add a script to print releases timeline in RST format; also show a di…

…ff between versions in the timeline section of the doc

scripts/internal/print_timeline.py

@@ -0,0 +1,53 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2009 Giampaolo Rodola'. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""
+Prints releases' timeline in RST format.
+"""
+
+import subprocess
+
+
+entry = """\
+- {date}:
+  `{ver} <https://pypi.python.org/pypi?name=psutil&version={ver}&:action=files>`__ -
+  `what's new <https://github.com/giampaolo/psutil/blob/master/HISTORY.rst#{nodotver}>`__ -
+  `diff <https://github.com/giampaolo/psutil/compare/{prevtag}...{tag}#files_bucket>`__"""  # NOQA
+
+
+def sh(cmd):
+    return subprocess.check_output(
+        cmd, shell=True, universal_newlines=True).strip()
+
+
+def get_tag_date(tag):
+    out = sh(r"git log -1 --format=%ai {}".format(tag))
+    return out.split(' ')[0]
+
+
+def main():
+    releases = []
+    out = sh("git tags")
+    for line in out.split('\n'):
+        tag = line.split(' ')[0]
+        ver = tag.replace('release-', '')
+        nodotver = ver.replace('.', '')
+        date = get_tag_date(tag)
+        releases.append((tag, ver, nodotver, date))
+    releases.sort(reverse=True)
+
+    for i, rel in enumerate(releases):
+        tag, ver, nodotver, date = rel
+        try:
+            prevtag = releases[i + 1][0]
+        except IndexError:
+            # get first commit
+            prevtag = sh("git rev-list --max-parents=0 HEAD")
+        print(entry.format(**locals()))
+
+
+if __name__ == '__main__':
+    main()