util._matcher: speed up regexp matching.
In 4babaa52badf, Benoit made a change that substantially slows matching
when a big .hgignore file is in play, because it calls into the regexp
matching engine potentially hundreds of times per file to be matched.
I've partly rolled back his change, so that we only call into the matcher
once per file, but preserved the ability to report a meaningful error
message if there's a syntax error in the regexp.
#!/bin/sh
cat <<EOF > merge
import sys, os
print "merging for", os.path.basename(sys.argv[1])
EOF
HGMERGE="python ../merge"; export HGMERGE
mkdir t
cd t
hg init
echo This is file a1 > a
hg add a
hg commit -m "commit #0" -d "1000000 0"
echo This is file b1 > b
hg add b
hg commit -m "commit #1" -d "1000000 0"
hg update 0
echo This is file c1 > c
hg add c
hg commit -m "commit #2" -d "1000000 0"
echo This is file b1 > b
echo %% no merges expected
hg merge 1
hg diff --nodates
hg status
cd ..; rm -r t
mkdir t
cd t
hg init
echo This is file a1 > a
hg add a
hg commit -m "commit #0" -d "1000000 0"
echo This is file b1 > b
hg add b
hg commit -m "commit #1" -d "1000000 0"
hg update 0
echo This is file c1 > c
hg add c
hg commit -m "commit #2" -d "1000000 0"
echo This is file b2 > b
echo %% merge should fail
hg merge 1
echo %% merge of b expected
hg merge -f 1
hg diff --nodates
hg status
cd ..; rm -r t
echo %%
mkdir t
cd t
hg init
echo This is file a1 > a
hg add a
hg commit -m "commit #0" -d "1000000 0"
echo This is file b1 > b
hg add b
hg commit -m "commit #1" -d "1000000 0"
echo This is file b22 > b
hg commit -m "commit #2" -d "1000000 0"
hg update 1
echo This is file c1 > c
hg add c
hg commit -m "commit #3" -d "1000000 0"
echo 'Contents of b should be "this is file b1"'
cat b
echo This is file b22 > b
echo %% merge fails
hg merge 2
echo %% merge expected!
hg merge -f 2
hg diff --nodates
hg status
cd ..; rm -r t
mkdir t
cd t
hg init
echo This is file a1 > a
hg add a
hg commit -m "commit #0" -d "1000000 0"
echo This is file b1 > b
hg add b
hg commit -m "commit #1" -d "1000000 0"
echo This is file b22 > b
hg commit -m "commit #2" -d "1000000 0"
hg update 1
echo This is file c1 > c
hg add c
hg commit -m "commit #3" -d "1000000 0"
echo This is file b33 > b
echo %% merge of b should fail
hg merge 2
echo %% merge of b expected
hg merge -f 2
hg diff --nodates
hg status