feat(debug): highlight current line (#5957)

Add new theme highlight keys, for setting the colour of the breakpoint
character and the current line at which execution has been paused at.
The two new keys are `ui.highlight.frameline` and `ui.debug.breakpoint`.
Highlight according to those keys, both the line at which debugging
is paused at and the breakpoint indicator.

Add an indicator for the current line at which execution is paused
at, themed by the `ui.debug.active` theme scope. Update various themes
to showcase how the new functionality works.

Better icons are dependent on #2869, and as such will be handled in the
future, once it lands.

Closes: #5952

Signed-off-by: Filip Dutescu <filip.dutescu@gmail.com>

1 files changed, 18 insertions, 34 deletions

diff --git a/helix-term/src/ui/editor.rs b/helix-term/src/ui/editor.rs
index 4cac0fa8..d4b141a0 100644
--- a/helix-term/src/ui/editor.rs
+++ b/helix-term/src/ui/editor.rs
@@ -93,40 +93,6 @@ impl EditorView {
         let mut line_decorations: Vec<Box<dyn LineDecoration>> = Vec::new();
         let mut translated_positions: Vec<TranslatedPosition> = Vec::new();
 
-        // DAP: Highlight current stack frame position
-        let stack_frame = editor.debugger.as_ref().and_then(|debugger| {
-            if let (Some(frame), Some(thread_id)) = (debugger.active_frame, debugger.thread_id) {
-                debugger
-                    .stack_frames
-                    .get(&thread_id)
-                    .and_then(|bt| bt.get(frame))
-            } else {
-                None
-            }
-        });
-        if let Some(frame) = stack_frame {
-            if doc.path().is_some()
-                && frame
-                    .source
-                    .as_ref()
-                    .and_then(|source| source.path.as_ref())
-                    == doc.path()
-            {
-                let line = frame.line - 1; // convert to 0-indexing
-                let style = theme.get("ui.highlight");
-                let line_decoration = move |renderer: &mut TextRenderer, pos: LinePos| {
-                    if pos.doc_line != line {
-                        return;
-                    }
-                    renderer
-                        .surface
-                        .set_style(Rect::new(area.x, pos.visual_line, area.width, 1), style);
-                };
-
-                line_decorations.push(Box::new(line_decoration));
-            }
-        }
-
         if is_focused && config.cursorline {
             line_decorations.push(Self::cursorline_decorator(doc, view, theme))
         }
@@ -135,6 +101,23 @@ impl EditorView {
             Self::highlight_cursorcolumn(doc, view, surface, theme, inner, &text_annotations);
         }
 
+        // Set DAP highlights, if needed.
+        if let Some(frame) = editor.current_stack_frame() {
+            let dap_line = frame.line.saturating_sub(1) as usize;
+            let style = theme.get("ui.highlight.frameline");
+            let line_decoration = move |renderer: &mut TextRenderer, pos: LinePos| {
+                if pos.doc_line != dap_line {
+                    return;
+                }
+                renderer.surface.set_style(
+                    Rect::new(inner.x, inner.y + pos.visual_line, inner.width, 1),
+                    style,
+                );
+            };
+
+            line_decorations.push(Box::new(line_decoration));
+        }
+
         let mut highlights =
             Self::doc_syntax_highlights(doc, view.offset.anchor, inner.height, theme);
         let overlay_highlights = Self::overlay_syntax_highlights(
@@ -422,6 +405,7 @@ impl EditorView {
         let primary_selection_scope = theme
             .find_scope_index_exact("ui.selection.primary")
             .unwrap_or(selection_scope);
+
         let base_cursor_scope = theme
             .find_scope_index_exact("ui.cursor")
             .unwrap_or(selection_scope);