nu_command/path/
join.rs

1use super::PathSubcommandArguments;
2use nu_engine::command_prelude::*;
3use nu_protocol::engine::StateWorkingSet;
4use std::path::{Path, PathBuf};
5
6struct Arguments {
7    append: Vec<Spanned<String>>,
8}
9
10impl PathSubcommandArguments for Arguments {}
11
12#[derive(Clone)]
13pub struct PathJoin;
14
15impl Command for PathJoin {
16    fn name(&self) -> &str {
17        "path join"
18    }
19
20    fn signature(&self) -> Signature {
21        Signature::build("path join")
22            .input_output_types(vec![
23                (Type::String, Type::String),
24                (Type::List(Box::new(Type::String)), Type::String),
25                (Type::record(), Type::String),
26                (Type::table(), Type::List(Box::new(Type::String))),
27            ])
28            .rest(
29                "append",
30                SyntaxShape::String,
31                "Path to append to the input.",
32            )
33            .category(Category::Path)
34    }
35
36    fn description(&self) -> &str {
37        "Join a structured path or a list of path parts."
38    }
39
40    fn extra_description(&self) -> &str {
41        r#"Optionally, append an additional path to the result. It is designed to accept
42the output of 'path parse' and 'path split' subcommands."#
43    }
44
45    fn is_const(&self) -> bool {
46        true
47    }
48
49    fn run(
50        &self,
51        engine_state: &EngineState,
52        stack: &mut Stack,
53        call: &Call,
54        input: PipelineData,
55    ) -> Result<PipelineData, ShellError> {
56        let args = Arguments {
57            append: call.rest(engine_state, stack, 0)?,
58        };
59
60        run(call, &args, input)
61    }
62
63    fn run_const(
64        &self,
65        working_set: &StateWorkingSet,
66        call: &Call,
67        input: PipelineData,
68    ) -> Result<PipelineData, ShellError> {
69        let args = Arguments {
70            append: call.rest_const(working_set, 0)?,
71        };
72
73        run(call, &args, input)
74    }
75
76    #[cfg(windows)]
77    fn examples(&self) -> Vec<Example<'_>> {
78        vec![
79            Example {
80                description: "Append a filename to a path",
81                example: r"'C:\Users\viking' | path join spam.txt",
82                result: Some(Value::test_string(r"C:\Users\viking\spam.txt")),
83            },
84            Example {
85                description: "Append a filename to a path",
86                example: r"'C:\Users\viking' | path join spams this_spam.txt",
87                result: Some(Value::test_string(r"C:\Users\viking\spams\this_spam.txt")),
88            },
89            Example {
90                description: "Use relative paths, e.g. '..' will go up one directory",
91                example: r"'C:\Users\viking' | path join .. folder",
92                result: Some(Value::test_string(r"C:\Users\viking\..\folder")),
93            },
94            Example {
95                description: "Use absolute paths, e.g. '/' will bring you to the top level directory",
96                example: r"'C:\Users\viking' | path join / folder",
97                result: Some(Value::test_string(r"C:/folder")),
98            },
99            Example {
100                description: "Join a list of parts into a path",
101                example: r"[ 'C:' '\' 'Users' 'viking' 'spam.txt' ] | path join",
102                result: Some(Value::test_string(r"C:\Users\viking\spam.txt")),
103            },
104            Example {
105                description: "Join a structured path into a path",
106                example: r"{ parent: 'C:\Users\viking', stem: 'spam', extension: 'txt' } | path join",
107                result: Some(Value::test_string(r"C:\Users\viking\spam.txt")),
108            },
109            Example {
110                description: "Join a table of structured paths into a list of paths",
111                example: r"[ [parent stem extension]; ['C:\Users\viking' 'spam' 'txt']] | path join",
112                result: Some(Value::list(
113                    vec![Value::test_string(r"C:\Users\viking\spam.txt")],
114                    Span::test_data(),
115                )),
116            },
117        ]
118    }
119
120    #[cfg(not(windows))]
121    fn examples(&self) -> Vec<Example<'_>> {
122        vec![
123            Example {
124                description: "Append a filename to a path",
125                example: r"'/home/viking' | path join spam.txt",
126                result: Some(Value::test_string(r"/home/viking/spam.txt")),
127            },
128            Example {
129                description: "Append a filename to a path",
130                example: r"'/home/viking' | path join spams this_spam.txt",
131                result: Some(Value::test_string(r"/home/viking/spams/this_spam.txt")),
132            },
133            Example {
134                description: "Use relative paths, e.g. '..' will go up one directory",
135                example: r"'/home/viking' | path join .. folder",
136                result: Some(Value::test_string(r"/home/viking/../folder")),
137            },
138            Example {
139                description: "Use absolute paths, e.g. '/' will bring you to the top level directory",
140                example: r"'/home/viking' | path join / folder",
141                result: Some(Value::test_string(r"/folder")),
142            },
143            Example {
144                description: "Join a list of parts into a path",
145                example: r"[ '/' 'home' 'viking' 'spam.txt' ] | path join",
146                result: Some(Value::test_string(r"/home/viking/spam.txt")),
147            },
148            Example {
149                description: "Join a structured path into a path",
150                example: r"{ parent: '/home/viking', stem: 'spam', extension: 'txt' } | path join",
151                result: Some(Value::test_string(r"/home/viking/spam.txt")),
152            },
153            Example {
154                description: "Join a table of structured paths into a list of paths",
155                example: r"[[ parent stem extension ]; [ '/home/viking' 'spam' 'txt' ]] | path join",
156                result: Some(Value::list(
157                    vec![Value::test_string(r"/home/viking/spam.txt")],
158                    Span::test_data(),
159                )),
160            },
161        ]
162    }
163}
164
165fn run(call: &Call, args: &Arguments, input: PipelineData) -> Result<PipelineData, ShellError> {
166    let head = call.head;
167
168    let metadata = input.metadata();
169
170    match input {
171        PipelineData::Value(val, md) => Ok(PipelineData::value(handle_value(val, args, head), md)),
172        PipelineData::ListStream(stream, ..) => Ok(PipelineData::value(
173            handle_value(stream.into_value()?, args, head),
174            metadata,
175        )),
176        PipelineData::ByteStream(stream, ..) => Ok(PipelineData::value(
177            handle_value(stream.into_value()?, args, head),
178            metadata,
179        )),
180        PipelineData::Empty => Err(ShellError::PipelineEmpty { dst_span: head }),
181    }
182}
183
184fn handle_value(v: Value, args: &Arguments, head: Span) -> Value {
185    let span = v.span();
186    match v {
187        Value::String { ref val, .. } => join_single(Path::new(val), head, args),
188        Value::Record { val, .. } => join_record(&val, head, span, args),
189        Value::List { vals, .. } => join_list(&vals, head, span, args),
190
191        _ => super::handle_invalid_values(v, head),
192    }
193}
194
195fn join_single(path: &Path, head: Span, args: &Arguments) -> Value {
196    let mut result = path.to_path_buf();
197    for path_to_append in &args.append {
198        result.push(&path_to_append.item)
199    }
200
201    Value::string(result.to_string_lossy(), head)
202}
203
204fn join_list(parts: &[Value], head: Span, span: Span, args: &Arguments) -> Value {
205    let path: Result<PathBuf, ShellError> = parts.iter().map(Value::coerce_string).collect();
206
207    match path {
208        Ok(ref path) => join_single(path, head, args),
209        Err(_) => {
210            let records: Result<Vec<_>, ShellError> = parts.iter().map(Value::as_record).collect();
211            match records {
212                Ok(vals) => {
213                    let vals = vals
214                        .iter()
215                        .map(|r| join_record(r, head, span, args))
216                        .collect();
217
218                    Value::list(vals, span)
219                }
220                Err(ShellError::CantConvert { from_type, .. }) => Value::error(
221                    ShellError::OnlySupportsThisInputType {
222                        exp_input_type: "string or record".into(),
223                        wrong_type: from_type,
224                        dst_span: head,
225                        src_span: span,
226                    },
227                    span,
228                ),
229                Err(_) => Value::error(
230                    ShellError::NushellFailed {
231                        msg: "failed to join path".into(),
232                    },
233                    span,
234                ),
235            }
236        }
237    }
238}
239
240fn join_record(record: &Record, head: Span, span: Span, args: &Arguments) -> Value {
241    match merge_record(record, head, span) {
242        Ok(p) => join_single(p.as_path(), head, args),
243        Err(error) => Value::error(error, span),
244    }
245}
246
247fn merge_record(record: &Record, head: Span, span: Span) -> Result<PathBuf, ShellError> {
248    for key in record.columns() {
249        if !super::ALLOWED_COLUMNS.contains(&key.as_str()) {
250            let allowed_cols = super::ALLOWED_COLUMNS.join(", ");
251            return Err(ShellError::UnsupportedInput {
252                msg: format!(
253                    "Column '{key}' is not valid for a structured path. Allowed columns on this platform are: {allowed_cols}"
254                ),
255                input: "value originates from here".into(),
256                msg_span: head,
257                input_span: span,
258            });
259        }
260    }
261
262    let mut result = PathBuf::new();
263
264    #[cfg(windows)]
265    if let Some(val) = record.get("prefix") {
266        let p = val.coerce_str()?;
267        if !p.is_empty() {
268            result.push(p.as_ref());
269        }
270    }
271
272    if let Some(val) = record.get("parent") {
273        let p = val.coerce_str()?;
274        if !p.is_empty() {
275            result.push(p.as_ref());
276        }
277    }
278
279    let mut basename = String::new();
280    if let Some(val) = record.get("stem") {
281        let p = val.coerce_str()?;
282        if !p.is_empty() {
283            basename.push_str(&p);
284        }
285    }
286
287    if let Some(val) = record.get("extension") {
288        let p = val.coerce_str()?;
289        if !p.is_empty() {
290            basename.push('.');
291            basename.push_str(&p);
292        }
293    }
294
295    if !basename.is_empty() {
296        result.push(basename);
297    }
298
299    Ok(result)
300}
301
302#[cfg(test)]
303mod tests {
304    use super::*;
305
306    #[test]
307    fn test_examples() {
308        use crate::test_examples;
309
310        test_examples(PathJoin {})
311    }
312}