purge: abort with missing files avoiding problems with name-mangling fs
In a name mangling filesystem (e.g. a case insensitive one)
dirstate.walk() can yield filenames different from the ones
stored in the dirstate. This already confuses the status and
add commands, but with purge this may cause data loss.
To prevent this purge refuses to work if there are missing
files and has a 'force' option if the user knows it is safe.
Even with the force option purge checks if any of the missing
files is still available in the working dir: if so there
may be some problem with the underlying filesystem, so it
unconditionally aborts.
#!/bin/sh
echo % init foo-base
hg init foo-base
echo % create alpha in first repo
cd foo-base
echo 'alpha' > alpha
hg ci -A -m 'add alpha' -d '1 0'
cd ..
echo % clone foo-base to foo-work
hg clone foo-base foo-work
echo % create beta in second repo
cd foo-work
echo 'beta' > beta
hg ci -A -m 'add beta' -d '2 0'
cd ..
echo % create gamma in first repo
cd foo-base
echo 'gamma' > gamma
hg ci -A -m 'add gamma' -d '3 0'
cd ..
echo % pull into work and merge
cd foo-work
hg pull -q
hg merge
echo % revert to changeset 1 to simulate a failed merge
rm alpha beta gamma
hg up -C 1