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

use crate::prelude::*;
use nu_engine::WholeStreamCommand;
use nu_errors::ShellError;
use nu_protocol::ShellTypeName;
use nu_protocol::{
    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
};
use nu_source::{Tag, Tagged};
use nu_value_ext::ValueExt;
use regex::Regex;

struct Arguments {
    all: bool,
    find: Tagged<String>,
    replace: Tagged<String>,
    column_paths: Vec<ColumnPath>,
}

pub struct SubCommand;

impl WholeStreamCommand for SubCommand {
    fn name(&self) -> &str {
        "str find-replace"
    }

    fn signature(&self) -> Signature {
        Signature::build("str find-replace")
            .required("find", SyntaxShape::String, "the pattern to find")
            .required("replace", SyntaxShape::String, "the replacement pattern")
            .rest(
                "rest",
                SyntaxShape::ColumnPath,
                "optionally find and replace text by column paths",
            )
            .switch("all", "replace all occurrences of find string", Some('a'))
    }

    fn usage(&self) -> &str {
        "finds and replaces text"
    }

    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
        operate(args)
    }

    fn examples(&self) -> Vec<Example> {
        vec![
            Example {
                description: "Find and replace contents with capture group",
                example: "echo 'my_library.rb' | str find-replace '(.+).rb' '$1.nu'",
                result: Some(vec![Value::from("my_library.nu")]),
            },
            Example {
                description: "Find and replace all occurrences of find string",
                example: "echo 'abc abc abc' | str find-replace -a 'b' 'z'",
                result: Some(vec![Value::from("azc azc azc")]),
            },
        ]
    }
}

struct FindReplace<'a>(&'a str, &'a str);

fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
    let (options, input) = (
        Arc::new(Arguments {
            all: args.has_flag("all"),
            find: args.req(0)?,
            replace: args.req(1)?,
            column_paths: args.rest(2)?,
        }),
        args.input,
    );

    Ok(input
        .map(move |v| {
            if options.column_paths.is_empty() {
                ReturnSuccess::value(action(&v, &options, v.tag())?)
            } else {
                let mut ret = v;

                for path in &options.column_paths {
                    let options = options.clone();

                    ret = ret.swap_data_by_column_path(
                        path,
                        Box::new(move |old| action(old, &options, old.tag())),
                    )?;
                }

                ReturnSuccess::value(ret)
            }
        })
        .into_action_stream())
}

fn action(
    input: &Value,
    Arguments {
        find, replace, all, ..
    }: &Arguments,
    tag: impl Into<Tag>,
) -> Result<Value, ShellError> {
    match &input.value {
        UntaggedValue::Primitive(Primitive::String(s)) => {
            let FindReplace(find, replacement) = FindReplace(find, replace);
            let regex = Regex::new(find);

            Ok(match regex {
                Ok(re) => {
                    if *all {
                        UntaggedValue::string(re.replace_all(s, replacement).to_owned())
                    } else {
                        UntaggedValue::string(re.replace(s, replacement).to_owned())
                    }
                }
                Err(_) => UntaggedValue::string(s),
            }
            .into_value(tag))
        }
        other => {
            let got = format!("got {}", other.type_name());
            Err(ShellError::labeled_error(
                "value is not string",
                got,
                tag.into().span,
            ))
        }
    }
}

#[cfg(test)]
mod tests {
    use super::ShellError;
    use super::{action, Arguments, SubCommand};
    use nu_source::{Tag, TaggedItem};
    use nu_test_support::value::string;

    #[test]
    fn examples_work_as_expected() -> Result<(), ShellError> {
        use crate::examples::test as test_examples;

        test_examples(SubCommand {})
    }

    #[test]
    fn can_have_capture_groups() {
        let word = string("Cargo.toml");

        let options = Arguments {
            find: String::from("Cargo.(.+)").tagged_unknown(),
            replace: String::from("Carga.$1").tagged_unknown(),
            column_paths: vec![],
            all: false,
        };

        let actual = action(&word, &options, Tag::unknown()).unwrap();
        assert_eq!(actual, string("Carga.toml"));
    }
}