feat(executioncontext): support bigints transferring (#4016)

Refs: https://chromedevtools.github.io/devtools-protocol/tot/Runtime#type-UnserializableValue

docs/api.md

@@ -1245,7 +1245,7 @@ List of all available devices is available in the source code: [DeviceDescriptor
 
 If the function passed to the `page.evaluate` returns a [Promise], then `page.evaluate` would wait for the promise to resolve and return its value.
 
-If the function passed to the `page.evaluate` returns a non-[Serializable] value, then `page.evaluate` resolves to `undefined`.
+If the function passed to the `page.evaluate` returns a non-[Serializable] value, then `page.evaluate` resolves to `undefined`. DevTools Protocol also supports transferring some additional values that are not serializable by `JSON`: `-0`, `NaN`, `Infinity`, `-Infinity`, and bigint literals.
 
 Passing arguments to `pageFunction`:
 ```js
@@ -2031,7 +2031,7 @@ for (const worker of page.workers())
 
 If the function passed to the `worker.evaluate` returns a [Promise], then `worker.evaluate` would wait for the promise to resolve and return its value.
 
-If the function passed to the `worker.evaluate` returns a non-[Serializable] value, then `worker.evaluate` resolves to `undefined`.
+If the function passed to the `worker.evaluate` returns a non-[Serializable] value, then `worker.evaluate` resolves to `undefined`. DevTools Protocol also supports transferring some additional values that are not serializable by `JSON`: `-0`, `NaN`, `Infinity`, `-Infinity`, and bigint literals.
 
 Shortcut for [(await worker.executionContext()).evaluate(pageFunction, ...args)](#executioncontextevaluatepagefunction-args).
 
@@ -2498,7 +2498,7 @@ Gets the full HTML contents of the frame, including the doctype.
 
 If the function passed to the `frame.evaluate` returns a [Promise], then `frame.evaluate` would wait for the promise to resolve and return its value.
 
-If the function passed to the `frame.evaluate` returns a non-[Serializable] value, then `frame.evaluate` resolves to `undefined`.
+If the function passed to the `frame.evaluate` returns a non-[Serializable] value, then `frame.evaluate` resolves to `undefined`. DevTools Protocol also supports transferring some additional values that are not serializable by `JSON`: `-0`, `NaN`, `Infinity`, `-Infinity`, and bigint literals.
 
 ```js
 const result = await frame.evaluate(() => {
@@ -2817,6 +2817,8 @@ Besides pages, execution contexts can be found in [workers](https://developer.mo
 
 If the function passed to the `executionContext.evaluate` returns a [Promise], then `executionContext.evaluate` would wait for the promise to resolve and return its value.
 
+If the function passed to the `executionContext.evaluate` returns a non-[Serializable] value, then `executionContext.evaluate` resolves to `undefined`. DevTools Protocol also supports transferring some additional values that are not serializable by `JSON`: `-0`, `NaN`, `Infinity`, `-Infinity`, and bigint literals.
+
 ```js
 const executionContext = await page.mainFrame().executionContext();
 const result = await executionContext.evaluate(() => Promise.resolve(8 * 7));

lib/ExecutionContext.js

@@ -127,6 +127,8 @@ class ExecutionContext {
      * @this {ExecutionContext}
      */
     function convertArgument(arg) {
+      if (typeof arg === 'bigint') // eslint-disable-line valid-typeof
+        return { unserializableValue: `${arg.toString()}n` };
       if (Object.is(arg, -0))
         return { unserializableValue: '-0' };
       if (Object.is(arg, Infinity))

lib/helper.js

@@ -66,6 +66,8 @@ class Helper {
   static valueFromRemoteObject(remoteObject) {
     assert(!remoteObject.objectId, 'Cannot extract value when objectId is given');
     if (remoteObject.unserializableValue) {
+      if (remoteObject.type === 'bigint' && typeof BigInt !== 'undefined')
+        return BigInt(remoteObject.unserializableValue.replace('n', ''));
       switch (remoteObject.unserializableValue) {
         case '-0':
           return -0;

test/evaluation.spec.js

@@ -23,6 +23,8 @@ try {
   asyncawait = false;
 }
 
+const bigint = typeof BigInt !== 'undefined';
+
 module.exports.addTests = function({testRunner, expect}) {
   const {describe, xdescribe, fdescribe} = testRunner;
   const {it, fit, xit, it_fails_ffox} = testRunner;
@@ -33,6 +35,10 @@ module.exports.addTests = function({testRunner, expect}) {
       const result = await page.evaluate(() => 7 * 3);
       expect(result).toBe(21);
     });
+    (bigint ? it : xit)('should transfer BigInt', async({page, server}) => {
+      const result = await page.evaluate(a => a, BigInt(42));
+      expect(result).toBe(BigInt(42));
+    });
     it('should transfer NaN', async({page, server}) => {
       const result = await page.evaluate(a => a, NaN);
       expect(Object.is(result, NaN)).toBe(true);
@@ -135,6 +141,10 @@ module.exports.addTests = function({testRunner, expect}) {
       expect(result).not.toBe(object);
       expect(result).toEqual(object);
     });
+    (bigint ? it : xit)('should return BigInt', async({page, server}) => {
+      const result = await page.evaluate(() => BigInt(42));
+      expect(result).toBe(BigInt(42));
+    });
     it('should return NaN', async({page, server}) => {
       const result = await page.evaluate(() => NaN);
       expect(Object.is(result, NaN)).toBe(true);

tsconfig.json

@@ -3,7 +3,7 @@
     "noEmit": true,
     "allowJs": true,
     "checkJs": true,
-    "target": "es2017"
+    "target": "ESNext"
   },
   "include": [
     "lib"