dirstate: add --minimal flag to debugrebuilddirstate On repositories with hundreds of thousands of files, hg debugrebuilddirstate causes every dirstate entry to be marked lookup, and the next hg status can take many minutes. This adds a --minimal flag that allows us to only rebuild the parts of the dirstate that are inconsistent. This follows two rules: 1) If a file is in the dirstate but not in the parent manifest, and it is not marked 'add', it is busted and we should drop it. 2) If a file is not in the dirstate at all, but it is in the parent manifest, it should be added to the dirstate and we need to mark it as lookup. This allows us to fix repositories where the dirstate doesn't match the manifest much more quickly. Tested by artificially adding bad dirstate entries (via code) for both cases above.

tests: make filterpyflakes.py read target files relatively to cwd Before this patch, 'filterpyflakes.py' reads target files relatively to own location. But this prevents third party tools from using it in own source tree, because their files are placed separately from 'filterpyflakes.py'. In fact, 'test-check-pyflakes.t', which is the only user of 'filterpyflakes.py', changes current working directory (cwd) to the root of "test target" source tree before using it. Therefore, composing the root of source tree in 'filterpyflakes.py' is redundant. This patch makes 'filterpyflakes.py' read target files relatively to cwd by invoking 'open()' without any path composition. This also removes importing 'os' module, because there is no user of it after this patch. This is a one of preparation of issue4677.