use crate::dataframe::values::NuExpression;
use nu_engine::command_prelude::*;
#[derive(Clone)]
pub struct ExprLit;
impl Command for ExprLit {
fn name(&self) -> &str {
"dfr lit"
}
fn usage(&self) -> &str {
"Creates a literal expression."
}
fn signature(&self) -> Signature {
Signature::build(self.name())
.required(
"literal",
SyntaxShape::Any,
"literal to construct the expression",
)
.input_output_type(Type::Any, Type::Custom("expression".into()))
.category(Category::Custom("expression".into()))
}
fn examples(&self) -> Vec<Example> {
vec![Example {
description: "Created a literal expression and converts it to a nu object",
example: "dfr lit 2 | dfr into-nu",
result: Some(Value::test_record(record! {
"expr" => Value::test_string("literal"),
"value" => Value::test_string("2"),
})),
}]
}
fn search_terms(&self) -> Vec<&str> {
vec!["string", "literal", "expression"]
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
_input: PipelineData,
) -> Result<PipelineData, ShellError> {
let literal: Value = call.req(engine_state, stack, 0)?;
let expr = NuExpression::try_from_value(literal)?;
Ok(PipelineData::Value(
NuExpression::into_value(expr, call.head),
None,
))
}
}
#[cfg(test)]
mod test {
use super::super::super::test_dataframe::test_dataframe;
use super::*;
use crate::dataframe::eager::ToNu;
#[test]
fn test_examples() {
test_dataframe(vec![Box::new(ExprLit {}), Box::new(ToNu {})])
}
}