54ea3918840c3..722fead75af6d60aa82365d999837cd5ac3299af 100644
--- a/BaseTools/Source/Python/AutoGen/BuildEngine.py
+++ b/BaseTools/Source/Python/AutoGen/BuildEngine.py
@@ -172,7 +172,7 @@ class FileBuildRule:
     def __str__(self):
         SourceString = ""
         SourceString += " %s %s %s" % (self.SourceFileType, " ".join(self.SourceFileExtList), self.ExtraSourceFileList)
-        DestString = ", ".join(self.DestFileList)
+        DestString = ", ".join([str(i) for i in self.DestFileList])
         CommandString = "\n\t".join(self.CommandList)
         return "%s : %s\n\t%s" % (DestString, SourceString, CommandString)
 
-- 
'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'