Use hg summary to check the status of my files.
Looking for (clean) to make sure the changes are committed and there is nothing to merge.
Example of clean status
> hg summary parent: 12:267d20bf2b03 tip merged rev.tex branch: default commit: 20 unknown (clean) update: (current)
Example when the changed is not committed and there is a merge in the repository.
parent: 8:43cedbe623e7 merged rev.tex branch: default commit: 1 modified, 20 unknown update: 2 new changesets, 2 branch heads (merge)