1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175

use nu_engine::CallExt;
use nu_protocol::{
    ast::{Call, CellPath},
    engine::{Command, EngineState, Stack},
    Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
};

#[derive(Clone)]
pub struct SubCommand;

impl Command for SubCommand {
    fn name(&self) -> &str {
        "into decimal"
    }

    fn signature(&self) -> Signature {
        Signature::build("into decimal").rest(
            "rest",
            SyntaxShape::CellPath,
            "optionally convert text into decimal by column paths",
        )
    }

    fn usage(&self) -> &str {
        "Convert text into a decimal"
    }

    fn search_terms(&self) -> Vec<&str> {
        vec!["convert", "number", "floating"]
    }

    fn run(
        &self,
        engine_state: &EngineState,
        stack: &mut Stack,
        call: &Call,
        input: PipelineData,
    ) -> Result<nu_protocol::PipelineData, nu_protocol::ShellError> {
        operate(engine_state, stack, call, input)
    }

    fn examples(&self) -> Vec<Example> {
        vec![
            Example {
                description: "Convert string to integer in table",
                example: "[[num]; ['5.01']] | into decimal num",
                result: Some(Value::List {
                    vals: vec![Value::Record {
                        cols: vec!["num".to_string()],
                        vals: vec![Value::test_float(5.01)],
                        span: Span::test_data(),
                    }],
                    span: Span::test_data(),
                }),
            },
            Example {
                description: "Convert string to integer",
                example: "'1.345' | into decimal",
                result: Some(Value::test_float(1.345)),
            },
            Example {
                description: "Convert decimal to integer",
                example: "'-5.9' | into decimal",
                result: Some(Value::test_float(-5.9)),
            },
        ]
    }
}

fn operate(
    engine_state: &EngineState,
    stack: &mut Stack,
    call: &Call,
    input: PipelineData,
) -> Result<nu_protocol::PipelineData, nu_protocol::ShellError> {
    let head = call.head;
    let column_paths: Vec<CellPath> = call.rest(engine_state, stack, 0)?;

    input.map(
        move |v| {
            if column_paths.is_empty() {
                action(&v, head)
            } else {
                let mut ret = v;
                for path in &column_paths {
                    let r =
                        ret.update_cell_path(&path.members, Box::new(move |old| action(old, head)));
                    if let Err(error) = r {
                        return Value::Error { error };
                    }
                }

                ret
            }
        },
        engine_state.ctrlc.clone(),
    )
}

fn action(input: &Value, head: Span) -> Value {
    match input {
        Value::String { val: s, span } => {
            let other = s.trim();

            match other.parse::<f64>() {
                Ok(x) => Value::Float { val: x, span: head },
                Err(reason) => Value::Error {
                    error: ShellError::CantConvert(
                        "float".to_string(),
                        reason.to_string(),
                        *span,
                        None,
                    ),
                },
            }
        }
        Value::Int { val: v, span } => Value::Float {
            val: *v as f64,
            span: *span,
        },
        other => {
            let span = other.span();
            match span {
                Ok(s) => {
                    let got = format!("Expected a string, got {} instead", other.get_type());
                    Value::Error {
                        error: ShellError::UnsupportedInput(got, s),
                    }
                }
                Err(e) => Value::Error { error: e },
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use nu_protocol::Type::Error;

    #[test]
    fn test_examples() {
        use crate::test_examples;

        test_examples(SubCommand {})
    }

    #[test]
    #[allow(clippy::approx_constant)]
    fn string_to_decimal() {
        let word = Value::test_string("3.1415");
        let expected = Value::test_float(3.1415);

        let actual = action(&word, Span::test_data());
        assert_eq!(actual, expected);
    }

    #[test]
    fn communicates_parsing_error_given_an_invalid_decimallike_string() {
        let decimal_str = Value::test_string("11.6anra");

        let actual = action(&decimal_str, Span::test_data());

        assert_eq!(actual.get_type(), Error);
    }

    #[test]
    fn int_to_decimal() {
        let decimal_str = Value::test_int(10);
        let expected = Value::test_float(10.0);
        let actual = action(&decimal_str, Span::test_data());

        assert_eq!(actual, expected);
    }
}