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use unicode_segmentation::UnicodeSegmentation;
use unicode_width::UnicodeWidthStr;
///
pub fn trim_length_left(s: &str, width: usize) -> &str {
let len = s.len();
if len > width {
for i in len - width..len {
if s.is_char_boundary(i) {
return &s[i..];
}
}
}
s
}
//TODO: allow customize tabsize
pub fn tabs_to_spaces(input: String) -> String {
if input.contains('\t') {
input.replace('\t', " ")
} else {
input
}
}
/// This function will return a str slice which start at specified offset.
/// As src is a unicode str, start offset has to be calculated with each character.
pub fn trim_offset(src: &str, mut offset: usize) -> &str {
let mut start = 0;
for c in UnicodeSegmentation::graphemes(src, true) {
let w = c.width();
if w <= offset {
offset -= w;
start += c.len();
} else {
break;
}
}
&src[start..]
}
#[cfg(test)]
mod test {
use pretty_assertions::assert_eq;
use crate::string_utils::trim_length_left;
#[test]
fn test_trim() {
assert_eq!(trim_length_left("👍foo", 3), "foo");
assert_eq!(trim_length_left("👍foo", 4), "foo");
}
}
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