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incorrect-translator-usage

Require translation bundles returned by translator.load() to be stored under an extractor-recognized name (e.g. trans, this.trans, this._trans, props.trans, this.props.trans).

Why​

JupyterLab collects translatable strings statically with a gettext-based extractor. The extractor only recognizes translation calls made through a small set of names:

  • trans
  • this.trans
  • this._trans
  • this.props.trans
  • props.trans

Calling __() (or any other bundle method) directly on the result of translator.load(), or storing the bundle under any other name, silently hides those strings from the extractor: the code still runs, but the strings never end up in language packs and stay untranslated. See Rules.

Rule details​

The rule reports:

  • A translation bundle method (__, _n, _p, _np, gettext, ngettext, pgettext, npgettext, dcnpgettext) called directly on the result of a <translator>.load(...) call.
  • The result of <translator>.load(...) stored under a name the extractor does not recognize — a variable or object property not named trans, or a member target other than this.trans, this._trans, props.trans or this.props.trans.
  • Destructuring the result of <translator>.load(...).

An object counts as a translator when its name contains translator (for example translator, this._translator, props.translator or nullTranslator). A chained bundle method or an unrecognized target only triggers the rule when the underlying .load(...) is called on such a translator; an unrelated .load(...) API is left alone. Passing the bundle directly to a function or returning it is not reported: the receiver is responsible for storing it under a recognized name.

Incorrect​

// Chained call — the string is never extracted
translator.load('jupyterlab').__('some-string');

// Unrecognized variable name
const someNameButNotTrans = translator.load('jupyterlab');
someNameButNotTrans.__('some-string');

// Unrecognized instance property name
this._bundle = translator.load('mydomain');

Correct​

const trans = translator.load('jupyterlab');
trans.__('some-string');

// In a class
this._trans = translator.load('mydomain');
this._trans.__('some-string');

Options​

This rule has no options.