Replace ExternalStream with new ByteStream type (#12774)

# Description
This PR introduces a `ByteStream` type which is a `Read`-able stream of
bytes. Internally, it has an enum over three different byte stream
sources:
```rust
pub enum ByteStreamSource {
    Read(Box<dyn Read + Send + 'static>),
    File(File),
    Child(ChildProcess),
}
```

This is in comparison to the current `RawStream` type, which is an
`Iterator<Item = Vec<u8>>` and has to allocate for each read chunk.

Currently, `PipelineData::ExternalStream` serves a weird dual role where
it is either external command output or a wrapper around `RawStream`.
`ByteStream` makes this distinction more clear (via `ByteStreamSource`)
and replaces `PipelineData::ExternalStream` in this PR:
```rust
pub enum PipelineData {
    Empty,
    Value(Value, Option<PipelineMetadata>),
    ListStream(ListStream, Option<PipelineMetadata>),
    ByteStream(ByteStream, Option<PipelineMetadata>),
}
```

The PR is relatively large, but a decent amount of it is just repetitive
changes.

This PR fixes #7017, fixes #10763, and fixes #12369.

This PR also improves performance when piping external commands. Nushell
should, in most cases, have competitive pipeline throughput compared to,
e.g., bash.
| Command | Before (MB/s) | After (MB/s) | Bash (MB/s) |
| -------------------------------------------------- | -------------:|
------------:| -----------:|
| `throughput \| rg 'x'` | 3059 | 3744 | 3739 |
| `throughput \| nu --testbin relay o> /dev/null` | 3508 | 8087 | 8136 |

# User-Facing Changes
- This is a breaking change for the plugin communication protocol,
because the `ExternalStreamInfo` was replaced with `ByteStreamInfo`.
Plugins now only have to deal with a single input stream, as opposed to
the previous three streams: stdout, stderr, and exit code.
- The output of `describe` has been changed for external/byte streams.
- Temporary breaking change: `bytes starts-with` no longer works with
byte streams. This is to keep the PR smaller, and `bytes ends-with`
already does not work on byte streams.
- If a process core dumped, then instead of having a `Value::Error` in
the `exit_code` column of the output returned from `complete`, it now is
a `Value::Int` with the negation of the signal number.

# After Submitting
- Update docs and book as necessary
- Release notes (e.g., plugin protocol changes)
- Adapt/convert commands to work with byte streams (high priority is
`str length`, `bytes starts-with`, and maybe `bytes ends-with`).
- Refactor the `tee` code, Devyn has already done some work on this.

---------

Co-authored-by: Devyn Cairns <devyn.cairns@gmail.com>
This commit is contained in:
Ian Manske
2024-05-16 14:11:18 +00:00
committed by GitHub
parent 1b8eb23785
commit 6fd854ed9f
210 changed files with 3955 additions and 4012 deletions

View File

@ -82,7 +82,7 @@
//! let input = vec![Value::test_string("FooBar")].into_pipeline_data(Span::test_data(), None);
//! let output = PluginTest::new("lowercase", LowercasePlugin.into())?
//! .eval_with("lowercase", input)?
//! .into_value(Span::test_data());
//! .into_value(Span::test_data())?;
//!
//! assert_eq!(
//! Value::test_list(vec![

View File

@ -93,7 +93,7 @@ impl PluginTest {
/// "my-command",
/// vec![Value::test_int(42)].into_pipeline_data(Span::test_data(), None)
/// )?
/// .into_value(Span::test_data());
/// .into_value(Span::test_data())?;
/// assert_eq!(Value::test_string("42"), result);
/// # Ok(())
/// # }
@ -136,33 +136,44 @@ impl PluginTest {
// Serialize custom values in the input
let source = self.source.clone();
let input = input.map(
move |mut value| {
let result = PluginCustomValue::serialize_custom_values_in(&mut value)
// Make sure to mark them with the source so they pass correctly, too.
.and_then(|_| PluginCustomValueWithSource::add_source_in(&mut value, &source));
match result {
Ok(()) => value,
Err(err) => Value::error(err, value.span()),
}
},
None,
)?;
let input = if matches!(input, PipelineData::ByteStream(..)) {
input
} else {
input.map(
move |mut value| {
let result = PluginCustomValue::serialize_custom_values_in(&mut value)
// Make sure to mark them with the source so they pass correctly, too.
.and_then(|_| {
PluginCustomValueWithSource::add_source_in(&mut value, &source)
});
match result {
Ok(()) => value,
Err(err) => Value::error(err, value.span()),
}
},
None,
)?
};
// Eval the block with the input
let mut stack = Stack::new().capture();
eval_block::<WithoutDebug>(&self.engine_state, &mut stack, &block, input)?.map(
|mut value| {
// Make sure to deserialize custom values
let result = PluginCustomValueWithSource::remove_source_in(&mut value)
.and_then(|_| PluginCustomValue::deserialize_custom_values_in(&mut value));
match result {
Ok(()) => value,
Err(err) => Value::error(err, value.span()),
}
},
None,
)
let data = eval_block::<WithoutDebug>(&self.engine_state, &mut stack, &block, input)?;
if matches!(data, PipelineData::ByteStream(..)) {
Ok(data)
} else {
data.map(
|mut value| {
// Make sure to deserialize custom values
let result = PluginCustomValueWithSource::remove_source_in(&mut value)
.and_then(|_| PluginCustomValue::deserialize_custom_values_in(&mut value));
match result {
Ok(()) => value,
Err(err) => Value::error(err, value.span()),
}
},
None,
)
}
}
/// Evaluate some Nushell source code with the plugin commands in scope.
@ -176,7 +187,7 @@ impl PluginTest {
/// # fn test(MyPlugin: impl Plugin + Send + 'static) -> Result<(), ShellError> {
/// let result = PluginTest::new("my_plugin", MyPlugin.into())?
/// .eval("42 | my-command")?
/// .into_value(Span::test_data());
/// .into_value(Span::test_data())?;
/// assert_eq!(Value::test_string("42"), result);
/// # Ok(())
/// # }
@ -219,7 +230,7 @@ impl PluginTest {
if let Some(expectation) = &example.result {
match self.eval(example.example) {
Ok(data) => {
let mut value = data.into_value(Span::test_data());
let mut value = data.into_value(Span::test_data())?;
// Set all of the spans in the value to test_data() to avoid unnecessary
// differences when printing

View File

@ -143,7 +143,7 @@ fn test_into_int_from_u32() -> Result<(), ShellError> {
"into int from u32",
PipelineData::Value(CustomU32(42).into_value(Span::test_data()), None),
)?
.into_value(Span::test_data());
.into_value(Span::test_data())?;
assert_eq!(Value::test_int(42), result);
Ok(())
}

View File

@ -80,7 +80,7 @@ fn test_requiring_nu_cmd_lang_commands() -> Result<(), ShellError> {
let result = PluginTest::new("hello", HelloPlugin.into())?
.eval("do { let greeting = hello; $greeting }")?
.into_value(Span::test_data());
.into_value(Span::test_data())?;
assert_eq!(Value::test_string("Hello, World!"), result);

View File

@ -73,7 +73,7 @@ fn test_lowercase_using_eval_with() -> Result<(), ShellError> {
assert_eq!(
Value::test_list(vec![Value::test_string("hello world")]),
result.into_value(Span::test_data())
result.into_value(Span::test_data())?
);
Ok(())