steward/
env.rs

1use std::collections::{hash_map, HashMap};
2
3/// Environment data for a [`Cmd`](crate::Cmd).
4#[derive(Clone)]
5pub struct Env(HashMap<String, String>);
6
7impl Env {
8    /// Constructs a new container from a [`HashMap`](HashMap).
9    pub fn new(data: HashMap<String, String>) -> Self {
10        Self(data)
11    }
12
13    /// Constructs a new empty container.
14    pub fn empty() -> Self {
15        Self(HashMap::new())
16    }
17
18    /// Constructs a new container from a [`Vec`](Vec).
19    pub fn from_vec<K: ToString, V: ToString>(kvs: Vec<(K, V)>) -> Self {
20        let mut data = HashMap::with_capacity(kvs.len());
21        for (k, v) in kvs {
22            data.insert(k.to_string(), v.to_string());
23        }
24        Self(data)
25    }
26
27    /// Constructs a new container with one entry.
28    pub fn one<K: ToString, V: ToString>(k: K, v: V) -> Self {
29        let mut data = HashMap::with_capacity(1);
30        data.insert(k.to_string(), v.to_string());
31        Self(data)
32    }
33
34    /// Constructs a new container with data from an environment of the current process.
35    pub fn parent() -> Self {
36        let env = std::env::vars();
37        let mut data = HashMap::new();
38        for (k, v) in env {
39            data.insert(k, v);
40        }
41        Self(data)
42    }
43
44    /// Inserts one entry into existing container by mutating it.
45    pub fn insert<K: ToString, V: ToString>(mut self, k: K, v: V) -> Self {
46        self.0.insert(k.to_string(), v.to_string());
47        self
48    }
49
50    /// Inserts one entry into container by mutating it.
51    pub fn insert_cloned<K: ToString, V: ToString>(&self, k: K, v: V) -> Self {
52        let mut cloned = self.0.clone();
53        cloned.insert(k.to_string(), v.to_string());
54        Self(cloned)
55    }
56
57    /// Merges two containers by mutating the receiver.
58    pub fn extend(mut self, env: Self) -> Self {
59        self.0.extend(env.0);
60        self
61    }
62
63    /// Merges two containers and returns a new cloned one. Doesn't mutate a receiver.
64    pub fn extend_cloned(&self, env: Self) -> Self {
65        Self(self.0.clone().into_iter().chain(env.0).collect())
66    }
67
68    /// Retrives a value from a container by the provided key.
69    pub fn get(&self, k: &str) -> Option<&String> {
70        self.0.get(k)
71    }
72}
73
74impl IntoIterator for Env {
75    type Item = (String, String);
76    type IntoIter = hash_map::IntoIter<String, String>;
77
78    fn into_iter(self) -> Self::IntoIter {
79        self.0.into_iter()
80    }
81}
82
83/// Convenience struct for dealing with the `PATH` environment variable.
84pub struct PATH;
85
86impl PATH {
87    #[cfg(unix)]
88    const DEL: char = ':';
89
90    #[cfg(windows)]
91    const DEL: char = ';';
92
93    /// Gets the `PATH` value from an environment of the current process.
94    pub fn get() -> Option<String> {
95        Env::parent().get("PATH").map(|x| x.to_owned())
96    }
97
98    /// Extends the `PATH` value taken the current process and returns the extended value. It doesn't extend the `PATH` of the current process.
99    pub fn extend(x: impl ToString) -> String {
100        match PATH::get() {
101            Some(path) => format!("{}{}{}", path, PATH::DEL, x.to_string()),
102            None => x.to_string(),
103        }
104    }
105}
steward/env.rs

steward/
env.rs
