LayoutTests/js/script-tests/string-repeat.js

description("This test checks the ES6 string functions repeat().");

shouldBe("'foo bar'.repeat(+0)", "''");
shouldBe("'foo bar'.repeat(-0)", "''");
shouldBe("'foo bar'.repeat(1)", "'foo bar'");
shouldBe("'foo bar'.repeat(2)", "'foo barfoo bar'");
shouldBe("'フーバー'.repeat(0)", "''");
shouldBe("'フーバー'.repeat(1)", "'フーバー'");
shouldBe("'フーバー'.repeat(2)", "'フーバーフーバー'");
shouldBe("'foo barfoo bar'.repeat(2)", "'foo barfoo barfoo barfoo bar'");
shouldBe("'foo barfoo bar'.repeat(2.2)", "'foo barfoo barfoo barfoo bar'");
shouldBe("'foo barfoo bar'.repeat(2.8)", "'foo barfoo barfoo barfoo bar'");
shouldBe("'foo'.repeat(3.1)", "'foofoofoo'");
shouldBe("'foo'.repeat('2')", "'foofoo'");
shouldBe("'foo'.repeat(NaN)", "''");
shouldBe("'foo'.repeat(null)", "''");
shouldBe("'foo'.repeat(true)", "'foo'");
shouldBe("'foo'.repeat(false)", "''");
shouldBe("'foo'.repeat(undefined)", "''");
shouldBe("'foo'.repeat()", "''");
shouldBe("'f'.repeat(0)", "''");
shouldBe("'f'.repeat(1)", "'f'");
shouldBe("'f'.repeat(10)", "'ffffffffff'");
shouldBe("'フ'.repeat(0)", "''");
shouldBe("'フ'.repeat(1)", "'フ'");
shouldBe("'フ'.repeat(2)", "'フフ'");

// Repeat empty strings.
shouldBe("''.repeat(1000)", "''");
shouldBe("''.repeat(0xFFFFFFFF)", "''");
shouldBe("''.repeat(0xFFFFFFFF + 1)", "''");

// Check range errors.
shouldThrow("'foo bar'.repeat(-1)", "'RangeError: String.prototype.repeat argument must be greater than or equal to 0 and not be infinity'");
shouldThrow("'foo bar'.repeat(Infinity)", "'RangeError: String.prototype.repeat argument must be greater than or equal to 0 and not be infinity'");
shouldThrow("'foo bar'.repeat(-Infinity)", "'RangeError: String.prototype.repeat argument must be greater than or equal to 0 and not be infinity'");

// Check out of memory errors.
shouldThrow("'f'.repeat(0xFFFFFFFF)", "'Error: Out of memory'");
shouldThrow("'f'.repeat(0xFFFFFFFF + 1)", "'Error: Out of memory'");
shouldThrow("'foo'.repeat(0xFFFFFFFFF)", "'Error: Out of memory'");
shouldThrow("'foo'.repeat(0xFFFFFFFFF + 1)", "'Error: Out of memory'");
shouldThrow("'foo bar'.repeat(0xFFFFFFFF)", "'Error: Out of memory'");
shouldThrow("'foo bar'.repeat(0xFFFFFFFF + 1)", "'Error: Out of memory'");

// Check side effects in repeat.
var sideEffect = "";
var stringRepeated = new String("foo bar");
stringRepeated.toString = function() {
    sideEffect += "A";
    return this;
}
var count = new Number(2);
count.valueOf = function() {
    sideEffect += "B";
    return this;
}
// Calling stringRepeated.repeat implicitly calls stringRepeated.toString(),
// and count.valueOf(), in that respective order.
shouldBe("stringRepeated.repeat(count)", "'foo barfoo bar'");
shouldBe("sideEffect == 'AB'", "true");

// If stringRepeated throws an exception count.valueOf() is not called.
stringRepeated.toString = function() {
    throw "error";
}
sideEffect = "";
shouldThrow("stringRepeated.repeat(count)", "'error'");
shouldBe("sideEffect == ''", "true");

// If count throws an exception stringRepeated.toString() was called.
stringRepeated.toString = function() {
    sideEffect += "A";
    return this;
}
count.valueOf = function() {
    throw "error";
}
sideEffect = "";
shouldThrow("stringRepeated.repeat(count)", "'error'");
shouldBe("sideEffect == 'A'", "true");