extensible-nursery-chars.js

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gczeal(0);

function assertStringFlag(s, flag) {

    if (typeof stringRepresentation === "function") {

        var rep = JSON.parse(stringRepresentation(s));

        assertEq(rep.flags.includes(flag), true, "Missing flag: " + flag);

function test(extensibleTenured, ropeTenured) {

    var s1 = "12345678901234567890";

    // Create an extensible string with chars in the nursery.

    var s2 = ensureLinearString(newRope(newRope(newRope(s1, s1), s1), s1));

    if (extensibleTenured) {

        minorgc();

        minorgc();

    assertEq(isNurseryAllocated(s2), !extensibleTenured);

    assertStringFlag(s2, "EXTENSIBLE");

    // Try to reuse its buffer.

    var s3 = ensureLinearString(newRope(s2, s1, {nursery: !ropeTenured}));

    assertEq(isNurseryAllocated(s3), !ropeTenured);

    assertStringFlag(s3, "EXTENSIBLE");

    // If the rope was tenured and the extensible string had nursery-allocated

    // chars, we don't reuse its buffer so both strings will be extensible.

    // In all other cases, s2 is now a dependent string.

    if (ropeTenured && !extensibleTenured) {

        assertStringFlag(s2, "EXTENSIBLE");

    } else {

        assertStringFlag(s2, "DEPENDENT_BIT");

    assertEq(s2, "12345678901234567890123456789012345678901234567890123456789012345678901234567890");

    assertEq(s3, "1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890");

test(false, false);

test(false, true);

test(true, false);

test(true, true);