# 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`
# 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.
# 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
# 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.
