nushell/crates/nu-cli/src/commands/describe.rs

62 lines
1.3 KiB
Rust

use crate::commands::WholeStreamCommand;
use crate::prelude::*;
use nu_errors::ShellError;
use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
pub struct Describe;
#[derive(Deserialize)]
pub struct DescribeArgs {}
#[async_trait]
impl WholeStreamCommand for Describe {
fn name(&self) -> &str {
"describe"
}
fn signature(&self) -> Signature {
Signature::build("describe")
}
fn usage(&self) -> &str {
"Describes the objects in the stream."
}
async fn run(
&self,
args: CommandArgs,
registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
describe(args, registry).await
}
}
pub async fn describe(
args: CommandArgs,
_registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
Ok(args
.input
.map(|row| {
let name = value::format_type(&row, 100);
ReturnSuccess::value(
UntaggedValue::string(name).into_value(Tag::unknown_anchor(row.tag.span)),
)
})
.to_output_stream())
}
#[cfg(test)]
mod tests {
use super::Describe;
use super::ShellError;
#[test]
fn examples_work_as_expected() -> Result<(), ShellError> {
use crate::examples::test as test_examples;
Ok(test_examples(Describe {})?)
}
}