feat(codemode): expand standard library parity (#37943)

packages/codemode/test/stdlib.test.ts

@@ -2,11 +2,16 @@
  * Portions adapted from Test262 at revision 250f204f23a9249ff204be2baec29600faae7b75:
  * - test/built-ins/Date/value-to-primitive-result-non-string-prim.js
  * - test/built-ins/Date/value-to-primitive-result-string.js
+ * - test/built-ins/Date/prototype/toUTCString/format.js
+ * - test/built-ins/Date/prototype/toUTCString/invalid-date.js
+ * - test/built-ins/RegExp/prototype/exec/S15.10.6.2_A4_T8.js
  *
- * CodeMode does not support Symbol.toPrimitive, so these cases exercise the same Date-constructor primitive-result
+ * CodeMode does not support Symbol.toPrimitive, so the Date-constructor cases exercise the same primitive-result
  * handling through supported own valueOf and toString functions.
  *
  * Copyright (C) 2016 the V8 project authors. All rights reserved.
+ * Copyright (C) 2017 the V8 project authors. All rights reserved.
+ * Copyright 2009 the Sputnik authors. All rights reserved.
  * Test262 portions are governed by the BSD license in LICENSE.test262.
  */
 import { describe, expect, test } from "bun:test"
@@ -175,6 +180,25 @@ describe("Date", () => {
     expect(await value(`return typeof new Date(0)`)).toBe("object")
     expect(await value(`return new Date(0).nope === undefined`)).toBe(true)
   })
+
+  test("toUTCString and toGMTString use the native UTC format", async () => {
+    expect(
+      await value(`
+        const date = new Date(0)
+        return [
+          date.toUTCString(),
+          date.toGMTString(),
+          new Date(NaN).toUTCString(),
+          new Date("0020-01-01T00:00:00Z").toUTCString(),
+        ]
+      `),
+    ).toEqual([
+      "Thu, 01 Jan 1970 00:00:00 GMT",
+      "Thu, 01 Jan 1970 00:00:00 GMT",
+      "Invalid Date",
+      "Wed, 01 Jan 0020 00:00:00 GMT",
+    ])
+  })
 })
 
 describe("RegExp", () => {
@@ -211,6 +235,51 @@ describe("RegExp", () => {
     ).toEqual(["1", "22"])
   })
 
+  test("lastIndex is writable and exec coerces its stored value", async () => {
+    expect(
+      await value(`
+        const pattern = /(?:ab|cd)\\d?/g
+        pattern.lastIndex = "12"
+        const stored = [pattern.lastIndex, typeof pattern.lastIndex]
+        const match = pattern.exec("aacd2233ab12nm444ab42")
+        pattern.lastIndex = 0
+        return [stored, match[0], match.index, pattern.lastIndex, delete pattern.lastIndex]
+      `),
+    ).toEqual([["12", "string"], "ab4", 17, 0, false])
+  })
+
+  test("exec coerces CodeMode data objects assigned to lastIndex", async () => {
+    expect(
+      await value(`
+        const pattern = /a/g
+        pattern.lastIndex = {}
+        const stored = pattern.lastIndex
+        const match = pattern.exec("ba")
+        pattern.lastIndex = 10
+        const missed = pattern.exec("a")
+        return [stored, match.index, pattern.lastIndex, missed]
+      `),
+    ).toEqual([{}, 1, 0, null])
+  })
+
+  test("non-global exec and test coerce and preserve lastIndex", async () => {
+    expect(
+      await value(`
+        const execPattern = /a/
+        const execIndex = {}
+        execPattern.lastIndex = execIndex
+        const match = execPattern.exec("ba")
+
+        const testPattern = /a/
+        const testIndex = {}
+        testPattern.lastIndex = testIndex
+        const matched = testPattern.test("ba")
+
+        return [match.index, execPattern.lastIndex === execIndex, matched, testPattern.lastIndex === testIndex]
+      `),
+    ).toEqual([1, true, true, true])
+  })
+
   test("an unmatched string pattern returns null", async () => {
     expect(await value(`return "abc".match(/\\d/)`)).toBeNull()
   })