summaryrefslogtreecommitdiff
path: root/helix-core/src/path.rs
blob: ede37e044e057d0441259eda67deaabca46c73c3 (plain) (blame)
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
use etcetera::home_dir;
use std::path::{Component, Path, PathBuf};

/// Replaces users home directory from `path` with tilde `~` if the directory
/// is available, otherwise returns the path unchanged.
pub fn fold_home_dir(path: &Path) -> PathBuf {
    if let Ok(home) = home_dir() {
        if let Ok(stripped) = path.strip_prefix(&home) {
            return PathBuf::from("~").join(stripped);
        }
    }

    path.to_path_buf()
}

/// Expands tilde `~` into users home directory if available, otherwise returns the path
/// unchanged. The tilde will only be expanded when present as the first component of the path
/// and only slash follows it.
pub fn expand_tilde(path: &Path) -> PathBuf {
    let mut components = path.components().peekable();
    if let Some(Component::Normal(c)) = components.peek() {
        if c == &"~" {
            if let Ok(home) = home_dir() {
                // it's ok to unwrap, the path starts with `~`
                return home.join(path.strip_prefix("~").unwrap());
            }
        }
    }

    path.to_path_buf()
}

/// Normalize a path, removing things like `.` and `..`.
///
/// CAUTION: This does not resolve symlinks (unlike
/// [`std::fs::canonicalize`]). This may cause incorrect or surprising
/// behavior at times. This should be used carefully. Unfortunately,
/// [`std::fs::canonicalize`] can be hard to use correctly, since it can often
/// fail, or on Windows returns annoying device paths. This is a problem Cargo
/// needs to improve on.
/// Copied from cargo: <https://github.com/rust-lang/cargo/blob/070e459c2d8b79c5b2ac5218064e7603329c92ae/crates/cargo-util/src/paths.rs#L81>
pub fn get_normalized_path(path: &Path) -> PathBuf {
    // normalization strategy is to canonicalize first ancestor path that exists (i.e., canonicalize as much as possible),
    // then run handrolled normalization on the non-existent remainder
    let (base, path) = path
        .ancestors()
        .find_map(|base| {
            let canonicalized_base = dunce::canonicalize(base).ok()?;
            let remainder = path.strip_prefix(base).ok()?.into();
            Some((canonicalized_base, remainder))
        })
        .unwrap_or_else(|| (PathBuf::new(), PathBuf::from(path)));

    if path.as_os_str().is_empty() {
        return base;
    }

    let mut components = path.components().peekable();
    let mut ret = if let Some(c @ Component::Prefix(..)) = components.peek().cloned() {
        components.next();
        PathBuf::from(c.as_os_str())
    } else {
        PathBuf::new()
    };

    for component in components {
        match component {
            Component::Prefix(..) => unreachable!(),
            Component::RootDir => {
                ret.push(component.as_os_str());
            }
            Component::CurDir => {}
            Component::ParentDir => {
                ret.pop();
            }
            Component::Normal(c) => {
                ret.push(c);
            }
        }
    }
    base.join(ret)
}

/// Returns the canonical, absolute form of a path with all intermediate components normalized.
///
/// This function is used instead of `std::fs::canonicalize` because we don't want to verify
/// here if the path exists, just normalize it's components.
pub fn get_canonicalized_path(path: &Path) -> PathBuf {
    let path = expand_tilde(path);
    let path = if path.is_relative() {
        helix_loader::current_working_dir().join(path)
    } else {
        path
    };

    get_normalized_path(path.as_path())
}

pub fn get_relative_path(path: &Path) -> PathBuf {
    let path = PathBuf::from(path);
    let path = if path.is_absolute() {
        let cwdir = get_normalized_path(&helix_loader::current_working_dir());
        get_normalized_path(&path)
            .strip_prefix(cwdir)
            .map(PathBuf::from)
            .unwrap_or(path)
    } else {
        path
    };
    fold_home_dir(&path)
}

/// Returns a truncated filepath where the basepart of the path is reduced to the first
/// char of the folder and the whole filename appended.
///
/// Also strip the current working directory from the beginning of the path.
/// Note that this function does not check if the truncated path is unambiguous.
///
/// ```   
///    use helix_core::path::get_truncated_path;
///    use std::path::Path;
///
///    assert_eq!(
///         get_truncated_path("/home/cnorris/documents/jokes.txt").as_path(),
///         Path::new("/h/c/d/jokes.txt")
///     );
///     assert_eq!(
///         get_truncated_path("jokes.txt").as_path(),
///         Path::new("jokes.txt")
///     );
///     assert_eq!(
///         get_truncated_path("/jokes.txt").as_path(),
///         Path::new("/jokes.txt")
///     );
///     assert_eq!(
///         get_truncated_path("/h/c/d/jokes.txt").as_path(),
///         Path::new("/h/c/d/jokes.txt")
///     );
///     assert_eq!(get_truncated_path("").as_path(), Path::new(""));
/// ```
///
pub fn get_truncated_path<P: AsRef<Path>>(path: P) -> PathBuf {
    let cwd = helix_loader::current_working_dir();
    let path = path
        .as_ref()
        .strip_prefix(cwd)
        .unwrap_or_else(|_| path.as_ref());
    let file = path.file_name().unwrap_or_default();
    let base = path.parent().unwrap_or_else(|| Path::new(""));
    let mut ret = PathBuf::new();
    for d in base {
        ret.push(
            d.to_string_lossy()
                .chars()
                .next()
                .unwrap_or_default()
                .to_string(),
        );
    }
    ret.push(file);
    ret
}