[immutable-arraybuffer] ArrayBuffer.prototype.immutable

Author: gibson042

test/built-ins/ArrayBuffer/prototype/immutable/prop-desc.js

@@ -0,0 +1,40 @@
+// Copyright (C) 2025 Richard Gibson. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-get-arraybuffer.prototype.immutable
+description: Checks the "immutable" property of ArrayBuffer.prototype.
+info: |
+  ArrayBuffer.prototype.immutable is an accessor property whose set accessor
+  function is undefined.
+
+  ECMAScript Standard Built-in Objects
+  ...
+  For functions that are specified as properties of objects, the name value is
+  the property name string used to access the function. Functions that are
+  specified as get or set accessor functions of built-in properties have "get"
+  or "set" (respectively) passed to the prefix parameter when calling
+  CreateBuiltinFunction.
+  ...
+  Every accessor property described in clauses 19 through 28 and in Annex B.2
+  has the attributes { [[Enumerable]]: false, [[Configurable]]: true } unless
+  otherwise specified. If only a get accessor function is described, the set
+  accessor function is the default value, undefined.
+features: [immutable-arraybuffer]
+includes: [propertyHelper.js]
+---*/
+
+var desc = Object.getOwnPropertyDescriptor(ArrayBuffer.prototype, "immutable");
+var isHardened = Object.isFrozen(Object);
+if (isHardened && desc.get) {
+  Object.defineProperty(desc, "get", { configurable: false });
+}
+
+assert.sameValue(desc.value, undefined);
+assert.sameValue(desc.set, undefined);
+verifyCallableProperty(desc, "get", "get immutable", 0, { configurable: !isHardened });
+
+verifyPrimordialProperty(ArrayBuffer.prototype, "immutable", {
+  enumerable: false,
+  configurable: true
+});

test/built-ins/ArrayBuffer/prototype/immutable/return-immutable.js

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+// Copyright (C) 2025 Richard Gibson. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-get-arraybuffer.prototype.immutable
+description: Return value according to the [[ArrayBufferIsImmutable]] internal slot.
+info: |
+  get ArrayBuffer.prototype.immutable
+  1. Let O be the this value.
+  2. Perform ? RequireInternalSlot(O, [[ArrayBufferData]]).
+  3. If IsSharedArrayBuffer(O) is true, throw a TypeError exception.
+  4. Return IsImmutableBuffer(O).
+
+  IsImmutableBuffer ( arrayBuffer )
+  1. If arrayBuffer has an [[ArrayBufferIsImmutable]] internal slot, return true.
+  2. Return false.
+features: [ArrayBuffer, immutable-arraybuffer]
+includes: [detachArrayBuffer.js]
+---*/
+
+var ab = new ArrayBuffer(1);
+assert.sameValue(ab.immutable, false);
+
+var iab = ab.transferToImmutable();
+assert.sameValue(iab.immutable, true);
+
+$DETACHBUFFER(ab);
+assert.sameValue(ab.immutable, false);

test/built-ins/ArrayBuffer/prototype/immutable/this-has-no-arraybufferdata-internal.js

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+// Copyright (C) 2025 Richard Gibson. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-get-arraybuffer.prototype.immutable
+description: >
+  Throws a TypeError exception when `this` does not have a [[ArrayBufferData]]
+  internal slot
+info: |
+  get ArrayBuffer.prototype.immutable
+  1. Let O be the this value.
+  2. Perform ? RequireInternalSlot(O, [[ArrayBufferData]]).
+features: [DataView, Int8Array, ArrayBuffer, immutable-arraybuffer]
+---*/
+
+var getter = Object.getOwnPropertyDescriptor(
+  ArrayBuffer.prototype, "immutable"
+).get;
+
+assert.sameValue(typeof getter, "function", "Getter must exist.");
+
+var badReceivers = [
+  ["plain object", {}],
+  ["array", []],
+  ["function", function(){}],
+  ["ArrayBuffer.prototype", ArrayBuffer.prototype],
+  ["TypedArray", new Int8Array(8)],
+  ["DataView", new DataView(new ArrayBuffer(8), 0)]
+];
+
+for (var i = 0; i < badReceivers.length; i++) {
+  var label = badReceivers[i][0];
+  var value = badReceivers[i][1];
+  assert.throws(TypeError, function() {
+    getter.call(value);
+  }, label);
+}
+
+assert.throws(TypeError, function() {
+  ArrayBuffer.prototype.immutable;
+}, "invoked as prototype property access");
+
+assert.throws(TypeError, function() {
+  getter();
+}, "invoked as function");

test/built-ins/ArrayBuffer/prototype/immutable/this-is-not-object.js

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+// Copyright (C) 2025 Richard Gibson. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-get-arraybuffer.prototype.immutable
+description: Throws a TypeError exception when `this` is not an object
+info: |
+  get ArrayBuffer.prototype.immutable
+  1. Let O be the this value.
+  2. Perform ? RequireInternalSlot(O, [[ArrayBufferData]]).
+features: [ArrayBuffer, immutable-arraybuffer]
+---*/
+
+var getter = Object.getOwnPropertyDescriptor(
+  ArrayBuffer.prototype, "immutable"
+).get;
+
+assert.sameValue(typeof getter, "function", "Getter must exist.");
+
+var badReceivers = [
+  ["undefined", undefined],
+  ["null", null],
+  ["number", 42],
+  ["string", "1"],
+  ["true", true],
+  ["false", false],
+  typeof Symbol === "undefined" ? undefined : ["unique symbol", Symbol("s")],
+  typeof Symbol === "undefined" || !Symbol.for ? undefined : ["registered symbol", Symbol.for("s")],
+  typeof BigInt === "undefined" ? undefined : ["bigint", BigInt(1)]
+];
+
+for (var i = 0; i < badReceivers.length; i++) {
+  if (!badReceivers[i]) continue;
+  var label = badReceivers[i][0];
+  var value = badReceivers[i][1];
+  assert.throws(TypeError, function() {
+    getter.call(value);
+  }, label);
+}

test/built-ins/ArrayBuffer/prototype/immutable/this-is-sharedarraybuffer.js

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+// Copyright (C) 2025 Richard Gibson. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-get-arraybuffer.prototype.immutable
+description: Throws a TypeError exception when `this` is a SharedArrayBuffer
+info: |
+  get ArrayBuffer.prototype.immutable
+  1. Let O be the this value.
+  2. Perform ? RequireInternalSlot(O, [[ArrayBufferData]]).
+  3. If IsSharedArrayBuffer(O) is true, throw a TypeError exception.
+features: [SharedArrayBuffer, ArrayBuffer, immutable-arraybuffer]
+---*/
+
+var getter = Object.getOwnPropertyDescriptor(
+  ArrayBuffer.prototype, "immutable"
+).get;
+
+assert.sameValue(typeof getter, "function", "Getter must exist.");
+
+var sab = new SharedArrayBuffer(4);
+assert.throws(TypeError, function() {
+  getter.call(sab);
+});