Object::get_own_properties() is a bit unwieldy to use - especially as
StringOnly is about to no longer be the default value. The spec has an
abstract operation specifically for this (EnumerateObjectProperties),
so let's use that. No functionality change.
Specifically:
- Object::get_own_properties()
- Object::put_own_property()
- Object::put_own_property_by_index()
These APIs make no sense (and are inconsistent, get_own_property()
didn't have this parameter, for example) - and as expected we were
always passing in the same object we were calling the method on anyway.
Not sure if this regressed at some point or just never worked, it
definitely wasn't tested at all. We would always return undefined when
returning from a try statement block, handler, or finalizer.
We should be able to get the 'typeof' string for any value directly, so
this is now a standalone Value::typeof() method instead of being part of
UnaryExpression::execute().
The auto naming of function expressions is a purely syntactic
decision, so shouldn't be decided based on the dynamic type of
an assignment. This moves the decision making into the parser.
One icky hack is that we add a field to FunctionExpression to
indicate whether we can autoname. The real solution is to actually
generate a CompoundExpression node so that the parser can make
the correct decision, however this would have a potentially
significant run time cost.
This does not correct the behaviour for class expressions.
Patch from Anonymous.
We now store 32-bit integers as 32-bit integers directly which avoids
having to convert them from doubles when they're only used as 32-bit
integers anyway. :^)
This patch feels a bit incomplete and there's a lot of opportunities
to take advantage of this information. We'll have to find and exploit
them eventually.
Previously we would generate function names for anonymous functions
on every AssignmentExpression, even if we weren't assigning a function.
We were also setting names of anonymous functions in arrays, which is
apparently a SpiderMonkey specific behavior not supported by V8, JSC
or required by ECMA262. This patch removes that behavior.
This is a huge performance improvement on the CanvasCycle demo! :^)
For various statements the spec states:
Return NormalCompletion(empty).
In those cases we have been returning undefined so far, which is
incorrect.
In other cases it states:
Return Completion(UpdateEmpty(stmtCompletion, undefined)).
Which essentially means a statement is evaluated and its completion
value returned if non-empty, and undefined otherwise.
While not actually noticeable in normal scripts as the VM's "last value"
can't be accessed from JS code directly (with the exception of eval(),
see below), it provided an inconsistent experience in the REPL:
> if (true) 42;
42
> if (true) { 42; }
undefined
This also fixes the case where eval() would return undefined if the last
executed statement is not a value-producing one:
eval("1;;;;;")
eval("1;{}")
eval("1;var a;")
As a consequence of the changes outlined above, these now all correctly
return 1.
See https://tc39.es/ecma262/#sec-block-runtime-semantics-evaluation,
"NOTE 2".
Fixes#3609.
(...and ASSERT_NOT_REACHED => VERIFY_NOT_REACHED)
Since all of these checks are done in release builds as well,
let's rename them to VERIFY to prevent confusion, as everyone is
used to assertions being compiled out in release.
We can introduce a new ASSERT macro that is specifically for debug
checks, but I'm doing this wholesale conversion first since we've
accumulated thousands of these already, and it's not immediately
obvious which ones are suitable for ASSERT.
If it's missing we get an empty value, but we can't use that with
to_string_without_side_effects() so we have to use undefined as the
default.
Fixes#5142.
If we have a function as class extends value, we still cannot assume
that it has a prototype property and that property has a function or
null as its value - blindly calling to_object() on it may fail.
Fixes#5075.
Without this, the oss-fuzz build says:
../Userland/Libraries/LibJS/AST.cpp:58:34: error: member access into incomplete type 'const std::type_info'
return demangle(typeid(*this).name()).substring(4);
^
