`default` keyword is offered in expression-bodied arrow function completions

Bug Report

Search Terms

• arrow function completion
• default keyword completion
• expression-bodied arrow function
• keyword completions
• completionListAtEndOfWordInArrowFunction

Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about keyword completions in expression-bodied arrow function contexts.

Playground Link

Playground link with relevant code: https://www.typescriptlang.org/play?#code/PTAEFkE9QYwewCYFNQHM5IM6gBZIE5JA

Code

(d, defaultIsAnInvalidParameterName) => d

(d, defaultIsAnInvalidParameterName) => default

Actual behavior

At the expression-bodied arrow function completion position, default is offered as a keyword completion.

Expected behavior

default should not appear as a keyword completion in expression-bodied arrow function expression context.

Additional information about the issue

There are already nearby fourslash tests that appear to acknowledge this behavior as undesirable:

• tests/cases/fourslash/completionListAtEndOfWordInArrowFunction02.ts
• tests/cases/fourslash/completionListAtEndOfWordInArrowFunction03.ts

I also traced the completion path locally and confirmed the keyword currently comes from the generic FunctionLikeBodyKeywords filtering path.

Start with the completion path described in the issue and the generic FunctionLikeBodyKeywords filtering path. Read tests/cases/fourslash/completionListAtEndOfWordInArrowFunction02.ts and tests/cases/fourslash/completionListAtEndOfWordInArrowFunction03.ts, then use the linked Playground example to reproduce the completion. Done means default is absent in expression-bodied arrow function expression completions and the relevant fourslash coverage passes.