Issue: TypeScript autocomplete for template literal types ignores user's Quote Style preference

🔎 Search Terms

List of keywords : "double", "quote", "preference", "style", "autcomplete", "template", "literral"

🕗 Version & Regression Information

TS Version : 6.0.3 or 7.0-rc

⏯ Playground Link

https://www.typescriptlang.org/play/?#code/C4TwDgpgBAKghgIwDYQHJwLbQLxQOTACMeUAPvsAEx4DcAUKJFAMID2SArhgHbpZS48ASwAmJcngBucThFoNw0eMghtOPAVAAGAEgDeylHwgBfAHT61XXplNb6jaAClWQ7pr10oUVtwBcUAAKcABOwEIyADwAShAAxqwhIpGGquzWADSwiChWPAB8+fQm9AncAM7AUMAQlQEubh5ePv5Qnt5QzSZ0JUA

💻 Code

type TableName = 't1' | 't2';
type ColumnName = 'id' | 'value';
type TableColumn = `${TableName}.${ColumnName}`;

type Join = {
  on: Partial<Record<TableColumn, TableColumn>>;
};

const test: Join = {
  on: {
    // Trigger autocomplete inside the object
  }
};

🙁 Actual behavior

The key is inserted using double quotes (e.g., "t1.id": ...), overriding the user's preference for single quotes.

🙂 Expected behavior

The key should be inserted using the quote style defined in the editor's preferences (e.g., single quotes if 'single' is selected).

Additional information about the issue

When using template literal types as keys in a Record or object mapping, the TypeScript language service's autocomplete functionality consistently forces double quotes (") when inserting the suggested keys, regardless of the user's configured javascript.preferences.quoteStyle or typescript.preferences.quoteStyle settings.

https://github.com/user-attachments/assets/e562b5ab-bbd7-48bd-96f8-a9181f03ba2e

This behavior is inconsistent with how standard string keys or property names are handled and complicates code consistency when working with complex template literal types in type-safe mappings.

エディターの引用符設定をシングルクォートにした状態で、リンク先の TypeScript Playground にある template-literal Record の例を再現します。まず、オブジェクトキーに対する TypeScript language service のオートコンプリート経路を追跡し、次に、候補として提示されたキーを受け入れたときに、設定された引用符スタイルが JavaScript と TypeScript の両方の設定で維持されることを確認します。