[backport to 3.6] Support "bpo-" in Misc/NEWS (#42)

(cherry picked from commit 79ab8be)

Doc/tools/extensions/pyspecific.py

@@ -34,7 +34,7 @@
 
 
 ISSUE_URI = 'https://bugs.python.org/issue%s'
-SOURCE_URI = 'https://hg.python.org/cpython/file/3.6/%s'
+SOURCE_URI = 'https://github.com/python/cpython/tree/3.6/%s'
 
 # monkey-patch reST parser to disable alphabetic and roman enumerated lists
 from docutils.parsers.rst.states import Body
@@ -79,7 +79,7 @@ def new_depart_literal_block(self, node):
 
 def issue_role(typ, rawtext, text, lineno, inliner, options={}, content=[]):
     issue = utils.unescape(text)
-    text = 'issue ' + issue
+    text = 'bpo-' + issue
     refnode = nodes.reference(text, text, refuri=ISSUE_URI % issue)
     return [refnode], []
 
@@ -225,7 +225,7 @@ def run(self):
 
 # Support for including Misc/NEWS
 
-issue_re = re.compile('([Ii])ssue #([0-9]+)')
+issue_re = re.compile('(?:[Ii]ssue #|bpo-)([0-9]+)')
 whatsnew_re = re.compile(r"(?im)^what's new in (.*?)\??$")
 
 
@@ -253,7 +253,7 @@ def run(self):
             text = 'The NEWS file is not available.'
             node = nodes.strong(text, text)
             return [node]
-        content = issue_re.sub(r'`\1ssue #\2 <https://bugs.python.org/\2>`__',
+        content = issue_re.sub(r'`bpo-\1 <https://bugs.python.org/issue\1>`__',
                                content)
         content = whatsnew_re.sub(r'\1', content)
         # remove first 3 lines as they are the main heading