This patch adds `Array.prototype.reduce()` method to LibJS Runtime.
The implementation is (to my best knowledge) comformant to ECMA262.
The test `Array.prototype-generic-functions.js` demonstrates that the
function can be applied to other objects besides `Array`.
Let's treat it as zero like the ECMAScript spec does in toInteger().
That way we can use to_i32() and don't have to care about weird input
input values where a number is expected, i.e.
"foo".charAt() === "f"
"foo".charAt("bar") === "f"
"foo".charAt(0) === "f"
This patch adds a GetterSetterPair object. Values can now store pointers
to objects of this type. These objects are created when using
Object.defineProperty and providing an accessor descriptor.
This saves us both a bit of time and accuracy, as Serenity's strtod()
still is a little bit off sometimes - and stringifying the result and
parsing it again just increases that offset.
As these parameter-less overloads don't change the value's type and
just assume Type::Number, naming them as_i32() and as_size_t() is more
appropriate.
This patch is unfortunately rather large and might make some things feel
bloated, but it is necessary to fix a few flaws in LibJS, primarily
blindly coercing values to numbers without exception checks - i.e.
interpreter.argument(0).to_i32(); // can fail!!!
Some examples where the interpreter would actually crash:
var o = { toString: () => { throw Error() } };
+o;
o - 1;
"foo".charAt(o);
"bar".repeat(o);
To fix this, we now have the following...
to_double(Interpreter&)
to_i32()
to_i32(Interpreter&)
to_size_t()
to_size_t(Interpreter&)
...and a whole lot of exception checking.
There's intentionally no to_double(), use as_double() directly instead.
This way we still can use these convenient utility functions but don't
need to check for exceptions if we are sure the value already is a
number.
Fixes#2267.
Passing a Heap& to it only to then call interpreter() on that is weird.
Let's just give it the Interpreter& directly, like some of the other
to_something() functions.
This commit adds the following classes: SymbolObject, SymbolConstructor,
SymbolPrototype, and Symbol. This commit does not introduce any
new functionality to the Object class, so they cannot be used as
property keys in objects.
There are now two API's on Value:
- Value::to_string(Interpreter&) -- may throw.
- Value::to_string_without_side_effects() -- will never throw.
These are some pretty big sweeping changes, so it's possible that I did
some part the wrong way. We'll work it out as we go. :^)
Fixes#2123.
Rather than printing them to stderr directly the parser now keeps a
Vector<Error>, which allows the "owner" of the parser to consume them
individually after parsing.
The Error struct has a message, line number, column number and a
to_string() helper function to format this information into a meaningful
error message.
The Function() constructor will now include an error message when
throwing a SyntaxError.
The ECMAScript spec defines multiple equality operations which are used
all over the spec; this patch introduces them. Of course, the two
primary equality operations are AbtractEquals ('==') and StrictEquals
('==='), which have been renamed to 'abstract_eq' and 'strict_eq' in
this patch.
In support of the two operations mentioned above, the following have
also been added: SameValue, SameValueZero, and SameValueNonNumeric.
These are important to have, because they are used elsewhere in the spec
aside from the two primary equality comparisons.
"[Function.length is] the number of formal parameters. This number
excludes the rest parameter and only includes parameters before
the first one with a default value." - MDN
Console methods are now Value(void) functions.
JavaScript functions in the JavaScript ConsoleObject are now implemented
as simple wrappers around Console methods.
This will make it possible for LibJS users to easily override the
default behaviour of JS console functions (even their return value!)
once we add a way to override Console behaviour.
