merge with stable

byteify-strings: add cli argument to handle `attr*()` when they are methods Certain code bases have useful utils that wrap the builtin functions, and are called like `util.setattr`.

byteify-strings: simplify default value for `--treat-as-kwargs`

byteify-strings: add --treat-as-kwargs argument to handle kwargs-like objects This argument will help extensions move to Python 3 as keyword arguments should not be byte-prefixed. Most of the time, code bases will call this object `kwargs`, but other conventions exist like `opts`, so it should make sense to allow for custom names. This is a best effort solution that does minimal static checking; cases like `options = [o for o in ('a', 'b', 'c') if kwargs.get(o)]` and other just as complicated will not be detected.

byteify-strings: add helpers to check for item access or method call These helpers will be used in a future patch, split for ease of review.

byteify-strings: add support for ignore comments Our simple token analysis is sometimes not clever enough, we need to be able to turn off our script for parts of the code. This change introduces three special comments: - `#no-py3-transform` to tell `byteify-strings` ignore the next line - `#py3-transform: off` to ignore everything until the end of the file - `#py3-transform: on` to stop ignoring The last two can be particularly useful within Python 2/3 compatibility files.

byteify-strings: handle triple quoted strings if they are not docstrings As with anything in this script, this is a best effort approach. Most of the time, when a triple quoted string is assigned to something, it's not a docstring.