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/*
* Copyright (C) 2021-2022 Kristóf Marussy <kristof@marussy.com>
*
* This file is part of Sophie.
*
* Sophie is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, version 3.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
* SPDX-License-Identifier: AGPL-3.0-only
*/
/**
* Simulates a function defined in native code, i.e., one with
* `[native code]` in its `toString`.
*
* @param name The name of the function.
* @param f The function to transform.
* @return The transformed function.
*/
export function simulateNativeFunction<T, P extends unknown[]>(
name: string,
f: (this: null, ...args: P) => T,
): (...args: P) => T {
// Bound functions say `[native code]`, but unfortunately they omit the function name:
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/toString#description
// The type of `f` contains type variables, so we need some magic type casting.
const boundFunc = f.bind(null as ThisParameterType<typeof f>);
Object.defineProperty(boundFunc, 'name', {
configurable: true,
enumerable: false,
value: name,
writable: false,
});
return boundFunc;
}
/**
* Simulates a native class available on `globalThis`.
*
* @param name The name of the class.
* @param constructor The constructor function. Must already be a constructor (a named `function`).
* @param properties The properties to define on the prototype.
*/
export function simulateNativeClass(
name: string,
constructor: () => void,
properties: PropertyDescriptorMap,
) {
Object.defineProperties(constructor.prototype, {
[Symbol.toStringTag]: {
configurable: true,
enumerable: false,
value: name,
writable: false,
},
...properties,
});
const simulatedConstructor = simulateNativeFunction(name, constructor);
Object.defineProperty(globalThis, name, {
configurable: true,
enumerable: true,
value: simulatedConstructor,
writable: true,
});
return simulatedConstructor;
}
/**
* Defines a property on the prototype of an object.
*
* Only use this with singleton objects, e.g., `window.navigator`.
*
* @param o The object to modify. Must be a singleton.
* @param property The key of the property being defined or modified.
* @param attributes The descriptor of the property being defined or modified.
*/
export function defineProtoProperty(
o: object,
property: PropertyKey,
attributes: PropertyDescriptor,
): void {
Object.defineProperty(Object.getPrototypeOf(o), property, attributes);
}
/**
* Deletes a property from the prototype of an object.
*
* Only use this with singleton objects, e.g., `window.navigator`.
*
* @param o The object to modify. Must be a singleton.
* @param property The key of the property being deleted.
*/
export function deleteProtoProperty(o: object, property: PropertyKey): void {
Reflect.deleteProperty(Object.getPrototypeOf(o), property);
}
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