Fix the following issue:
Separator DSL methods produce incorrect lookahead / possible tokens
When a rule uses the separator variants of the repetition DSL methods (MANY_SEP / AT_LEAST_ONE_SEP), the computation of the possible next tokens / lookahead paths gives wrong results.
For example, given a rule along the lines of:
this.RULE("list", () => {
this.MANY_SEP({
SEP: Comma,
DEF: () => { this.CONSUME(Identifier) }
})
})
After consuming an Identifier, the set of possible following tokens should include the separator (Comma) as one of the options (since the repetition may continue), in addition to whatever can follow the rule. In practice the separator is missing / not produced correctly by the path computation, which then breaks downstream features that rely on it (syntactic content assist, lookahead, etc.).
The non-separator variants (MANY / AT_LEAST_ONE) behave correctly for the same shape of grammar — the problem is specific to the *_SEP DSL methods.
Could the path / lookahead computation be fixed so that separator repetition methods produce the same kind of correct results as their non-separator counterparts?