typing: add `from __future__ import annotations` to most files
Now that py36 is no longer supported, we can postpone annotation evaluation.
This means that the quoting is usually optional (for things imported under the
guard of `if typing.TYPE_CHECKING:` to avoid circular imports), and there's less
overhead on startup[1].
There may be some missing here. I backed out
6000f5b25c9b (which removed the
`from __future__ import ...` that was supporting py2), reverted the changes in
`contrib/`, `doc/`, and `tests/`, and then ran:
$ hg status -n --change . | \
xargs sed -i -e 's/from __future__ import .*$/from __future__ import annotations/'
There were some minor tweaks needed when reviewing (mostly making the spacing
around the import consistent, and `mercurial/testing/__init__.py` had a
multiline import that wasn't fully rewritten.
[1] https://docs.python.org/3/whatsnew/3.7.html#pep-563-postponed-evaluation-of-annotations
format: add many "missing" comma
Black was not adding them until the next changeset introduced a bunch of `from
__future__ import annotations` to most file. Since it make the next changeset
hard to read we introduce them in advance.
typing: simplify archive.gz writing and drop a few pytype suppressions
I was waiting until 3.8 to use `Literal` to fix this, but there's also the ":"
and "|" characters that are passed along here, meant only for the non-gz archive
types. But manipulating what the local caller passes is silly- we know we're
writing, so just open it for writing. As an added bonus, PyCharm stops flagging
the call too (since it doesn't know about pytype suppression comments).
typing: explicitly set the return type of `_InnerRevLog.raw_text()`
Somewhere between
cd72a88c5599 and
2fd44b3dcc33, pytype changed the return type
from `Tuple[_T1, Any, bool]` to `Any`. Both are wrong. `mdiff.patches()` is an
alias for `mpatch.patches()`, which is selected via module policy (and breaks
the ability to infer the types). However, `cext`, `cffi`, and `pure`
implementations all agree it returns bytes.
typing: add explicit hints for recent pytype regressions
Somewhere between
454feddab720 and
cd72a88c5599, pytype changed how it inferred
the return type in `extdiff.py` from
Tuple[Any, List[Tuple[bytes, Any, os.stat_result]]]
to
Tuple[Any, List[nothing]]
It also changed the return type in `archival.py` from `Any` to `NoReturn`. Fix
those up, and also the obvious parameter types while we're here.
revlog: use the method to check if the revlog is being written to
This was probably fine, but it could become not fine at some point.
revlog: add an early return for getting sidedata
No point in trying to fetch sidedata if there isn't a sidedata file.
revlog: simplify rawtext return value
We're always returning a tuple even though only the raw text is being used,
and we're rebuilding another tuple again higher.
As a bonus, this will remove one tuple creation and deletion
per `raw_text` call, hence fewer gc calls, etc.