Now that we store and display merge labels in user prompts (not just
conflict markets), we should rely on labels to clarify the two sides of a
merge operation (hg merge, hg update, hg rebase etc).
"remote" is not a great name here, as it conflates "remote" as in "remote
server" with "remote" as in "the side of the merge that's further away". In
cases where you're merging the "wrong way" around, remote can even be the
"local" commit that you're merging with something pulled from the remote
server.
Now that we persist the labels, we can consistently use the labels in
prompts for the user without risk of confusion. This changes a huge amount
of command output:
This means that merge prompts like:
no tool found to merge a
keep (l)ocal, take (o)ther, or leave (u)nresolved? u
and
remote changed a which local deleted
use (c)hanged version, leave (d)eleted, or leave (u)nresolved? c
become:
no tool found to merge a
keep (l)ocal [working copy], take (o)ther [destination], or leave (u)nresolved? u
and
remote [source] changed a which local [dest] deleted
use (c)hanged version, leave (d)eleted, or leave (u)nresolved? c
where "working copy" and "destination" were supplied by the command that
requested the merge as labels for conflict markers, and thus should be
human-friendly.
This function will host loading of template aliases. It is not defined at
templater, but at formatter, since formatter is the module handling ui stuff
in front of templater.
New frommapfile() function will make it clear when template aliases will be
loaded. They should be applied to command arguments and templates in hgrc,
but not to map files. Otherwise, our stock styles and web templates
(i.e map-file templates) could be modified unintentionally.
Future patches will add "aliases" argument to __init__(), but not to
frommapfile().
It makes far more sense to leave these conflicts unresolved and kick back to
the user than to just assume that the local version be chosen. There are almost
certainly buggy scripts and applications using Mercurial in the wild that do
merges or rebases non-interactively, and then assume that if the operation
succeeded there's nothing the user needs to pay attention to.
(This wasn't possible earlier because there was no way to re-resolve
change/delete conflicts -- but now it is.)
It makes far more sense to leave these conflicts unresolved and kick back to
the user than to just assume that the local version be chosen. There are almost
certainly buggy scripts and applications using Mercurial in the wild that do
merges or rebases non-interactively, and then assume that if the operation
succeeded there's nothing the user needs to pay attention to.
The ':fail' tool now knows to write out the changed side for change/delete
conflicts.
This has no impact right now but will make things better when we move
change/delete conflicts in here.
We do this because we don't want to modify the dirstate for failures, and don't
just want to leave the file missing from disk. Plus it's more useful for the
user if the changed side is written out -- it is easier to delete a file than
to get it back via hg revert.
For --tool or HGMERGE, we could have either:
(a) proceeded with the particular tool, then failed the merge.
(b) chosen to prompt regardless.
We're explicitly choosing (b) here, because it's effectively what we've been
doing so far and helps maintain an easier-to-use interface.
However, in future patches we're going to change the default selection from
'pick changed version' to 'leave unresolved'. That fixes most of the brokenness
involved with choice (b).
We're going to support the filemerge code resolving change/delete conflicts in
upcoming patches. Some of these resolutions require that the dirstate be
modified. Modifying the dirstate directly from in here would be (a) a pretty
bad layering violation and (b) wrong because all dirstate removals should
happen before adds. So in this and upcoming patches we're instead going to pass
whether the file is deleted up to merge.mergestate, then in there figure out
what dirstate action needs to be taken.
Most code is going to barf at the return values here (particularly from data
and size), so we restrict it to the filemerge code.
This is already somewhat supported via:
ctx.filectx(f, fileid=nullid)
Indeed, for add/add conflicts (ancestor doesn't have the file) we use precisely
that. However, that is broken in subtle ways:
- The cmp() function in filectx returns False (identical) for such a filectx
when compared to a zero-length file.
- size() returns 0 rather than some sort of value indicating that the file isn't
present.
- data() returns '' rather than some sort of value indicating that the file isn't
present.
Given the relatively niche use of such filectxes, this seems to be the simplest
way to fix all these issues.
Having .orig files litter your working copy is a common complaint. This patch
uses cmdutil.orig to let the user determine where those files should reside.
Previously we'd abort the merge entirely if there was an EOF at the prompt.
This is unnecessary -- it's much better to simply fail and treat the file as
unresolved instead.
Very often in my life I'm finding that the only configured merge tool
present on the system is vimdiff[0], and it's currently impossible (as
far as I can tell) short of specifying `ui.merge = `[1] to actually
*disable* a merge tool. This allows vimdiff-haters to put:
[merge-tools]
vimdiff.disable = yes
in their ~/.hgrc and never see vimdiff again. I'm stopping short of
putting this as a commented out entry in the sample new user hgrc
(seen when a user runs `hg config --edit` with no ~/.hgrc) for now,
but I might come back and do that later.
0: vimdiff is at an awkward intersection: it's usually installed by
the vim package which is often installed as a vi substitute, so it's
mere presence doesn't imply me wanting it, unlike (say) kdiff3.
1: There's a related problem I ran into today where specifying
`ui.merge = :merge` failed because :merge isn't a command, which I
think is a regression. I'll try and figure that out and at least file
a bug.
The current output for a failed merge with conflict markers looks something like:
merging foo
warning: conflicts during merge.
merging foo incomplete! (edit conflicts, then use 'hg resolve --mark')
merging bar
warning: conflicts during merge.
merging bar incomplete! (edit conflicts, then use 'hg resolve --mark')
We're going to change the way merges are done to perform all premerges before
all merges, so that the output above would look like:
merging foo
merging bar
warning: conflicts during merge.
merging foo incomplete! (edit conflicts, then use 'hg resolve --mark')
warning: conflicts during merge.
merging bar incomplete! (edit conflicts, then use 'hg resolve --mark')
The 'warning: conflicts during merge' line has no context, so is pretty
confusing.
This patch will change the future output to:
merging foo
merging bar
warning: conflicts while merging foo! (edit, then use 'hg resolve --mark')
warning: conflicts while merging bar! (edit, then use 'hg resolve --mark')
The hint on how to resolve the conflicts makes this a bit unwieldy, but solving
that is tricky because we already hint that people run 'hg resolve' to retry
unresolved merges. The 'hg resolve --mark' mostly applies to conflict marker
based resolution.
This means that in ms.resolve we must call merge after calling premerge. This
doesn't yet mean that all premerges happen before any merges -- however, this
does get us closer to our goal.
The output differences are because we recompute the merge tool. The only
user-visible difference caused by this patch is that if the tool is missing
we'll print the warning twice. Not a huge deal, though.
We're soon going to call this function twice, once for premerge and once for
merge. This makes sure the "merging" output only gets printed during the
premerge step.
The merge code currently does (in pseudocode):
for f in tomerge:
premerge f
merge f
We'd like to change this to look more like:
for f in tomerge:
premerge f
for f in tomerge:
merge f
This makes sure as many files are resolved as possible before prompting for the
others. This restructuring is also necessary for custom merge drivers.
This function separates out the premerge step from the merge step. In future
patches we'll actually turn these into separate steps in the merge driver.
The 'if r:' occurrences will be cleaned up in subsequent patches.
