refactor(cmd): streamline usage of creationflags

Author: Byron

git/cmd.py

@@ -43,9 +43,6 @@
     safe_decode,
 )
 
-# value of Windows process creation flag taken from MSDN
-CREATE_NO_WINDOW = 0x08000000
-
 execute_kwargs = ('istream', 'with_keep_cwd', 'with_extended_output',
                   'with_exceptions', 'as_process', 'stdout_as_string',
                   'output_stream', 'with_stdout', 'kill_after_timeout',
@@ -249,6 +246,9 @@ class Git(LazyMixin):
     # Enables debugging of GitPython's git commands
     GIT_PYTHON_TRACE = os.environ.get("GIT_PYTHON_TRACE", False)
 
+    # value of Windows process creation flag taken from MSDN
+    CREATE_NO_WINDOW = 0x08000000
+    
     # Provide the full path to the git executable. Otherwise it assumes git is in the path
     _git_exec_env_var = "GIT_PYTHON_GIT_EXECUTABLE"
     GIT_PYTHON_GIT_EXECUTABLE = os.environ.get(_git_exec_env_var, git_exec_name)
@@ -611,12 +611,8 @@ def execute(self, command,
                 cmd_not_found_exception = OSError
         # end handle
 
+        creationflags = self.CREATE_NO_WINDOW if sys.platform == 'win32' else 0
         try:
-            if sys.platform == 'win32':
-                creationflags = CREATE_NO_WINDOW
-            else:
-                creationflags = 0
-
             proc = Popen(command,
                          env=env,
                          cwd=cwd,
@@ -638,11 +634,6 @@ def execute(self, command,
 
         def _kill_process(pid):
             """ Callback method to kill a process. """
-            if sys.platform == 'win32':
-                creationflags = CREATE_NO_WINDOW
-            else:
-                creationflags = 0
-
             p = Popen(['ps', '--ppid', str(pid)], stdout=PIPE, creationflags=creationflags)
             child_pids = []
             for line in p.stdout: