External diff tool FileMerge don't start when I press the "Diff Externe" button.

[Patrick Jeanson]

External diff tool FileMerge don't start when I press the "Diff Externe" button. Other external diff tools works correctly such as DiffMerge, but I had to add a softlink.

For FileMerge tool, nothing is modifiable when we select it. Adding a softlink did not improve the situation:

sudo ln -sf /Developer/Applications/Utilities/FileMerge.app/Contents/MacOS/FileMerge /usr/bin/FileMerge

This trick worked file for diffmerge but not for FileMerge.

Here are the details of the links I did:

lrwxr-xr-x 1 root wheel 59 12 fév 10:18 /usr/bin/diffmerge -> /Applications/DiffMerge.app/Contents/Resources/diffmerge.sh
lrwxr-xr-x 1 root wheel 72 13 fév 19:51 /usr/bin/filemerge -> /Developer/Applications/Utilities/FileMerge.app/Contents/MacOS/FileMerge
lrwxr-xr-x 1 root wheel 72 13 fév 19:51 /usr/bin/FileMerge -> /Developer/Applications/Utilities/FileMerge.app/Contents/MacOS/FileMerge

Thanks for your help.

[Patrick Jeanson · Accepted solution]

Thanks for the tip about opendiff as the name.

I ran opendiff on a command line and got:

Mac-mini-de-Patrick:~ patrickjeanson$ opendiff
xcode-select: Error: No Xcode folder is set. Run xcode-select -switch <xcode_folder_path> to set the path to the Xcode folder.
Error: /usr/bin/xcode-select returned unexpected error.

So I did the following command on a terminal:

Mac-mini-de-Patrick:~ patrickjeanson$ sudo xcode-select -switch /Developer
Password:
Mac-mini-de-Patrick:~ patrickjeanson$ opendiff
2012-02-14 18:43:14.542 opendiff[31684:10f] too few arguments
2012-02-14 18:43:14.547 opendiff[31684:10f] usage: opendiff file1 file2 [-ancestor ancestorFile] [-merge mergeFile]

Bingo!

I set the right parameters in SourceTree and the diff was launched properly.

ie. opendiff $BASE $LOCAL

Thanks to all.

Patrick.

[stevestreeting]

Thanks, I'll add this to the Knowledge Base too.

[laguiz]

Quick tips : I just had to run `sudo opendiff` and then accept the license. After opendiff open properly.

SourceTree 1.9.8

XCode 6.0.1

[Becca Owens]

Thank you, this worked great for me.

[Matt]

Worked for me as well. Thank you!

[Christopher Prince]

When I do `sudo opendiff` at the command line, I get:

xcode-select: error: tool 'opendiff' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance

[Justin Vallely]

You need to install Command Line Tools in Xcode Preferences -> Locations (as of Xcode 10.2.1)

[badlydrawnrob]

I've been struggling with this as well — seems it's a problem with other apps, I followed the instructions here http://www.gitboxapp.com/

It doesn't come pre-installed with Command Line tools, install them under Xcode preferences then:

sudo /usr/bin/xcode-select -switch /Applications/Xcode.app/Contents/Developer

That seems to do the trick!

[stevestreeting]

SourceTree actually needs to use the command line tool for FileMerge, which is called 'opendiff'. This should have been installed when you installed XCode, it usually lives in /usr/bin/opendiff.

[stevestreeting]

OK, I think they moved it to /Developer/usr/bin/opendiff. Probably the best way to resolve this is to add /Developer/usr/bin to your /etc/paths - or you could symlink opendiff to somewhere on one of your existing paths.

[stevestreeting]

Hmm, actually I wonder whether this is installed if you've only ever installed XCode from the Mac App Store. If it's missing, that would explain things, but I wonder where it's gone in that case.

[Jonathan Ferguson]

I also needed to run

sudo opendiff

as Xcode was complaining that I'd not agreed to the license. After this File Merge worked as expected.

Thank you.