1. When a module is run from an EditorWindow, if its directory is not in

sys.path, prepend it.  This allows the module to import other modules
   in the same directory.  Do the same for a script run from the command
   line.
2. Tweak the IDLE usage message a bit more.

SF Bug 706860 (closed)
SF Patch 686254 (reject specific solution)
SF Patch 507327 (similar)

M PyShell.py
M ScriptBinding.py

Lib/idlelib/PyShell.py

@@ -526,6 +526,18 @@ def stuffsource(self, source):
         linecache.cache[filename] = len(source)+1, 0, lines, filename
         return filename
 
+    def prepend_syspath(self, filename):
+        "Prepend sys.path with file's directory if not already included"
+        self.runcommand("""if 1:
+            _filename = %s
+            import sys as _sys
+            from os.path import dirname as _dirname
+            _dir = _dirname(_filename)
+            if not _dir in _sys.path:
+                _sys.path.insert(0, _dir)
+            del _filename, _sys, _dirname, _dir
+            \n""" % `filename`)
+
     def showsyntaxerror(self, filename=None):
         """Extend base class method: Add Colorizing
 
@@ -1069,9 +1081,9 @@ def isatty(self):
 
 usage_msg = """\
 
-USAGE: idle  [-deis] [-t title] [file]*
-       idle  [-ds] [-t title] (-c cmd | -r file) [arg]*
-       idle  [-ds] [-t title] - [arg]*
+USAGE: idle  [-deins] [-t title] [file]*
+       idle  [-dns] [-t title] (-c cmd | -r file) [arg]*
+       idle  [-dns] [-t title] - [arg]*
 
   -h         print this help message and exit
   -n         run IDLE without a subprocess (see Help/IDLE Help for details)
@@ -1234,6 +1246,7 @@ def main():
         if cmd:
             shell.interp.execsource(cmd)
         elif script:
+            shell.interp.prepend_syspath(script)
             shell.interp.execfile(script)
     root.mainloop()
     root.destroy()

Lib/idlelib/ScriptBinding.py

@@ -144,8 +144,9 @@ def run_module_event2(self, interp, filename, code):
             if (not _sys.argv or
                 _basename(_sys.argv[0]) != _basename(_filename)):
                 _sys.argv = [_filename]
-                del _filename, _sys, _basename
-                \n""" % `filename`)
+            del _filename, _sys, _basename
+            \n""" % `filename`)
+        interp.prepend_syspath(filename)
         interp.runcode(code)
 
     def getfilename(self):