histedit: don't record labels for output that we will discard Differential Revision: https://phab.mercurial-scm.org/D10881

dog-raft: work with str-keyed opts throughout Differential Revision: https://phab.mercurial-scm.org/D10864

cmdutil: make resolvecommitoptions() work on str-keyed opts As with `checknotesize()`, I also changed to snake_case while at it, to help extensions a little. Differential Revision: https://phab.mercurial-scm.org/D10863

cmdutil: make amend() take str-keyed opts I couldn't think of a reasonable change to the signature here, so unfortunately it keeps the existing one. Differential Revision: https://phab.mercurial-scm.org/D10862

commit: keep opts dict str-keyed a bit longer Differential Revision: https://phab.mercurial-scm.org/D10861

dog-raft: keep opts dict str-keyed a bit longer Differential Revision: https://phab.mercurial-scm.org/D10860

cmdutil: make checknotesize() work on str-keyed opts Since this patch changes the behavior of the function, I consider it a bonus if the signature also changes so that extensions can detect which version they're dealing with (for the record, I don't have any such extensions). Therefore, I also dropped an unused `ui` argument and renamed the function to use snake_case. Differential Revision: https://phab.mercurial-scm.org/D10859

amend: work mostly with str-type **opts for simplicity Differential Revision: https://phab.mercurial-scm.org/D10880

revlog: use file read caching for sidedata The previous changeset extracted this caching logic from the revlog class into a new class. Adding a new instance of that class allows using the same logic for side data. Differential Revision: https://phab.mercurial-scm.org/D10879

revlog: Extract low-level random-access file read caching logic The `revlog` class does many things, among which fulfilling requests for arbitrary byte slices from the revlog "data file" by reading a larger chunk and caching it in memory, in order to reduce the number of system calls. This extracts that logic into a new class, so that it may later also be used for the side-data file (with another instance of that class). The copyright notice of the new file does not include a date or author name since such information tend not to be kept up-to-date: https://www.linuxfoundation.org/en/blog/copyright-notices-in-open-source-software-projects/ Differential Revision: https://phab.mercurial-scm.org/D10878

typing: disable warnings for a couple of Windows specific attributes Differential Revision: https://phab.mercurial-scm.org/D10870

typing: suppress a false error in mercurial/revlogutils/docket.py on py2 `ord()` wants bytes or str on py3, so I'm guessing it got confused by passing a single byte instead of a one byte string. But this seems to work on 2.7.18 anyway. Differential Revision: https://phab.mercurial-scm.org/D10876

transaction: simplify `undo.backupfiles` file creation with a variable This make the code shorter and clearer. (This is an opportunity improvement while looking at something next to that.) Differential Revision: https://phab.mercurial-scm.org/D10846

transaction: narrow the error filtering when failing to rename undo file Having inconsistent "undo" files can be quite serious so we narrow the error filtering to the intent that the comment explain. (This is an opportunity improvement while looking at something next to that.) Differential Revision: https://phab.mercurial-scm.org/D10845