Commit Graph

318 Commits

Author SHA1 Message Date
Devyn Cairns
1f4131532d
Deprecate register and add plugin use (#12607)
# Description

Adds a new keyword, `plugin use`. Unlike `register`, this merely loads
the signatures from the plugin cache file. The file is configurable with
the `--plugin-config` option either to `nu` or to `plugin use` itself,
just like the other `plugin` family of commands. At the REPL, one might
do this to replace `register`:

```nushell
> plugin add ~/.cargo/bin/nu_plugin_foo
> plugin use foo
```

This will not work in a script, because `plugin use` is a keyword and
`plugin add` does not evaluate at parse time (intentionally). This means
we no longer run random binaries during parse.

The `--plugins` option has been added to allow running `nu` with certain
plugins in one step. This is used especially for the `nu_with_plugins!`
test macro, but I'd imagine is generally useful. The only weird quirk is
that it has to be a list, and we don't really do this for any of our
other CLI args at the moment.

`register` now prints a deprecation parse warning.

This should fix #11923, as we now have a complete alternative to
`register`.

# User-Facing Changes

- Add `plugin use` command
- Deprecate `register`
- Add `--plugins` option to `nu` to replace a common use of `register`

# Tests + Formatting

I think I've tested it thoroughly enough and every existing test passes.
Testing nu CLI options and alternate config files is a little hairy and
I wish there were some more generic helpers for this, so this will go on
my TODO list for refactoring.

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

- [ ] Update plugins sections of book
- [ ] Release notes
2024-04-23 06:37:50 -05:00
Ian Manske
bae6d694ca
Refactor using ClosureEval types (#12541)
# Description
Adds two new types in `nu-engine` for evaluating closures: `ClosureEval`
and `ClosureEvalOnce`. This removed some duplicate code and centralizes
our logic for setting up, running, and cleaning up closures. For
example, in the future if we are able to reduce the cloning necessary to
run a closure, then we only have to change the code related to these
types.

`ClosureEval` and `ClosureEvalOnce` are designed with a builder API.
`ClosureEval` is used to run a closure multiple times whereas
`ClosureEvalOnce` is used for a one-shot closure.

# User-Facing Changes
Should be none, unless I messed up one of the command migrations.
Actually, this will fix any unreported environment bugs for commands
that didn't reset the env after running a closure.
2024-04-22 14:15:09 +08:00
Devyn Cairns
2595f31541
Overhaul the plugin cache file with a new msgpack+brotli format (#12579)
# Description

- Plugin signatures are now saved to `plugin.msgpackz`, which is
brotli-compressed MessagePack.
- The file is updated incrementally, rather than writing all plugin
commands in the engine every time.
- The file always contains the result of the `Signature` call to the
plugin, even if commands were removed.
- Invalid data for a particular plugin just causes an error to be
reported, but the rest of the plugins can still be parsed

# User-Facing Changes

- The plugin file has a different filename, and it's not a nushell
script.
- The default `plugin.nu` file will be automatically migrated the first
time, but not other plugin config files.
- We don't currently provide any utilities that could help edit this
file, beyond `plugin add` and `plugin rm`
  - `from msgpackz`, `to msgpackz` could also help
- New commands: `plugin add`, `plugin rm`

# Tests + Formatting

Tests added for the format and for the invalid handling.

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

- [ ] Check for documentation changes
- [ ] Definitely needs release notes
2024-04-21 07:36:26 -05:00
Devyn Cairns
f2169c8022
Switch plugin msgpack protocol to named format (#12580)
# Description
In conflict with the documentation, the msgpack serializer for plugins
is actually using the compact format, which doesn't name struct fields,
and is instead dependent on their ordering, rendering them as tuples.
This is not a good idea for a robust protocol even if it makes the
serialization and deserialization faster.

I expect this to have some impact on performance, but I think the
robustness is probably worth it.

Deserialization always accepts either format, so this shouldn't cause
too many incompatibilities.

# User-Facing Changes
This does technically change the protocol, but it makes it reflect the
documentation. It shouldn't break deserialization, so plugins shouldn't
necessarily need a recompile.

Performance is likely worse and I should benchmark the difference.

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-04-19 07:50:51 -05:00
Devyn Cairns
fac2f43aa4
Add an example Nushell plugin written in Nushell itself (#12574)
# Description

As suggested by @fdncred.

It's neat that this is possible, but the particularly useful part of
this is that we can actually
test it because it doesn't have any external dependencies, unlike the
python plugin.

Right now this just implements exactly the same behavior as the python
plugin, but we could have it
exercise a few more things.

Also fixes a couple of bugs:

- `.nu` plugins were not run with `nu --stdin`, so they couldn't take
input.
- `register` couldn't be called if `--no-config-file` was set, because
it would error on trying to
  update the plugin file.

# User-Facing Changes

- `nu_plugin_nu_example` plugin added.
- `register` now works in `--no-config-file` mode.

# Tests + Formatting
Tests added for `nu_plugin_nu_example`.

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

- [ ] Add the version bump to the release script just like for python
2024-04-19 09:53:30 +03:00
dependabot[bot]
9a739d9f0d
Bump rmp-serde from 1.1.2 to 1.2.0 (#12547)
Bumps [rmp-serde](https://github.com/3Hren/msgpack-rust) from 1.1.2 to
1.2.0.
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</details>
<br />


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2024-04-17 16:44:54 +08:00
Devyn Cairns
48e4448e55
Add a panic unwind handler during plugin calls (#12526)
# Description
If a panic happens during a plugin call, because it always happens
outside of the main thread, it currently just hangs Nushell because the
plugin stays running without ever producing a response to the call.

This adds a panic handler that calls `exit(1)` after the unwind finishes
to the plugin runner. The panic error is still printed to stderr as
always, and waiting for the unwind to finish helps to ensure that
anything on the stack with `Drop` behavior that needed to run still
runs, at least on that thread.

# User-Facing Changes
Panics now look like this, which is what they looked like before the
plugin behavior was moved to a separate thread:

```
thread 'plugin runner (primary)' panicked at crates/nu_plugin_example/src/commands/main.rs:45:9:
Test panic
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Error: nu:🐚:plugin_failed_to_decode

  × Plugin failed to decode: Failed to receive response to plugin call

```

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-04-16 15:00:32 +00:00
Devyn Cairns
c06ef201b7
Local socket mode and foreground terminal control for plugins (#12448)
# Description

Adds support for running plugins using local socket communication
instead of stdio. This will be an optional thing that not all plugins
have to support.

This frees up stdio for use to make plugins that use stdio to create
terminal UIs, cc @amtoine, @fdncred.

This uses the [`interprocess`](https://crates.io/crates/interprocess)
crate (298 stars, MIT license, actively maintained), which seems to be
the best option for cross-platform local socket support in Rust. On
Windows, a local socket name is provided. On Unixes, it's a path. The
socket name is kept to a relatively small size because some operating
systems have pretty strict limits on the whole path (~100 chars), so on
macOS for example we prefer `/tmp/nu.{pid}.{hash64}.sock` where the hash
includes the plugin filename and timestamp to be unique enough.

This also adds an API for moving plugins in and out of the foreground
group, which is relevant for Unixes where direct terminal control
depends on that.

TODO:

- [x] Generate local socket path according to OS conventions
- [x] Add support for passing `--local-socket` to the plugin executable
instead of `--stdio`, and communicating over that instead
- [x] Test plugins that were broken, including
[amtoine/nu_plugin_explore](https://github.com/amtoine/nu_plugin_explore)
- [x] Automatically upgrade to using local sockets when supported,
falling back if it doesn't work, transparently to the user without any
visible error messages
  - Added protocol feature: `LocalSocket`
- [x] Reset preferred mode to `None` on `register`
- [x] Allow plugins to detect whether they're running on a local socket
and can use stdio freely, so that TUI plugins can just produce an error
message otherwise
  - Implemented via `EngineInterface::is_using_stdio()`
- [x] Clean up foreground state when plugin command exits on the engine
side too, not just whole plugin
- [x] Make sure tests for failure cases work as intended
  - `nu_plugin_stress_internals` added

# User-Facing Changes
- TUI plugins work
- Non-Rust plugins could optionally choose to use this
- This might behave differently, so will need to test it carefully
across different operating systems

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [ ] Document local socket option in plugin contrib docs
- [ ] Document how to do a terminal UI plugin in plugin contrib docs
- [ ] Document: `EnterForeground` engine call
- [ ] Document: `LeaveForeground` engine call
- [ ] Document: `LocalSocket` protocol feature
2024-04-15 18:28:18 +00:00
Devyn Cairns
af72a18785
Improve error messages for plugin protocol by removing #[serde(untagged)] (#12510)
# Description

In the plugin protocol, I had used `#[serde(untagged)]` on the `Stream`
variant to make it smaller and include all of the stream messages at the
top level, but unfortunately this causes serde to make really unhelpful
errors if anything fails to decode anywhere:

```
Error: nu:🐚:plugin_failed_to_decode

  × Plugin failed to decode: data did not match any variant of untagged enum PluginOutput
```

If you are trying to develop something using the plugin protocol
directly, this error is incredibly unhelpful. Even as a user, this
basically just says 'something is wrong'. With this change, the errors
are much better:

```
Error: nu:🐚:plugin_failed_to_decode

  × Plugin failed to decode: unknown variant `PipelineDatra`, expected one of `Error`, `Signature`, `Ordering`, `PipelineData` at line 2 column 37
```

The only downside is it means I have to duplicate all of the
`StreamMessage` variants manually, but there's only 4 of them and
they're small.

This doesn't actually change the protocol at all - everything is still
identical on the wire.

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-04-14 15:55:18 +00:00
Devyn Cairns
2ae9ad8676
Copy-on-write for record values (#12305)
# Description
This adds a `SharedCow` type as a transparent copy-on-write pointer that
clones to unique on mutate.

As an initial test, the `Record` within `Value::Record` is shared.

There are some pretty big wins for performance. I'll post benchmark
results in a comment. The biggest winner is nested access, as that would
have cloned the records for each cell path follow before and it doesn't
have to anymore.

The reusability of the `SharedCow` type is nice and I think it could be
used to clean up the previous work I did with `Arc` in `EngineState`.
It's meant to be a mostly transparent clone-on-write that just clones on
`.to_mut()` or `.into_owned()` if there are actually multiple
references, but avoids cloning if the reference is unique.

# User-Facing Changes
- `Value::Record` field is a different type (plugin authors)

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [ ] use for `EngineState`
- [ ] use for `Value::List`
2024-04-14 01:42:03 +00:00
Stefan Holderbach
872945ae8e
Bump version to 0.92.3 (#12476) 2024-04-12 08:00:43 -05:00
Ian Manske
d7ba8872bf
Rename IoStream to OutDest (#12433)
# Description
I spent a while trying to come up with a good name for what is currently
`IoStream`. Looking back, this name is not the best, because it:
1. Implies that it is a stream, when it all it really does is specify
the output destination for a stream/pipeline.
2. Implies that it handles input and output, when it really only handles
output.

So, this PR renames `IoStream` to `OutDest` instead, which should be
more clear.
2024-04-09 16:48:32 +00:00
Devyn Cairns
00b3a07efe
Add GetSpanContents engine call (#12439)
# Description
This allows plugins to view the source code of spans.

Requested by @ayax79 for implementing `polars ls`. Note that this won't
really help you find the location of the span. I'm planning to add
another engine call that will return information more similar to what
shows up in the miette diagnostics, with filename / line number / some
context, but I'll want to refactor some of the existing logic to make
that happen, so it was easier to just do this first. I hope this is
enough to at least have something somewhat useful show up for `polars
ls`.

# User-Facing Changes
- Example plugin: added `example view span` command

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [ ] Add to plugin protocol reference
2024-04-09 10:02:17 -04:00
Ian Manske
7a7d43344e
Range refactor (#12405)
# Description
Currently, `Range` is a struct with a `from`, `to`, and `incr` field,
which are all type `Value`. This PR changes `Range` to be an enum over
`IntRange` and `FloatRange` for better type safety / stronger compile
time guarantees.

Fixes: #11778 Fixes: #11777 Fixes: #11776 Fixes: #11775 Fixes: #11774
Fixes: #11773 Fixes: #11769.

# User-Facing Changes
Hopefully none, besides bug fixes.

Although, the `serde` representation might have changed.
2024-04-06 09:04:56 -05:00
Devyn Cairns
0e36c43c64
Add BufWriter to ChildStdin on the plugin interface (#12419)
# Description
This speeds up writing messages to the plugin, because otherwise every
individual piece of the messages (not even the entire message) is
written with one syscall, leading to a lot of back and forth with the
kernel.

I learned this by running `strace` to debug something and saw a ton of
`write()` calls.

```nushell
# Before
1..10 | each { timeit { example seq 1 10000 | example sum } } | math avg
269ms 779µs 149ns
# After
> 1..10 | each { timeit { example seq 1 10000 | example sum } } | math avg
39ms 636µs 643ns
```

# User-Facing Changes
- Performance improvement

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-04-06 11:52:27 +08:00
Devyn Cairns
2562e306b6
Improve handling of custom values in plugin examples (#12409)
# Description
Requested by @ayax79. This makes the custom value behavior more correct,
by calling the methods on the plugin to handle the custom values in
examples rather than the methods on the custom values themselves. This
helps for handle-type custom values (like what he's doing with
dataframes).

- Equality checking in `PluginTest::test_examples()` changed to use
`PluginInterface::custom_value_partial_cmp()`
- Base value rendering for `PluginSignature` changed to use
`Plugin::custom_value_to_base_value()`
- Had to be moved closer to `serve_plugin` for this reason, so the test
for writing signatures containing custom values was removed
- That behavior should still be tested to some degree, since if custom
values are not handled, signatures will fail to parse, so all of the
other tests won't work.

# User-Facing Changes

- `Record::sort_cols()` method added to share functionality required by
`PartialCmp`, and it might also be slightly faster
- Otherwise, everything should mostly be the same but better. Plugins
that don't implement special handling for custom values will still work
the same way, because the default implementation is just a pass-through
to the `CustomValue` methods.

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-04-05 21:57:20 -05:00
Devyn Cairns
c82dfce246
Fix deadlock on PluginCustomValue drop (#12418)
# Description
Because the plugin interface reader thread can be responsible for
sending a drop notification, it's possible for it to end up in a
deadlock where it's waiting for the response to the drop notification
call.

I decided that the best way to address this is to just discard the
response and not wait for it. It's not really important to synchronize
with the response to `Dropped`, so this is probably faster anyway.

cc @ayax79, this is your issue where polars is getting stuck

# User-Facing Changes
- A bug fix
- Custom value plugin: `custom-value handle update` command

# Tests + Formatting

Tried to add a test with a long pipeline with a lot of drops and run it
over and over to reproduce the deadlock.

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-04-05 21:57:00 -05:00
Stefan Holderbach
394487b3a7
Bump version to 0.92.2 (#12402) 2024-04-05 10:24:00 -04:00
Stefan Holderbach
c00a05a762
Bump version to 0.92.1 (#12380) 2024-04-04 16:18:54 +02:00
Devyn Cairns
cbf7feef22
Make drop notification timing for plugin custom values more consistent (#12341)
# Description
This keeps plugin custom values that have requested drop notification
around during the lifetime of a plugin call / stream by sending them to
a channel that gets persisted during the lifetime of the call.

Before this change, it was very likely that the drop notification would
be sent before the plugin ever had a chance to handle the value it
received.

Tests have been added to make sure this works - see the `custom_values`
plugin.

cc @ayax79 

# User-Facing Changes
This is basically just a bugfix, just a slightly big one.

However, I did add an `as_mut_any()` function for custom values, to
avoid having to clone them. This is a breaking change.
2024-04-04 09:13:25 +02:00
Stefan Holderbach
c3428b891a
Bump version for 0.92.0 release (#12349)
- [x] `cargo hack` feature flag compatibility run
- [x] reedline released and pinned
- [x] `nu-plugin-test-support` added to release script
- [x] dependency tree checked
- [x] release notes
2024-04-02 20:50:26 +03:00
Devyn Cairns
714a0ccd24
Remove serde derive for ShellError, replace via LabeledError (#12319)
# Description

This changes the interface for plugins to always represent errors as
`LabeledError`s. This is good for altlang plugins, as it would suck for
them to have to implement and track `ShellError`. We save a lot of
generated code from the `ShellError` serde impl too, so `nu` and plugins
get to have a smaller binary size.

Reduces the release binary size by 1.2 MiB on my build configuration.

# User-Facing Changes

- Changes plugin protocol. `ShellError` no longer serialized.
- `ShellError` serialize output is different
- `ShellError` no longer deserializes to exactly the same value as
serialized

# Tests + Formatting

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

- [ ] Document in plugin protocol reference
2024-03-30 14:21:40 +01:00
Stefan Holderbach
b19da158d5
Rename Value::CustomValue to Value::Custom (#12309)
# Description
The second `Value` is redundant and will consume five extra bytes on
each transmission of a custom value to/from a plugin.

# User-Facing Changes
This is a breaking change to the plugin protocol.

The [example in the protocol
reference](https://www.nushell.sh/contributor-book/plugin_protocol_reference.html#value)
becomes

```json
{
  "Custom": {
    "val": {
      "type": "PluginCustomValue",
      "name": "database",
      "data": [36, 190, 127, 40, 12, 3, 46, 83],
      "notify_on_drop": true
    },
    "span": {
      "start": 320,
      "end": 340
    }
  }
}
```

instead of 

```json
{
  "CustomValue": {
    ...
  }
}
```


# After Submitting
Update plugin protocol reference
2024-03-27 22:10:56 +01:00
Devyn Cairns
01d30a416b
Change PluginCommand API to be more like Command (#12279)
# Description

This is something that was discussed in the core team meeting last
Wednesday. @ayax79 is building `nu-plugin-polars` with all of the
dataframe commands into a plugin, and there are a lot of them, so it
would help to make the API more similar. At the same time, I think the
`Command` API is just better anyway. I don't think the difference is
justified, and the types for core commands have the benefit of requiring
less `.into()` because they often don't own their data

- Broke `signature()` up into `name()`, `usage()`, `extra_usage()`,
`search_terms()`, `examples()`
- `signature()` returns `nu_protocol::Signature`
- `examples()` returns `Vec<nu_protocol::Example>`
- `PluginSignature` and `PluginExample` no longer need to be used by
plugin developers

# User-Facing Changes
Breaking API for plugins yet again 😄
2024-03-27 11:59:57 +01:00
Ian Manske
c747ec75c9
Add command_prelude module (#12291)
# Description
When implementing a `Command`, one must also import all the types
present in the function signatures for `Command`. This makes it so that
we often import the same set of types in each command implementation
file. E.g., something like this:
```rust
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
    ShellError, Signature, Span, Type, Value,
};
```

This PR adds the `nu_engine::command_prelude` module which contains the
necessary and commonly used types to implement a `Command`:
```rust
// command_prelude.rs
pub use crate::CallExt;
pub use nu_protocol::{
    ast::{Call, CellPath},
    engine::{Command, EngineState, Stack},
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, IntoSpanned,
    PipelineData, Record, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
};
```

This should reduce the boilerplate needed to implement a command and
also gives us a place to track the breadth of the `Command` API. I tried
to be conservative with what went into the prelude modules, since it
might be hard/annoying to remove items from the prelude in the future.
Let me know if something should be included or excluded.
2024-03-26 21:17:30 +00:00
Stefan Holderbach
e8bcfbaed1
Remove dead impl PluginEncoder for EncodingType (#12284)
Detected due to `clippy::wrong_self_convention` for `to_str`

# Breaking change to plugin authors

seems to be implementation detail
2024-03-26 12:11:49 +01:00
Antoine Büsch
4ddc35cdad
Move more dependencies to workspace level (#12270)
# Description
This is a followup to #12043 that moves more dependency versions to
workspace dependencies.

# User-Facing Changes
N/A

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-03-23 18:46:02 -05:00
Devyn Cairns
544e7bcb5e
Make some of the stream tests more robust against bad timeouts (#12271)
# Description

@WindSoilder [reported on
Discord](https://discord.com/channels/601130461678272522/855947301380947968/1221233630093901834)
that some plugin stream tests have been failing on the CI. It seems to
just be a timing thing (probably due to busy CI), so this extends the
amount of time that we can wait for a condition to be true.

# User-Facing Changes
None

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-03-24 07:41:27 +08:00
Devyn Cairns
78be67f0c6
Support for getting help text from a plugin command (#12243)
# Description
There wasn't really a good way to implement a command group style (e.g.
`from`, `query`, etc.) command in the past that just returns the help
text even if `--help` is not passed. This adds a new engine call that
just does that.

This is actually something I ran into before when developing the dbus
plugin, so it's nice to fix it.

# User-Facing Changes


# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [ ] Document `GetHelp` engine call in proto
2024-03-24 07:30:38 +08:00
Devyn Cairns
c79c43d2f8
Add test support crate for plugin developers (#12259)
# Description

Adds a `nu-plugin-test-support` crate with an interface that supports
testing plugins.

Unlike in reality, these plugins run in the same process on separate
threads. This will allow
testing aspects of the plugin internal state and handling serialized
plugin custom values easily.
We still serialize their custom values and all of the engine to plugin
logic is still in play, so
from a logical perspective this should still expose any bugs that would
have been caused by that.
The only difference is that it doesn't run in a different process, and
doesn't try to serialize
everything to the final wire format for stdin/stdout.

TODO still:

- [x] Clean up warnings about private types exposed in trait definition
- [x] Automatically deserialize plugin custom values in the result so
they can be inspected
- [x] Automatic plugin examples test function
- [x] Write a bit more documentation
- [x] More tests
- [x] Add MIT License file to new crate

# User-Facing Changes

Plugin developers get a nice way to test their plugins.

# Tests + Formatting
Run the tests with `cargo test -p nu-plugin-test-support --
--show-output` to see some examples of what the failing test output for
examples can look like. I used the `difference` crate (MIT licensed) to
make it look nice.

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

- [ ] Add a section to the book about testing
- [ ] Test some of the example plugins this way
- [ ] Add example tests to nu_plugin_template so plugin developers have
something to start with
2024-03-23 13:29:54 -05:00
Devyn Cairns
ff41cf91ef
Misc doc fixes (#12266)
# Description

Just a bunch of miscellaneous fixes to the Rust documentation that I
found recently while doing
a pass on some things.

# User-Facing Changes
None
2024-03-23 07:26:08 -05:00
Devyn Cairns
efe25e3f58
Better generic errors for plugins (and perhaps scripts) (#12236)
# Description
This makes `LabeledError` much more capable of representing close to
everything a `miette::Diagnostic` can, including `ShellError`, and
allows plugins to generate multiple error spans, codes, help, etc.

`LabeledError` is now embeddable within `ShellError` as a transparent
variant.

This could also be used to improve `error make` and `try/catch` to
reflect `LabeledError` exactly in the future.

Also cleaned up some errors in existing plugins.

# User-Facing Changes
Breaking change for plugins. Nicer errors for users.
2024-03-21 12:27:21 +01:00
Devyn Cairns
c810f5e3da
Refactor PluginCustomValue::render_to_base_value_in (#12244)
# Description

Changed to use `Value::recurse_mut` like the other functions.

# User-Facing Changes
None

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
2024-03-20 17:22:25 +08:00
Devyn Cairns
dcf2e8ce9a
Refactor PipelineDataHeader ⇄ PipelineData mapping (#12248)
# Description
It was a bit ugly that when new `EngineCall`s or response types were
added, they needed to be added to multiple places with redundant code
just to change the types, even if they didn't have any stream content.

This fixes that and locates all of that logic in one place.

# User-Facing Changes
None

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-03-20 16:57:22 +08:00
Stefan Holderbach
f56070cbcd
Respond to nightly clippy (#12174)
Babe, wake up new nightly clippy just dropped

- Move `catch_unwind` block out of `match` scrutinee
- Remove unused members in `PluginExecutionContext`
2024-03-20 09:46:39 +08:00
Devyn Cairns
02551c416c
Fix broken build: replace value_string() straggler (#12237)
# Description

Fix after #12230 and #12231 crossed wires and broke the build
2024-03-19 07:52:49 -05:00
Devyn Cairns
6795ad7e33
Make custom value type handling more consistent (#12230)
[Context on
Discord](https://discord.com/channels/601130461678272522/855947301380947968/1219425984990806207)

# Description

- Rename `CustomValue::value_string()` to `type_name()` to reflect its
usage better.
- Change print behavior to always call `to_base_value()` first, to give
the custom value better control over the output.
- Change `describe --detailed` to show the type name as the subtype,
rather than trying to describe the base value.
- Change custom `Type` to use `type_name()` rather than `typetag_name()`
to make things like `PluginCustomValue` more transparent

One question: should `describe --detailed` still include a description
of the base value somewhere? I'm torn on it, it seems possibly useful
for some things (maybe sqlite databases?), but having `describe -d` not
include the custom type name anywhere felt weird. Another option would
be to add another method to `CustomValue` for info to be displayed in
`describe`, so that it can be more type-specific?

# User-Facing Changes
Everything above has implications for printing and `describe` on custom
values

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
2024-03-19 11:09:59 +01:00
Devyn Cairns
992359a191
Support for custom values in plugin examples (#12213)
# Description
@ayax79 says that the dataframe commands all have dataframe custom
values in their examples, and they're used for tests.

Rather than send the custom values to the engine, if they're in
examples, this change just renders them using `to_base_value()` first.
That way we avoid potentially having to hold onto custom values in
`plugins.nu` that might not be valid indefinitely - as will be the case
for dataframes in particular - but we still avoid forcing plugin writers
to not use custom values in their examples.

# User-Facing Changes
- Custom values usable in plugin examples

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
2024-03-18 07:34:21 -05:00
Devyn Cairns
1cb5221f01
Add Value::recurse_mut() to save duplicated code in PluginCustomValue (#12218)
# Description

We do a lot of visiting contained values in the serialization / validity
functions within `PluginCustomValue` utils. This adds
`Value::recurse_mut()` which wraps up most of that logic into something
that can be reused.
2024-03-16 15:54:42 +01:00
Devyn Cairns
f6faf73e02
Allow plugins to set environment variables in their caller's scope (#12204)
# Description

Adds the `AddEnvVar` plugin call, which allows plugins to set
environment variables in the caller's scope. This is the first engine
call that mutates the caller's stack, and opens the door to more
operations like this if needed.

This also comes with an extra benefit: in doing this, I needed to
refactor how context was handled, and I was able to avoid cloning
`EngineInterface` / `Stack` / `Call` in most cases that plugin calls are
used. They now only need to be cloned if the plugin call returns a
stream. The performance increase is welcome (5.5x faster on `inc`!):

```nushell
# Before
> timeit { 1..100 | each { |i| $"2.0.($i)" | inc -p } }
405ms 941µs 952ns
# After
> timeit { 1..100 | each { |i| $"2.0.($i)" | inc -p } }
73ms 68µs 749ns
```

# User-Facing Changes
- New engine call: `add_env_var()`
- Performance enhancement for plugin calls

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [x] Document env manipulation in plugins guide
- [x] Document `AddEnvVar` in plugin protocol
2024-03-15 06:45:45 -05:00
Devyn Cairns
9cf2e873b5
Reorganize plugin API around commands (#12170)
[Context on
Discord](https://discord.com/channels/601130461678272522/855947301380947968/1216517833312309419)

# Description
This is a significant breaking change to the plugin API, but one I think
is worthwhile. @ayax79 mentioned on Discord that while trying to start
on a dataframes plugin, he was a little disappointed that more wasn't
provided in terms of code organization for commands, particularly since
there are *a lot* of `dfr` commands.

This change treats plugins more like miniatures of the engine, with
dispatch of the command name being handled inherently, each command
being its own type, and each having their own signature within the trait
impl for the command type rather than having to find a way to centralize
it all into one `Vec`.

For the example plugins that have multiple commands, I definitely like
how this looks a lot better. This encourages doing code organization the
right way and feels very good.

For the plugins that have only one command, it's just a little bit more
boilerplate - but still worth it, in my opinion.

The `Box<dyn PluginCommand<Plugin = Self>>` type in `commands()` is a
little bit hairy, particularly for Rust beginners, but ultimately not so
bad, and it gives the desired flexibility for shared state for a whole
plugin + the individual commands.

# User-Facing Changes
Pretty big breaking change to plugin API, but probably one that's worth
making.

```rust
use nu_plugin::*;
use nu_protocol::{PluginSignature, PipelineData, Type, Value};

struct LowercasePlugin;
struct Lowercase;

// Plugins can now have multiple commands
impl PluginCommand for Lowercase {
    type Plugin = LowercasePlugin;

    // The signature lives with the command
    fn signature(&self) -> PluginSignature {
        PluginSignature::build("lowercase")
            .usage("Convert each string in a stream to lowercase")
            .input_output_type(Type::List(Type::String.into()), Type::List(Type::String.into()))
    }

    // We also provide SimplePluginCommand which operates on Value like before
    fn run(
        &self,
        plugin: &LowercasePlugin,
        engine: &EngineInterface,
        call: &EvaluatedCall,
        input: PipelineData,
    ) -> Result<PipelineData, LabeledError> {
        let span = call.head;
        Ok(input.map(move |value| {
            value.as_str()
                .map(|string| Value::string(string.to_lowercase(), span))
                // Errors in a stream should be returned as values.
                .unwrap_or_else(|err| Value::error(err, span))
        }, None)?)
    }
}

// Plugin now just has a list of commands, and the custom value op stuff still goes here
impl Plugin for LowercasePlugin {
    fn commands(&self) -> Vec<Box<dyn PluginCommand<Plugin=Self>>> {
        vec![Box::new(Lowercase)]
    }
}

fn main() {
    serve_plugin(&LowercasePlugin{}, MsgPackSerializer)
}
```

Time this however you like - we're already breaking stuff for 0.92, so
it might be good to do it now, but if it feels like a lot all at once,
it could wait.

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [ ] Update examples in the book
- [x] Fix #12088 to match - this change would actually simplify it a
lot, because the methods are currently just duplicated between `Plugin`
and `StreamingPlugin`, but they only need to be on `Plugin` with this
change
2024-03-14 16:40:02 -05:00
Ian Manske
b6c7656194
IO and redirection overhaul (#11934)
# Description
The PR overhauls how IO redirection is handled, allowing more explicit
and fine-grain control over `stdout` and `stderr` output as well as more
efficient IO and piping.

To summarize the changes in this PR:
- Added a new `IoStream` type to indicate the intended destination for a
pipeline element's `stdout` and `stderr`.
- The `stdout` and `stderr` `IoStream`s are stored in the `Stack` and to
avoid adding 6 additional arguments to every eval function and
`Command::run`. The `stdout` and `stderr` streams can be temporarily
overwritten through functions on `Stack` and these functions will return
a guard that restores the original `stdout` and `stderr` when dropped.
- In the AST, redirections are now directly part of a `PipelineElement`
as a `Option<Redirection>` field instead of having multiple different
`PipelineElement` enum variants for each kind of redirection. This
required changes to the parser, mainly in `lite_parser.rs`.
- `Command`s can also set a `IoStream` override/redirection which will
apply to the previous command in the pipeline. This is used, for
example, in `ignore` to allow the previous external command to have its
stdout redirected to `Stdio::null()` at spawn time. In contrast, the
current implementation has to create an os pipe and manually consume the
output on nushell's side. File and pipe redirections (`o>`, `e>`, `e>|`,
etc.) have precedence over overrides from commands.

This PR improves piping and IO speed, partially addressing #10763. Using
the `throughput` command from that issue, this PR gives the following
speedup on my setup for the commands below:
| Command | Before (MB/s) | After (MB/s) | Bash (MB/s) |
| --------------------------- | -------------:| ------------:|
-----------:|
| `throughput o> /dev/null` | 1169 | 52938 | 54305 |
| `throughput \| ignore` | 840 | 55438 | N/A |
| `throughput \| null` | Error | 53617 | N/A |
| `throughput \| rg 'x'` | 1165 | 3049 | 3736 |
| `(throughput) \| rg 'x'` | 810 | 3085 | 3815 |

(Numbers above are the median samples for throughput)

This PR also paves the way to refactor our `ExternalStream` handling in
the various commands. For example, this PR already fixes the following
code:
```nushell
^sh -c 'echo -n "hello "; sleep 0; echo "world"' | find "hello world"
```
This returns an empty list on 0.90.1 and returns a highlighted "hello
world" on this PR.

Since the `stdout` and `stderr` `IoStream`s are available to commands
when they are run, then this unlocks the potential for more convenient
behavior. E.g., the `find` command can disable its ansi highlighting if
it detects that the output `IoStream` is not the terminal. Knowing the
output streams will also allow background job output to be redirected
more easily and efficiently.

# User-Facing Changes
- External commands returned from closures will be collected (in most
cases):
  ```nushell
  1..2 | each {|_| nu -c "print a" }
  ```
This gives `["a", "a"]` on this PR, whereas this used to print "a\na\n"
and then return an empty list.

  ```nushell
  1..2 | each {|_| nu -c "print -e a" }
  ```
This gives `["", ""]` and prints "a\na\n" to stderr, whereas this used
to return an empty list and print "a\na\n" to stderr.

- Trailing new lines are always trimmed for external commands when
piping into internal commands or collecting it as a value. (Failure to
decode the output as utf-8 will keep the trailing newline for the last
binary value.) In the current nushell version, the following three code
snippets differ only in parenthesis placement, but they all also have
different outputs:

  1. `1..2 | each { ^echo a }`
     ```
     a
     a
     ╭────────────╮
     │ empty list │
     ╰────────────╯
     ```
  2. `1..2 | each { (^echo a) }`
     ```
     ╭───┬───╮
     │ 0 │ a │
     │ 1 │ a │
     ╰───┴───╯
     ```
  3. `1..2 | (each { ^echo a })`
     ```
     ╭───┬───╮
     │ 0 │ a │
     │   │   │
     │ 1 │ a │
     │   │   │
     ╰───┴───╯
     ```

  But in this PR, the above snippets will all have the same output:
  ```
  ╭───┬───╮
  │ 0 │ a │
  │ 1 │ a │
  ╰───┴───╯
  ```

- All existing flags on `run-external` are now deprecated.

- File redirections now apply to all commands inside a code block:
  ```nushell
  (nu -c "print -e a"; nu -c "print -e b") e> test.out
  ```
This gives "a\nb\n" in `test.out` and prints nothing. The same result
would happen when printing to stdout and using a `o>` file redirection.

- External command output will (almost) never be ignored, and ignoring
output must be explicit now:
  ```nushell
  (^echo a; ^echo b)
  ```
This prints "a\nb\n", whereas this used to print only "b\n". This only
applies to external commands; values and internal commands not in return
position will not print anything (e.g., `(echo a; echo b)` still only
prints "b").

- `complete` now always captures stderr (`do` is not necessary).

# After Submitting
The language guide and other documentation will need to be updated.
2024-03-14 15:51:55 -05:00
Wind
e2907e7e3a
remove test warnings (#12201)
# Description
I get warnings message when running tests:
```
warning: unused import: `Feature`
  --> crates/nu-plugin/src/protocol/mod.rs:21:25
   |
21 | pub use protocol_info::{Feature, Protocol};
   |                         ^^^^^^^
   |
   = note: `#[warn(unused_imports)]` on by default
```
I think it's useless can can be removed.
2024-03-14 22:34:00 +08:00
Devyn Cairns
ad2fd520ca
MsgPack deserializer: improve handling of EOF (#12183)
# Description

`rmp_serde` has two kinds of errors that contain I/O errors, and an EOF
can occur inside either of them, but we were only treating an EOF inside
an `InvalidMarkerRead` as an EOF, which would make sense for the
beginning of a message.

However, we should also treat an incomplete message + EOF as an EOF.
There isn't really any point in reporting that an EOF was received
mid-message.

This should fix the issue where the
`seq_describe_no_collect_succeeds_without_error` test would sometimes
fail, as doing a `describe --no-collect` followed by nushell exiting
could (but was not guaranteed to) cause this exact scenario.

# User-Facing Changes
Will probably remove useless `read error` messages from plugins after
exit of `nu`

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
2024-03-13 06:49:53 -05:00
Devyn Cairns
e1cfc96ee8
Fix locking soundness in PersistentPlugin (#12182)
# Description

There were two problems in `PersistentPlugin` which could cause a
deadlock:

1. There were two mutexes being used, and `get()` could potentially hold
both simultaneously if it had to spawn. This won't necessarily cause a
deadlock on its own, but it does mean that lock order is sensitive

2. `set_gc_config()` called `flush()` while still holding the lock,
meaning that the GC thread had to proceed before the lock was released.
However, waiting for the GC thread to proceed could mean waiting for the
GC thread to call `stop()`, which itself would try to lock the mutex.
So, it's not safe to wait for the GC thread while the lock is held. This
is fixed now.

I've also reverted #12177, as @IanManske reported that this was also
happening for him on Linux, and it seems to be this problem which should
not be platform-specific at all. I believe this solves it.

# User-Facing Changes
None

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
2024-03-12 18:22:29 -05:00
Devyn Cairns
390a7e3f0b
Add environment engine calls for plugins (#12166)
# Description

This adds three engine calls: `GetEnvVar`, `GetEnvVars`, for getting
environment variables from the plugin command context, and
`GetCurrentDir` for getting the current working directory.

Plugins are now launched in the directory of their executable to try to
make improper use of the current directory without first setting it more
obvious. Plugins previously launched in whatever the current directory
of the engine was at the time the plugin command was run, but switching
to persistent plugins broke this, because they stay in whatever
directory they launched in initially.

This also fixes the `gstat` plugin to use `get_current_dir()` to
determine its repo location, which was directly affected by this
problem.

# User-Facing Changes
- Adds new engine calls (`GetEnvVar`, `GetEnvVars`, `GetCurrentDir`)
- Runs plugins in a different directory from before, in order to catch
bugs
- Plugins will have to use the new engine calls if they do filesystem
stuff to work properly

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [ ] Document the working directory behavior on plugin launch
- [ ] Document the new engine calls + response type (`ValueMap`)
2024-03-12 06:34:32 -05:00
Devyn Cairns
37a9f21b2a
Sync with the plugin garbage collector when setting config (#12152)
# Description
This causes `PersistentPlugin` to wait for the plugin garbage collector
to actually receive and process its config when setting it in
`set_gc_config`.

The motivation behind doing this is to make setting GC config in scripts
more deterministic. Before this change we couldn't really guarantee that
the GC could see your config before you started doing other things.

There is a slight cost to performance to doing this - we set config
before each plugin call because we don't necessarily know that it
reflects what's in `$env.config`, and now to do that we have to
synchronize with the GC thread.

This was probably the cause of spuriously failing tests as mentioned by
@sholderbach. Hopefully this fixes it. It might be the case that
launching threads on some platforms (or just on a really busy test
runner) sometimes takes a significant amount of time.

# User-Facing Changes
- possibly slightly worse performance for plugin calls
2024-03-12 10:50:13 +01:00
Devyn Cairns
73f3c0b60b
Support for all custom value operations on plugin custom values (#12088)
# Description

Adds support for the following operations on plugin custom values, in
addition to `to_base_value` which was already present:

- `follow_path_int()`
- `follow_path_string()`
- `partial_cmp()`
- `operation()`
- `Drop` (notification, if opted into with
`CustomValue::notify_plugin_on_drop`)

There are additionally customizable methods within the `Plugin` and
`StreamingPlugin` traits for implementing these functions in a way that
requires access to the plugin state, as a registered handle model such
as might be used in a dataframes plugin would.

`Value::append` was also changed to handle custom values correctly.

# User-Facing Changes

- Signature of `CustomValue::follow_path_string` and
`CustomValue::follow_path_int` changed to give access to the span of the
custom value itself, useful for some errors.
- Plugins using custom values have to be recompiled because the engine
will try to do custom value operations that aren't supported
- Plugins can do more things 🎉 

# Tests + Formatting
Tests were added for all of the new custom values functionality.

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
- [ ] Document protocol reference `CustomValueOp` variants:
  - [ ] `FollowPathInt`
  - [ ] `FollowPathString`
  - [ ] `PartialCmp`
  - [ ] `Operation`
  - [ ] `Dropped`
- [ ] Document `notify_on_drop` optional field in `PluginCustomValue`
2024-03-12 10:37:08 +01:00
Devyn Cairns
bc19be25b1
Keep plugins persistently running in the background (#12064)
# Description
This PR uses the new plugin protocol to intelligently keep plugin
processes running in the background for further plugin calls.

Running plugins can be seen by running the new `plugin list` command,
and stopped by running the new `plugin stop` command.

This is an enhancement for the performance of plugins, as starting new
plugin processes has overhead, especially for plugins in languages that
take a significant amount of time on startup. It also enables plugins
that have persistent state between commands, making the migration of
features like dataframes and `stor` to plugins possible.

Plugins are automatically stopped by the new plugin garbage collector,
configurable with `$env.config.plugin_gc`:

```nushell
  $env.config.plugin_gc = {
      # Configuration for plugin garbage collection
      default: {
          enabled: true # true to enable stopping of inactive plugins
          stop_after: 10sec # how long to wait after a plugin is inactive to stop it
      }
      plugins: {
          # alternate configuration for specific plugins, by name, for example:
          #
          # gstat: {
          #     enabled: false
          # }
      }
  }
```

If garbage collection is enabled, plugins will be stopped after
`stop_after` passes after they were last active. Plugins are counted as
inactive if they have no running plugin calls. Reading the stream from
the response of a plugin call is still considered to be activity, but if
a plugin holds on to a stream but the call ends without an active
streaming response, it is not counted as active even if it is reading
it. Plugins can explicitly disable the GC as appropriate with
`engine.set_gc_disabled(true)`.

The `version` command now lists plugin names rather than plugin
commands. The list of plugin commands is accessible via `plugin list`.

Recommend doing this together with #12029, because it will likely force
plugin developers to do the right thing with mutability and lead to less
unexpected behavior when running plugins nested / in parallel.

# User-Facing Changes
- new command: `plugin list`
- new command: `plugin stop`
- changed command: `version` (now lists plugin names, rather than
commands)
- new config: `$env.config.plugin_gc`
- Plugins will keep running and be reused, at least for the configured
GC period
- Plugins that used mutable state in weird ways like `inc` did might
misbehave until fixed
- Plugins can disable GC if they need to
- Had to change plugin signature to accept `&EngineInterface` so that
the GC disable feature works. #12029 does this anyway, and I'm expecting
(resolvable) conflicts with that

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

Because there is some specific OS behavior required for plugins to not
respond to Ctrl-C directly, I've developed against and tested on both
Linux and Windows to ensure that works properly.

# After Submitting
I think this probably needs to be in the book somewhere
2024-03-09 17:10:22 -06:00
Devyn Cairns
430fb1fcb6
Add support for engine calls from plugins (#12029)
# Description

This allows plugins to make calls back to the engine to get config,
evaluate closures, and do other things that must be done within the
engine process.

Engine calls can both produce and consume streams as necessary. Closures
passed to plugins can both accept stream input and produce stream output
sent back to the plugin.

Engine calls referring to a plugin call's context can be processed as
long either the response hasn't been received, or the response created
streams that haven't ended yet.

This is a breaking API change for plugins. There are some pretty major
changes to the interface that plugins must implement, including:

1. Plugins now run with `&self` and must be `Sync`. Executing multiple
plugin calls in parallel is supported, and there's a chance that a
closure passed to a plugin could invoke the same plugin. Supporting
state across plugin invocations is left up to the plugin author to do in
whichever way they feel best, but the plugin object itself is still
shared. Even though the engine doesn't run multiple plugin calls through
the same process yet, I still considered it important to break the API
in this way at this stage. We might want to consider an optional
threadpool feature for performance.

2. Plugins take a reference to `EngineInterface`, which can be cloned.
This interface allows plugins to make calls back to the engine,
including for getting config and running closures.

3. Plugins no longer take the `config` parameter. This can be accessed
from the interface via the `.get_plugin_config()` engine call.


# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
Not only does this have plugin protocol changes, it will require plugins
to make some code changes before they will work again. But on the plus
side, the engine call feature is extensible, and we can add more things
to it as needed.

Plugin maintainers will have to change the trait signature at the very
least. If they were using `config`, they will have to call
`engine.get_plugin_config()` instead.

If they were using the mutable reference to the plugin, they will have
to come up with some strategy to work around it (for example, for `Inc`
I just cloned it). This shouldn't be such a big deal at the moment as
it's not like plugins have ever run as daemons with persistent state in
the past, and they don't in this PR either. But I thought it was
important to make the change before we support plugins as daemons, as an
exclusive mutable reference is not compatible with parallel plugin
calls.

I suggest this gets merged sometime *after* the current pending release,
so that we have some time to adjust to the previous plugin protocol
changes that don't require code changes before making ones that do.

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`


# After Submitting
I will document the additional protocol features (`EngineCall`,
`EngineCallResponse`), and constraints on plugin call processing if
engine calls are used - basically, to be aware that an engine call could
result in a nested plugin call, so the plugin should be able to handle
that.
2024-03-09 11:26:30 -06:00