commands: tidy up merge state decoding in resolve Make the mapping from merge state to label and display key explicit, and move construction of the dict out of the loop. Differential Revision: https://phab.mercurial-scm.org/D861

tests: add test for path conflicts during merge Differential Revision: https://phab.mercurial-scm.org/D787

tests: add test for path conflicts during update Differential Revision: https://phab.mercurial-scm.org/D786

context: also consider path conflicts when clearing unknown files When clearing unknown files to remove path conflicts, also delete files that conflict with the target file's path. Differential Revision: https://phab.mercurial-scm.org/D785

merge: check for path conflicts when merging (issue5628) When merging, check for any path conflicts introduced by the manifest merge and rename the conflicting file to a safe name. Differential Revision: https://phab.mercurial-scm.org/D784

util: add safename function for generating safe names to rename to This function finds a name which does not clash with any other name in the manifest, and so can be used to safely rename a file. Differential Revision: https://phab.mercurial-scm.org/D783