This commit abstracts out the specifics of the underlying system calls
FS operations behind a new `FileSystem` and `File` trait in the
`ext/fs` extension.
This allows other embedders to re-use ext/fs, but substituting in a
different FS backend.
This is likely not the final form of these traits. Eventually they will
be entirely `deno_core::Resource` agnostic, and will live in a seperate
crate.
---------
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Turns out `autoprefixer` is a better reproduction case then
`microbundle`.
Fixes #18535
Fixes #18600
---------
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
This commit adds op_read_sync and op_write_sync to core. These ops are
similar to op_read and op_write, but they are synchronous. Just like the
async ops, they operate on generic `deno_core::Resource` objects. These
now have new `read_byob_sync` and `write_sync` methods, with default
implementations throwing "NotSupported" errors, just like the async
counterparts.
There are no `write_all` or `read` equivalents, because the
optimizations they unlock are not useful in synchronous contexts.
This is a follow-on to the earlier work in reducing string copies,
mainly focused on ensuring that ASCII strings are easy to provide to the
JS runtime.
While we are replacing a 16-byte reference in a number of places with a
24-byte structure (measured via `std::mem::size_of`), the reduction in
copies wins out over the additional size of the arguments passed into
functions.
Benchmarking shows approximately the same if not slightly less wallclock
time/instructions retired, but I believe this continues to open up
further refactoring opportunities.
This commit changes "node:http" module to use "Deno.serveHttp" API
instead of "Deno.serve" API.
---------
Co-authored-by: Matt Mastracci <matthew@mastracci.com>
This commit adds new "op_http_upgrade_early", that allows to hijack
existing "Deno.HttpConn" acquired from "Deno.serveHttp" API
and performing a Websocket upgrade on this connection.
This is not a public API and is meant to be used internally in the
"ext/node" polyfills for "http" module.
---------
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
This commit adds a new core API `opAsync2` to call an async op with
atmost 2 arguments. Spread argument iterators has a pretty big perf hit
when calling ops.
| name | avg msg/sec/core |
| --- | --- |
| 1.32.1 | `127820.750000` |
| #18506 | `140079.000000` |
| #18506 + #18509 | `150104.250000` |
| #18506 + #18509 + this | `157340.000000` |
Use u16 to represent the kind of event (0 - 6) & event code > 6 is
treated as the close code. This way we can represent all events + the
close code in a single JS number. This is safe because (as per RFC 6455)
close code from 0-999 are reserved & not used.
| name | avg msg/sec/core |
| --- | --- |
| deno_main | `127820.750000` |
| deno #18506 | `140079.000000` |
| deno #18506 + this | `150104.250000` |
This commit updates the `Deno.Kv` API to return the new commited
versionstamp for the mutated data from `db.set` and `ao.commit`. This is
returned in the form of a `Deno.KvCommitResult` object that has a
`versionstamp` property.
This reverts commit a3529d0232.
This change made debugging Node tests very hard - `AssertionError` is
now printed as `[Circular *1]` giving no visibility what failed.
We need to align two implementations together and remove this one then.
This commit adds associated type to "NodeEnv" trait, called "Fs".
The "Fs" type has a trait bound on "NodeFs", which specifies APIs
required for all ops and resolution APIs to function.
A "RealFs" implementation of "NodeFs" is exported from the "deno_node"
crate, that provides a default implementation for the trait.
All code in "deno_node" extension was changed to use the "NodeFs" trait
to handle file system operations, instead of relying on APIs from the
standard library.
Currently the `processenv` feature is not explicitly requested by
`deno_io`, however it is using the `processenv` module. This will
prevent downstream users from building on Windows.
I'd assume that this doesn't popup in Deno itself since another crate is
enabling this feature.
This commit changes the type parameter for "deno_node" extension, from
`P: NodePermission` to `Env: NodeEnv`.
`NodeEnv` is a new trait that has associated type `P: NodePermission`.
This is a stepping stone to support swappable file system for the
extension, that will be added as a second associated type to the
`NodeEnv` trait.
Towards #18455
This commit implements `checkPrimeSync` and `checkPrime` in node:crypto
using the Miller-Rabin primality test (fun fact: it actually is a test
for composite numbers)
It first compares the candidate against many known small primes and if
not, proceeds to run the Miller-Rabin primality test.
http://nickle.org/examples/miller-rabin.5c used as reference
implementation.
This internal node hook is used by libraries such as `ts-node` when used
as a require hook `node -r ts-node/register`. That combination is often
used with test frameworks like `mocha` or `jasmine`.
We had a reference to `Module._preloadModules` in our code, but the
implementation was missing. While fixing this I also noticed that the
`fakeParent` module that we create internally always threw because of
the `pathDirname` check on the module id in the constructor of `Mdoule`.
So this code path was probably broken for a while.
```txt
✖ ERROR: Error: Empty filepath.
at pathDirname (ext:deno_node/01_require.js:245:11)
at new Module (ext:deno_node/01_require.js:446:15)
at Function.Module._resolveFilename (ext:deno_node/01_require.js:754:28)
at Function.resolve (ext:deno_node/01_require.js:1015:19)
```
Since we can preserve ops in the snapshot these days, we no longer
need to have "Deno[Deno.internal].nodeUnstable" namespace.
Instead, various built-in Node.js modules can use appropriate APIs
directly.
This commit adds the `crypto.createSecretKey` API.
Key management: This follows the same approach as our WebCrypto
CryptoKey impl where we use WeakMap for storing key material and a
handle is passed around, such that (only internal) JS can access the key
material and we don't have to explicitly close a Rust resource.
As a result, `createHmac` now accepts a secret KeyObject.
Closes https://github.com/denoland/deno/issues/17844
This will improve diagnostics and catch any non-ASCII extension code
early.
This will use `debug_assert!` rather than `assert!` to avoid runtime
costs, and ensures (in debug_assert mode only) that all extension source
files are ASCII as we load them.
No need for two almost identical implementations of the same thing
---------
Co-authored-by: Yoshiya Hinosawa <stibium121@gmail.com>
Co-authored-by: Aapo Alasuutari <aapo.alasuutari@gmail.com>
Previously the mapping between `AnyValue::Bool` and `KeyPart::Bool` was
inverted.
This patch also allows using the empty key `[]` as range start/end to
`snapshot_read`.
Currently `Deno.openKv(":memory:")` requests read+write permissions for
`./:memory:` even though no file is read or written. Also added some
guards for special sqlite paths that were unintentionally opted into.
This commit adds unstable "Deno.openKv()" API that allows to open
a key-value database at a specified path.
---------
Co-authored-by: Luca Casonato <hello@lcas.dev>
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Reduce the number of copies and allocations of script code by carrying
around ownership/reference information from creation time.
As an advantage, this allows us to maintain the identity of `&'static
str`-based scripts and use v8's external 1-byte strings (to avoid
incorrectly passing non-ASCII strings, debug `assert!`s gate all string
reference paths).
Benchmark results:
Perf improvements -- ~0.1 - 0.2ms faster, but should reduce garbage
w/external strings and reduces data copies overall. May also unlock some
more interesting optimizations in the future.
This requires adding some generics to functions, but manual
monomorphization has been applied (outer/inner function) to avoid code
bloat.
This PR changes the inspect result of anonymous functions from
`[Function]` to `[Function (anonymous)]`. This behavior is aligned
to `util.inspect` of Node.js.
Moving some code around in `ext/node` is it's a bit better well defined
and makes it possible for others to embed it.
I expect to see no difference in startup perf with this change.
These functions don't need to be async, as they are only calling
synchronous JavaScript code. As a follow up, all 3 functions
should be merge together - this will reduce roundtrips for
calling V8 from Rust, which is somewhat expensive
This commit changes the build process in a way that preserves already
registered ops in the snapshot. This allows us to skip creating hundreds of
"v8::String" on each startup, but sadly there is still some op registration
going on startup (however we're registering 49 ops instead of >200 ops).
This situation could be further improved, by moving some of the ops
from "runtime/" to a separate extension crates.
---------
Co-authored-by: Divy Srivastava <dj.srivastava23@gmail.com>
Follow-up to #18210:
* we are passing the generated `cfg` object into the state function
rather than passing individual config fields
* reduce cloning dramatically by making the state_fn `FnOnce`
* `take` for `ExtensionBuilder` to avoid more unnecessary copies
* renamed `config` to `options`
This implements two macros to simplify extension registration and centralize a lot of the boilerplate as a base for future improvements:
* `deno_core::ops!` registers a block of `#[op]`s, optionally with type
parameters, useful for places where we share lists of ops
* `deno_core::extension!` is used to register an extension, and creates
two methods that can be used at runtime/snapshot generation time:
`init_ops` and `init_ops_and_esm`.
---------
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
This PR _**temporarily**_ removes WebGPU (which has behind the
`--unstable` flag in Deno), due to performance complications due to its
presence.
It will be brought back in the future; as a point of reference, Chrome
will ship WebGPU to stable on 26/04/2023.
---------
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
This commit adds support for retrieving `dev` information
when stating files on Windows.
Additionally `Deno.FileInfo` interfaces was changed to always
return 0 for fields that we don't retrieve information for on Windows.
Closes https://github.com/denoland/deno/issues/18053
---------
Co-authored-by: David Sherret <dsherret@gmail.com>
These methods are confusing because the arguments are backwards. I feel
like they should have never been added to `Option<T>` and that clippy
should suggest rewriting to
`map(...).unwrap_or(...)`/`map(...).unwrap_or_else(|| ...)`
https://github.com/rust-lang/rfcs/issues/1025
This commit changes "deno_core" to not rely on implicitly calling
"std::env::current_dir()" when resolving module specifiers using
APIs from "deno_core::modules_specifier".
Supersedes https://github.com/denoland/deno/pull/15454
This tweaks the signature of `request_builder_hook` in order to support
fallible hooks.
The rationale for this is mostly on two sides:
* it allows a hook to inspect and possibly drop an outgoing request
(e.g. for policying purposes), bubbling up a detailed error message to
the user.
* it wires into newer `reqwest` API which allows to split and then
reassemble a `RequestBuilder`, although only in a fallible way
(https://github.com/seanmonstar/reqwest/pull/1770)
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This commit replaces `pin_mut!` macro with `pin!` macro that has been
provided from std since Rust 1.68.0.
With the std version we can not only expect its stability but also pass
an expression (rather than identifier) as an argument to the macro.
This commit removes "deno_core::RuntimeOptions::extensions_with_js".
Now it's embedders' responsibility to properly register extensions
that will not contains JavaScript sources when running from an existing
snapshot.
Prerequisite for https://github.com/denoland/deno/pull/18080
This commit partially reverts changes from
https://github.com/denoland/deno/pull/18095.
Turns out I made a mistake that became apparent when working
on removing "RuntimeOptions::extensions_with_js" in a follow up.
This commit splits "<ext_name>::init" functions into "init_ops" and
"init_ops_and_esm". That way we don't have to construct list of
ESM sources on each startup if we're running with a snapshot.
In a follow up commit "deno_core" will be changed to not have a split
between "extensions" and "extensions_with_js" - it will be embedders'
responsibility to pass appropriately configured extensions.
Prerequisite for https://github.com/denoland/deno/pull/18080
This commit changes how "unload" event is handled - before
this commit an event listener was added unconditionally in
the runtime bootstrapping function, which for some reason was
very expensive (0.3ms). Instead of adding an event listener,
a check was added to "dispatchEvent" function that performs
the same action (so it's only called if there's an event dispatched).
This commit renames "deno_core::InternalModuleLoader" to
"ExtModuleLoader" and changes the specifiers used by the
modules loaded from this loader to "ext:".
"internal:" scheme was really ambiguous and it's more characters than
"ext:", which should result in slightly smaller snapshot size.
Closes https://github.com/denoland/deno/issues/18020
Since we are snapshotting extension source at build time, there's no
need to define list of sources for the extension at runtime.
This commit changes "deno_node" extension by removing "init_polyfill"
function in favor of "init_polyfill_ops_and_esm()" and "init_polyfill_ops()".
The former is used during snapshot and when "deno_runtime" is compiled
with "dont_create_runtime_snapshot" cargo feature flag. The latter is used
when running a worker from an existing snapshot.
This is a start of a bigger refactor to all extensions - thanks to this
change, we don't have to iterate over all defined source files for extension at
runtime, and because of that we don't have to create a filepath for each of the
source files. It's not a big deal, but we are iterating over 300 files on each start,
and concatenating 3 strings before creating a "PathBuf" for ~200 of them.
This is already visible on the startup flamegraphs and should be avoided.
There's no point for this API to expect result. If something fails it should
result in a panic during build time to signal to embedder that setup is
wrong.
This API is required by several extensions like "ext/node", "ext/ffi"
and also FS APIs that we want to move to a separate crate. Because
of that "pathFromURL" API was moved to "deno_web" extension so
other extension crates can rely on it.
This commit changes "InternalModuleLoader" from "deno_core" to
store a list of used modules during snapshotting. If a module was not
used during snapshotting "InternalModuleLoader" will panic in its "Drop"
handler signaling to the embedder that they made a mistake somewhere.
We use information about build in several extension crates like
"ext/node" or "runtime/". In an effort to move "fs" APIs to a separate
crate it is a prerequisite to have this information available outside
of the "runtime/" crate.
This commit moves definition of "build" object to "Deno.core" that is
later forwarded to "Deno.build".
Join two independent ops into one. A fast impl of one + a slow callback
of another. Here's an example showing optimized paths for latin-1 via
fast call and the next-best fallback using V8 apis.
```rust
#[op(v8)]
fn op_encoding_encode_into_fallback(
scope: &mut v8::HandleScope,
input: serde_v8::Value,
// ...
#[op(fast, slow = op_encoding_encode_into_fallback)]
fn op_encoding_encode_into(
input: Cow<'_, str>,
// ...
```
Benchmark results of the fallback path:
```
time target/release/deno run -A --unstable ./cli/tests/testdata/benches/text_encoder_into_perf.js
________________________________________________________
Executed in 70.90 millis fish external
usr time 57.76 millis 0.23 millis 57.53 millis
sys time 17.02 millis 1.28 millis 15.74 millis
target/release/deno_main run -A --unstable ./cli/tests/testdata/benches/text_encoder_into_perf.js
________________________________________________________
Executed in 154.00 millis fish external
usr time 67.14 millis 0.26 millis 66.88 millis
sys time 38.82 millis 1.47 millis 37.35 millis
```
JavaScript APIs from "runtime/js/40_files.js" combined abstractions
for stdio streams ("Stdout", "Stderr", "Stdin") and file system file
("File", "FsFile"). APIs from "runtime/js/40_read_file.js" and
"runtime/js/40_write_file.js" were implemented using ops from
"runtime/ops/fs.rs".
This file was removed and relevant APIs were moved to "deno_io/12_io.js"
and "runtime/js/30_fs.js".
This work is meant to enable factoring out "deno_fs" crate.
This commit changes "include_js_files!" macro from "deno_core"
in a way that "dir" option doesn't cause specifiers to be rewritten
to include it.
Example:
```
include_js_files! {
dir "js",
"hello.js",
}
```
The above definition required embedders to use:
`import ... from "internal:<ext_name>/js/hello.js"`.
But with this change, the "js" directory in which the files are stored
is an implementation detail, which for embedders results in:
`import ... from "internal:<ext_name>/hello.js"`.
The directory the files are stored in, is an implementation detail and
in some cases might result in a significant size difference for the
snapshot. As an example, in "deno_node" extension, we store the
source code in "polyfills" directory; which resulted in each specifier
to look like "internal:deno_node/polyfills/<module_name>", but with
this change it's "internal:deno_node/<module_name>".
Given that "deno_node" has over 100 files, many of them having
several import specifiers to the same extension, this change removes
10 characters from each import specifier.
This is a super basic initial implementation. We don't create a
`node_modules/.bin` folder at the moment and add it to the PATH like we
should which is necessary to make command name resolution in the
subprocess work properly (ex. you run a script that launches another
script that then tries to launch an "npx command"... this won't work
atm).
Closes #17492
This changes npm specifiers to be handled by deno_graph and resolved to
an npm package name and version when the specifier is encountered. It
also slightly changes how npm specifier resolution occurs—previously it
would collect all the npm specifiers and resolve them all at once, but
now it resolves them on the fly as they are encountered in the module
graph.
https://github.com/denoland/deno_graph/pull/232
---------
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
This commits adds auto-discovery of "package.json" file when running
"deno run" and "deno task" subcommands. In case of "deno run" the
"package.json" is being looked up starting from the directory of the
script that is being run, stopping early if "deno.json(c)" file is found
(ie. FS tree won't be traversed "up" from "deno.json").
When "package.json" is discovered the "--node-modules-dir" flag is
implied, leading to creation of local "node_modules/" directory - we
did that, because most tools relying on "package.json" will expect
"node_modules/" directory to be present (eg. Vite). Additionally
"dependencies" and "devDependencies" specified in the "package.json"
are downloaded on startup.
This is a stepping stone to supporting bare specifier imports, but
the actual integration will be done in a follow up commit.
---------
Co-authored-by: David Sherret <dsherret@gmail.com>
This commit changes definition of "ExtensionFileSource", by changing
"code" field to being "ExtensionFileSourceCode" enum. Currently the enum
has only a single variant "IncludedInBinary". It is done in preparation
to allow embedders to decide if they want to include the source code in the
binary when snapshotting (in most cases they shouldn't do that).
In the follow up commit we'll add more variants to
"ExtensionFileSourceCode".
"include_js_files_dir!" macro was removed in favor "include_js_files!"
macro which can now accept "dir" option.
Adds two test files: "cli/tests/unit_node/process_test.ts" and
"cli/tests/unit_node/child_process_test.ts"
---------
Co-authored-by: Yoshiya Hinosawa <stibium121@gmail.com>
This PR changes Node.js/npm compatibility layer to use polyfills for
built-in Node.js
embedded in the snapshot (that are coming from "ext/node" extension).
As a result loading `std/node`, either from
"https://deno.land/std@<latest>/" or
from "DENO_NODE_COMPAT_URL" env variable were removed. All code that is
imported via "npm:" specifiers now uses code embedded in the snapshot.
Several fixes were applied to various modules in "ext/node" to make
tests pass.
---------
Co-authored-by: Yoshiya Hinosawa <stibium121@gmail.com>
Co-authored-by: Divy Srivastava <dj.srivastava23@gmail.com>
Fixes denoland#16922.
The error messages in the `ffi` module are somewhat cryptic when passing
functions that have invalid `parameters` or `result` type strings. While
the generated serializer for the `ForeignFunction` struct correctly
outputs a correct and verbose message, the user sees a far less helpful
`data did not match any variant` message instead.
The underlying cause appears to be the fallback message in the
auto-derived deserializer for untagged enums [1] generated as a result
of `ForeignSymbol` being marked as `#[serde(untagged)]` [2]. Passing an
unexpected value for `NativeType` causes it to error out while
attempting to deserialize both enum variants -- once because it's not a
match for the `ForeignStatic` variant, and once because the
`ForeignFunction` deserializer rejects the invalid type for the
parameters/return type. This is currently open as [serde
#773](https://github.com/serde-rs/serde/issues/773), and not a trivial
exercise to fix generically.
[1]
https://github.com/serde-rs/serde/blob/v0.9.7/serde_derive/src/de.rs#L730
[2] https://github.com/denoland/deno/blob/main/ext/ffi/dlfcn.rs#L102
[3] https://github.com/serde-rs/serde/issues/773
Note that the auto-generated deserializer for untagged enums uses a
private API to buffer deserializer content that we don't have access to.
Instead, we can make use of the `serde_value` crate to buffer the
values. This can likely be removed once the official buffering API lands
(see [4] and [5]). In addition, this crate pulls in `serde_json` as a
cheap way to test that the deserializer works properly.
[4] https://github.com/serde-rs/serde/issues/741
[5] https://github.com/serde-rs/serde/pull/2348
This commit moves "deno_std/node" in "ext/node" crate. The code is
transpiled and snapshotted during the build process.
During the first pass a minimal amount of work was done to create the
snapshot, a lot of code in "ext/node" depends on presence of "Deno"
global. This code will be gradually fixed in the follow up PRs to migrate
it to import relevant APIs from "internal:" modules.
Currently the code from snapshot is not used in any way, and all
Node/npm compatibility still uses code from
"https://deno.land/std/node" (or from the location specified by
"DENO_NODE_COMPAT_URL"). This will also be handled in a follow
up PRs.
---------
Co-authored-by: crowlkats <crowlkats@toaxl.com>
Co-authored-by: Divy Srivastava <dj.srivastava23@gmail.com>
Co-authored-by: Yoshiya Hinosawa <stibium121@gmail.com>
This commit stabilizes Node-API, the "--unstable" flag is no longer
required to load native extensions. "--allow-ffi" permission is still
required to load them.
Fixes https://github.com/denoland/deno/issues/17761
Tugstenite already sends a pong for a recieved ping. This automatically
happens when the socket read is being driven. From
https://github.com/snapview/tokio-tungstenite/issues/88
> You need to read from the read-side of the socket so that it
receives/handles pings, and on the next write it would then send the
corresponding pong.
Here's the source:
e1033afd95/src/protocol/mod.rs (L374-L380)
```rust
// Upon receipt of a Ping frame, an endpoint MUST send a Pong frame in
// response, unless it already received a Close frame. It SHOULD
// respond with Pong frame as soon as is practical. (RFC 6455)
if let Some(pong) = self.pong.take() {
trace!("Sending pong reply");
self.send_one_frame(stream, pong)?;
}
```
WIth this patch, all Autobahn tests from 1-8 pass. Fixed cases: 2.1,
2.2, 2.3, 2.4, 2.6, 2.9, 2.10, 2.11, 5.6, 5.7, 5.8, 5.19, 5.20
To run the test yourself, follow
https://www.notion.so/denolandinc/Autobahn-WebSocket-testsuite-723a86f450ce4823b4ef9cb3dc4c7869?pvs=4
This was not caught in the previous test case, as the response body was
smaller than the size of `HEAD` response.
This made `nwritten < responseLen` check in `writeFixedResponse` to
fail, and not trigger `op_flash_respond_async` as a result.
When the response body is larger than the `HEAD` though, as in the
updated test case (`HEAD` i 120 bytes, where our response is 300 bytes),
it would think that we still have something to send, and effectively
panic, as `op_flash_respond` already removed the request from the pool.
This change, makes the `handleResponse` function always calculate the
number of bytes to transmit when `HEAD` request is encountered.
Effectively ignoring `Content-Length` of the body, but still setting it
correctly in the request header itself.
Fixes https://github.com/denoland/deno/issues/17737
This commit moves some code around from "cli/node/mod.rs" to
"ext/node". Additionally "ext/node" was changed to factor out
"ops.rs" and "polyfill.rs" modules.
This commit does preparatory work to allow snapshotting Node.js
compatibility layer, that currently lives in `std/node`. The logic was
changed to allow loading some modules from the snapshot and
some from the remote URL.
Additionally "module_es_shim.js" that provides exports for "node:module"
is now snapshotted.
This PR refactors all internal js files (except core) to be written as
ES modules.
`__bootstrap`has been mostly replaced with static imports in form in
`internal:[path to file from repo root]`.
To specify if files are ESM, an `esm` method has been added to
`Extension`, similar to the `js` method.
A new ModuleLoader called `InternalModuleLoader` has been added to
enable the loading of internal specifiers, which is used in all
situations except when a snapshot is only loaded, and not a new one is
created from it.
---------
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Currently fast ops will always check for the alignment of a TypedArray
when getting a slice out of them. A match is then done to ensure that
some slice was received and if not a fallback will be requested.
For Uint8Arrays (and WasmMemory which is equivalent to a Uint8Array) the
alignment will always be okay. Rust probably optimises this away for the
most part (since the Uint8Array check is `x % 1 != 0`), but what it
cannot optimise away is the fast ops path's request for fallback options
parameter.
The extra parameter's cost is likely negligible but V8 will need to
check if a fallback was requested and prepare the fallback call just in
case it was. In the future the lack of a fallback may also enable V8 to
much better optimise the result handling.
For V8 created buffers, it seems like all buffers are actually always
guaranteed to be properly aligned: All buffers seem to always be created
8-byte aligned, and creating a 32 bit array or 64 bit array with a
non-aligned offset from an ArrayBuffer is not allowed. Unfortunately,
Deno FFI cannot give the same guarantees, and it is actually possible
for eg. 32 bit arrays to be created unaligned using it. These arrays
work fine (at least on Linux) so it seems like this is not illegal, it
just means that we cannot remove the alignment checking for 32 bit
arrays.
