Add auto-completion results to CSSStyleDeclaration.{setProperty,removeProperty}

Search Terms

setProperty

Suggestion

CSSStyleDeclaration.setProperty(propertyName, value, priority); is currently typed as setProperty(property: string, value: string | null, priority?: string | undefined): void.
There is a specific set of defined properties in CSS: https://www.w3.org/TR/CSS/#properties It would be great if this specific list of properties could be added to the definition, such that auto-completion would show the allowed values.

(The same is true for https://developer.mozilla.org/en-US/docs/Web/API/CSSStyleDeclaration/removeProperty so this feature request applies to that method as well)

For backwards compatible reasons (and to be spec-compliant), a string overload would remain. That's because the following is legal, albeit a noop:

element.style.setProperty('non-existent', 'something');

Use Cases

Improved editor experience for style APIs.

Examples

With my cursor at |, ask for the auto-completions. The expected behavior would be to show the list of accepted properties, similar to how document.createElement works.

element.style.setProperty('|

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

まず CSSStyleDeclaration.setProperty と removeProperty の定義から始め、補完の動作の比較対象として既存の document.createElement の型定義を使用します。既知の CSS プロパティ名が補完結果に表示され、後方互換性のために任意の文字列も引き続き受け入れられるようになれば、作業は完了です。