The `JsRuntimeState` struct stores a number of JS callbacks that are
used either in the event loop or when interacting with V8. Some of these
callback fields are vectors of callbacks, and therefore could plausibly
store at least one callback per realm. However, some of those fields are
`Option<v8::Global<v8::Function>>`, which would make the callbacks set
by a realm override the one that might have been set by a different
realm.
As it turns out, all of the current such optional callbacks
(`js_promise_reject_cb`, `js_format_exception_cb` and
`js_wasm_streaming_cb`) are only used from inside a realm, and therefore
this change makes it so such callbacks can only be set from inside a
realm, and will only affect that realm.
This is a reland of #15599.
Towards #13239.
Currently realms are supported on `deno_core`, but there was no support
for async ops anywhere other than the main realm. The main issue is that
the `js_recv_cb` callback, which resolves promises corresponding to
async ops, was only set for the main realm, so async ops in other realms
would never resolve. Furthermore, promise ID's are specific to each
realm, which meant that async ops from other realms would result in a
wrong promise from the main realm being resolved.
This change takes the `ContextState` struct added in #17050, and adds to
it a `js_recv_cb` callback for each realm. Combined with the fact that
that same PR also added a list of known realms to `JsRuntimeState`, and
that #17174 made `OpCtx` instances realm-specific and had them include
an index into that list of known realms, this makes it possible to know
the current realm in the `queue_async_op` and `queue_fast_async_op`
methods, and therefore to send the results of promises for each realm to
that realm, and prevent the ID's from getting mixed up.
Additionally, since promise ID's are no longer unique to the isolate,
having a single set of unrefed ops doesn't work. This change therefore
also moves `unrefed_ops` from `JsRuntimeState` to `ContextState`, and
adds the lengths of the unrefed op sets for all known realms to get the
total number of unrefed ops to compare in the event loop.
This PR is a reland of #14734 after it was reverted in #16366, except
that `ContextState` and `JsRuntimeState::known_realms` were previously
relanded in #17050. Another significant difference with the original PR
is passing around an index into `JsRuntimeState::known_realms` instead
of a `v8::Global<v8::Context>` to identify the realm, because async op
queuing in fast calls cannot call into V8, and therefore cannot have
access to V8 globals. This also simplified the implementation of
`resolve_async_ops`.
Co-authored-by: Luis Malheiro <luismalheiro@gmail.com>
This commit changes signature of "deno_core::ModuleLoader::resolve" to pass
an enum indicating whether or not we're resolving a specifier for dynamic import.
Additionally "CliModuleLoader" was changes to store both "parent permissions" (or
"root permissions") as well as "dynamic permissions" that allow to check for permissions
in top-level module load an dynamic imports.
Then all code paths that have anything to do with Node/npm compat are now checking
for permissions which are passed from module loader instance associated with given
worker.
This commit fixes handling of rejected promises in dynamic imports
evaluation.
Previously we were running callbacks for next ticks and macrotasks
_before_ polling
dynamic imports and checked for unhandled rejections immediately after.
This is wrong,
as `unhandledrejection` event is dispatched and its callbacks are run as
macrotasks.
This commit changes order of actions performed by the event loop to
following:
- poll async ops
- poll dynamic imports
- run next tick callbacks
- run macrotask callbacks
- check for unhandled promise rejections
Although PR #16366 did not fully revert `deno_core`'s support for
realms, since `JsRealm` still existed after that, it did remove the
`ContextState` struct, originally introduced in #14734. This change made
`js_build_custom_error_cb`, among other properties, a per-runtime
callback, rather than per-realm, which cause a bug where errors thrown
from an op would always be constructed in the main realm, rather than in
the current one.
This change adds back `ContextState` to fix this bug, adds back the
`known_realms` field of `JsRuntimeState` (needed to be able to drop the
callback when snapshotting), and also relands #14750, which adds the
`js_realm_sync_ops` test for this bug that was removed in #16366.
- `JsRuntime::built_from_snapshot` was removed because it was redundant
with `JsRuntime::snapshot_options`.
- Updates to stale documentation of `JsRuntime::create_realm`.
- `JsRuntime::create_realm` now calls `JsRuntime::init_extension_js`
unconditionally, since if the runtime was built from a snapshot,
`init_extension_js` will be a no-op.
- Typo fix in the documentation for `JsRealm`.
This commit updates unhelpful messages that are raised when event loop
stalls on unresolved top-level promises.
Instead of "Module evaluation is still pending but there are no pending
ops or dynamic imports. This situation is often caused by unresolved
promises." and "Dynamically imported module evaluation is still pending
but there are no pending ops. This situation is often caused by
unresolved promises." we are now printing a message like:
error: Top-level await promise never resolved
[SOURCE LINE]
^
at [FUNCTION NAME] ([FILENAME])
eg:
error: Top-level await promise never resolved
await new Promise((_resolve, _reject) => {});
^
at <anonymous>
(file:///Users/ib/dev/deno/cli/tests/testdata/test/unresolved_promise.ts:1:1)
Co-authored-by: David Sherret <dsherret@users.noreply.github.com>
This commit allows to execute more JS code from extensions when
creating a snapshot from an existing snapshot.
"deno_core::RuntimeOptions::extensions_with_js" field was added
that is used to pass a list of extensions whose both "ops" and
associated JS source should be executed upon start.
Co-authored-by: crowlkats <crowlkats@toaxl.com>
This commit changes "JsRuntime" to send "executionContextDestroyed"
notification when the program finishes and shows a prompt informing
that runtime is waiting for inspector to disconnect.
With trial and error I found that most debuggers expect "isDefault" to be sent
in "auxData" field of "executionContextCreated" notification. This stems from
the fact that Node.js sends this data and eg. VSCode requires it to close
connection to the debugger when the program finishes execution.
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Implements fast scheduling of deferred op futures.
```rs
#[op(fast)]
async fn op_read(
state: Rc<RefCell<OpState>>,
rid: ResourceId,
buf: &mut [u8],
) -> Result<u32, Error> {
// ...
}
```
The future is scheduled via a fast API call and polled by the event loop
after being woken up by its waker.
* Use stack allocated array for 16 promises and spill rest to heap. the
exact number can change, maybe 128? (tokio's coop budget limit)
* Avoid v8::Global::clone for global context.
* Do not open global opresolve when its not needed.
V8's JIT can do a better job knowing the argument count and also enable
fast call path (in future).
This also lets us call async ops without `opAsync`:
```js
const { ops } = Deno.core;
await ops.op_void_async();
```
this patch: 4405286 ops/sec
main: 3508771 ops/sec
When an op returns an `anyhow` error with a cause (usually added using
the `.context()` method), the `Error` thrown into JavaScript contains
only the message of the outernmost error in the chain.
This PR simply changes the formatting of `anyhow::Error` from `"{}"` to
`"{:#}"`:
This significantly improves errors for code that embeds Deno and defines
custom ops. For example, in
[chiselstrike/chiselstrike](https://github.com/chiselstrike/chiselstrike),
this PR improves an error message like
```
Error: could not plan migration
```
to
```
Error: could not plan migration: could not migrate table for entity "E": could not add column for field "title": the field does not have a default value
```
example writeFile benchmark:
```
# before
time 188 ms rate 53191
time 168 ms rate 59523
time 167 ms rate 59880
time 166 ms rate 60240
time 168 ms rate 59523
time 173 ms rate 57803
time 183 ms rate 54644
# after
time 157 ms rate 63694
time 152 ms rate 65789
time 151 ms rate 66225
time 151 ms rate 66225
time 152 ms rate 65789
```
This revert has been discussed at length out-of-band (including with
@andreubotella). The realms work in impeding ongoing event loop and
performance work. We very much want to land realms but it needs to wait
until these lower-level refactors are complete. We hope to bring realms
back in a couple weeks.
This PR implements the NAPI for loading native modules into Deno.
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Co-authored-by: DjDeveloper <43033058+DjDeveloperr@users.noreply.github.com>
Co-authored-by: Ryan Dahl <ry@tinyclouds.org>
Several functions used for handling of dynamic imports and "import.meta"
object were not registered as external references and caused V8 to crash
during snapshotting. These functions are now registered as external refs
and aborts are no longer happening.
The `JsRuntimeState` struct stores a number of JS callbacks that are
used either in the event loop or when interacting with V8. Some of
these callback fields are vectors of callbacks, and therefore could
plausibly store at least one callback per realm. However, some of
those fields are `Option<v8::Global<v8::Function>>`, which would make
the callbacks set by a realm override the one that might have been set
by a different realm.
As it turns out, all of the current such optional callbacks
(`js_promise_reject_cb`, `js_format_exception_cb` and
`js_wasm_streaming_cb`) are only used from inside a realm, and
therefore this change makes it so such callbacks can only be set from
inside a realm, and will only affect that realm.
Welcome to better optimised op calls! Currently opSync is called with parameters of every type and count. This most definitely makes the call megamorphic. Additionally, it seems that spread params leads to V8 not being able to optimise the calls quite as well (apparently Fast Calls cannot be used with spread params).
Monomorphising op calls should lead to some improved performance. Now that unwrapping of sync ops results is done on Rust side, this is pretty simple:
```
opSync("op_foo", param1, param2);
// -> turns to
ops.op_foo(param1, param2);
```
This means sync op calls are now just directly calling the native binding function. When V8 Fast API Calls are enabled, this will enable those to be called on the optimised path.
Monomorphising async ops likely requires using callbacks and is left as an exercise to the reader.
Pull request #14019 enabled initial support for realms, but it did not
include support for async ops anywhere other than the main realm. The
main issue was that the `js_recv_cb` callback, which resolves promises
corresponding to async ops, was only set for the main realm, so async
ops in other realms would never resolve. Furthermore, promise ID's are
specific to each realm, which meant that async ops from other realms
would result in a wrong promise from the main realm being resolved.
This change creates a `ContextState` struct, similar to
`JsRuntimeState` but stored in a slot of each `v8::Context`, which
contains a `js_recv_cb` callback for each realm. Combined with a new
list of known realms, which stores them as `v8::Weak<v8::Context>`,
and a change in the `#[op]` macro to pass the current context to
`queue_async_op`, this makes it possible to send the results of
promises for different realms to their realm, and prevent the ID's
from getting mixed up.
Additionally, since promise ID's are no longer unique to the isolate,
having a single set of unrefed ops doesn't work. This change therefore
also moves `unrefed_ops` from `JsRuntimeState` to `ContextState`, and
adds the lengths of the unrefed op sets for all known realms to get
the total number of unrefed ops to compare in the event loop.
Co-authored-by: Luis Malheiro <luismalheiro@gmail.com>
Update "deno_core" to not forward rejection of top level module
if it was already handled by appropriate handlers.
Co-authored-by: Colin Ihrig cjihrig@gmail.com
The `op_event_loop_has_more_work` op, introduced in #14830, duplicates
code from `JsRuntime::poll_event_loop`. That PR also added the unused
method `JsRuntime::event_loop_has_work`, which is another duplication
of that same code, and which isn't used anywhere.
This change deduplicates this by renaming
`JsRuntime::event_loop_has_work` to `event_loop_pending_state`, and
making it the single place to determine what in the event loop is
pending. This result is then returned in a struct which is used both
in the event loop and in the `op_event_loop_has_more_work` op.
Currently almost every `JsRealm` method has a `&mut JsRuntime`
argument. This argument, however, is only used to get the runtime's
corresponding isolate. Given that a mutable reference to the
corresponding `v8::Isolate` can be reached from many more places than
a mutable reference to the `JsRuntime` (for example, by derefing a V8
scope), changing that will make `JsRealm` usable from many more places
than it currently is.
When a dynamically imported module gets resolved, any code that comes after an
await import() to that module will continue running. However, if that is the
last code in the evaluation of another dynamically imported module, that second
module will not resolve until the next iteration of the event loop, even though
it does not depend on the event loop at all.
When the event loop is being blocked by a long-running operation, such as a
long-running timer, or by an async op that might never end, such as with workers
or BroadcastChannels, that will result in the second dynamically imported module
not being resolved for a while, or ever.
This change fixes this by running the dynamic module loading steps in a loop
until no more dynamic modules can be resolved.
Keep a cache for source maps and source lines.
We sort of already had a cache argument for source map lookup
functions but we just passed an empty map instead of storing it.
Extended it to cache source line lookups as well and plugged it
into runtime state.
This commit adds "Deno.core.setFormatExceptionCallback" which
can be used to provide custom formatting for errors. It is useful
in cases when user throws something that is non-Error (eg.
a string, plain object, etc).
This reverts commit 10e50a1207
Alternative to #13217, IMO the tradeoffs made by #10786 aren't worth it.
It breaks abstractions (crates being self-contained, deno_core without snapshotting etc...) and causes pain points / gotchas for both embedders & devs for a relatively minimal gain in incremental build time ...
Closes #11030
This commit:
- removes "fmt_errors::PrettyJsError" in favor of "format_js_error" fn
- removes "deno_core::JsError::create" and
"deno_core::RuntimeOptions::js_error_create_fn"
- adds new option to "deno_runtime::ops::worker_host::init"
This commit adds tentative support for multiple realms in "deno_core".
It adds the "JsRealm" API that adds methods like "JsRuntime"'s
"handle_scope", "global_object" and "execute_script" specific to the realm.
The following transformations gradually faced by "JsError" have all been
moved up front to "JsError::from_v8_exception()":
- finding the first non-"deno:" source line;
- moving "JsError::script_resource_name" etc. into the first error stack
in case of syntax errors;
- source mapping "JsError::script_resource_name" etc. when wrapping
the error even though the frame locations are source mapped earlier;
- removing "JsError::{script_resource_name,line_number,start_column,end_column}"
entirely in favour of "js_error.frames.get(0)".
We also no longer pass a js-side callback to "core/02_error.js" from cli.
I avoided doing this on previous occasions because the source map lookups
were in an awkward place.
This note about how `v8::SnapshotCreator::create_blob` must not be
called from a `HandleScope` stopped being relevant in #6801, and was
now attached to code that had nothing to do with `HandleScope`s.
Streamlines a common middleware pattern and provides foundations for avoiding variably sized v8::ExternalReferences & enabling fully monomorphic op callpaths
