Mercurial merge strategy per file type

Question

All:

I want to use kdiff to merge all files with a certain suffix (say *.c, *.h) and I want to do two things (turn off premerge and use internal:other) for all files

Answer 1

According to this Mercurial MergeToolConfiguration page, you should put the interal:other directly after the match pattern:

[merge-patterns]
**.mdl = internal:other

Answer 2

Merge tools can use any executable file. To set up a merge tool which always overwrites $base with $other, you can use the following:

[merge-tools]
clobbermerge.priority = 100
clobbermerge.premerge = False
clobbermerge.args = $other $output
clobbermerge.executable = <copy executable>

When using this strategy on Windows, there is one problem. You cannot simply replace <copy executable> with the copy shell command. For some reason, Mercurial fails to find shell commands in this context. I have not tried this on *nix.

To work around this problem, you can create a distribute a batch file that performs the copy. It simply needs to run: copy %1 %2. Once placed on your PATH, you can set clobbermerge.executable=clobber.bat.

If you have kdiff3 installed (comes with TortoiseHg on Windows), you can get the same results without the external batch file using a configuration like this:

[merge-tools]
clobbermerge.priority = 100
clobbermerge.premerge = False
clobbermerge.args = --auto $base $other $other -o $output
clobbermerge.executable = kdiff3

The key to this configuration is the args field:

• --auto: tells kdiff3 not to open the GUI if there are no conflicts
• $base $other $other: tells kdiff3 to only use $other
• $output: tells kdiff3 the name of the output file