nushell/tests/plugins/stream.rs
Ian Manske 6fd854ed9f
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>
2024-05-16 07:11:18 -07:00

208 lines
5.4 KiB
Rust

use rstest::rstest;
use nu_test_support::nu_with_plugins;
use pretty_assertions::assert_eq;
#[test]
fn seq_produces_stream() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"example seq 1 5 | describe"
);
assert_eq!(actual.out, "list<int> (stream)");
}
#[test]
fn seq_describe_no_collect_succeeds_without_error() {
// This tests to ensure that there's no error if the stream is suddenly closed
// Test several times, because this can cause different errors depending on what is written
// when the engine stops running, especially if there's partial output
for _ in 0..10 {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"example seq 1 5 | describe --no-collect"
);
assert_eq!(actual.out, "stream");
assert_eq!(actual.err, "");
}
}
#[test]
fn seq_stream_collects_to_correct_list() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"example seq 1 5 | to json --raw"
);
assert_eq!(actual.out, "[1,2,3,4,5]");
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"example seq 1 0 | to json --raw"
);
assert_eq!(actual.out, "[]");
}
#[test]
fn seq_big_stream() {
// Testing big streams helps to ensure there are no deadlocking bugs
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"example seq 1 100000 | length"
);
assert_eq!(actual.out, "100000");
}
#[test]
fn sum_accepts_list_of_int() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"[1 2 3] | example sum"
);
assert_eq!(actual.out, "6");
}
#[test]
fn sum_accepts_list_of_float() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"[1.0 2.0 3.5] | example sum"
);
assert_eq!(actual.out, "6.5");
}
#[test]
fn sum_accepts_stream_of_int() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"seq 1 5 | example sum"
);
assert_eq!(actual.out, "15");
}
#[test]
fn sum_accepts_stream_of_float() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"seq 1 5 | into float | example sum"
);
assert_eq!(actual.out, "15");
}
#[test]
fn sum_big_stream() {
// Testing big streams helps to ensure there are no deadlocking bugs
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"seq 1 100000 | example sum"
);
assert_eq!(actual.out, "5000050000");
}
#[test]
fn collect_bytes_accepts_list_of_string() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"[a b] | example collect-bytes"
);
assert_eq!(actual.out, "ab");
}
#[test]
fn collect_bytes_accepts_list_of_binary() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"[0x[41] 0x[42]] | example collect-bytes"
);
assert_eq!(actual.out, "AB");
}
#[test]
fn collect_bytes_produces_byte_stream() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"[a b c] | example collect-bytes | describe"
);
assert_eq!(actual.out, "byte stream");
}
#[test]
fn collect_bytes_big_stream() {
// This in particular helps to ensure that a big stream can be both read and written at the same
// time without deadlocking
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
r#"(
seq 1 10000 |
each {|i| ($i | into string) ++ (char newline) } |
example collect-bytes |
lines |
length
)"#
);
assert_eq!(actual.out, "10000");
}
#[test]
fn for_each_prints_on_stderr() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"[a b c] | example for-each { $in }"
);
assert_eq!(actual.err, "a\nb\nc\n");
}
#[test]
fn generate_sequence() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
"example generate 0 { |i| if $i <= 10 { {out: $i, next: ($i + 2)} } } | to json --raw"
);
assert_eq!(actual.out, "[0,2,4,6,8,10]");
}
#[rstest]
#[timeout(std::time::Duration::from_secs(6))]
fn echo_interactivity_on_slow_pipelines() {
// This test works by putting 0 on the upstream immediately, followed by 1 after 10 seconds.
// If values aren't streamed to the plugin as they become available, `example echo` won't emit
// anything until both 0 and 1 are available. The desired behavior is that `example echo` gets
// the 0 immediately, which is consumed by `first`, allowing the pipeline to terminate early.
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_example"),
r#"[1] | each { |n| sleep 10sec; $n } | prepend 0 | example echo | first"#
);
assert_eq!(actual.out, "0");
}