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use unicode_segmentation::UnicodeSegmentation;
use unicode_width::UnicodeWidthStr;
mod lines_iterator;
mod reader;
pub use self::lines_iterator::{LinesIterator, Row};
pub use self::reader::ProgressReader;
pub struct Span {
pub length: usize,
pub width: usize,
}
pub fn prefix<'a, I>(iter: I, available_width: usize, delimiter: &str) -> Span
where
I: Iterator<Item = &'a str>,
{
let delimiter_width = delimiter.width();
let delimiter_len = delimiter.len();
let mut current_width = 0;
let sum: usize = iter.take_while(|token| {
let width = token.width();
if current_width + width > available_width {
false
} else {
current_width += width;
current_width += delimiter_width;
true
}
}).map(|token| token.len() + delimiter_len)
.sum();
let length = sum.saturating_sub(delimiter_len);
debug_assert!(current_width <= available_width + delimiter_width);
Span {
length: length,
width: current_width,
}
}
pub fn suffix<'a, I>(iter: I, width: usize, delimiter: &str) -> Span
where
I: DoubleEndedIterator<Item = &'a str>,
{
prefix(iter.rev(), width, delimiter)
}
pub fn simple_suffix(text: &str, width: usize) -> Span {
suffix(text.graphemes(true), width, "")
}
pub fn simple_prefix(text: &str, width: usize) -> Span {
prefix(text.graphemes(true), width, "")
}
#[cfg(test)]
mod tests {
use utils;
#[test]
fn test_prefix() {
assert_eq!(utils::prefix(" abra ".split(' '), 5, " ").length, 5);
assert_eq!(utils::prefix("abra a".split(' '), 5, " ").length, 4);
assert_eq!(utils::prefix("a a br".split(' '), 5, " ").length, 3);
}
}