I don't understand why there is a pause before the first wdiff is run.

    $ darcs diff --diff-command 'wdiff -3 %1 %2' .bash_profile
    Running command 'wdiff -3 old-Preferences/.bash_profile new-Preferences/.bash_profile'
    Hit return to move on...

More generally, I'd like to be able to tell darcs not to pause after
each --diff-command or --external-merge invocation.

It would also be useful to tell darcs whether the --diff-command or
--external-merge is recursive, or needs to be called on individual
files.

The 'Hit return to move on' is to cope with (graphical) tools that exit
immediately rather than when the graphical tool itself exits.  As Trent says, it
might be nice to be able to disable this behaviour, perhaps with an environment
variable?

I actually need this to write the test for #189 -- that is, I need a way to make
the whole operation fail without user intervention when the command invoked by
--external-merge fails. Otherwise, the test just hangs.

On Mon, Mar 02, 2009 at 01:02:45 -0000, Samuel Bronson wrote:
> I actually need this to write the test for #189 -- that is, I need a way to make
> the whole operation fail without user intervention when the command invoked by
> --external-merge fails. Otherwise, the test just hangs.

We have a trick for 'hitting Enter' in test scripts (see
tests/toolbox.sh).  Would it be relevant here?

On Mon, Mar 2, 2009 at 3:13 AM, Eric Kow <bugs@darcs.net> wrote:
>
> Eric Kow <kowey@darcs.net> added the comment:
>
> On Mon, Mar 02, 2009 at 01:02:45 -0000, Samuel Bronson wrote:
>> I actually need this to write the test for #189 -- that is, I need a way to make
>> the whole operation fail without user intervention when the command invoked by
>> --external-merge fails. Otherwise, the test just hangs.
>
> We have a trick for 'hitting Enter' in test scripts (see
> tests/toolbox.sh).  Would it be relevant here?

No, that won't really help. The output from this portion of the test
(I obviously haven't written a dummy merge tool yet ;-) is:

# try to merge them with --external-merge
cd lhc
darcs pull -a ../jhc --external-merge='xxdiff -m -O -M %o %1 %a %2'
Pulling from "/home/naesten/hacking/haskell/darcs/work/bugs/jhc"...
Backing up ./src/Foo(-darcs-backup0)
We have conflicts in the following files:
./src/Foo
Merging file ./src/Foo by hand.
Running command 'xxdiff -m -O -M /tmp/merged/./src/Foo
/tmp/version1/./src/Foo /tmp/ancestor/./src/Foo
/tmp/version2/./src/Foo'
External merge command exited with ExitFailure 2
Hit return to move on, ^C to abort the whole operation...

And I certainly don't want it to move on in that situation, since
that's exactly the sort of situation I want the test to fail in.
(Though my dummy merge tool should report which inputs were missing,
unlike xxdiff.)

Marking ProbablyEasy

Just need a UI suggestion for this.  Either a flag pair --pause-for-gui
--no-pause-for-gui (for example) or an environment variable should do.  Do-er
decides likely (though I'll probably poll darcs-users to make sure there aren't
any vehement objections... carefully avoiding the ensuing bikeshed :-D)

The following patch sent by Michael Hendricks <michael@ndrix.org> updated issue issue1228 with
status=has-patch

* Resolve issue1228: Add --pause-for-gui to diff, pull and apply 
Ignore-this: 7db469b6753ee4b4be0bdefb6702d6d7

When using an external diff tool via '--diff-command' or an
external merge tool via '--external-merge', the current behavior
assumes the tool is a GUI which requires darcs to pause (asking
the user to press Enter) before deleting any temporary files.

This patch leaves the default behavior as described above, but
provides an option --no-pause-for-gui which skips the "Press
Enter" prompt.  This option is particularly helpful for external
diff tools (such as colordiff or wdiff) which produce output
before exiting.

Because the desired pause behavior is a function of the
diff/merge tool, this is implemented as a command line option
(like --diff-command and --external-merge) instead of an
environment variable. This lets one specify the pause behavior in
the same way as one specifies the tool.

The following patch sent by Michael Hendricks <michael@ndrix.org> updated issue issue1228 with
status=resolved;resolvedin=2.8.0 HEAD

* Resolve issue1228: Add --pause-for-gui to diff, pull and apply 
Ignore-this: 7db469b6753ee4b4be0bdefb6702d6d7

When using an external diff tool via '--diff-command' or an
external merge tool via '--external-merge', the current behavior
assumes the tool is a GUI which requires darcs to pause (asking
the user to press Enter) before deleting any temporary files.

This patch leaves the default behavior as described above, but
provides an option --no-pause-for-gui which skips the "Press
Enter" prompt.  This option is particularly helpful for external
diff tools (such as colordiff or wdiff) which produce output
before exiting.

Because the desired pause behavior is a function of the
diff/merge tool, this is implemented as a command line option
(like --diff-command and --external-merge) instead of an
environment variable. This lets one specify the pause behavior in
the same way as one specifies the tool.