branch: allow changing branch name to existing name if possible With the functionality added in previous patch we can change branches of a revision but not everytime even if it's possible to do so. For example cosider the following case: o 3 added a (foo) o 2 added b (foo) o 1 added c (bar) o 0 added d (bar) Here if I want to change the branch of rev 2,3 to bar, it was not possible and it will say, "a branch with same name exists". This patch allows us to change branch of 2,3 to bar. The underlying logic for changing branch finds the changesets from the revs passed which have no parents in revs. We only support revsets which have only one such root, so to support this we check whether the parent of the root has the same name as that of the new name and if so, we can use the new name to change branches. Differential Revision: https://phab.mercurial-scm.org/D1913

branch: add a --rev flag to change branch name of given revisions This patch adds a new --rev flag to hg branch which can be used to change branch of revisions. This is motivated from topic extension where you can change topic on revisions but this one has few restrictions which are: 1) You cannot change branch name in between the stack 2) You cannot change branch name and set it to an existing name 3) You cannot change branch of non-linear set of commits 4) You cannot change branch of merge commits. Tests are added for the same. .. feature:: An experimental flag `--rev` to `hg branch` which can be used to change branch of changesets. Differential Revision: https://phab.mercurial-scm.org/D1074

templater: fix crash by empty group expression 'exp' may be None because of '(group None)' node. The error message is copied from revset.py.

log: fix typo in comment about _matchfiles()