`hg merge` is a Mercurial command used for merging revisions into working directory. Use this tag for all questions related to merging with Mercurial.
merge another revision into working directory:
hg merge [-P] [-f] [[-r] REV]
The current working directory is updated with all changes made in the requested revision since the last common predecessor revision.
Options:
-f, --force force a merge including outstanding changes (DEPRECATED)
-r, --rev <REV> revision to merge
-P, --preview review revisions to merge (no merge is performed)
-t, --tool <VALUE> specify merge tool
Reference: https://www.selenic.com/mercurial/hg.1.html#merge