dirs: use mutable integers internally These integers are not visible to Python code, so this is safe. perfdirs results for a working dir with 170,000 files: Python 638 msec C 244 C+int 192

scmutil: rewrite dirs in C, use if available This is over twice as fast as the Python dirs code. Upcoming changes will nearly double its speed again. perfdirs results for a working dir with 170,000 files: Python 638 msec C 244

scmutil: use new dirs class in dirstate and context The multiset-of-directories code was open coded in each of these modules; this change gets rid of the duplication.

scmutil: add a dirs class This encapsulates the "multiset of directories" structures that are currently open-coded (and duplicated) in both the dirstate and context modules. This will be used, and optionally replaced by a C implementation, in upcoming changes.

scmutil: migrate finddirs from dirstate

merge

manifestmerge: handle workdir removed, remote removed with flags This can happen when a file with flags is removed or deleted in the working directory and also not present in m2. The obvious solution is to add a __delitem__ override to manifestdict that removes the file from flags if necessary, but that has a significant performance cost in some cases, e.g. hg status --rev rev1 --rev rev2 <file>.

dicthelpers.diff: compare against default for missing values This is not only a bit faster, but also aligns with callers' expectations better since we can legitimately have manifestdict's _flags set to '' instead of unset. hg perfmergecalculate -r . before: ! wall 0.139582 comb 0.140000 user 0.140000 sys 0.000000 (best of 59) after: ! wall 0.126154 comb 0.120000 user 0.120000 sys 0.000000 (best of 74) hg perfmergecalculate -r .^ before: ! wall 0.236333 comb 0.240000 user 0.240000 sys 0.000000 (best of 36) after: ! wall 0.212265 comb 0.210000 user 0.210000 sys 0.000000 (best of 45)

templater: back out 0615b22da148, it breaks schemes ({1})

debuglabelcomplete: compute active branch heads correctly The previous computation was simply wrong.