parser: resolve ambiguity where both prefix and primary actions are defined
If both actions are defined, a primary-expression action is accepted only if
the next token never starts new term. For example,
parsed as primary expression:
":" # next token 'end' has no action
"(:)" # next token ')' has no action
":+y" # next token '+' is infix operator
parsed as prefix operator:
":y" # next token 'y' is primary expression
":-y" # next token '-' is prefix operator
This is mostly the same resolution as the infix/suffix rules.
--- a/mercurial/parser.py Sun Jul 05 12:02:13 2015 +0900
+++ b/mercurial/parser.py Sun Jul 05 12:09:27 2015 +0900
@@ -49,9 +49,9 @@
return expr
def _parse(self, bind=0):
token, value, pos = self._advance()
- # handle prefix rules on current token
+ # handle prefix rules on current token, take as primary if unambiguous
primary, prefix = self._elements[token][1:3]
- if primary:
+ if primary and not (prefix and self._hasnewterm()):
expr = (primary, value)
elif prefix:
expr = (prefix[0], self._parseoperand(*prefix[1:]))