Improve detection for regexp/no-useless-assertion
#663
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Fixes #661.
The new condition for always accepting is relatively simple. It's just the previous check, but it accounts for edges properly and allows more assertions.
The complex part of this PR is the
isSingleCharacterAssertion
function. Implementing this function was surprisingly complex. Since we can't modify the AST, we have to handle some pretty complex cases. But even with those complex cases handled,isSingleCharacterAssertion
is still not perfect and will return false negatives at times. Fortunately, false negatives aren't a problem for us.