filemerge: when using in-memory merge, always put backup files in temp dir
Before calling a merge tool, we create a backup of the local side of
the merge. That file can be put in the working copy or in a temporary
directory, depending on the user's config. When we're merging in
memory, we don't want to write to the actual, on-disk working copy, so
we write the file to the in-memory working copy instead. However,
since we don't support external merge tools with in-memory merge, it
makes no difference where the file is actually stored (and if we ever
do add support for external merge tools, then the file clearly can't
live in the in-memory working-copy object anyway). So, since it
doesn't matter where the file is stored, we can simplify by always
putting them in the system's temp directory.
Differential Revision: https://phab.mercurial-scm.org/D12187
Create a repo, set the username to something more than 255 bytes, then run hg amend on it.
$ unset HGUSER
$ cat >> $HGRCPATH << EOF
> [ui]
> username = aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa <very.long.name@example.com>
> [extensions]
> amend =
> [experimental]
> evolution.createmarkers=True
> evolution.exchange=True
> EOF
$ hg init tmpa
$ cd tmpa
$ echo a > a
$ hg add
adding a
$ hg commit -m "Initial commit"
$ echo a >> a
$ hg amend 2>&1 | egrep -v '^(\*\*| )'
transaction abort!
rollback completed
Traceback (most recent call last):
*ProgrammingError: obsstore metadata value cannot be longer than 255 bytes (value "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa <very.long.name@example.com>" for key "user" is 285 bytes) (glob)