Mac app: Make our PYTHONPATH manager work for it

Fixes #1321

spyderlib/widgets/externalshell/baseshell.py

@@ -28,14 +28,14 @@
 from spyderlib.py3compat import is_text_string, to_text_string
 
 
-def add_pathlist_to_PYTHONPATH(env, pathlist):
+def add_pathlist_to_PYTHONPATH(env, pathlist, drop_env=False):
     # PyQt API 1/2 compatibility-related tests:
     assert isinstance(env, list)
     assert all([is_text_string(path) for path in env])
 
     pypath = "PYTHONPATH"
     pathstr = os.pathsep.join(pathlist)
-    if os.environ.get(pypath) is not None:
+    if os.environ.get(pypath) is not None and not drop_env:
         for index, var in enumerate(env[:]):
             if var.startswith(pypath+'='):
                 env[index] = var.replace(pypath+'=',

spyderlib/widgets/externalshell/pythonshell.py

@@ -476,10 +476,9 @@ def create_process(self):
 
         # IPython kernel
         env.append('IPYTHON_KERNEL=%r' % self.is_ipykernel)
-
-        pathlist = []
 
-        # Fix encoding with custom "sitecustomize.py"
+        # Add sitecustomize path to path list 
+        pathlist = []
         scpath = osp.dirname(osp.abspath(__file__))
         pathlist.append(scpath)
 
@@ -510,8 +509,8 @@ def create_process(self):
         # 1. PYTHONPATH and PYTHONHOME are set while bootstrapping the app,
         #    but their values are messing sys.path for external interpreters
         #    (e.g. EPD) so we need to remove them from the environment.
-        # 2. Add this file's dir to PYTHONPATH. This will make every external
-        #    interpreter to use our sitecustomize script.
+        # 2. Set PYTHONPATH again but without grabbing entries defined in the
+        #    environment (Fixes Issue 1321)
         # 3. Remove PYTHONOPTIMIZE from env so that we can have assert
         #    statements working with our interpreters (See Issue 1281)
         if running_in_mac_app():
@@ -520,8 +519,7 @@ def create_process(self):
                 env = [p for p in env if not (p.startswith('PYTHONPATH') or \
                                               p.startswith('PYTHONHOME'))] # 1.
 
-                env.append('PYTHONPATH=%s' % osp.dirname(__file__))        # 2.
-
+                add_pathlist_to_PYTHONPATH(env, pathlist, drop_env=True)   # 2.
             env = [p for p in env if not p.startswith('PYTHONOPTIMIZE')]   # 3.
 
         self.process.setEnvironment(env)

spyderlib/widgets/externalshell/sitecustomize.py

@@ -180,11 +180,6 @@ def write(self, text):
     if MAC_APP_NAME in __file__:
         interpreter = os.environ.get('SPYDER_INTERPRETER')
         if MAC_APP_NAME not in interpreter:
-            # We added this file's dir to PYTHONPATH (in pythonshell.py)
-            # so that external interpreters can import this script, and
-            # now we are removing it
-            del os.environ['PYTHONPATH']
-
             # Add a minimal library (with spyderlib) at the end of sys.path to
             # be able to connect our monitor to the external console
             py_ver = '%s.%s' % (sys.version_info[0], sys.version_info[1])