git: patch does not apply

Johannes Sixt from the [email protected] mailing list suggested using following command line arguments:

git apply --ignore-space-change --ignore-whitespace mychanges.patch

This solved my problem.

git apply --reject --whitespace=fix mychanges.patch worked for me.

Explanation

The --reject option will instruct git to not fail if it cannot determine how to apply a patch, but instead to apply the individual hunks it can apply and create reject files (.rej) for hunks it cannot apply. Wiggle can "apply [these] rejected patches and perform word-wise diffs".

Additionally, --whitespace=fix will warn about whitespace errors and try to fix them, rather than refusing to apply an otherwise applicable hunk.

Both options together make the application of a patch more robust against failure, but they require additional attention with respect to the result.

For the whole documentation, see https://git-scm.com/docs/git-apply.

When all else fails, try git apply's --3way option.

git apply --3way patchFile.patch

--3way
When the patch does not apply cleanly, fall back on 3-way merge if the patch records the identity of blobs it is supposed to apply to, and we have those blobs available locally, possibly leaving the conflict markers in the files in the working tree for the user to resolve. This option implies the --index option, and is incompatible with the --reject and the --cached options.

Typical fail case applies as much of the patch as it can, and leaves you with conflicts to work out in git however you normally do so. Probably one step easier than the reject alternative.