resolve: do not crash on empty mergestate
I managed to get an empty .hg/merge/state file by interrupting a merge
by pressing Control-C. This lead to this error:
TypeError: a2b_hex() argument 1 must be string or read-only buffer,
not None
since localnode is assigned None before the iteration over lines in
the mergestate begins.
%%% should show a removed and b added
A b
R a
reverting...
undeleting a
forgetting b
%%% should show b unknown and a back to normal
? b
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
created new head
merging a
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
%%% should show foo-b
foo-b
%%% should show a removed and b added
A b
R a
%%% revert should fail
abort: uncommitted merge - please provide a specific revision
%%% revert should be ok now
undeleting a
forgetting b
%%% should show b unknown and a marked modified (merged)
M a
? b
%%% should show foo-b
foo-b