dirstate walking optimizations
The repo walking code introduces a number of calls to dirstate.map.copy(),
significantly slowing down the walk on large trees. When a list of
files is passed to the walking code, we should only look at map entries
relevant to the file list passed in.
dirstate.filterfiles() is added to return a subset of the dirstate map.
The subset includes in files passed in, and if one of the files requested
is actually a directory, it includes any files inside that directory tree.
This brings the time for hg diff Makefile down from 1.7s to .3s on
a linux kernel repo.
Also, the diff command was unconditionally calling makewalk, leading
to an extra pass through repo.changes. This patch avoids the call
to makewalk when commands.diff isn't given a list of patterns, cutting
the time for hg diff (with no args) in half.
Index: mine/mercurial/hg.py
===================================================================
#!/bin/sh
mkdir t
cd t
hg init
echo "added file1" > file1
echo "added file2" > file2
hg add file1 file2
hg commit -m "added file1 and file2" -d "0 0" -u user
echo "changed file1" >> file1
hg commit -m "changed file1" -d "0 0" -u user
hg -q log
hg id
hg update -C 0
hg id
echo "changed file1" >> file1
hg id
hg revert
hg diff
hg status
hg id
hg update
hg diff
hg status
hg id
hg update -C 0
echo "changed file1 different" >> file1
HGMERGE=merge hg update
hg diff | sed -e "s/\(\(---\|+++\) [a-zA-Z0-9_/.-]*\).*/\1/" -e "s/\(<<<<<<<\|>>>>>>>\) .*/\1/"
hg status
hg id
hg revert
hg diff
hg status
hg id
hg revert -r tip
hg diff
hg status
hg id
hg update -C
hg diff
hg status
hg id
cd ..; /bin/rm -rf t