There are a few places in the code that could be cleaned up:

1. There are defined variables that are never used
2. Some places where semicolon use is not consistent
3. There is another duplicate test case

https://github.com/mrennie/esprima/commit/6d2082d07a78997f7b7611cadb99796fea575a9b

All tests pass.

Good catch! Is there a way to tweak our ESLint configuration so that those are caught automatically as well?

I could investigate. The ESLInt in Orion is not stock - we have modified it and provide our own custom rules, but perhaps there are similar rules.

I opened issue 548 to track the ESLint updates (if any)

Issue 545: Code cleanup https://github.com/ariya/esprima/commit/6d2082d07a