microsoft / microsoft/TypeScript

Trivia ownership documentation seems to be incorrect

Open
#58,332 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Docs
Dominant language
Go
Stars
111k
Forks
14.3k
Avg merge
1d 19h
Merged PRs (30d)
117

Description

Acknowledgement
  • I acknowledge that issues using this template may be closed without further explanation at the maintainer's discretion.
Comment

Referencing the #1678 issue and the ast-trivia: trivia ownership in the typescript-book, there seems to be an error in explanation:

in the issue @mhegazy mentions:

one thing that is different from the Roslyn notion of trivia, is we do not have trailing trivia. all triva in TypeScript is leading. so for instance [...]

in the same issue and in the wiki book however the following info is given:

In General:

  • A token owns any trivia after it on the same line upto the next token.
  • Any comment after that line is associated with the following token.

So from the first cite I understand as if token owns any trivia before it up to the previous token ([trivia of A][token A]... that's why end-of-file token is always present) which seems to be the correct explanation, while the second cite describes that a token owns the trivia after it up to next token in the same line, which would mean that A has trailing trivia, thus not true in TS — albeit true for Roslyn.

[token A][trivia owned by A]<nl>
[trivia owned by B]
[token B]

Unless there is some misconception of what "owned" trivia means, but imo the second cite is incorrect.

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Open docs/compiler/ast-trivia.md at the “trivia ownership” section and compare its wording with issue #1678 and the cited TypeScript behavior. Update the explanation so ownership is consistent with the leading-trivia model described in the issue, then verify that the included examples no longer imply trailing trivia.

Written by the indexing model from the issue text.

Assessment

Tech stack
typescript
Domain
documentation
Issue type
Documentation
Difficulty
1/5
Estimated time
Under an hour
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
48/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.