fb89c324c5
This renames Object::to_primitive() to Object::ordinary_to_primitive()
for two reasons:
- No confusion with Value::to_primitive()
- To match the spec's name
Also change existing uses of Object::to_primitive() to
Value::to_primitive() when the spec uses the latter (which will still
call Object::ordinary_to_primitive()). Object::to_string() has been
removed as it's not needed anymore (and nothing the spec uses).
This makes it possible to overwrite an object's toString and valueOf and
have them provide results for anything that uses to_primitive() - e.g.:
const o = { toString: undefined, valueOf: () => 42 };
Number(o) // 42, previously NaN
["foo", o].toString(); // "foo,42", previously "foo,[object Object]"
++o // 43, previously NaN
etc.
23 lines
740 B
JavaScript
23 lines
740 B
JavaScript
test("object with custom toString", () => {
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const o = { toString: () => "foo" };
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expect(o + "bar").toBe("foobar");
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expect([o, "bar"].toString()).toBe("foo,bar");
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});
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test("object with uncallable toString and custom valueOf", () => {
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const o = { toString: undefined, valueOf: () => "foo" };
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expect(o + "bar").toBe("foobar");
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expect([o, "bar"].toString()).toBe("foo,bar");
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});
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test("object with custom valueOf", () => {
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const o = { valueOf: () => 42 };
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expect(Number(o)).toBe(42);
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expect(o + 1).toBe(43);
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});
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test("object with uncallable valueOf and custom toString", () => {
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const o = { valueOf: undefined, toString: () => "42" };
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expect(Number(o)).toBe(42);
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expect(o + 1).toBe("421");
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});
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