nushell/crates/nu-command/src/math/ln.rs
Jérémy Audiger 99076af18b
Use imported names in Command::run signatures (#7967)
# Description

_(Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.)_

I opened this PR to unify the run command method. It's mainly to improve
consistency across the tree.

# User-Facing Changes

None.

# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass

# After Submitting

If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
2023-02-05 22:17:46 +01:00

102 lines
2.7 KiB
Rust

use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Type, Value};
#[derive(Clone)]
pub struct SubCommand;
impl Command for SubCommand {
fn name(&self) -> &str {
"math ln"
}
fn signature(&self) -> Signature {
Signature::build("math ln")
.input_output_types(vec![(Type::Number, Type::Float)])
.vectorizes_over_list(true)
.category(Category::Math)
}
fn usage(&self) -> &str {
"Returns the natural logarithm. Base: (math e)"
}
fn search_terms(&self) -> Vec<&str> {
vec!["natural", "logarithm", "inverse", "euler"]
}
fn run(
&self,
engine_state: &EngineState,
_stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let head = call.head;
// This doesn't match explicit nulls
if matches!(input, PipelineData::Empty) {
return Err(ShellError::PipelineEmpty(head));
}
input.map(
move |value| operate(value, head),
engine_state.ctrlc.clone(),
)
}
fn examples(&self) -> Vec<Example> {
vec![Example {
description: "Get the natural logarithm of e",
example: "math e | math ln",
result: Some(Value::test_float(1.0f64)),
}]
}
}
fn operate(value: Value, head: Span) -> Value {
match value {
numeric @ (Value::Int { .. } | Value::Float { .. }) => {
let (val, span) = match numeric {
Value::Int { val, span } => (val as f64, span),
Value::Float { val, span } => (val, span),
_ => unreachable!(),
};
if val > 0.0 {
let val = val.ln();
Value::Float { val, span }
} else {
Value::Error {
error: ShellError::UnsupportedInput(
"'ln' undefined for values outside the open interval (0, Inf).".into(),
"value originates from here".into(),
head,
span,
),
}
}
}
Value::Error { .. } => value,
other => Value::Error {
error: ShellError::OnlySupportsThisInputType(
"numeric".into(),
other.get_type().to_string(),
head,
other.expect_span(),
),
},
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn test_examples() {
use crate::test_examples;
test_examples(SubCommand {})
}
}