diff --git a/src/highlight.rs b/src/highlight.rs index 545f9a9..5444140 100644 --- a/src/highlight.rs +++ b/src/highlight.rs @@ -40,39 +40,54 @@ impl Boundary { } } -fn line_display_text(s: &str, tab_len: u8, mask: Option) -> Cow<'_, str> { - if let Some(ch) = mask { - // No tab character processing in the mask case - let masked = iter::repeat(ch).take(s.chars().count()).collect(); - return Cow::Owned(masked); - } +struct DisplayTextBuilder { + tab_len: u8, + width: usize, + mask: Option, +} - let tab = spaces(tab_len); - let mut buf = String::new(); - let mut width = 0; - for (i, c) in s.char_indices() { - if c == '\t' { - if buf.is_empty() { - buf.reserve(s.len()); - buf.push_str(&s[..i]); - } - if tab_len > 0 { - let len = tab_len as usize - (width % tab_len as usize); - buf.push_str(&tab[..len]); - width += len; - } - } else { - if !buf.is_empty() { - buf.push(c); - } - width += c.width().unwrap_or(0); +impl DisplayTextBuilder { + fn new(tab_len: u8, mask: Option) -> Self { + Self { + tab_len, + width: 0, + mask, } } - if !buf.is_empty() { - Cow::Owned(buf) - } else { - Cow::Borrowed(s) + fn build<'s>(&mut self, s: &'s str) -> Cow<'s, str> { + if let Some(ch) = self.mask { + // No tab character processing in the mask case + let masked = iter::repeat(ch).take(s.chars().count()).collect(); + return Cow::Owned(masked); + } + + let tab = spaces(self.tab_len); + let mut buf = String::new(); + for (i, c) in s.char_indices() { + if c == '\t' { + if buf.is_empty() { + buf.reserve(s.len()); + buf.push_str(&s[..i]); + } + if self.tab_len > 0 { + let len = self.tab_len as usize - (self.width % self.tab_len as usize); + buf.push_str(&tab[..len]); + self.width += len; + } + } else { + if !buf.is_empty() { + buf.push(c); + } + self.width += c.width().unwrap_or(0); + } + } + + if !buf.is_empty() { + Cow::Owned(buf) + } else { + Cow::Borrowed(s) + } } } @@ -139,12 +154,10 @@ impl<'a> LineHighlighter<'a> { cursor_at_end, mask, } = self; + let mut builder = DisplayTextBuilder::new(tab_len, mask); if boundaries.is_empty() { - spans.push(Span::styled( - line_display_text(line, tab_len, mask), - style_begin, - )); + spans.push(Span::styled(builder.build(line), style_begin)); if cursor_at_end { spans.push(Span::styled(" ", cursor_style)); } @@ -161,87 +174,122 @@ impl<'a> LineHighlighter<'a> { let mut start = 0; let mut stack = vec![]; - loop { - if let Some((next_boundary, end)) = boundaries.next() { - if start < end { - spans.push(Span::styled( - line_display_text(&line[start..end], tab_len, mask), - style, - )); - } - - style = if let Some(s) = next_boundary.style() { - stack.push(style); - s - } else { - stack.pop().unwrap_or(style_begin) - }; - start = end; - } else { - if start != line.len() { - spans.push(Span::styled( - line_display_text(&line[start..], tab_len, mask), - style, - )); - } - if cursor_at_end { - spans.push(Span::styled(" ", cursor_style)); - } - return Line::from(spans); + while let Some((next_boundary, end)) = boundaries.next() { + if start < end { + spans.push(Span::styled(builder.build(&line[start..end]), style)); } + + style = if let Some(s) = next_boundary.style() { + stack.push(style); + s + } else { + stack.pop().unwrap_or(style_begin) + }; + start = end; } + + if start != line.len() { + spans.push(Span::styled(builder.build(&line[start..]), style)); + } + if cursor_at_end { + spans.push(Span::styled(" ", cursor_style)); + } + Line::from(spans) } } + #[cfg(test)] mod tests { use super::*; + #[track_caller] + fn build(text: &'static str, tab: u8, mask: Option) -> Cow<'static, str> { + DisplayTextBuilder::new(tab, mask).build(text) + } + + #[track_caller] + fn build_with_offset(offset: usize, text: &'static str, tab: u8) -> (Cow<'static, str>, usize) { + let mut b = DisplayTextBuilder::new(tab, None); + b.width = offset; + (b.build(text), b.width) + } + #[test] #[rustfmt::skip] fn test_line_display_text() { - assert_eq!(&line_display_text( "", 0, None), ""); - assert_eq!(&line_display_text( "", 4, None), ""); - assert_eq!(&line_display_text( "", 8, None), ""); - assert_eq!(&line_display_text( "", 0, Some('x')), ""); - assert_eq!(&line_display_text( "", 4, Some('x')), ""); - assert_eq!(&line_display_text( "", 8, Some('x')), ""); - assert_eq!(&line_display_text( "a", 0, None), "a"); - assert_eq!(&line_display_text( "a", 4, None), "a"); - assert_eq!(&line_display_text( "a", 8, None), "a"); - assert_eq!(&line_display_text( "a", 0, Some('x')), "x"); - assert_eq!(&line_display_text( "a", 4, Some('x')), "x"); - assert_eq!(&line_display_text( "a", 8, Some('x')), "x"); - assert_eq!(&line_display_text( "a\t", 0, None), "a"); - assert_eq!(&line_display_text( "a\t", 4, None), "a "); - assert_eq!(&line_display_text( "a\t", 8, None), "a "); - assert_eq!(&line_display_text( "a\t", 0, Some('x')), "xx"); - assert_eq!(&line_display_text( "a\t", 4, Some('x')), "xx"); - assert_eq!(&line_display_text( "a\t", 8, Some('x')), "xx"); - assert_eq!(&line_display_text( "\t", 0, None), "\t"); - assert_eq!(&line_display_text( "\t", 4, None), " "); - assert_eq!(&line_display_text( "\t", 8, None), " "); - assert_eq!(&line_display_text( "\t", 0, Some('x')), "x"); - assert_eq!(&line_display_text( "\t", 4, Some('x')), "x"); - assert_eq!(&line_display_text( "\t", 8, Some('x')), "x"); - assert_eq!(&line_display_text( "a\tb", 0, None), "ab"); - assert_eq!(&line_display_text( "a\tb", 4, None), "a b"); - assert_eq!(&line_display_text( "a\tb", 8, None), "a b"); - assert_eq!(&line_display_text( "a\tb", 0, Some('x')), "xxx"); - assert_eq!(&line_display_text( "a\tb", 4, Some('x')), "xxx"); - assert_eq!(&line_display_text( "a\tb", 8, Some('x')), "xxx"); - assert_eq!(&line_display_text("a\t\tb", 0, None), "ab"); - assert_eq!(&line_display_text("a\t\tb", 4, None), "a b"); - assert_eq!(&line_display_text("a\t\tb", 8, None), "a b"); - assert_eq!(&line_display_text("a\t\tb", 0, Some('x')), "xxxx"); - assert_eq!(&line_display_text("a\t\tb", 4, Some('x')), "xxxx"); - assert_eq!(&line_display_text("a\t\tb", 8, Some('x')), "xxxx"); - assert_eq!(&line_display_text("ab\t\t", 0, None), "ab"); - assert_eq!(&line_display_text("ab\t\t", 4, None), "ab "); - assert_eq!(&line_display_text("ab\t\t", 8, None), "ab "); - assert_eq!(&line_display_text("abcd\t", 4, None), "abcd "); - assert_eq!(&line_display_text( "あ\t", 0, None), "あ"); - assert_eq!(&line_display_text( "あ\t", 4, None), "あ "); - assert_eq!(&line_display_text( "🐶\t", 4, None), "🐶 "); - assert_eq!(&line_display_text( "あ\t", 4, Some('x')), "xx"); + assert_eq!(&build( "", 0, None), ""); + assert_eq!(&build( "", 4, None), ""); + assert_eq!(&build( "", 8, None), ""); + assert_eq!(&build( "", 0, Some('x')), ""); + assert_eq!(&build( "", 4, Some('x')), ""); + assert_eq!(&build( "", 8, Some('x')), ""); + assert_eq!(&build( "a", 0, None), "a"); + assert_eq!(&build( "a", 4, None), "a"); + assert_eq!(&build( "a", 8, None), "a"); + assert_eq!(&build( "a", 0, Some('x')), "x"); + assert_eq!(&build( "a", 4, Some('x')), "x"); + assert_eq!(&build( "a", 8, Some('x')), "x"); + assert_eq!(&build( "a\t", 0, None), "a"); + assert_eq!(&build( "a\t", 4, None), "a "); + assert_eq!(&build( "a\t", 8, None), "a "); + assert_eq!(&build( "a\t", 0, Some('x')), "xx"); + assert_eq!(&build( "a\t", 4, Some('x')), "xx"); + assert_eq!(&build( "a\t", 8, Some('x')), "xx"); + assert_eq!(&build( "\t", 0, None), "\t"); + assert_eq!(&build( "\t", 4, None), " "); + assert_eq!(&build( "\t", 8, None), " "); + assert_eq!(&build( "\t", 0, Some('x')), "x"); + assert_eq!(&build( "\t", 4, Some('x')), "x"); + assert_eq!(&build( "\t", 8, Some('x')), "x"); + assert_eq!(&build( "a\tb", 0, None), "ab"); + assert_eq!(&build( "a\tb", 4, None), "a b"); + assert_eq!(&build( "a\tb", 8, None), "a b"); + assert_eq!(&build( "a\tb", 0, Some('x')), "xxx"); + assert_eq!(&build( "a\tb", 4, Some('x')), "xxx"); + assert_eq!(&build( "a\tb", 8, Some('x')), "xxx"); + assert_eq!(&build("a\t\tb", 0, None), "ab"); + assert_eq!(&build("a\t\tb", 4, None), "a b"); + assert_eq!(&build("a\t\tb", 8, None), "a b"); + assert_eq!(&build("a\t\tb", 0, Some('x')), "xxxx"); + assert_eq!(&build("a\t\tb", 4, Some('x')), "xxxx"); + assert_eq!(&build("a\t\tb", 8, Some('x')), "xxxx"); + assert_eq!(&build("a\tb\tc", 0, None), "abc"); + assert_eq!(&build("a\tb\tc", 4, None), "a b c"); + assert_eq!(&build("a\tb\tc", 8, None), "a b c"); + assert_eq!(&build("a\tb\tc", 0, Some('x')), "xxxxx"); + assert_eq!(&build("a\tb\tc", 4, Some('x')), "xxxxx"); + assert_eq!(&build("a\tb\tc", 8, Some('x')), "xxxxx"); + assert_eq!(&build("ab\t\t", 0, None), "ab"); + assert_eq!(&build("ab\t\t", 4, None), "ab "); + assert_eq!(&build("ab\t\t", 8, None), "ab "); + assert_eq!(&build("abcd\t", 4, None), "abcd "); + assert_eq!(&build( "あ\t", 0, None), "あ"); + assert_eq!(&build( "あ\t", 4, None), "あ "); + assert_eq!(&build( "🐶\t", 4, None), "🐶 "); + assert_eq!(&build( "あ\t", 4, Some('x')), "xx"); + + // When the start position of the text is not start of the line (#43) + assert_eq!(build_with_offset(1, "", 0), ( "".into(), 1)); + assert_eq!(build_with_offset(1, "a", 0), ( "a".into(), 2)); + assert_eq!(build_with_offset(1, "あ", 0), ( "あ".into(), 3)); + assert_eq!(build_with_offset(1, "\t", 4), ( " ".into(), 4)); + assert_eq!(build_with_offset(1, "a\t", 4), ( "a ".into(), 4)); + assert_eq!(build_with_offset(1, "あ\t", 4), ( "あ ".into(), 4)); + assert_eq!(build_with_offset(2, "\t", 4), ( " ".into(), 4)); + assert_eq!(build_with_offset(2, "a\t", 4), ( "a ".into(), 4)); + assert_eq!(build_with_offset(2, "あ\t", 4), ( "あ ".into(), 8)); + assert_eq!(build_with_offset(3, "a\t", 4), ( "a ".into(), 8)); + assert_eq!(build_with_offset(4, "\t", 4), ( " ".into(), 8)); + assert_eq!(build_with_offset(4, "a\t", 4), ( "a ".into(), 8)); + assert_eq!(build_with_offset(4, "あ\t", 4), ( "あ ".into(), 8)); + assert_eq!(build_with_offset(5, "\t", 4), ( " ".into(), 8)); + assert_eq!(build_with_offset(5, "a\t", 4), ( "a ".into(), 8)); + assert_eq!(build_with_offset(5, "あ\t", 4), ( "あ ".into(), 8)); + assert_eq!(build_with_offset(2, "\t\t", 4), ( " ".into(), 8)); + assert_eq!(build_with_offset(2, "a\ta\t", 4), ( "a a ".into(), 8)); + assert_eq!(build_with_offset(1, "あ\tあ\t", 4), ( "あ あ ".into(), 8)); + assert_eq!(build_with_offset(2, "あ\tあ\t", 4), ("あ あ ".into(), 12)); } + + // TODO: Add tests for LineHighlighter }