tests/generate-working-copy-states.py

transaction: support cache file in backupentries

We do not want to abort if anything wrong happen while handling a cache file.
Cache file have way to be invalidated and if old/bad version stay no
misbehavior will happen. Proper value will eventually be computed and the wrong
will be righten.

This changeset use the transaction reporter (usually writing on stderr) to write
details about failed cache handling. This will only apply to write operation
using a transaction. The usual update during read only operation will stay a
debug message.

I was on the way to bring these message back to debug level when I realised it
could be a feature. People with write access to the repository are likely to
have the power to fix error related to cache (and it is valuable to fix them).
So let the things as is for now.

# generate proper file state to test working copy behavior
import sys
import os

# build the combination of possible states
combination = []
for base in [None, 'content1']:
    for parent in set([None, 'content2']) | set([base]):
        for wcc in set([None, 'content3']) | set([base, parent]):
            for tracked in (False, True):
                def statestring(content):
                    return content is None and 'missing' or content
                trackedstring = tracked and 'tracked' or 'untracked'
                filename = "%s_%s_%s-%s" % (statestring(base),
                                            statestring(parent),
                                            statestring(wcc),
                                            trackedstring)
                combination.append((filename, base, parent, wcc))

# make sure we have stable output
combination.sort()

# retrieve the state we must generate
target = sys.argv[1]

# compute file content
content = []
for filename, base, parent, wcc in combination:
    if target == 'filelist':
        print filename
    elif target == 'base':
        content.append((filename, base))
    elif target == 'parent':
        content.append((filename, parent))
    elif target == 'wc':
        # Make sure there is content so the file gets written and can be
        # tracked. It will be deleted outside of this script.
        content.append((filename, wcc or 'TOBEDELETED'))
    else:
        print >> sys.stderr, "unknown target:", target
        sys.exit(1)

# write actual content
for filename, data in content:
    if data is not None:
        f = open(filename, 'w')
        f.write(data + '\n')
        f.close()
    elif os.path.exists(filename):
        os.remove(filename)