| /** | |
| * Structural not-implemented stubs: a replaced module must expose every symbol | |
| * its importers name (a missing CommonJS symbol degrades to `undefined` at call | |
| * time instead of failing at link time), and every one of those symbols must | |
| * report exactly what is unavailable when it is finally called. | |
| */ | |
| /** | |
| * Build a function that throws naming its module and symbol. The refusal is | |
| * also written to the console before it propagates: callers routinely swallow | |
| * these errors far from their cause, and the console line is what places the | |
| * failure while debugging a worker session. | |
| * | |
| * `Face` is the Node declaration this stub stands in for, so the replaced module | |
| * publishes the type its importers compile against. The value is one throwing | |
| * function whatever that declaration says: a caller reaches the throw before any | |
| * declared parameter, return value, or `new` result exists, so the assertion | |
| * below cannot be observed as a lie. It is a function expression rather than an | |
| * arrow because a stub standing in for a class must refuse under `new` too, and | |
| * an arrow has no construct behavior to reach. | |
| * @param module - module specifier being stubbed. | |
| * @param symbol - exported symbol name. | |
| * @returns the throwing stand-in, typed as the member it replaces. | |
| */ | |
| // eslint-disable-next-line @typescript-eslint/no-unnecessary-type-parameters -- only the return position carries the Node declaration | |
| export function notImplementedFail<Face = (...args: never[]) => never>(module: string, symbol: string): Face { | |
| return (function refuse(): never { | |
| throw notAvailableError(module, symbol) | |
| }) as Face | |
| } | |
| /** | |
| * Build the refusal error and write it to the console first, for stubs that | |
| * cannot be a plain throwing function (constructors, methods on structural | |
| * fakes). | |
| * @param module - module specifier being stubbed. | |
| * @param symbol - unavailable member, named as the importer sees it. | |
| * @returns the error to throw. | |
| */ | |
| export function notAvailableError(module: string, symbol: string): Error { | |
| const message = `web-preview: ${module}.${symbol} is not available in the worker host` | |
| console.error(message) | |
| return new Error(message) | |
| } | |