hgweb: make "comparison" get parent from not filelog but changelog
Before this patch, "comparison" shows unexpected result, when the
specified file is not modified in the specified revision, even though
"diff" shows empty result.
When REV doesn't change specified FILE, "diff" shows:
"hg diff -c REV FILE"
but "comparison" shows:
"hg diff -c `hg parents -r REV FILE` FILE"
In other words, the former gets parent from changelog, but the latter
gets one from filelog.
This may confuse users browsing (and switching "diff" and
"comparison" of) files in the specified revision.
This patch makes "comparison" get parent from not filelog but
changelog, to show "hg diff -c REV FILE" in both "diff" and
"comparison" pages.
$ hg init a
$ cd a
$ echo 123 > a
$ hg add a
$ hg commit -m "a" -u a
$ cd ..
$ hg init b
$ cd b
$ echo 321 > b
$ hg add b
$ hg commit -m "b" -u b
$ hg pull ../a
pulling from ../a
searching for changes
abort: repository is unrelated
[255]
$ hg pull -f ../a
pulling from ../a
searching for changes
warning: repository is unrelated
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg heads
changeset: 1:9a79c33a9db3
tag: tip
parent: -1:000000000000
user: a
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
changeset: 0:01f8062b2de5
user: b
date: Thu Jan 01 00:00:00 1970 +0000
summary: b
$ cd ..