[PATCH V2] histedit: add a config allowing changing histedit rule line length limit

[Mateusz Kwapich]

# HG changeset patch
# User Mateusz Kwapich <mitrandir at fb.com>
# Date 1421880324 28800
#      Wed Jan 21 14:45:24 2015 -0800
# Node ID e75e5456ec6971fb50263ca4526291d9a10ff01a
# Parent  ff5caa8dfd993680d9602ca6ebb14da9de10d5f4
histedit: add a config allowing changing histedit rule line length limit

Since many users are using terminals wider than 80 chars there should be an
option to have longer lines in histedit editor.

Even if the summary line is shorter than 80 chars after adding action line
prefixes (like "pick 7c2fd3b9020c") it doesn't fit there anymore. Setting
it to for example 110 would be a  nice option to have.

diff --git a/hgext/histedit.py b/hgext/histedit.py
--- a/hgext/histedit.py
+++ b/hgext/histedit.py
@@ -142,6 +142,10 @@ If you run ``hg histedit --outgoing`` on
 as running ``hg histedit 836302820282``. If you need plan to push to a
 repository that Mercurial does not detect to be related to the source
 repo, you can add a ``--force`` option.
+
+Histedit rule lines are truncated to 80 characters by default. You can
+customize this behaviour by setting histedit.linelen in your hg config
+to desired length.
 """
 
 try:
@@ -638,7 +642,7 @@ def _histedit(ui, repo, state, *freeargs
 
         ctxs = [repo[r] for r in revs]
         if not rules:
-            rules = '\n'.join([makedesc(c) for c in ctxs])
+            rules = '\n'.join([makedesc(ui, c) for c in ctxs])
             rules += '\n\n'
             rules += editcomment % (node.short(root), node.short(topmost))
             rules = ui.edit(rules, ui.username())
@@ -805,7 +809,7 @@ def between(repo, old, new, keep):
             raise util.Abort(_('cannot edit immutable changeset: %s') % root)
     return [c.node() for c in ctxs]
 
-def makedesc(c):
+def makedesc(ui, c):
     """build a initial action line for a ctx `c`
 
     line are in the form:
@@ -817,7 +821,9 @@ def makedesc(c):
         summary = c.description().splitlines()[0]
     line = 'pick %s %d %s' % (c, c.rev(), summary)
     # trim to 80 columns so it's not stupidly wide in my editor
-    return util.ellipsis(line, 80)
+    maxlen = ui.configint('histedit', 'linelen', default=80)
+    maxlen = max(maxlen, 22) # avoid truncating hash
+    return util.ellipsis(line, maxlen)
 
 def verifyrules(rules, repo, ctxs):
     """Verify that there exists exactly one edit rule per given changeset.