- Let undefined variables throw a ReferenceError by using
Identifier::execute() rather than doing variable lookup manually and
ASSERT()ing
- Coerce value to number rather than ASSERT()ing
- Make code DRY
- Add tests
This allows us to run "run-tests -g" for testing with GC after every
heap allocation. This may flush out bugs that would otherwise not
occur if GC'ing only occasionally.
This "mutes" output from dbg() calls - which is not an issue inside
serenity itself but if the script is run on the host machine and stdout
and stderr are displayed in the same terminal window.
The addition of assert functions to Userland/js
was done before we had load(..) implemented. Now
that it exists, it seems like the right move the
test helper functions to pure javascript instead
of poluting js with random global functions.
"var" declarations are hoisted to the nearest function scope, while
"let" and "const" are hoisted to the nearest block scope.
This is done by the parser, which keeps two scope stacks, one stack
for the current var scope and one for the current let/const scope.
When the interpreter enters a scope, we walk all of the declarations
and insert them into the variable environment.
We don't support the temporal dead zone for let/const yet.
The MDN example for creating a custom error type in javascript uses:
function CustomError(foo, message, fileName, lineNumber) {
var instance = new Error(message, fileName, lineNumber);
instance.name = 'CustomError';
instance.foo = foo;
Object.setPrototypeOf(instance, Object.getPrototypeOf(this));
return instance;
}
The name property on the Error prototype needs to be settable for
this to work properly.
The output of FunctionPrototype::to_string is now more in line
with the output in Firefox. The builtin constructors have been
extended to include their function name in the output.