We now leverage the VM's promise rejection tracker callbacks and print a
warning in either of these cases:
- A promise was rejected without any handlers
- A handler was added to an already rejected promise
Almost a year after first working on this, it's finally done: an
implementation of Promises for LibJS! :^)
The core functionality is working and closely following the spec [1].
I mostly took the pseudo code and transformed it into C++ - if you read
and understand it, you will know how the spec implements Promises; and
if you read the spec first, the code will look very familiar.
Implemented functions are:
- Promise() constructor
- Promise.prototype.then()
- Promise.prototype.catch()
- Promise.prototype.finally()
- Promise.resolve()
- Promise.reject()
For the tests I added a new function to test-js's global object,
runQueuedPromiseJobs(), which calls vm.run_queued_promise_jobs().
By design, queued jobs normally only run after the script was fully
executed, making it improssible to test handlers in individual test()
calls by default [2].
Subsequent commits include integrations into LibWeb and js(1) -
pretty-printing, running queued promise jobs when necessary.
This has an unusual amount of dbgln() statements, all hidden behind the
PROMISE_DEBUG flag - I'm leaving them in for now as they've been very
useful while debugging this, things can get quite complex with so many
asynchronously executed functions.
I've not extensively explored use of these APIs for promise-based
functionality in LibWeb (fetch(), Notification.requestPermission()
etc.), but we'll get there in due time.
[1]: https://tc39.es/ecma262/#sec-promise-objects
[2]: https://tc39.es/ecma262/#sec-jobs-and-job-queues
This utility traces the route packets take to a user specified host.
QEMU user networking (the type of networking we currently have setup)
does not support sending "real" raw IPv4 packets, and as such we cant
specify a custom TTL value. As a result, this utility will only work
on real hardware, qemu setup with tun networking (requires root) and
other hypervisors that support bridged adapters (VirtualBox/VMWare).
Instead of crashing on a missing input file, looping forever on an
invalid gzip compressed file, and crashing on permissions issues in
the output file, handle all issues gracefully by logging and returning.
and customizable indentation level
An example: cat /proc/net/adapters | jp
Another example: cat /proc/all | jp -i 2 (indents are set to 2 spaces, instead of 4 by default)
This parser should be a little bit more modern and a little more
resilient to zip files from other operating systems. As a side
effect we now also support extracting zip files that are using
DEFLATE compression (using our own LibCompress).
If in 'foo(); bar();' bar fails, we'd get the error of that and then
foo's return value - that's probably not something anyone expects.
Also make sure to return non-success so the process will exit with 1.
Very incompressible data could sometimes produce no backreferences
which would result in no distance huffman code being created (as it
was not needed), so VERIFY the code exists only if it is actually
needed for writing the stream.
This completes our tar utility by implementing the -c option
for archive creation using TarOutputStream and optionally
GzipCompressor for compression via the -z option.
We can't always rely on the initial URL's path(), so use either the
user-specified argument or the URL path for determining the realpath,
depending on whether we got a file:// URL argument.
Fixes#4950.
