forked from extern/nushell
c747ec75c9
# 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.
110 lines
3.0 KiB
Rust
110 lines
3.0 KiB
Rust
use nu_engine::command_prelude::*;
|
|
|
|
use std::{
|
|
thread,
|
|
time::{Duration, Instant},
|
|
};
|
|
|
|
const CTRL_C_CHECK_INTERVAL: Duration = Duration::from_millis(100);
|
|
|
|
#[derive(Clone)]
|
|
pub struct Sleep;
|
|
|
|
impl Command for Sleep {
|
|
fn name(&self) -> &str {
|
|
"sleep"
|
|
}
|
|
|
|
fn usage(&self) -> &str {
|
|
"Delay for a specified amount of time."
|
|
}
|
|
|
|
fn signature(&self) -> Signature {
|
|
Signature::build("sleep")
|
|
.input_output_types(vec![(Type::Nothing, Type::Nothing)])
|
|
.required("duration", SyntaxShape::Duration, "Time to sleep.")
|
|
.rest("rest", SyntaxShape::Duration, "Additional time.")
|
|
.category(Category::Platform)
|
|
}
|
|
|
|
fn search_terms(&self) -> Vec<&str> {
|
|
vec!["delay", "wait", "timer"]
|
|
}
|
|
|
|
fn run(
|
|
&self,
|
|
engine_state: &EngineState,
|
|
stack: &mut Stack,
|
|
call: &Call,
|
|
_input: PipelineData,
|
|
) -> Result<PipelineData, ShellError> {
|
|
fn duration_from_i64(val: i64) -> Duration {
|
|
Duration::from_nanos(if val < 0 { 0 } else { val as u64 })
|
|
}
|
|
|
|
let duration: i64 = call.req(engine_state, stack, 0)?;
|
|
let rest: Vec<i64> = call.rest(engine_state, stack, 1)?;
|
|
|
|
let total_dur =
|
|
duration_from_i64(duration) + rest.into_iter().map(duration_from_i64).sum::<Duration>();
|
|
let deadline = Instant::now() + total_dur;
|
|
|
|
loop {
|
|
// sleep for 100ms, or until the deadline
|
|
let time_until_deadline = deadline.saturating_duration_since(Instant::now());
|
|
if time_until_deadline.is_zero() {
|
|
break;
|
|
}
|
|
thread::sleep(CTRL_C_CHECK_INTERVAL.min(time_until_deadline));
|
|
// exit early if Ctrl+C was pressed
|
|
if nu_utils::ctrl_c::was_pressed(&engine_state.ctrlc) {
|
|
return Err(ShellError::InterruptedByUser {
|
|
span: Some(call.head),
|
|
});
|
|
}
|
|
}
|
|
|
|
Ok(Value::nothing(call.head).into_pipeline_data())
|
|
}
|
|
|
|
fn examples(&self) -> Vec<Example> {
|
|
vec![
|
|
Example {
|
|
description: "Sleep for 1sec",
|
|
example: "sleep 1sec",
|
|
result: Some(Value::nothing(Span::test_data())),
|
|
},
|
|
Example {
|
|
description: "Sleep for 3sec",
|
|
example: "sleep 1sec 1sec 1sec",
|
|
result: None,
|
|
},
|
|
Example {
|
|
description: "Send output after 1sec",
|
|
example: "sleep 1sec; echo done",
|
|
result: None,
|
|
},
|
|
]
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::Sleep;
|
|
|
|
#[test]
|
|
fn examples_work_as_expected() {
|
|
use crate::test_examples;
|
|
use std::time::Instant;
|
|
|
|
let start = Instant::now();
|
|
test_examples(Sleep {});
|
|
|
|
let elapsed = start.elapsed();
|
|
|
|
// only examples with actual output are run
|
|
assert!(elapsed >= std::time::Duration::from_secs(1));
|
|
assert!(elapsed < std::time::Duration::from_secs(2));
|
|
}
|
|
}
|