lowdash 0.5.3

A Lodash inspired utility library to manipulate array and object for Rust
Documentation 
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

/// Filters a map by selecting only the specified values.
///
/// Iterates over each key-value pair in the input map and includes it in the result map
/// only if the value is present in the provided values slice.
///
/// # Arguments
/// * `map` - The input map to filter.
/// * `values` - A slice of values to select from the map.
///
/// # Returns
/// * `HashMap<K, V>` - A new map containing only the key-value pairs that have values present in the values slice.
///
/// # Examples
/// ```rust
/// use lowdash::pick_by_values;
/// use std::collections::HashMap;
///
/// let mut map = HashMap::new();
/// map.insert("a", 1);
/// map.insert("b", 2);
/// map.insert("c", 3);
///
/// let values = vec![1, 3];
/// let result = pick_by_values(&map, &values);
/// assert_eq!(result.len(), 2);
/// assert!(result.contains_key("a"));
/// assert!(result.contains_key("c"));
/// ```
pub fn pick_by_values<K, V>(
    map: &std::collections::HashMap<K, V>,
    values: &[V],
) -> std::collections::HashMap<K, V>
where
    K: std::cmp::Eq + std::hash::Hash + Clone,
    V: std::cmp::Eq + std::hash::Hash + Clone,
{
    let value_set: std::collections::HashSet<V> = values.iter().cloned().collect();
    let mut result = std::collections::HashMap::new();
    for (k, v) in map.iter() {
        if value_set.contains(v) {
            result.insert(k.clone(), v.clone());
        }
    }
    result
}

#[cfg(test)]
mod tests {
    use super::*;
    use std::collections::HashMap;

    #[test]
    fn test_pick_by_values_existing_values() {
        let mut map = HashMap::new();
        map.insert("a", 1);
        map.insert("b", 2);
        map.insert("c", 3);

        let values = vec![1, 3];
        let result = pick_by_values(&map, &values);
        assert_eq!(result.len(), 2);
        assert!(result.contains_key("a"));
        assert!(result.contains_key("c"));
    }

    #[test]
    fn test_pick_by_values_some_missing_values() {
        let mut map = HashMap::new();
        map.insert("a", 1);
        map.insert("b", 2);

        let values = vec![1, 3];
        let result = pick_by_values(&map, &values);
        assert_eq!(result.len(), 1);
        assert!(result.contains_key("a"));
        assert!(!result.contains_key("b"));
    }

    #[test]
    fn test_pick_by_values_all_missing_values() {
        let mut map = HashMap::new();
        map.insert("a", 1);
        map.insert("b", 2);

        let values = vec![3, 4];
        let result = pick_by_values(&map, &values);
        assert_eq!(result.len(), 0);
    }

    #[test]
    fn test_pick_by_values_empty_values() {
        let mut map = HashMap::new();
        map.insert("a", 1);
        map.insert("b", 2);

        let values: Vec<i32> = vec![];
        let result = pick_by_values(&map, &values);
        assert_eq!(result.len(), 0);
    }

    #[test]
    fn test_pick_by_values_empty_map() {
        let map: HashMap<&str, i32> = HashMap::new();
        let values = vec![1, 2];
        let result = pick_by_values(&map, &values);
        assert_eq!(result.len(), 0);
    }

    #[test]
    fn test_pick_by_values_with_strings() {
        let mut map = HashMap::new();
        map.insert("apple", "red");
        map.insert("banana", "yellow");
        map.insert("grape", "purple");

        let values = vec!["red", "purple"];
        let result = pick_by_values(&map, &values);
        assert_eq!(result.len(), 2);
        assert!(result.contains_key("apple"));
        assert!(result.contains_key("grape"));
    }

    #[test]
    fn test_pick_by_values_with_mixed_types() {
        let mut map = HashMap::new();
        map.insert(1, "one");
        map.insert(2, "two");
        map.insert(3, "three");

        let values = vec!["one", "three", "four"];
        let result = pick_by_values(&map, &values);
        assert_eq!(result.len(), 2);
        assert!(result.contains_key(&1));
        assert!(result.contains_key(&3));
        assert!(!result.contains_key(&2));
    }
}