geam 0.1.1

Experimental Rust-embedded execution runtime for typed Gleam programs
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

mod inspect;
mod slice;
mod unicode;

pub(super) use self::inspect::do_inspect;
pub(super) use self::slice::{erl_split, erl_trim, grapheme_slice, unsafe_byte_slice};
pub(super) use self::unicode::{
    from_utf_codepoints, pop_grapheme, unsafe_int_to_utf_codepoint, utf_codepoint_to_int,
};

use crate::gleam_stdlib::{StringTreeExternalStorage, StringTreeSchema};
use crate::{HostExternalBinding, HostProvider};
use ecow::EcoString;
use num_bigint::BigInt;
use std::marker::PhantomData;

pub(super) struct StringProvider<Profile>(PhantomData<Profile>);

impl<Profile> HostProvider<Profile> for StringProvider<Profile>
where
    Profile: super::super::GleamStdlibHostProfile,
{
    type State = Profile::RunState;

    fn project(state: &mut Profile::RunState) -> &mut Self::State {
        state
    }
}

impl<Profile> HostExternalBinding<Profile, StringTreeSchema> for StringProvider<Profile>
where
    Profile: super::super::GleamStdlibHostProfile,
{
    type Storage = StringTreeExternalStorage;
}

pub(super) fn length(string: EcoString) -> BigInt {
    BigInt::from(
        unicode_segmentation::UnicodeSegmentation::graphemes(string.as_str(), true).count(),
    )
}

pub(super) fn lowercase(string: EcoString) -> EcoString {
    string.to_lowercase()
}

pub(super) fn uppercase(string: EcoString) -> EcoString {
    string.to_uppercase()
}

pub(super) fn less_than(left: EcoString, right: EcoString) -> bool {
    left < right
}

pub(super) fn crop(string: EcoString, substring: EcoString) -> EcoString {
    match string.find(substring.as_str()) {
        Some(index) => string[index..].into(),
        None => string,
    }
}

pub(super) fn contains(haystack: EcoString, needle: EcoString) -> bool {
    haystack.contains(needle.as_str())
}

pub(super) fn starts_with(string: EcoString, prefix: EcoString) -> bool {
    string.starts_with(prefix.as_str())
}

pub(super) fn ends_with(string: EcoString, suffix: EcoString) -> bool {
    string.ends_with(suffix.as_str())
}

pub(super) fn byte_size(string: EcoString) -> BigInt {
    BigInt::from(string.len())
}

pub(super) fn remove_prefix(string: EcoString, prefix: EcoString) -> EcoString {
    string
        .strip_prefix(prefix.as_str())
        .map(EcoString::from)
        .unwrap_or(string)
}

pub(super) fn remove_suffix(string: EcoString, suffix: EcoString) -> EcoString {
    string
        .strip_suffix(suffix.as_str())
        .map(EcoString::from)
        .unwrap_or(string)
}

#[cfg(test)]
mod tests {
    use super::{
        StringProvider, byte_size, contains, crop, ends_with, length, less_than, lowercase,
        remove_prefix, remove_suffix, starts_with, uppercase,
    };
    use crate::HostProvider;
    use crate::gleam_stdlib::{GleamStdlibProfile, GleamStdlibRunState};
    use num_bigint::BigInt;

    #[test]
    fn projects_the_stdlib_run_state() {
        let mut state = GleamStdlibRunState::from_seed([0; 32]);
        let original = std::ptr::from_ref(&state);
        let projected =
            <StringProvider<GleamStdlibProfile> as HostProvider<GleamStdlibProfile>>::project(
                &mut state,
            );

        assert_eq!(std::ptr::from_mut(projected).cast_const(), original);
    }

    #[test]
    fn applies_scalar_string_semantics() {
        assert_eq!(length("A👍🏽e\u{301}".into()), BigInt::from(3));
        assert_eq!(lowercase("Gleam İ".into()), "gleam i\u{307}");
        assert_eq!(uppercase("Gleam ß".into()), "GLEAM SS");
        assert!(less_than("A".into(), "B".into()));
        assert!(!less_than("B".into(), "A".into()));
        assert_eq!(crop("The Lone Gunmen".into(), "Lone".into()), "Lone Gunmen");
        assert_eq!(
            crop("The Lone Gunmen".into(), "Fox".into()),
            "The Lone Gunmen"
        );
        assert!(contains("theory".into(), "ory".into()));
        assert!(!contains("theory".into(), "THE".into()));
        assert!(starts_with("theory".into(), "the".into()));
        assert!(ends_with("theory".into(), "ory".into()));
        assert_eq!(byte_size("👍".into()), BigInt::from(4));
        assert_eq!(remove_prefix("@lpil".into(), "@".into()), "lpil");
        assert_eq!(remove_prefix("hello!".into(), "@".into()), "hello!");
        assert_eq!(remove_suffix("Hello!".into(), "!".into()), "Hello");
        assert_eq!(remove_suffix("Hello!?".into(), "!".into()), "Hello!?");
    }
}