Created originally on Bitbucket by marmoute (Pierre-Yves David)
Right now, during merge, issues with the formatter result in an abort. Format-source is an helper extension, it should not get in the way.
We should keep merging in case of trouble, only issuing warning so that user can figure out what's wrong in case of actual trouble.
For explicite formatting (hg format-source call) error should still result in aborting.