@@ -4,13 +4,16 @@ use crossterm::{
44 execute, queue,
55 style::{
66 Attribute as CAttribute, Color as CColor, Print, SetAttribute, SetBackgroundColor,
7− SetForegroundColor, SetUnderlineColor,
7+ SetForegroundColor,
88 },
99 terminal::{self, Clear, ClearType},
10+ Command,
1011};
1112use helix_view::graphics::{Color, CursorKind, Modifier, Rect, UnderlineStyle};
12−use std::io::{self, Write};
13−
13+use std::{
14+ fmt,
15+ io::{self, Write},
16+};
1417fn vte_version() -> Option<usize> {
1518 std::env::var("VTE_VERSION").ok()?.parse().ok()
1619}
@@ -108,18 +111,19 @@ where
108111 map_error(queue!(self.buffer, SetBackgroundColor(color)))?;
109112 bg = cell.bg;
110113 }
111− if cell.underline_color != underline_color {
112− let color = CColor::from(cell.underline_color);
113− map_error(queue!(self.buffer, SetUnderlineColor(color)))?;
114− underline_color = cell.underline_color;
115− }
116114
117115 let mut new_underline_style = cell.underline_style;
118116 if !self.capabilities.has_extended_underlines {
119117 match new_underline_style {
120− UnderlineStyle::Reset => (),
118+ UnderlineStyle::Reset | UnderlineStyle::Line => (),
121119 _ => new_underline_style = UnderlineStyle::Line,
122120 }
121+
122+ if cell.underline_color != underline_color {
123+ let color = CColor::from(cell.underline_color);
124+ map_error(queue!(self.buffer, SetUnderlineColor(color)))?;
125+ underline_color = cell.underline_color;
126+ }
123127 }
124128
125129 if new_underline_style != underline_style {
@@ -244,3 +248,58 @@ impl ModifierDiff {
244248 Ok(())
245249 }
246250}
251+
252+/// Crossterm uses semicolon as a seperator for colors
253+/// this is actually not spec compliant (altough commonly supported)
254+/// However the correct approach is to use colons as a seperator.
255+/// This usually doesn't make a difference for emulators that do support colored underlines.
256+/// However terminals that do not support colored underlines will ignore underlines colors with colons
257+/// while escape sequences with semicolons are always processed which leads to weird visual artifacts.
258+/// See [this nvim issue](https://github.com/neovim/neovim/issues/9270) for details
259+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
260+pub struct SetUnderlineColor(pub CColor);
261+
262+impl Command for SetUnderlineColor {
263+ fn write_ansi(&self, f: &mut impl fmt::Write) -> fmt::Result {
264+ let color = self.0;
265+
266+ if color == CColor::Reset {
267+ write!(f, "\x1b[59m")?;
268+ return Ok(());
269+ }
270+ f.write_str("\x1b[58:")?;
271+
272+ let res = match color {
273+ CColor::Black => f.write_str("5:0"),
274+ CColor::DarkGrey => f.write_str("5:8"),
275+ CColor::Red => f.write_str("5:9"),
276+ CColor::DarkRed => f.write_str("5:1"),
277+ CColor::Green => f.write_str("5:10"),
278+ CColor::DarkGreen => f.write_str("5:2"),
279+ CColor::Yellow => f.write_str("5:11"),
280+ CColor::DarkYellow => f.write_str("5:3"),
281+ CColor::Blue => f.write_str("5:12"),
282+ CColor::DarkBlue => f.write_str("5:4"),
283+ CColor::Magenta => f.write_str("5:13"),
284+ CColor::DarkMagenta => f.write_str("5:5"),
285+ CColor::Cyan => f.write_str("5:14"),
286+ CColor::DarkCyan => f.write_str("5:6"),
287+ CColor::White => f.write_str("5:15"),
288+ CColor::Grey => f.write_str("5:7"),
289+ CColor::Rgb { r, g, b } => write!(f, "2::{}:{}:{}", r, g, b),
290+ CColor::AnsiValue(val) => write!(f, "5:{}", val),
291+ _ => Ok(()),
292+ };
293+ res?;
294+ write!(f, "m")?;
295+ Ok(())
296+ }
297+
298+ #[cfg(windows)]
299+ fn execute_winapi(&self) -> crossterm::Result<()> {
300+ Err(std::io::Error::new(
301+ std::io::ErrorKind::Other,
302+ "SetUnderlineColor not supported by winapi.",
303+ ))
304+ }
305+}