puppeteer-core
Version:
A high-level API to control headless Chrome over the DevTools Protocol
78 lines • 2.36 kB
JavaScript
/**
* @license
* Copyright 2023 Google Inc.
* SPDX-License-Identifier: Apache-2.0
*/
const createdFunctions = new Map();
/**
* Creates a function from a string.
*
* @internal
*/
export const createFunction = (functionValue) => {
let fn = createdFunctions.get(functionValue);
if (fn) {
return fn;
}
fn = new Function(`return ${functionValue}`)();
createdFunctions.set(functionValue, fn);
return fn;
};
/**
* @internal
*/
export function stringifyFunction(fn) {
let value = fn.toString();
try {
new Function(`(${value})`);
}
catch (err) {
if (err.message.includes(`Refused to evaluate a string as JavaScript because 'unsafe-eval' is not an allowed source of script in the following Content Security Policy directive`)) {
// The content security policy does not allow Function eval. Let's
// assume the value might be valid as is.
return value;
}
// This means we might have a function shorthand (e.g. `test(){}`). Let's
// try prefixing.
let prefix = 'function ';
if (value.startsWith('async ')) {
prefix = `async ${prefix}`;
value = value.substring('async '.length);
}
value = `${prefix}${value}`;
try {
new Function(`(${value})`);
}
catch {
// We tried hard to serialize, but there's a weird beast here.
throw new Error('Passed function cannot be serialized!');
}
}
return value;
}
/**
* Replaces `PLACEHOLDER`s with the given replacements.
*
* All replacements must be valid JS code.
*
* @example
*
* ```ts
* interpolateFunction(() => PLACEHOLDER('test'), {test: 'void 0'});
* // Equivalent to () => void 0
* ```
*
* @internal
*/
export const interpolateFunction = (fn, replacements) => {
let value = stringifyFunction(fn);
for (const [name, jsValue] of Object.entries(replacements)) {
value = value.replace(new RegExp(`PLACEHOLDER\\(\\s*(?:'${name}'|"${name}")\\s*\\)`, 'g'),
// Wrapping this ensures tersers that accidentally inline PLACEHOLDER calls
// are still valid. Without, we may get calls like ()=>{...}() which is
// not valid.
`(${jsValue})`);
}
return createFunction(value);
};
//# sourceMappingURL=Function.js.map