from_basics.js - mozsearch

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for (var constructor of anyTypedArrayConstructors) {

    // 'from' method is identical for all typed array constructors.

    assertEq(anyTypedArrayConstructors[0].from === constructor.from, true);

    // %TypedArray%.from copies arrays.

    var src = new constructor([1, 2, 3]), copy = constructor.from(src);

    assertEq(copy === src, false);

    assertEq(copy instanceof constructor, true);

    assertDeepEq(copy, src);

    // Non-element properties are not copied.

    var a = new constructor([0, 1]);

    a.name = "lisa";

    assertDeepEq(constructor.from(a), new constructor([0, 1]));

    // %TypedArray%.from can copy non-iterable objects, if they're array-like.

    src = {0: 0, 1: 1, length: 2};

    copy = constructor.from(src);

    assertEq(copy instanceof constructor, true);

    assertDeepEq(copy, new constructor([0, 1]));

    // Properties past the .length are not copied.

    src = {0: "0", 1: "1", 2: "two", 9: "nine", name: "lisa", length: 2};

    assertDeepEq(constructor.from(src), new constructor([0, 1]));

    // If an object has neither an @@iterator method nor .length,

    // then it's treated as zero-length.

    assertDeepEq(constructor.from({}), new constructor());

    // Primitives will be coerced to primitive wrapper first.

    assertDeepEq(constructor.from(1), new constructor());

    assertDeepEq(constructor.from("123"), new constructor([1, 2, 3]));

    assertDeepEq(constructor.from(true), new constructor());

    assertDeepEq(constructor.from(Symbol()), new constructor());

    // Source object property order doesn't matter.

    src = {length: 2, 1: "1", 0: "0"};

    assertDeepEq(constructor.from(src), new constructor([0, 1]));

if (typeof reportCompare === "function")

    reportCompare(true, true);