find_words_ascii_space(line: &str) -> impl Iterator<Item = &'_ str> + '_1 pub(crate) fn find_words_ascii_space(line: &str) -> impl Iterator<Item = &'_ str> + '_ {
2 let mut start = 0;
3 let mut in_whitespace = false;
4 let mut char_indices = line.char_indices();
5
6 std::iter::from_fn(move || {
7 for (idx, ch) in char_indices.by_ref() {
8 if in_whitespace && ch != ' ' {
9 let word = &line[start..idx];
10 start = idx;
11 in_whitespace = ch == ' ';
12 return Some(word);
13 }
14
15 in_whitespace = ch == ' ';
16 }
17
18 if start < line.len() {
19 let word = &line[start..];
20 start = line.len();
21 return Some(word);
22 }
23
24 None
25 })
26 }
27
28 #[cfg(test)]
29 mod tests {
30 use super::*;
31
32 macro_rules! test_find_words {
33 ($ascii_name:ident,
34 $([ $line:expr, $ascii_words:expr ]),+) => {
35 #[test]
36 fn $ascii_name() {
37 $(
38 let expected_words: Vec<&str> = $ascii_words.to_vec();
39 let actual_words = find_words_ascii_space($line)
40 .collect::<Vec<_>>();
41 assert_eq!(actual_words, expected_words, "Line: {:?}", $line);
42 )+
43 }
44 };
45 }
46
47 test_find_words!(ascii_space_empty, ["", []]);
48
49 test_find_words!(ascii_single_word, ["foo", ["foo"]]);
50
51 test_find_words!(ascii_two_words, ["foo bar", ["foo ", "bar"]]);
52
53 test_find_words!(
54 ascii_multiple_words,
55 ["foo bar", ["foo ", "bar"]],
56 ["x y z", ["x ", "y ", "z"]]
57 );
58
59 test_find_words!(ascii_only_whitespace, [" ", [" "]], [" ", [" "]]);
60
61 test_find_words!(
62 ascii_inter_word_whitespace,
63 ["foo bar", ["foo ", "bar"]]
64 );
65
66 test_find_words!(ascii_trailing_whitespace, ["foo ", ["foo "]]);
67
68 test_find_words!(ascii_leading_whitespace, [" foo", [" ", "foo"]]);
69
70 test_find_words!(
71 ascii_multi_column_char,
72 ["\u{1f920}", ["\u{1f920}"]] // cowboy emoji ��
73 );
74
75 test_find_words!(
76 ascii_hyphens,
77 ["foo-bar", ["foo-bar"]],
78 ["foo- bar", ["foo- ", "bar"]],
79 ["foo - bar", ["foo ", "- ", "bar"]],
80 ["foo -bar", ["foo ", "-bar"]]
81 );
82
83 test_find_words!(ascii_newline, ["foo\nbar", ["foo\nbar"]]);
84
85 test_find_words!(ascii_tab, ["foo\tbar", ["foo\tbar"]]);
86
87 test_find_words!(
88 ascii_non_breaking_space,
89 ["foo\u{00A0}bar", ["foo\u{00A0}bar"]]
90 );
91 }
92