obsolete: gather _fm0 meta encoding with other _fm0 code

obsolete: _rename decodemeta to _fm0decodemeta This will be format zero specific.

obsolete: _rename encodemeta to _fm0encodemeta This will be format zero specific.

obsolete: store metadata as a tuple of (key, value) pairs (API) Different formats will encode metadata in different ways. So we cannot keep the binary blob in the object anymore. We use a tuple to ensure it is immutable and hashable.

merge with stable

templater: fix ifcontains when list is a string (issue4399)

shelve: don't delete "." when rebase is a no-op (issue4398) When unshelving and facing a conflict, if we resolve all conflicts in favour of the committed changes instead of the shelved changes, then the ensuing implicit rebase is a no-op. That is, there is nothing to rebase. In this case, there are no extra intermediate shelve commits to strip either. Prior to this change, the commit being unshelved to would be marked for destruction in a rather catastrophic way. The relevant part of the test case failed as follows: $ hg unshelve -c unshelve of 'default' complete $ hg diff warning: ignoring unknown working parent 33f7f61e6c5e! diff --git a/a/a b/a/a new file mode 100644 --- /dev/null b/a/a @@ -0,0 1,3 @@ a c x $ hg status warning: ignoring unknown working parent 33f7f61e6c5e! M a/a ? a/a.orig ? foo/foo $ hg summary warning: ignoring unknown working parent 33f7f61e6c5e! parent: -1:000000000000 (no revision checked out) branch: default commit: 1 modified, 2 unknown (new branch head) update: 4 new changesets (update) With this change, this test case now passes.

merge: make error message consistent with other commands If a merge is attempted when another merge is already ongoing, we give the message "outstanding uncommitted merges". Many other commands (such as backout, rebase, histedit) give the same message in singular form. Since the singular form also seems to make more sense, let's use that for 'hg merge' as well.

test-run-tests: add a test for detection of failure to start a server This also highlights a bug: right now we print "2 failed" but we only ran one test.

run-tests: more accurate/helpful message than "diff generation failed" Diff generation didn't really fail, it recognized that an hg serve server has failed to start, and thus skipped the diff generation intentionally. The most common reason for a server to fail to start is that the port was already in use, so output HGPORT as well, to help finding it (since pgrep -f 'hg serve' is not sufficient, if the command line is something like 'hg -R main serve')