FIX regression by gitpython-developers#519 on reading stdout/stderr of cmds

Author: ankostis

.appveyor.yml

@@ -38,9 +38,10 @@ environment:
 install:
     - set PATH=%PYTHON%;%PYTHON%\Scripts;%GIT_PATH%;%PATH%
 
-    ## Print architecture, python & git used for debugging.
+    ## Print configuration for debugging.
     #
     - |
+        echo %PATH%
         uname -a
         where git git-daemon python pip pip3 pip34
         python --version

git/cmd.py

@@ -539,7 +539,8 @@ def execute(self, command,
                 cmd_not_found_exception = OSError
         # end handle
 
-        log.debug("Popen(%s, cwd=%s, universal_newlines=%s", command, cwd, universal_newlines)
+        log.debug("Popen(%s, cwd=%s, universal_newlines=%s, shell=%s)",
+                  command, cwd, universal_newlines, shell)
         try:
             proc = Popen(command,
                          env=env,

git/repo/base.py

@@ -899,8 +899,12 @@ def _clone(cls, git, url, path, odb_default_type, progress, **kwargs):
         try:
             proc = git.clone(url, path, with_extended_output=True, as_process=True,
                              v=True, **add_progress(kwargs, git, progress))
-            progress_handler = progress and progress.new_message_handler() or None
-            handle_process_output(proc, None, progress_handler, finalize_process)
+            if progress:
+                handle_process_output(proc, None, progress.new_message_handler(), finalize_process)
+            else:
+                (stdout, stderr) = proc.communicate()
+                finalize_process(proc, stderr=stderr)
+            # end handle progress
         finally:
             if prev_cwd is not None:
                 os.chdir(prev_cwd)