fix(codemode): destructure object patterns from primitives and convert Date components through ToPrimitive (#51239)

2026-10-16 10:30:01 +08:00 · 2026-09-24 19:32:19 -05:00
parent e8b3e19e85
commit e23d89c9a9
6 changed files with 156 additions and 64 deletions
@@ -85,8 +85,9 @@ ultimate source of truth. Upstream test262 files run verbatim from `test/test262
 - [x] Array binding and assignment destructuring from strings, Maps, Sets, URLSearchParams, custom synchronous
      iterators, and synchronous generators, including stepwise elisions/rest and `IteratorClose` on early completion
      or binding/default failure.
- [ ] Object destructuring from primitives follows ToObject (`const { length } = "abc"`, `const {} = 1`); non-object
-      sources are rejected.
+- [x] Object destructuring from primitives follows ToObject: `const { length } = "abc"` is `3`, `const { toFixed } = 1`
+      finds the built-in, `const {} = 1` is a no-op, and a rest element copies a string's indexes (`{ 1: "y", 2: "z" }`).
+      Only `null` and `undefined` sources throw (`Cannot destructure null as it is null.`).
 - [x] Destructuring reads through the prototype chain like member access: `const { constructor } = error` and
      `const { slice } = values` find the inherited built-in.
 - [x] Any assignment target as a `for...in` head, like `for...of`: `for (x.y in obj)`, `for (a[i++] in obj)`, and
@@ -240,9 +241,9 @@ ultimate source of truth. Upstream test262 files run verbatim from `test/test262
      throws: `{ valueOf() { return 7 } } * 2` is `14`, `` `${{ toString() { return "x" } }}` `` is `"x"`, and
      `[1, 2]` with `arr.toString = () => "x"` makes `arr + ""` `"x"`. Dates keep their `Symbol.toPrimitive`
      behavior (`date + 1` concatenates, `date - date` subtracts).
- [ ] ToPrimitive elsewhere: multi-argument `Date` construction, `Date.UTC`, `Error.prototype.toString` on an object
-      `message`, and numeric built-in arguments outside `Math` (`at`, `indexOf` start, `toFixed` digits) still use the
-      built-in form (`NaN`, `"[object Object]"`) and ignore own methods.
+- [ ] ToPrimitive elsewhere: `Error.prototype.toString` on an object `message` and numeric built-in arguments outside
+      `Math` and `Date` (`at`, `indexOf` start, `toFixed` digits) still use the built-in form (`NaN`,
+      `"[object Object]"`) and ignore own methods.
 - [x] Property keys follow ToPropertyKey: `x[null]`, `x[true]`, and objects (via their built-in string form) become
      string keys.

@@ -460,15 +461,15 @@ reject }` object.
 - [x] `getTimezoneOffset`, arithmetic, relational comparison, and `instanceof Date`.
 - [x] Date values serialize to ISO strings; invalid dates serialize to `null`.
 - [x] Local and UTC Date setters, including native argument coercion, mutation, rollover, invalid-Date recovery, and
-      `TimeClip` behavior.
+      `TimeClip` behavior. On an invalid Date every setter but `setTime` and `set(UTC)FullYear` answers `NaN` without
+      writing, so a time set inside an argument's `valueOf` survives.
 - [x] `Date.prototype.toUTCString` and its `toGMTString` alias.
 - [x] `toDateString` and `toTimeString` in the host's local timezone.
 - [x] `toLocaleString`, `toLocaleDateString`, and `toLocaleTimeString` always format as `en-US` in UTC
      (`"1/1/1970, 12:00:00 AM"`) so output does not depend on the host.
 - [x] Native one-argument Date coercion for supported values, including booleans, null, arrays, and plain objects.
- [x] Date setters and one-argument construction coerce object arguments through their own `valueOf`/`toString` and
-      surface their throws.
- [ ] Multi-argument construction and `Date.UTC` coerce object arguments the same way (see ToPrimitive above).
+- [x] Date setters, construction, and `Date.UTC` coerce object arguments through their own `valueOf`/`toString` in
+      argument order and surface their throws; only the first seven components are converted.
 - [x] Native Date loose-equality and default primitive-coercion semantics, using CodeMode's deterministic ISO string
      representation for the string primitive.
 - [x] Native `RangeError` branding for invalid `toISOString()` calls.
@@ -1136,18 +1136,15 @@ class Frame<R> {
      }

      if (pattern.type === "ObjectPattern") {
-        if (!(value instanceof Obj)) {
-          throw typeError(
-            `Object destructuring requires a data object or array value, received ${describeValue(value)}.`,
-            pattern,
-          )
+        if (value === null || value === undefined) {
+          throw typeError(`Cannot destructure ${describeValue(value)} as it is ${value}.`, pattern)
        }

        const consumed = new Set<PropertyKey>()
        for (const property of pattern.properties) {
          if (property.type === "RestElement") {
            const rest = new Obj(self.ctx.builtins.Object)
-            assign(rest, value, consumed)
+            assign(rest, enumerableSource(self.ctx, "Object destructuring", value, pattern), consumed)
            yield* self.declarePattern(property.argument, rest, mutable, property, initialize)
            continue
          }
@@ -1156,7 +1153,7 @@ class Frame<R> {
          consumed.add(typeof key === "symbol" ? key : String(key))
          yield* self.declarePattern(
            property.value,
-            self.readProperty(value, key, property),
+            self.destructuredProperty(value, key, property),
            mutable,
            property,
            initialize,
@@ -1195,24 +1192,21 @@ class Frame<R> {
      }

      if (pattern.type === "ObjectPattern") {
-        if (!(value instanceof Obj)) {
-          throw invalidData(
-            `Object destructuring requires a data object or array value, received ${describeValue(value)}.`,
-            pattern,
-          )
+        if (value === null || value === undefined) {
+          throw typeError(`Cannot destructure ${describeValue(value)} as it is ${value}.`, pattern)
        }

        const consumed = new Set<PropertyKey>()
        for (const property of pattern.properties) {
          if (property.type === "RestElement") {
            const rest = new Obj(self.ctx.builtins.Object)
-            assign(rest, value, consumed)
+            assign(rest, enumerableSource(self.ctx, "Object destructuring", value, pattern), consumed)
            yield* self.assignPattern(property.argument, rest, property)
            continue
          }
          const key = yield* self.destructuringPropertyKey(property)
          consumed.add(typeof key === "symbol" ? key : String(key))
-          yield* self.assignPattern(property.value, self.readProperty(value, key, property), property)
+          yield* self.assignPattern(property.value, self.destructuredProperty(value, key, property), property)
        }
        return
      }
@@ -2189,32 +2183,48 @@ class Frame<R> {
        : propertyNode.type === "Identifier"
          ? propertyNode.name
          : self.toPropertyKey(yield* self.evaluateExpression(propertyNode))
-
-      if (objectValue instanceof ToolReference) {
-        if (typeof key !== "string") {
-          throw typeError("Tool paths must use string property names.", propertyNode)
-        }
-        return new ToolReference([...objectValue.path, key])
-      }
-
-      if (objectValue instanceof Obj) return { target: objectValue, key, receiver: objectValue }
-
-      // Strings own length and indexes; every other primitive property reads through the wrapper prototype.
-      if (typeof objectValue === "string") {
-        if (key === "length") return { value: objectValue.length }
-        const index = typeof key === "symbol" ? undefined : parseArrayIndex(key)
-        if (index !== undefined) return { value: objectValue[index] }
-      }
-      const proto = primitivePrototype(self.ctx.builtins, objectValue)
-      if (proto !== undefined) return { target: proto, key, receiver: objectValue }
-
-      if (objectValue === null || objectValue === undefined) {
-        throw typeError(`Cannot read properties of ${objectValue} (reading '${String(key)}').`, objectNode)
-      }
-      throw typeError("Cannot access a property on a non-object value.", objectNode)
+      return self.resolveProperty(objectValue, key, objectNode, propertyNode)
    })
  }

+  private resolveProperty(
+    objectValue: Value,
+    key: PropertyKey,
+    objectNode: AstNode,
+    propertyNode: AstNode,
+  ): MemberReference | ToolReference | { value: Value } {
+    if (objectValue instanceof ToolReference) {
+      if (typeof key !== "string") {
+        throw typeError("Tool paths must use string property names.", propertyNode)
+      }
+      return new ToolReference([...objectValue.path, key])
+    }
+
+    if (objectValue instanceof Obj) return { target: objectValue, key, receiver: objectValue }
+
+    // Strings own length and indexes; every other primitive property reads through the wrapper prototype.
+    if (typeof objectValue === "string") {
+      if (key === "length") return { value: objectValue.length }
+      const index = typeof key === "symbol" ? undefined : parseArrayIndex(key)
+      if (index !== undefined) return { value: objectValue[index] }
+    }
+    const proto = primitivePrototype(this.ctx.builtins, objectValue)
+    if (proto !== undefined) return { target: proto, key, receiver: objectValue }
+
+    if (objectValue === null || objectValue === undefined) {
+      throw typeError(`Cannot read properties of ${objectValue} (reading '${String(key)}').`, objectNode)
+    }
+    throw typeError("Cannot access a property on a non-object value.", objectNode)
+  }
+
+  // One destructured property, read the way a member expression would read it (primitives use their prototype).
+  private destructuredProperty(source: Value, key: PropertyKey, node: AstNode): Value {
+    const reference = this.resolveProperty(source, key, node, node)
+    if (reference instanceof ToolReference) return reference
+    if ("value" in reference) return reference.value
+    return this.readProperty(reference.target, reference.key, node, reference.receiver)
+  }
+
  private readReference(reference: MemberReference, node: MemberExpression): Value {
    // Reject unknown promise properties so a missing await cannot hide.
    if (reference.target instanceof PromiseObj && !has(reference.target, reference.key)) {
@@ -16,8 +16,11 @@ const constructDate = <R>(ctx: Interpreter<R>, args: Array<Value>, proto: Obj) =
        : new DateObj(proto, new Date(coerceToNumber(value)).getTime()),
    )
  }
-  const parts = args.map((arg) => coerceToNumber(arg))
-  return Effect.succeed(new DateObj(proto, new Date(...(parts as [number, number])).getTime()))
+  // The spec converts at most seven components, in order, so extra arguments never run program code.
+  return Effect.map(
+    Effect.forEach(args.slice(0, 7), (arg) => toPrimitiveNumber(ctx, arg), { concurrency: 1 }),
+    (parts) => new DateObj(proto, new Date(...(parts as [number, number])).getTime()),
+  )
 }

 type Getter = keyof {
@@ -79,7 +82,15 @@ export const dateGlobal = <R>(ctx: Interpreter<R>) => {
  methods(builtins, date, [
    ["now", 0, () => Date.now()],
    ["parse", 1, (_, args) => Date.parse(coerceToString(args[0]))],
-    ["UTC", 7, (_, args) => Date.UTC(...(args.map((arg) => coerceToNumber(arg)) as Parameters<typeof Date.UTC>))],
+    [
+      "UTC",
+      7,
+      (_, args) =>
+        Effect.map(
+          Effect.forEach(args.slice(0, 7), (arg) => toPrimitiveNumber(ctx, arg), { concurrency: 1 }),
+          (parts) => Date.UTC(...(parts as Parameters<typeof Date.UTC>)),
+        ),
+    ],
  ])

  const self = (thisValue: Value, name: string) => receiver(DateObj, thisValue, `Date.prototype.${name}`)
@@ -125,6 +136,8 @@ export const dateGlobal = <R>(ctx: Interpreter<R>) => {
              concurrency: 1,
            }),
            (values) => {
+              // Every setter but setTime and setFullYear leaves an invalid Date untouched and answers NaN.
+              if (Number.isNaN(hosted.getTime()) && name !== "setTime" && !name.endsWith("FullYear")) return NaN
              target.time = hosted[name](...(values as [number, number, number, number]))
              return target.time
            },
@@ -1688,3 +1688,52 @@ describe("ToPrimitive: operators and conversions honor program valueOf and toStr
    expect(failure.message).toContain("Cannot convert object to primitive value")
  })
 })
+
+describe("object destructuring from primitives", () => {
+  test("reads through the primitive's prototype like member access", async () => {
+    expect(
+      await value(`
+        const { length, 0: first, toUpperCase } = "abc"
+        const { toFixed } = 1.5
+        const {} = true
+        const { 0: a, ...rest } = "xyz"
+        const { ...none } = 42
+        let n
+        ;({ length: n } = "hello")
+        return [length, first, toUpperCase.call("q"), toFixed.call(2.345, 1), a, rest, none, n]
+      `),
+    ).toEqual([3, "a", "Q", "2.3", "x", { 1: "y", 2: "z" }, {}, 5])
+  })
+
+  test("only null and undefined sources throw", async () => {
+    expect((await error(`const { a } = null`)).message).toContain("Cannot destructure null as it is null")
+    expect((await error(`const {} = undefined`)).message).toContain("Cannot destructure undefined")
+    expect((await error(`let a; ({ a } = undefined)`)).message).toContain("Cannot destructure undefined")
+  })
+})
+
+describe("Date components convert through ToPrimitive", () => {
+  test("construction and Date.UTC ask each of the first seven arguments in order", async () => {
+    expect(
+      await value(`
+        const seen = []
+        const part = (n) => ({ valueOf() { seen.push(n); return n } })
+        const time = new Date(part(2024), part(1), part(2), part(3), part(4), part(5), part(6), part(99)).getTime()
+        const utc = Date.UTC(2024, { valueOf() { return 0 } }, 15)
+        return [seen, time === new Date(2024, 1, 2, 3, 4, 5, 6).getTime(), utc === Date.UTC(2024, 0, 15)]
+      `),
+    ).toEqual([[2024, 1, 2, 3, 4, 5, 6], true, true])
+    expect((await error(`new Date(2024, { valueOf() { throw new RangeError("boom") } })`)).message).toContain("boom")
+  })
+
+  test("setters on an invalid Date answer NaN without overwriting a time set during coercion", async () => {
+    expect(
+      await value(`
+        const d = new Date(NaN)
+        const result = d.setDate({ valueOf() { d.setTime(0); return 1 } })
+        const y = new Date(NaN)
+        return [Number.isNaN(result), d.getTime(), y.setFullYear(2020) === Date.UTC(2020, 0, 1) - y.getTimezoneOffset() * 60000]
+      `),
+    ).toEqual([true, 0, true])
+  })
+})
@@ -2,6 +2,7 @@
  "revision": "250f204f23a9249ff204be2baec29600faae7b75",
  "directories": [
    "built-ins/Array/prototype",
+    "built-ins/Date",
    "built-ins/Function/prototype/apply",
    "built-ins/Function/prototype/bind",
    "built-ins/Function/prototype/call",
@@ -17,6 +18,7 @@
    "built-ins/parseFloat",
    "built-ins/parseInt",
    "language/arguments-object",
+    "language/expressions/assignment",
    "language/expressions/does-not-equals",
    "language/expressions/equals",
    "language/expressions/exponentiation",
@@ -925,16 +925,6 @@ language/statements/async-generator/dstr/dflt-ary-ptrn-elem-id-iter-val-array-pr
 language/statements/async-generator/return-undefined-implicit-and-explicit.js  # Actual ["tick 1", "tick 2", "g1 ret", "g2 ret", "g3 ret", "g4 ret"] and expected ["tick 1", "g1 ret"
 language/statements/const/dstr/ary-init-iter-get-err-array-prototype.js  # Expected a TypeError to be thrown but no exception was thrown at all
 language/statements/const/dstr/ary-ptrn-elem-id-iter-val-array-prototype.js  # Expected SameValue(«3», «42») to be true
-language/statements/for-await-of/async-func-decl-dstr-obj-empty-bool.js  # TypeError: Object destructuring requires a data object or array value, received a boolean.
-language/statements/for-await-of/async-func-decl-dstr-obj-empty-num.js  # TypeError: Object destructuring requires a data object or array value, received a number.
-language/statements/for-await-of/async-func-decl-dstr-obj-empty-string.js  # TypeError: Object destructuring requires a data object or array value, received a string.
-language/statements/for-await-of/async-func-decl-dstr-obj-rest-number.js  # TypeError: Object destructuring requires a data object or array value, received a number.
-language/statements/for-await-of/async-func-decl-dstr-obj-rest-str-val.js  # TypeError: Object destructuring requires a data object or array value, received a string.
-language/statements/for-await-of/async-gen-decl-dstr-obj-empty-bool.js  # TypeError: Object destructuring requires a data object or array value, received a boolean.
-language/statements/for-await-of/async-gen-decl-dstr-obj-empty-num.js  # TypeError: Object destructuring requires a data object or array value, received a number.
-language/statements/for-await-of/async-gen-decl-dstr-obj-empty-string.js  # TypeError: Object destructuring requires a data object or array value, received a string.
-language/statements/for-await-of/async-gen-decl-dstr-obj-rest-number.js  # TypeError: Object destructuring requires a data object or array value, received a number.
-language/statements/for-await-of/async-gen-decl-dstr-obj-rest-str-val.js  # TypeError: Object destructuring requires a data object or array value, received a string.
 language/statements/for-in/S12.6.4_A7_T2.js  # for...in visits keys deleted during the loop
 language/statements/for-in/order-enumerable-shadowed.js  # Object.create property descriptors are not supported; assign the fields after creating the object.
 language/statements/for-in/S12.6.4_A6.1.js  # TypeError: FACTORY cannot be constructed: user-defined constructors and classes are not supported. C
@@ -959,11 +949,6 @@ language/statements/for-of/dstr/const-ary-init-iter-get-err-array-prototype.js
 language/statements/for-of/dstr/const-ary-ptrn-elem-id-iter-val-array-prototype.js  # Expected SameValue(«3», «42») to be true
 language/statements/for-of/dstr/let-ary-init-iter-get-err-array-prototype.js  # Expected a TypeError to be thrown but no exception was thrown at all
 language/statements/for-of/dstr/let-ary-ptrn-elem-id-iter-val-array-prototype.js  # Expected SameValue(«3», «42») to be true
-language/statements/for-of/dstr/obj-empty-bool.js  # Object destructuring requires a data object or array value, received a boolean.
-language/statements/for-of/dstr/obj-empty-num.js  # Object destructuring requires a data object or array value, received a number.
-language/statements/for-of/dstr/obj-empty-string.js  # Object destructuring requires a data object or array value, received a string.
-language/statements/for-of/dstr/obj-rest-number.js  # Object destructuring requires a data object or array value, received a number.
-language/statements/for-of/dstr/obj-rest-str-val.js  # Object destructuring requires a data object or array value, received a string.
 language/statements/for-of/dstr/var-ary-init-iter-get-err-array-prototype.js  # Expected a TypeError to be thrown but no exception was thrown at all
 language/statements/for-of/dstr/var-ary-ptrn-elem-id-iter-val-array-prototype.js  # Expected SameValue(«3», «42») to be true
 language/statements/for-of/throw-from-catch.js  # … cannot be constructed: user-defined constructors and classes are not supported. Call it as a funct
@@ -1097,3 +1082,35 @@ built-ins/Array/prototype/some/15.4.4.17-7-c-i-26.js  # TypeError: Array.prototy
 built-ins/Array/prototype/some/15.4.4.17-7-c-i-27.js  # TypeError: Array.prototype.some called on incompatible receiver an Arguments.
 built-ins/parseFloat/S15.1.2.3_A7.5.js  # TypeError: Cannot read properties of undefined (reading '…').
 built-ins/parseInt/S15.1.2.2_A9.5.js  # TypeError: Cannot read properties of undefined (reading '…').
+built-ins/Date/S15.9.3.1_A4_T0.js  # `new Date(new PoisonedValueOf(1))` throws a Test262Error exception Expected a Test262Error but got a
+built-ins/Date/S15.9.3.1_A4_T1.js  # `new Date(new PoisonedValueOf(1), new PoisonedValueOf(2))` throws a Test262Error exception Expected 
+built-ins/Date/S15.9.3.1_A4_T2.js  # `new Date(new PoisonedValueOf(1), new PoisonedValueOf(2), new PoisonedValueOf(3))` throws a Test262E
+built-ins/Date/S15.9.3.1_A4_T3.js  # `new Date(new PoisonedValueOf(1), new PoisonedValueOf(2), new PoisonedValueOf(3), new PoisonedValueO
+built-ins/Date/S15.9.3.1_A4_T4.js  # `new Date(new PoisonedValueOf(1), new PoisonedValueOf(2), new PoisonedValueOf(3), new PoisonedValueO
+built-ins/Date/S15.9.3.1_A4_T5.js  # `new Date(new PoisonedValueOf(1), new PoisonedValueOf(2), new PoisonedValueOf(3), new PoisonedValueO
+built-ins/Date/S15.9.3.1_A4_T6.js  # `new Date(new PoisonedValueOf(1), new PoisonedValueOf(2), new PoisonedValueOf(3), new PoisonedValueO
+built-ins/Date/prototype/toJSON/invoke-result.js  # TypeError: Date.prototype.toJSON called on incompatible receiver a data object.
+built-ins/Date/prototype/toJSON/to-primitive-value-of.js  # TypeError: Date.prototype.toJSON called on incompatible receiver a data object.
+built-ins/Date/prototype/toString/format.js  # Expected SameValue(«null», «null») to be false
+built-ins/Date/prototype/toString/negative-year.js  # Date.prototype.toString serializes year -1 to "-0001" Expected SameValue(«undefined», «"-0001"») to 
+language/expressions/assignment/dstr/array-elem-iter-rtrn-close-err.js  # TypeError: Iterator next must be a function.
+language/expressions/assignment/dstr/array-elem-iter-thrw-close-err.js  # Expected SameValue(«1», «0») to be true
+language/expressions/assignment/dstr/array-elem-iter-thrw-close.js  # Expected SameValue(«1», «0») to be true
+language/expressions/assignment/dstr/array-elem-trlg-iter-list-thrw-close-err.js  # Expected SameValue(«1», «0») to be true
+language/expressions/assignment/dstr/array-elem-trlg-iter-list-thrw-close.js  # Expected SameValue(«1», «0») to be true
+language/expressions/assignment/dstr/array-elem-trlg-iter-rest-rtrn-close-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/expressions/assignment/dstr/array-elem-trlg-iter-rest-rtrn-close-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/expressions/assignment/dstr/array-elem-trlg-iter-rest-rtrn-close.js  # Expected SameValue(«11», «1») to be true
+language/expressions/assignment/dstr/array-elem-trlg-iter-rest-thrw-close-err.js  # Expected SameValue(«11», «1») to be true
+language/expressions/assignment/dstr/array-elem-trlg-iter-rest-thrw-close.js  # Expected SameValue(«11», «1») to be true
+language/expressions/assignment/dstr/array-rest-iter-rtrn-close-err.js  # TypeError: Iterator next must be a function.
+language/expressions/assignment/dstr/array-rest-iter-rtrn-close-null.js  # TypeError: Iterator next must be a function.
+language/expressions/assignment/dstr/array-rest-iter-rtrn-close.js  # Test262Error
+language/expressions/assignment/dstr/array-rest-iter-thrw-close-err.js  # Expected SameValue(«11», «0») to be true
+language/expressions/assignment/dstr/array-rest-iter-thrw-close.js  # Expected SameValue(«11», «0») to be true
+language/expressions/assignment/dstr/array-rest-lref-err.js  # Expected SameValue(«1», «0») to be true
+language/expressions/assignment/target-member-computed-reference-null.js  # Expected a DummyError but got a TypeError
+language/expressions/assignment/target-member-computed-reference-undefined.js  # Expected a DummyError but got a TypeError
+language/expressions/assignment/target-member-computed-reference.js  # Expected a DummyError but got a TypeError
+language/expressions/assignment/target-member-identifier-reference-null.js  # Expected SameValue(«0», «1») to be true
+language/expressions/assignment/target-member-identifier-reference-undefined.js  # Expected SameValue(«0», «1») to be true