This has the advantage of tags being located right by the full command; combined with tags ":tco" to search for the `co` alias will jump right to the `checkout` line, neatly showing everything without needing further navigation. tmux hint from Thomas Adam, thanks. OK stsp

ok jrick

Specifically, obstructed files are versioned files which should be on disk but have been replaced on disk by a non-regular file (e.g. by a directory). The man page used the phrase "deletion was obstructed" which is unrelated to the above concept and can be expressed as "deletion was prevented" instead.

Tyring to write a test to cover this case I found that obstructed files are (correctly) detected as local modifications in the work tree. Thus they trigger the pre-condition check for local modications and 'got merge' will not even start to do any work in the presence of obstructed files.

Additional testing by Thomas Adam. ok tracey

clean output without the use of ignore files. ok stsp

responsive on large repos. ok jrick stsp

Performance problems reported by naddy

While these checks might catch usage mistakes the performance overhead of scanning the entire history of the current branch is not worth it. Measurements provided by naddy, cherrypicking 5 commits of OpenBSD's src repository in usr.bin/rsync: Before: 5m50.33s real 4m02.36s user 2m04.41s system After: 1m04.92s real 0m28.24s user 0m36.54s system Further performance improvements could be needed but this is a first step.

Suggested by Clint Pachl, thanks!

Also, make requirements for branch name arguments more flexible. Absolute reference names are now accepted. ok naddy@

In particular, attempt to describe the -f option better.