2022-03-28 23:10:17 -07:00

68 lines
2.4 KiB
TypeScript

/**
* Copyright (c) Microsoft Corporation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import { serializeAsCallArgument, parseEvaluationResultValue } from '../common/utilityScriptSerializers';
export class UtilityScript {
evaluate(isFunction: boolean | undefined, returnByValue: boolean, expression: string, argCount: number, ...argsAndHandles: any[]) {
const args = argsAndHandles.slice(0, argCount);
const handles = argsAndHandles.slice(argCount);
const parameters = args.map(a => parseEvaluationResultValue(a, handles));
let result = globalThis.eval(expression);
if (isFunction === true) {
result = result(...parameters);
} else if (isFunction === false) {
result = result;
} else {
// auto detect.
if (typeof result === 'function')
result = result(...parameters);
}
return returnByValue ? this._promiseAwareJsonValueNoThrow(result) : result;
}
jsonValue(returnByValue: true, value: any) {
// Special handling of undefined to work-around multi-step returnByValue handling in WebKit.
if (Object.is(value, undefined))
return undefined;
return serializeAsCallArgument(value, (value: any) => ({ fallThrough: value }));
}
private _promiseAwareJsonValueNoThrow(value: any) {
const safeJson = (value: any) => {
try {
return this.jsonValue(true, value);
} catch (e) {
return undefined;
}
};
if (value && typeof value === 'object' && typeof value.then === 'function') {
return (async () => {
// By using async function we ensure that return value is a native Promise,
// and not some overridden Promise in the page.
// This makes Firefox and WebKit debugging protocols recognize it as a Promise,
// properly await and return the value.
const promiseValue = await value;
return safeJson(promiseValue);
})();
}
return safeJson(value);
}
}
module.exports = UtilityScript;