Fix cold cache diff performance cold cache diff performance has regressed in two ways. localrepo.changes has optimizations for diffing against the working dir parent that expect node1 to be None. commands.revpair() usage means that commands.dodiff() never sends node1 == None. This is fixed in localrepo.changes by checking against the dirstate parents. In the non-dirstate parents case, localrepo.changes does a loop comparing files without first sorting the file names, leading to random access across the disk.

#!/bin/sh

# No local source
hg clone a b
echo $?

# No remote source
hg clone http://127.0.0.1:3121/a b
echo $?
rm -rf b # work around bug with http clone

# Inaccessible source
mkdir a
chmod 000 a
hg clone a b
echo $?

# Inaccessible destination
mkdir b
cd b
hg init
hg clone . ../a
echo $?
cd ..
chmod 700 a
rm -rf a b

# Source of wrong type
mkfifo a
hg clone a b
echo $?
rm a

# Default destination, same directory
mkdir q
cd q
hg init
cd ..
hg clone q

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