tests/test-dispatch.py.out

patch: make parsepatch optionally trim context lines

Previously there is a suspicious `if False and delta > 0` which dates back
to the beginning of hgext/record.py (b2607267236d).

The "trimming context lines" feature could be useful (and is used by the
next patch). So let's enable it. This patch adds a new `maxcontext`
parameter to `recordhunk` and `parsepatch`, changing the `if False`
condition to respect it.

The old `trimcontext` implementation is also wrong - it does not update
`toline` correctly and it does not do the right thing for `before` context.
A doctest was added to guard us from making a similar mistake again.

Since `maxcontext` is set to `None` (unlimited), there is no behavior
change.

running: init test1
result: None
running: add foo
result: 0
running: commit -m commit1 -d 2000-01-01 foo
result: None
running: commit -m commit2 -d 2000-01-02 foo
result: None
running: log -r 0
changeset:   0:0e4634943879
user:        test
date:        Sat Jan 01 00:00:00 2000 +0000
summary:     commit1

result: None
running: log -r tip
changeset:   1:45589e459b2e
tag:         tip
user:        test
date:        Sun Jan 02 00:00:00 2000 +0000
summary:     commit2

result: None