templater: use template context to render old-style list template Prepares for dropping the 'templ' resource. This means old-style list templates are processed by the same engine class as the one for the list node. I think that's fine since templates for the same list should be tightly coupled, and I believe the extension point for the engine classes isn't actually used. Now templatekw._showlist() is a compatibility wrapper for _showcompatlist(), and will be deprecated soon. The function is still marked as private since I plan to change the interface to get rid of closures capturing context and mapping.

templater: add context.preload(t) to test if the specified template exists I'm going to remove 'templ' from the resources dict because it is the only resource that the caller can't provide. This also implies that putting 'templ' into the resources dict creates a reference cycle. context.preload(t) will be used in place of templater.__contains__().

annotate: pack line content into annotateline object (API) Just for code readability. We can do that since the annotateline type is no longer used while computing the history.

annotate: drop linenumber flag from fctx.annotate() (API) Now linenumber=True is fast enough to be enabled by default.

annotate: do not construct attr.s object per line while computing history Unfortunately, good abstraction has a cost. It's way slower to construct an annotateline() object than creating a plain tuple or a list. This patch changes the internal data structure from row-based to columnar, so the decorate() function can be instant (i.e. no Python in hot loop.) For code readability, the outermost tuple is switched to an attr.s object instead. (original, row-based attr.s) $ hg annot mercurial/commands.py --time > /dev/null time: real 11.470 secs (user 11.400+0.000 sys 0.070+0.000) $ hg annot mercurial/commands.py --time --line-number > /dev/null time: real 39.590 secs (user 39.500+0.000 sys 0.080+0.000) (this patch, columnar) $ hg annot mercurial/commands.py --time > /dev/null time: real 11.780 secs (user 11.710+0.000 sys 0.070+0.000) $ hg annot mercurial/commands.py --time --line-number > /dev/null time: real 12.240 secs (user 12.170+0.000 sys 0.090+0.000) (cf. 4.3.3, row-based tuple) $ hg annot mercurial/commands.py --time --line-number > /dev/null time: real 19.540 secs (user 19.460+0.000 sys 0.080+0.000)

wireproto: explicitly track which requests are active We previously only tracked which requests are receiving. A misbehaving client could accidentally have multiple requests with the same ID in flight. We now explicitly track which request IDs are currently active. We make it illegal to receive a frame associated with a request ID that has already been dispatched. Differential Revision: https://phab.mercurial-scm.org/D2901

wireproto: use named arguments when passing around frame data Named arguments is easier to reason about compared to positional arguments. Especially when you have many positional arguments. Differential Revision: https://phab.mercurial-scm.org/D2900

wireproto: define attr-based classes for representing frames When frames only had 3 attributes, it was reasonable to represent them as a tuple. With them growing more attributes, it will be easier to pass them around as a more formal type. So let's define attr-based classes to represent frame headers and full frames. Differential Revision: https://phab.mercurial-scm.org/D2899