diff: re-establish linear runtime performance
The previous method with sum() and list() creates a new list object
for every hunk. Then sum() is used to flatten out this sequence of
lists. The sum() function is not "lazy", but creates a new list object
for every "+" operation and so this code had quadratic runtime behaviour.
'''
Examples of useful python hooks for Mercurial.
'''
from __future__ import absolute_import
from mercurial import (
patch,
util,
)
def diffstat(ui, repo, **kwargs):
'''Example usage:
[hooks]
commit.diffstat = python:/path/to/this/file.py:diffstat
changegroup.diffstat = python:/path/to/this/file.py:diffstat
'''
if kwargs.get('parent2'):
return
node = kwargs['node']
first = repo[node].p1().node()
if 'url' in kwargs:
last = repo.changelog.tip()
else:
last = node
diff = patch.diff(repo, first, last)
ui.write(patch.diffstat(util.iterlines(diff)))