nushell/crates/nu-command/src/commands/reverse.rs
Michael Angerman d06f457b2a
nu-cli refactor moving commands into their own crate nu-command (#2910)
* move commands, futures.rs, script.rs, utils

* move over maybe_print_errors

* add nu_command crate references to nu_cli

* in commands.rs open up to pub mod from pub(crate)

* nu-cli, nu-command, and nu tests are now passing

* cargo fmt

* clean up nu-cli/src/prelude.rs

* code cleanup

* for some reason lex.rs was not formatted, may be causing my error

* remove mod completion from lib.rs which was not being used along with quickcheck macros

* add in allow unused imports

* comment out one failing external test; comment out one failing internal test

* revert commenting out failing tests; something else might be going on; someone with a windows machine should check and see what is going on with these failing windows tests

* Update Cargo.toml

Extend the optional features to nu-command

Co-authored-by: Jonathan Turner <jonathandturner@users.noreply.github.com>
2021-01-12 17:59:53 +13:00

61 lines
1.6 KiB
Rust

use crate::prelude::*;
use nu_engine::WholeStreamCommand;
use nu_errors::ShellError;
use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
pub struct Reverse;
#[async_trait]
impl WholeStreamCommand for Reverse {
fn name(&self) -> &str {
"reverse"
}
fn signature(&self) -> Signature {
Signature::build("reverse")
}
fn usage(&self) -> &str {
"Reverses the table."
}
async fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
reverse(args).await
}
fn examples(&self) -> Vec<Example> {
vec![Example {
description: "Sort list of numbers in descending file size",
example: "echo [3 1 2 19 0] | reverse",
result: Some(vec![
UntaggedValue::int(0).into(),
UntaggedValue::int(19).into(),
UntaggedValue::int(2).into(),
UntaggedValue::int(1).into(),
UntaggedValue::int(3).into(),
]),
}]
}
}
async fn reverse(args: CommandArgs) -> Result<OutputStream, ShellError> {
let args = args.evaluate_once().await?;
let (input, _args) = args.parts();
let input = input.collect::<Vec<_>>().await;
Ok(futures::stream::iter(input.into_iter().rev().map(ReturnSuccess::value)).to_output_stream())
}
#[cfg(test)]
mod tests {
use super::Reverse;
use super::ShellError;
#[test]
fn examples_work_as_expected() -> Result<(), ShellError> {
use crate::examples::test as test_examples;
Ok(test_examples(Reverse {})?)
}
}