/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at
http://mozilla.org/MPL/2.0/. */
// This JS module contains shared functionality for the generated UniFFI JS
// code.
// TypeError for UniFFI calls
//
// This extends TypeError to add support for recording a nice description of
// the item that fails the type check. This is especially useful for invalid
// values nested in objects/arrays/maps, etc.
//
// To accomplish this, the FfiConverter.checkType methods of records, arrays,
// maps, etc. catch UniFFITypeError, call `addItemDescriptionPart()` with a
// string representing the child item, then re-raise the exception. We then
// join all the parts together, in reverse order, to create item description
// strings like `foo.bar[123]["key"]`
export class UniFFITypeError extends TypeError {
constructor(reason) {
// our `message` getter isn't invoked in all cases, so we supply a default
// to the `TypeError` constructor.
super(reason);
this.reason = reason;
this.itemDescriptionParts = [];
}
addItemDescriptionPart(part) {
this.itemDescriptionParts.push(part);
this.updateMessage();
}
itemDescription() {
const itemDescriptionParts = [...this.itemDescriptionParts];
itemDescriptionParts.reverse();
return itemDescriptionParts.join("");
}
updateMessage() {
this.message = `${this.itemDescription()}: ${this.reason}`;
}
}
