move run_doctests utility to top-level tools directory

nltk/tbl/_run_doctests.py

-#!/usr/bin/python3
-# -*- coding: utf-8 -*-
-"""
-run the doctests in nltk.tag.tbl
-"""
-
-
-from __future__ import print_function
-import glob, sys, subprocess, os.path
-from os.path import abspath
-
-currdir = os.getcwd()
-if not currdir.endswith("nltk/tbl"):
-    raise RuntimeError("run me in /<PATH/TO/NLTK>/nltk/tbl/")
-sys.path.insert(0, "../../..")
-
-#a list of all the python files in this dir and two levels of subdirs
-files = [pyfile for patt in ("*.py", "*/*.py", "*/*/*.py") for pyfile in glob.glob(patt)
-         if not abspath(__file__) == abspath(pyfile)]
-
-for pyver in ["python2.6", "python2.7", "python3.2", "python3.3"]:
-    for (i, f) in enumerate(files, 1):
-        print(pyver, i, f, file=sys.stderr)
-        subprocess.call([pyver,  "-m", "doctest", f])
-
-

tools/run_doctests.py

+#!/usr/bin/python3
+# -*- coding: utf-8 -*-
+"""
+run doctests
+"""
+
+from __future__ import print_function
+import sys, subprocess, os
+
+for root, dirs, filenames in os.walk('.'):
+    for filename in filenames:
+        if filename.endswith('.py'):
+            path = os.path.join(root, filename)
+            for pyver in ["python2.6", "python2.7", "python3.2"]:
+                print(pyver, filename, file=sys.stderr)
+                subprocess.call([pyver,  "-m", "doctest", path])