benjamn / benjamn/recast

Recast printer not preserving identity with inline comments

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#296 2 comments 0 reactions 0 assignees View on GitHub
Dominant language
TypeScript
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Description

The following assertion fails, as the parentheses are incorrectly moved by the recast printer, breaking the guaranteed identity of non-modified code:

```
const recast = require('recast');
const assert = require('assert');

const input = 'foo + (/** @type {number} */(bar) - baz);'
const output = recast.print(recast.parse(input)).code;
assert.equal(input, output);
```

Actual output:
`foo + (/** @type {number} */(bar - baz));`

Expected output:
`foo + (/** @type {number} */(bar) - baz);'`

This actually breaks my build, as the closure compiler cast is now being applied to the result of `bar - baz` instead of solely on `bar`.

Contributor guide

No contributing guide indexed for this repository

Research direction

Start with the provided recast.parse and recast.print reproduction, then inspect the printer handling of inline comments and parentheses. Done means the assertion passes and the input remains unchanged when printing this code.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript
Domain
tooling
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
48/100

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