performance: do not stat() things when not required
Ignore unknown files if we don't need them (eg in hg diff).
It slows things down a little bit for big trees (kernel repo), since _join()
is called for each file instead of for each directory.
fix issue567
#!/bin/sh
hg init repo
cd repo
cat > a <<EOF
c
c
a
a
b
a
a
c
c
EOF
hg ci -Am adda
cat > a <<EOF
c
c
a
a
dd
a
a
c
c
EOF
echo '% default context'
hg diff --nodates
echo '% invalid --unified'
hg diff --nodates -U foo
echo '% --unified=2'
hg diff --nodates -U 2
echo '% diff.unified=2'
hg --config diff.unified=2 diff --nodates
echo '% diff.unified=2 --unified=1'
hg diff --nodates -U 1
echo '% invalid diff.unified'
hg --config diff.unified=foo diff --nodates
exit 0