templater: consistently join() string-like object per character (BC) The old behavior was copied from join() of a lazy generator string, which was unified to the behavior of join() of a byte string by the previous patch. This patch fixes the mappable type to do the same.

templater: always join() over a wrapped object (BC) This is a behavior change in a sense that join() of a byte string is no longer "implementation dependent." Before, if a byte string was backed by a lazy generator, join() would concatenate each chunk with the specified separator, which seems wrong. The new behavior is always join() each byte. TypeError on join() over uniterable is also fixed.

templater: add wrapped types for pure non-list/dict values These wrapper types will allow us to get rid of some isinstance() business. A bytes object needs to support sequence-like operations (e.g. join(), ifcontains(), etc.) That's why we have two wrapper classes. Tests will be added later.

templater: unify unwrapvalue() with _unwrapvalue() All weird generators got removed from the hgweb codebase. We still have inconsistent behavior regarding join() of a byte string, which will be addressed later.

templater: inline unwrapvalue() The current unwrapvalue() will be superseded by _unwrapvalue(). Note that _unwrapvalue() can simply return thing.tovalue() if thing is a wrapped object. That's because tovalue() is guaranteed to not return a generator of strings.

run-tests: update the test case name format Manually typing parenthesis and spaces will be tedious when trying to launch a specific test case. I'm proposing a simpler format that is less hard to remember and type right. There was other possibilities envisaged like `::` or `!`, I think `#` is slight easier to type but I'm open to any suggestion on the new format. Differential Revision: https://phab.mercurial-scm.org/D3556

run-tests: add support for running specific test cases Differential Revision: https://phab.mercurial-scm.org/D3555

configitems: drop the deprecated alias for commands.update.check experimental.updatecheck was deprecated and should have been removed once 4.4 was released. Let's drop it now. Differential Revision: https://phab.mercurial-scm.org/D3679

graft: correct documentation about options can be reapplied Now options --user and --date can be reapplied after we hit a conflict. Differential Revision: https://phab.mercurial-scm.org/D3678

cmdutil: use internal separators when building the terse list Status uses internal separators, so this is more correct. See c974320d20b9 and 362096cfdb1f. A utility method is still needed, so that the paths starting with '/' aren't created when `self.path` is empty.