merge: introduce a revert_to() for that use-case In the same vein as the previous patch. Differential Revision: https://phab.mercurial-scm.org/D7901

merge: introduce a clean_update() for that use-case I find it hard to understand what value to pass for all the arguments to `merge.update()`. I would like to introduce functions that are more specific to each use-case. We already have `graft()`. This patch introduces a `clean_update()` and uses it in some places to show that it works. Differential Revision: https://phab.mercurial-scm.org/D7902

manifest: fix _very_ subtle bug with exact matchers passed to walk() Prior to this fix, manifestdict.walk() with an exact matcher would blindly list the files in the matcher, even if they weren't in the manifest. This was exposed by my next patch where I rewrite filesnotin() to use walk() instead of matches(). Differential Revision: https://phab.mercurial-scm.org/D8081