This ensures that js's error printing logic is used instead of the
generic value printing logic, which then lets eshost correctly parse
thrown SyntaxErrors using the normal LibJS exception format.
Using a Vector<Value> is unsafe as GC cannot see the stored values.
This is then vended to outside users of ConsoleClient, e.g. LibWeb and
WebContent, which is then outside of LibJS's control.
An example issue is if the client stores it for later use and forgets
to visit the stored values, meaning they can be destroyed at any time.
We can save the client from this by vending a MarkedVector<Value> to
them.
Instead of just printing 'ECMAScriptFunctionObject' (and leaking an
implementation detail in the process - this is not a public facing name)
let's instead print a different type string for each function kind, and
only keep the old class_name() printing for other JS::FunctionObject
subclasses.
When you try to run script containing only whitespace, it will return
undefined and doesn't do anything anyway. Let's match NodeJS behavior
and just don't display anything.
This only applies to REPL input and not to modules.
Constructing the HashMap in DeclarativeEnvironment was by far the most
expensive thing when making JavaScript function calls.
As it turns out, we don't really need this to be a HashMap in the first
place, as lookups are cached (by EnvironmentCoordinate) after the first
access, so after that we were not even looking in the HashMap, going
directly to the bindings Vector instead.
This reduces function_declaration_instantiation() from 16% to 9% when
idling in "Biolab Disaster". It also reduces has_binding() from 3% to
1% on the same content.
With these changes, we now actually get to idle a little bit between
game frames on my machine. :^)
It's really annoying to write `console.log(JSON.stringify(something))`
in scripts, and the output is less than easily readable.
This exposes the existing `print(Value)` function into the JS world, and
allows us to write `print(something)` and get a neat representation in
the console.
Instead of crashing on the spot, return a descriptive error that will
eventually continue its days as a javascript "InternalError" exception.
This should make random crashes with BC less likely.
This implements ordered sets using Maps with a sentinel value, and
includes some extra set tests.
Fixes#11004.
Co-Authored-By: davidot <davidot@serenityos.org>
This commit removes all exception related code:
Remove VM::exception(), VM::throw_exception() etc. Any leftover
throw_exception calls are moved to throw_completion.
The one method left is clear_exception() which is now a no-op. Most of
these calls are just to clear whatever exception might have been thrown
when handling a Completion. So to have a cleaner commit this will be
removed in a next commit.
It also removes the actual Exception and TemporaryClearException classes
since these are no longer used.
In any spot where the exception was actually used an attempt was made to
preserve that behavior. However since it is no longer tracked by the VM
we cannot access exceptions which were thrown in previous calls.
There are two such cases which might have different behavior:
- In Web::DOM::Document::interpreter() the on_call_stack_emptied hook
used to print any uncaught exception but this is now no longer
possible as the VM does not store uncaught exceptions.
- In js the code used to be interruptable by throwing an exception on
the VM. This is no longer possible but was already somewhat fragile
before as you could happen to throw an exception just before a VERIFY.
This feature had bitrotted somewhat and would trigger errors because
PrimitiveStrings were "destroyed" but because of this mode they were not
removed from the string cache. Even fixing that case running test-js
with the options still failed in more places.
Using an Optional was extremely wasteful for function objects that don't
even have a bytecode executable.
This allows ECMAScriptFunctionObject to fit in a smaller size class.
As the two types are used in exactly the same way, just make the lambda
generic over the type instead of explicitly moving them into a variant
and then visiting with a generic lambda.
This reverts most of commit ede5c9548e.
The one change not reverted is ClockWidget.h, so that the taskbar clock
can continue to notice time zone changes.
In most applications, we invoke tzset once at startup for now. Most of
these are short lived and don't need to know about time zone changes.
The exception is the ClockWidget in the taskbar. Here, we invoke tzset
each time we update the system time. This way, any time zone changes can
take effect immediately.
This allows us to load modules from scripts.
This can be dangerous as it can load arbitrary files. Because of that it
fails and throws by default. Currently, only js and JavaScriptTestRunner
enable the default hook.
This also adds tests to test-js which test module code. Because we
form a spec perspective can't "enter" a module this is the easiest way
to run tests without having to modify test-js to have special cases for
modules.
To specify modules in test-js we use the extension '.mjs' this is to
ensure the files are not executed. We do still want to lint these files
so the prettier scripts have changed to look for '.mjs' files as well.
This also refactors interpreter creation to follow
InitializeHostDefinedRealm, but I couldn't fit it in the title :^)
This allows us to follow the spec much more closely rather than being
completely ad-hoc with just the parse node instead of having all the
surrounding data such as the realm of the parse node.
The interpreter creation refactor creates the global execution context
once and doesn't take it off the stack. This allows LibWeb to take the
global execution context and manually handle it, following the HTML
spec. The HTML spec calls this the "realm execution context" of the
environment settings object.
It also allows us to specify the globalThis type, as it can be
different from the global object type. For example, on the web, Window
global objects use a WindowProxy global this value to enforce the same
origin policy on operations like [[GetOwnProperty]].
Finally, it allows us to directly call Program::execute in perform_eval
and perform_shadow_realm_eval as this moves
global_declaration_instantiation into Interpreter::run
(ScriptEvaluation) as per the spec.
Note that this doesn't evalulate Source Text Modules yet or refactor
the bytecode interpreter, that's work for future us :^)
This patch was originally build by Luke for the environment settings
object change but was also needed for modules. So I (davidot) have
modified it with the new completion changes and setup for that.
Co-authored-by: davidot <davidot@serenityos.org>
Instead of making it a void function, checking for an exception, and
then receiving the relevant result via VM::last_value(), we can
consolidate all of this by using completions.
This allows us to remove more uses of VM::exception(), and all uses of
VM::last_value().
This includes:
- Parsing proper LabelledStatements with try_parse_labelled_statement()
- Removing LabelableStatement
- Implementing the LoopEvaluation semantics via loop_evaluation() in
each IterationStatement subclass; and IterationStatement evaluation
via {For,ForIn,ForOf,ForAwaitOf,While,DoWhile}Statement::execute()
- Updating ReturnStatement, BreakStatement and ContinueStatement to
return the appropriate completion types
- Basically reimplementing TryStatement and SwitchStatement according to
the spec, using completions
- Honoring result completion types in AsyncBlockStart and
OrdinaryCallEvaluateBody
- Removing any uses of the VM unwind mechanism - most importantly,
VM::throw_exception() now exclusively sets an exception and no longer
triggers any unwinding mechanism.
However, we already did a good job updating all of LibWeb and userland
applications to not use it, and the few remaining uses elsewhere don't
rely on unwinding AFAICT.
In the end this is a nicer API than having separate has_{value,target}()
and having to check those first, and then making another Optional from
the unwrapped value:
completion.has_value() ? completion.value() : Optional<Value> {}
// ^^^^^^^^^^^^^^^^^^
// Implicit creation of non-empty Optional<Value>
This way we need to unwrap the optional ourselves, but can easily pass
it to something else as well.
This is in anticipation of the AST using completions :^)
The spec has a note stating that resolve binding will always return a
reference whose [[ReferencedName]] field is name. However this is not
correct as the underlying method GetIdentifierReference may throw on
env.HasBinding(name) thus it can throw. However, there are some
scenarios where it cannot throw because the reference is known to exist
in that case we use MUST with a comment.
This is partially a revert of commits:
10a8b6d411561b67a1ad
Rather than adding the prot_exec pledge requried to use dlopen(), we can
link directly against LibUnicodeData in applications that we know need
that library.
This might make the dlopen() dance a bit unnecessary. The same purpose
might now be fulfilled with weak symbols. That can be revisted next, but
for now, this at least removes the potential security risk of apps like
the Browser having prot_exec privileges.
This implements:
- console.group()
- console.groupCollapsed()
- console.groupEnd()
In the Browser, we use `<details>` for the groups, which is not actually
implemented yet, so groups are always open.
In the REPL, groups are non-interactive, but still indent any output.
This looks weird since the console prompt and return values remain on
the far left, but this matches what Node does so it's probably fine. :^)
I expect `console.group()` is not used much outside of browsers.
The spec very kindly defines `Printer` as accepting
"Implementation-specific representations of printable things such as a
stack trace or group." for the `args`. We make use of that here by
passing the `Trace` itself to `Printer`, instead of having to produce a
representation of the stack trace in advance and then pass that to
`Printer`. That both avoids the hassle of tracking whether the data has
been html-encoded or not, and means clients don't have to implement the
whole `trace()` algorithm, but only the code needed to output the trace.
The `CountReset` log level is displayed as a warning, since the message
is always to warn that the counter doesn't exist. This is also in line
with the table at https://console.spec.whatwg.org/#loglevel-severity
This implements the Logger and Printer abstract operations defined in
the console spec, and stubs out the Formatter AO. These are then used
for the "output a categorized log message" functions.
