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.
--- a/contrib/byteify-strings.py Fri Aug 02 09:55:32 2019 +0200
+++ b/contrib/byteify-strings.py Fri Aug 02 10:10:23 2019 +0200
@@ -92,6 +92,36 @@
except IndexError:
break
+ def _isitemaccess(j):
+ """Assert the next tokens form an item access on `tokens[j]` and that
+ `tokens[j]` is a name.
+ """
+ try:
+ return (
+ tokens[j].type == token.NAME
+ and _isop(j + 1, '[')
+ and tokens[j + 2].type == token.STRING
+ and _isop(j + 3, ']')
+ )
+ except IndexError:
+ return False
+
+ def _ismethodcall(j, *methodnames):
+ """Assert the next tokens form a call to `methodname` with a string
+ as first argument on `tokens[j]` and that `tokens[j]` is a name.
+ """
+ try:
+ return (
+ tokens[j].type == token.NAME
+ and _isop(j + 1, '.')
+ and tokens[j + 2].type == token.NAME
+ and tokens[j + 2].string in methodnames
+ and _isop(j + 3, '(')
+ and tokens[j + 4].type == token.STRING
+ )
+ except IndexError:
+ return False
+
coldelta = 0 # column increment for new opening parens
coloffset = -1 # column offset for the current line (-1: TBD)
parens = [(0, 0, 0)] # stack of (line, end-column, column-offset)