extdiff: prevent exception on double-translation
The docstring is translated twice: once when used as a format string,
and once on display. The second translation fails when the first
translation introduces non-ASCII characters in the string.
The problem is that the gettext module calls unicode(message) on the
string, i.e., it decodes it to a Unicode string using the ASCII
encoding (the default encoding). By translating it into a Unicode
string here, the unicode() call becomes a noop.
#!/bin/sh
hg init a
cd a
touch empty1
hg add empty1
hg commit -m 'add empty1' -d '1000000 0'
touch empty2
hg add empty2
hg commit -m 'add empty2' -d '1000000 0'
hg up -C 0
touch empty3
hg add empty3
hg commit -m 'add empty3' -d '1000000 0'
hg heads
hg merge 1
# before changeset 05257fd28591, we didn't notice the
# empty file that came from rev 1.
hg status
hg commit -m merge -d '1000000 0'
hg manifest --debug tip