- numeric literals are now formatted by _Black_ (452, 461, 464, 469):
- numeric literals are normalized to include `_` separators on Python 3.6+ code
- added `--skip-numeric-underscore-normalization` to disable the above behavior and
leave numeric underscores as they were in the input
- code with `_` in numeric literals is recognized as Python 3.6+
- most letters in numeric literals are lowercased (e.g., in `1e10`, `0x01`)
- hexadecimal digits are always uppercased (e.g. `0xBADC0DE`)
- added `blackd`, see
[its documentation](https://github.com/psf/black/blob/18.9b0/README.md#blackd) for
more info (349)
- adjacent string literals are now correctly split into multiple lines (463)
- trailing comma is now added to single imports that don't fit on a line (250)
- cache is now populated when `--check` is successful for a file which speeds up
consecutive checks of properly formatted unmodified files (448)
- whitespace at the beginning of the file is now removed (399)
- fixed mangling [pweave](http://mpastell.com/pweave/) and
[Spyder IDE](https://www.spyder-ide.org/) special comments (#532)
- fixed unstable formatting when unpacking big tuples (267)
- fixed parsing of `__future__` imports with renames (389)
- fixed scope of ` fmt: off` when directly preceding `yield` and other nodes (385)
- fixed formatting of lambda expressions with default arguments (468)
- fixed `async for` statements: _Black_ no longer breaks them into separate lines (372)
- note: the Vim plugin stopped registering `,=` as a default chord as it turned out to
be a bad idea (415)