microsoft / microsoft/TypeScript

Ignore __proto__

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Description

TypeScript Version: 2.2.0

Code:

{ __proto__: {} } as { [key: string]: string }

Expected behavior:
Ok

Actual behavior:
Type '{ __proto__: {}; }' cannot be converted to type '{ [key: string]: string; }'.

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

Start by reproducing the TypeScript 2.2.0 example { __proto__: {} } as { [key: string]: string } and trace how the type checker handles this object property during the assertion. Done means the example is accepted without weakening the expected index-signature checks.

Written by the indexing model from the issue text.

Assessment

Tech stack
typescript
Domain
compilers
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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