Fix utils::prefix
And add a few tests
@@ -50,16 +50,12 @@ pub fn prefix<'a, I>(iter: I, available_width: usize, delimiter: &str) -> Prefix
let mut current_width = 0;
let sum = iter.take_while(|token| {
- let needed_width = if current_width == 0 {
- token.width()
- } else {
- // We also need to insert the delimiter, if not at the beginning.
- token.width() + delimiter_width
- };
- if current_width + needed_width > available_width {
+ let width = token.width();
+ if current_width + width > available_width {
false
} else {
- current_width += needed_width;
+ current_width += width;
+ current_width += delimiter_width;
true
}
})
@@ -70,7 +66,7 @@ pub fn prefix<'a, I>(iter: I, available_width: usize, delimiter: &str) -> Prefix
// but only if the iterator was non empty.
let length = sum.saturating_sub(delimiter_len);
- debug_assert!(current_width <= available_width);
+ debug_assert!(current_width <= available_width + delimiter_width);
Prefix {
length: length,
@@ -98,3 +94,15 @@ pub fn suffix<'a, I>(iter: I, width: usize, delimiter: &str) -> Prefix
pub fn simple_suffix(text: &str, width: usize) -> Prefix {
suffix(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);
+ }
+}
