nu_command/random/
float.rs

1use nu_engine::command_prelude::*;
2use nu_protocol::{FloatRange, Range};
3use rand::random_range;
4use std::ops::Bound;
5
6#[derive(Clone)]
7pub struct RandomFloat;
8
9impl Command for RandomFloat {
10    fn name(&self) -> &str {
11        "random float"
12    }
13
14    fn signature(&self) -> Signature {
15        Signature::build("random float")
16            .input_output_types(vec![(Type::Nothing, Type::Float)])
17            .allow_variants_without_examples(true)
18            .optional("range", SyntaxShape::Range, "Range of values.")
19            .category(Category::Random)
20    }
21
22    fn description(&self) -> &str {
23        "Generate a random float within a range [min..max]."
24    }
25
26    fn search_terms(&self) -> Vec<&str> {
27        vec!["generate"]
28    }
29
30    fn run(
31        &self,
32        engine_state: &EngineState,
33        stack: &mut Stack,
34        call: &Call,
35        _input: PipelineData,
36    ) -> Result<PipelineData, ShellError> {
37        float(engine_state, stack, call)
38    }
39
40    fn examples(&self) -> Vec<Example> {
41        vec![
42            Example {
43                description: "Generate a default float value between 0 and 1",
44                example: "random float",
45                result: None,
46            },
47            Example {
48                description: "Generate a random float less than or equal to 500",
49                example: "random float ..500",
50                result: None,
51            },
52            Example {
53                description: "Generate a random float greater than or equal to 100000",
54                example: "random float 100000..",
55                result: None,
56            },
57            Example {
58                description: "Generate a random float between 1.0 and 1.1",
59                example: "random float 1.0..1.1",
60                result: None,
61            },
62        ]
63    }
64}
65
66fn float(
67    engine_state: &EngineState,
68    stack: &mut Stack,
69    call: &Call,
70) -> Result<PipelineData, ShellError> {
71    let span = call.head;
72    let range: Option<Spanned<Range>> = call.opt(engine_state, stack, 0)?;
73
74    match range {
75        Some(range) => {
76            let range_span = range.span;
77            let range = FloatRange::from(range.item);
78
79            if range.step() < 0.0 {
80                return Err(ShellError::InvalidRange {
81                    left_flank: range.start().to_string(),
82                    right_flank: match range.end() {
83                        Bound::Included(end) | Bound::Excluded(end) => end.to_string(),
84                        Bound::Unbounded => "".into(),
85                    },
86                    span: range_span,
87                });
88            }
89
90            let value = match range.end() {
91                Bound::Included(end) => random_range(range.start()..=end),
92                Bound::Excluded(end) => random_range(range.start()..end),
93                Bound::Unbounded => random_range(range.start()..f64::MAX),
94            };
95
96            Ok(PipelineData::Value(Value::float(value, span), None))
97        }
98        None => Ok(PipelineData::Value(
99            Value::float(random_range(0.0..1.0), span),
100            None,
101        )),
102    }
103}
104
105#[cfg(test)]
106mod test {
107    use super::*;
108
109    #[test]
110    fn test_examples() {
111        use crate::test_examples;
112
113        test_examples(RandomFloat {})
114    }
115}
nu_command/random/float.rs

nu_command/random/
float.rs
