How do you redo the manual merge of just one file in mercurial?

mercurial, merge

Solution

I found it hard to figure this out from the mercurial help and google. I eventually got it by trial and error, though, and thought I'd post what I learned here.

To re-resolve a single file requires a two-step process:

hg resolve -u <file>
hg resolve <file>

Problem

When I perform a merge in mercurial with a number of manual conflict resolutions, sometimes I realize before committing that I've made a mistake in one or two of the files. Short of starting over and redoing the whole merge, how can I tell mercurial to pop up the merge tool for a single file to let me redo the manual conflict resolution?

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