How to use p4merge as the merge/diff tool for Mercurial?

Question

Does anyone know how to setup Mercurial to use p4merge as the merge/diff tool on OS X 10.5?

Answer 1

This will work for merging:

Place this into your ~/.hgrc (or, optionally, your Mercurial.ini on Windows):

[merge-tools] p4.priority = 100 p4.premerge = True  # change this to False if you're don't trust hg's internal merge p4.executable = /Applications/p4merge.app/Contents/MacOS/p4merge p4.gui = True p4.args = $base $local $other $output 

Requires Mercurial 1.0 or newer. Clearly you'll need to update the path to that executable to reflect where you'd got p4merge installed.

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You can't change what hg diff uses; but you can use the extdiff extension to create new diff commands that use the display you want.

So hg pdiff could run p4 merge, etc.

Answer 2

I found Ry4an's answer to be a good solution, except for a minor problem, which left p4merge (under mac os) mixing up the command inputs. Do everything described in his answer and add the following line in the [merge-tools] section:

p4.args=$base $local $other $output 

This line tells mercurial in which order p4merge takes its arguments.