use nu_protocol::{
ast::Call,
engine::{Command, EngineState, Stack},
Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Type, Value,
};
use super::utils;
#[derive(Clone)]
pub struct All;
impl Command for All {
fn name(&self) -> &str {
"all"
}
fn signature(&self) -> Signature {
Signature::build(self.name())
.input_output_types(vec![(Type::List(Box::new(Type::Any)), Type::Bool)])
.required(
"predicate",
SyntaxShape::Closure(Some(vec![SyntaxShape::Any, SyntaxShape::Int])),
"A closure that must evaluate to a boolean.",
)
.category(Category::Filters)
}
fn usage(&self) -> &str {
"Test if every element of the input fulfills a predicate expression."
}
fn search_terms(&self) -> Vec<&str> {
vec!["every", "and"]
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Check if each row's status is the string 'UP'",
example: "[[status]; [UP] [UP]] | all {|el| $el.status == UP }",
result: Some(Value::test_bool(true)),
},
Example {
description: "Check that each item is a string",
example: "[foo bar 2 baz] | all {|| ($in | describe) == 'string' }",
result: Some(Value::test_bool(false)),
},
Example {
description: "Check that all values are equal to twice their index",
example: "[0 2 4 6] | enumerate | all {|i| $i.item == $i.index * 2 }",
result: Some(Value::test_bool(true)),
},
Example {
description: "Check that all of the values are even, using a stored closure",
example: "let cond = {|el| ($el mod 2) == 0 }; [2 4 6 8] | all $cond",
result: Some(Value::test_bool(true)),
},
]
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
utils::boolean_fold(engine_state, stack, call, input, false)
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_examples() {
use crate::test_examples;
test_examples(All)
}
}