nushell/crates/nu-cli/src/commands/reject.rs
2020-05-29 20:22:52 +12:00

81 lines
2.0 KiB
Rust

use crate::commands::WholeStreamCommand;
use crate::data::base::reject_fields;
use crate::prelude::*;
use nu_errors::ShellError;
use nu_protocol::{ReturnSuccess, Signature, SyntaxShape};
use nu_source::Tagged;
#[derive(Deserialize)]
pub struct RejectArgs {
rest: Vec<Tagged<String>>,
}
pub struct Reject;
#[async_trait]
impl WholeStreamCommand for Reject {
fn name(&self) -> &str {
"reject"
}
fn signature(&self) -> Signature {
Signature::build("reject").rest(SyntaxShape::String, "the names of columns to remove")
}
fn usage(&self) -> &str {
"Remove the given columns from the table."
}
async fn run(
&self,
args: CommandArgs,
registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
reject(args, registry)
}
fn examples(&self) -> Vec<Example> {
vec![Example {
description: "Lists the files in a directory without showing the modified column",
example: "ls | reject modified",
result: None,
}]
}
}
fn reject(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
let registry = registry.clone();
let stream = async_stream! {
let name = args.call_info.name_tag.clone();
let (RejectArgs { rest: fields }, mut input) = args.process(&registry).await?;
if fields.is_empty() {
yield Err(ShellError::labeled_error(
"Reject requires fields",
"needs parameter",
name,
));
return;
}
let fields: Vec<_> = fields.iter().map(|f| f.item.clone()).collect();
while let Some(item) = input.next().await {
yield ReturnSuccess::value(reject_fields(&item, &fields, &item.tag));
}
};
Ok(stream.to_output_stream())
}
#[cfg(test)]
mod tests {
use super::Reject;
#[test]
fn examples_work_as_expected() {
use crate::examples::test as test_examples;
test_examples(Reject {})
}
}