termwiz: add ClearLine change (#8124)

termwiz/src/render/terminfo.rs

@@ -385,6 +385,19 @@ impl TerminfoRenderer {
                         out.write_all(buf.as_slice())?;
                     }
                 }
+                Change::ClearLine(color) => {
+                    let defaults = CellAttributes::default().set_background(*color).clone();
+                    if self.current_attr != defaults {
+                        self.pending_attr = Some(defaults);
+                        self.flush_pending_attr(out)?;
+                    }
+                    self.pending_attr = None;
+                    write!(
+                        out,
+                        "{}",
+                        CSI::Edit(Edit::EraseInLine(EraseInLine::EraseLine))
+                    )?;
+                }
                 Change::ClearToEndOfLine(color) => {
                     // ClearScreen implicitly resets all to default
                     let defaults = CellAttributes::default().set_background(*color).clone();
@@ -1012,6 +1025,27 @@ mod test {
         assert_eq!(out.renderer.current_attr, CellAttributes::default());
     }
 
+    #[test]
+    fn clear_line() {
+        let mut out = FakeTerm::new(xterm_terminfo());
+        out.render(&[Change::ClearLine(AnsiColor::Maroon.into())])
+            .unwrap();
+
+        assert_eq!(
+            out.parse(),
+            vec![
+                Action::CSI(CSI::Sgr(Sgr::Background(AnsiColor::Maroon.into()))),
+                Action::CSI(CSI::Edit(Edit::EraseInLine(EraseInLine::EraseLine))),
+            ]
+        );
+        assert_eq!(
+            out.renderer.current_attr,
+            CellAttributes::default()
+                .set_background(AnsiColor::Maroon)
+                .clone()
+        );
+    }
+
     #[test]
     fn clear_screen_bce() {
         let mut out = FakeTerm::new_with_size(xterm_terminfo(), 4, 3);

termwiz/src/render/windows.rs

@@ -328,6 +328,19 @@ impl WindowsConsoleRenderer {
                     );
                     buffer.set_cursor(0, 0, out)?;
                 }
+                Change::ClearLine(color) => {
+                    let attr = CellAttributes::default()
+                        .set_background(color.clone())
+                        .clone();
+
+                    buffer.fill(
+                        ' ',
+                        to_attr_word(&self.capabilities, &attr),
+                        0,
+                        buffer.cursor_y,
+                        cols,
+                    );
+                }
                 Change::ClearToEndOfLine(color) => {
                     let attr = CellAttributes::default()
                         .set_background(color.clone())

wezterm-surface/src/change.rs

@@ -45,6 +45,9 @@ pub enum Change {
     /// Implicitly clears all attributes prior to clearing the screen.
     /// Moves the cursor to the home position (top left).
     ClearScreen(ColorAttribute),
+    /// Clear the entire current line.  The background color is set to the
+    /// provided color.  The cursor position remains unchanged.
+    ClearLine(ColorAttribute),
     /// Clear from the current cursor X position to the rightmost
     /// edge of the screen.  The background color is set to the
     /// provided color.  The cursor position remains unchanged.
@@ -218,6 +221,7 @@ impl ChangeSequence {
             | Change::CursorColor(_)
             | Change::CursorShape(_)
             | Change::CursorVisibility(_)
+            | Change::ClearLine(_)
             | Change::ClearToEndOfLine(_)
             | Change::Title(_)
             | Change::LineAttribute(_)

wezterm-surface/src/lib.rs

@@ -305,6 +305,7 @@ impl Surface {
             Change::Attribute(change) => self.attributes.apply_change(change),
             Change::CursorPosition { x, y } => self.set_cursor_pos(x, y),
             Change::ClearScreen(color) => self.clear_screen(*color),
+            Change::ClearLine(color) => self.clear_line(*color),
             Change::ClearToEndOfLine(color) => self.clear_eol(*color),
             Change::ClearToEndOfScreen(color) => self.clear_eos(*color),
             Change::CursorColor(color) => self.cursor_color = *color,
@@ -401,6 +402,12 @@ impl Surface {
         self.lines[self.ypos].fill_range(self.xpos..self.width, &cleared, self.seqno);
     }
 
+    fn clear_line(&mut self, color: ColorAttribute) {
+        self.attributes = CellAttributes::default().set_background(color).clone();
+        let cleared = Cell::new(' ', self.attributes.clone());
+        self.lines[self.ypos].fill_range(0..self.width, &cleared, self.seqno);
+    }
+
     fn scroll_screen_up(&mut self) {
         self.lines.remove(0);
         self.lines.push(Line::with_width(self.width, self.seqno));
@@ -1015,6 +1022,25 @@ mod test {
         assert_eq!(s.screen_chars_to_string(), "   \nw\nfoo\n");
     }
 
+    #[test]
+    fn clear_line() {
+        let mut s = Surface::new(3, 3);
+        s.add_change("helwowfoo");
+        s.add_change(Change::CursorPosition {
+            x: Position::Absolute(1),
+            y: Position::Absolute(1),
+        });
+        s.add_change(Change::ClearLine(AnsiColor::Maroon.into()));
+
+        assert_eq!(s.xpos, 1);
+        assert_eq!(s.ypos, 1);
+        assert_eq!(s.screen_chars_to_string(), "hel\n   \nfoo\n");
+        assert_eq!(
+            s.lines[1].get_cell(0).unwrap().attrs().background(),
+            ColorAttribute::PaletteIndex(1)
+        );
+    }
+
     #[test]
     fn clear_eos() {
         let mut s = Surface::new(3, 3);