The current pretty conservative approach is to avoid merging parse states which
would cause a pair tokens to co-exist for the first time in any parse state,
where the two tokens can start with the same character and at least one of the
tokens can contain a character which is part of the grammar's separators.
* Remove remnants of templatized remove_duplicate_states function
* Rename recovery_tokens function to get_compatible_tokens and augment it
also compute pairs of tokens which could potentially be incompatible
If we already have a stack version in which, for example,
a `function_call` is skipped, don't create another stack
version in which that `function_call` is reduced to an
`expression`, and then the `expression` is skipped. That
doesn't improve the error recovery at all, but adds to the
branching factor of the parse stack and makes things harder
to debug.
They used to be called e.g. `ts_language_python`. Now that there
are APIs that deal with the `TSLanguage` objects themselves, such
as `ts_language_symbol_count`, the old names were a little confusing.
There was an error in the way that we calculate the reference
scope sequences that are used as the basis for assertions about
changed ranges in randomized tests. The error caused some
characters' scopes to not be checked. This corrects the reference
implementation and fixes a previously uncaught bug in the
implementation of `tree_path_get_changed_ranges`.
Previously, when iterating over the old and new trees, we would
only perform comparisons of visible nodes. This resulted in a failure
to do any comparison for portions of the text in which there were
trailing invisible child nodes (e.g. trailing `_line_break` nodes
inside `statement` nodes in the JavaScript grammar).
Now, we additionally perform comparisons at invisible leaf nodes,
based on their lowest visible ancestor.
Tokens that are defined in the grammar's rules may now be included in the
externals list also, so that external scanners can check if they are valid
lookaheads or not, and if so, can return them to the parser if needed.