Documents: an open heading keeps its weight and color; front matter keeps its panel

The field's highlighter gave headings and bold semibold over the drawn
bold, and its plain color hid a sixth-level heading's muted color. It
now uses the drawn weight, and runs inside a sixth-level heading stay
muted. Front matter opens in its mono, muted panel. The open text box
is built by one function, so tests read its background directly.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/documents/document/look.rs

@@ -90,7 +90,7 @@ impl MarkdownDocument {
             block.size.height -= self.room;
         }
         let view = self.list.viewport_bounds();
-        // A new layout, a resize or the ends' room moves it.
+        // New layout, resize or end room moves it.
         let heights = [block.size.height, view.size.height, self.room]
             .map(|height| f32::from(height).round() as u64);
         let moved = (ix, self.edits, self.typed, heights);

src/documents/document/tests/mod.rs

@@ -210,8 +210,10 @@ fn the_source_colors_markdown(cx: &mut TestAppContext) {
         document.editor().read(cx).line_colors("a **b**", cx)
     });
     assert!(
-        colors.iter().any(|(range, style)| *range == (2..7)
+        colors
-            && style.font_weight == Some(gpui::FontWeight::SEMIBOLD)),
+            .iter()
+            .any(|(range, style)| *range == (2..7)
+                && style.font_weight == Some(gpui::FontWeight::BOLD)),
         "{colors:?}"
     );
 }

src/documents/document/tests/open_look.rs

@@ -1,9 +1,17 @@
 //! An open block keeps its place and size (R7.5).
 
-use gpui::{Bounds, Modifiers, Pixels, TestAppContext, VisualTestContext, rems};
+use gpui::{
+    Bounds, Fill, Modifiers, Pixels, StyleRefinement, Styled, TestAppContext, VisualTestContext,
+    rems,
+};
 
 use super::{open, press};
-use crate::documents::MarkdownMode;
+use crate::documents::{TargetBlock, document::visual::open_text};
+use crate::{
+    documents::{MarkdownMode, markdown_highlights, render::HEAVY},
+    forms::Highlight,
+    theme::ActiveTheme,
+};
 
 /// Block 0's bounds closed, then open.
 fn closed_then_open<'a>(
@@ -50,7 +58,17 @@ fn an_open_heading_keeps_its_size(cx: &mut TestAppContext) {
 
 #[gpui::test]
 fn an_open_code_block_keeps_its_panel(cx: &mut TestAppContext) {
-    let (closed, open, cx) = closed_then_open("```\nlet x = 1;\n```\n", cx);
+    keeps_its_panel("```\nlet x = 1;\n```\n", cx);
+}
+
+#[gpui::test]
+fn open_front_matter_keeps_its_panel(cx: &mut TestAppContext) {
+    keeps_its_panel("---\nkey: value\n---\n\nText.\n", cx);
+}
+
+/// Block 0 opens in place, its panel at the closed inset.
+fn keeps_its_panel(source: &str, cx: &mut TestAppContext) {
+    let (closed, open, cx) = closed_then_open(source, cx);
     assert!(
         near(closed.top(), open.top()) && near(closed.left(), open.left()),
         "{closed:?} {open:?}"
@@ -71,3 +89,100 @@ fn an_open_code_block_keeps_its_panel(cx: &mut TestAppContext) {
         "{panel:?} {closed:?}"
     );
 }
+
+/// The highlight on the run that holds `word`.
+fn run(source: &str, word: &str, cx: &mut TestAppContext) -> Highlight {
+    cx.update(crate::init_for_tests);
+    let at = source.find(word).expect("the word");
+    cx.update(|cx| {
+        markdown_highlights(source, cx)
+            .into_iter()
+            .rfind(|(range, _)| range.start <= at && at < range.end)
+            .expect("a run")
+            .1
+    })
+}
+
+#[gpui::test]
+fn an_open_heading_keeps_its_weight(cx: &mut TestAppContext) {
+    for source in [
+        "# Heavy words
+",
+        "a **Heavy** b
+",
+    ] {
+        assert_eq!(run(source, "Heavy", cx).weight, Some(HEAVY), "{source}");
+    }
+}
+
+#[gpui::test]
+fn an_open_sixth_heading_stays_muted(cx: &mut TestAppContext) {
+    let muted = cx.update(|cx| {
+        crate::init_for_tests(cx);
+        cx.theme().colors.fg_muted
+    });
+    for word in ["Quiet", "Loud"] {
+        let source = "###### Quiet **Loud**
+";
+        assert_eq!(run(source, word, cx).color, muted, "{word}");
+    }
+    let fg = cx.update(|cx| cx.theme().colors.fg);
+    assert_eq!(
+        run(
+            "##### Plain
+",
+            "Plain",
+            cx
+        )
+        .color,
+        fg
+    );
+}
+
+/// The open text box's style for `kind`.
+fn styled(kind: TargetBlock, cx: &mut TestAppContext) -> StyleRefinement {
+    cx.update(crate::init_for_tests);
+    cx.update(|cx| {
+        open_text(Some((kind, true)), 1.0, cx.theme())
+            .style()
+            .clone()
+    })
+}
+
+#[gpui::test]
+fn open_prose_has_no_panel(cx: &mut TestAppContext) {
+    for kind in [
+        TargetBlock::Paragraph,
+        TargetBlock::Heading(2),
+        TargetBlock::List,
+        TargetBlock::Quote,
+    ] {
+        assert_eq!(styled(kind, cx).background, None, "{kind:?}");
+    }
+}
+
+#[gpui::test]
+fn open_code_math_and_front_matter_keep_their_panel(cx: &mut TestAppContext) {
+    let (sunken, muted, mono) = cx.update(|cx| {
+        crate::init_for_tests(cx);
+        let theme = cx.theme();
+        (
+            theme.colors.sunken,
+            theme.colors.fg_muted,
+            theme.mono_family.clone(),
+        )
+    });
+    for kind in [
+        TargetBlock::Code,
+        TargetBlock::Math,
+        TargetBlock::FrontMatter,
+    ] {
+        assert_eq!(
+            styled(kind, cx).background,
+            Some(Fill::from(sunken)),
+            "{kind:?}"
+        );
+    }
+    let front = styled(TargetBlock::FrontMatter, cx).text;
+    assert_eq!((front.color, front.font_family), (Some(muted), Some(mono)));
+}

src/documents/document/visual.rs

@@ -1,5 +1,5 @@
 use gpui::{
-    AnyElement, App, ClickEvent, Context, ExternalPaths, FontWeight, InteractiveElement,
+    AnyElement, App, ClickEvent, Context, Div, ExternalPaths, FontWeight, InteractiveElement,
     IntoElement, KeyBinding, MouseButton, MouseDownEvent, ParentElement, Render,
     StatefulInteractiveElement, Styled, StyledText, Window, actions, div, list,
     prelude::FluentBuilder as _, relative,
@@ -13,7 +13,7 @@ use crate::{
     },
     forms::{self, Down, Up},
     primitives::FocusRing as _,
-    theme::{ActiveTheme, Radius, TextSize},
+    theme::{ActiveTheme, Radius, TextSize, Theme},
 };
 
 actions!(markdown_document, [Undo, Redo, Indent, Outdent, Paste]);
@@ -23,6 +23,44 @@ const CONTEXT: &str = "MarkdownDocument";
 /// How far a faded block recedes.
 const FADED: f32 = 0.35;
 
+/// The open block's text box: its closed font and panel.
+pub(super) fn open_text(kind: Option<(TargetBlock, bool)>, scale: f32, theme: &Theme) -> Div {
+    let colors = &theme.colors;
+    let body = theme.text_size(TextSize::Base) * scale;
+    let mono = theme.text_size(TextSize::Sm) * scale;
+    let text = div()
+        .debug_selector(|| "markdown-open-text".to_string())
+        .text_size(body)
+        .line_height(body * 1.6)
+        .text_color(colors.fg);
+    match kind {
+        Some((TargetBlock::Heading(level), true)) => text
+            .pt_2()
+            .text_size(body * heading_step(level))
+            .line_height(relative(1.3))
+            .font_weight(HEAVY)
+            .when(level == 6, |text| text.text_color(colors.fg_muted)),
+        // Code, math and front matter keep their panel.
+        Some((kind @ (TargetBlock::Code | TargetBlock::Math | TargetBlock::FrontMatter), true)) => {
+            text.p_3()
+                .rounded(theme.radius(Radius::Md))
+                .bg(colors.sunken)
+                .when(kind != TargetBlock::Math, |text| {
+                    text.font_family(theme.mono_family.clone()).text_size(mono)
+                })
+                .when(kind == TargetBlock::FrontMatter, |text| {
+                    text.text_color(colors.fg_muted)
+                })
+        }
+        // Written as is: mono and muted.
+        Some((_, false)) => text
+            .font_family(theme.mono_family.clone())
+            .line_height(gpui::phi())
+            .text_color(colors.fg_muted),
+        _ => text,
+    }
+}
+
 /// Modes with a reader's block to keep.
 fn editing_mode(mode: MarkdownMode) -> bool {
     mode == MarkdownMode::Visual
@@ -163,37 +201,8 @@ impl MarkdownDocument {
         cx: &mut Context<Self>,
     ) -> AnyElement {
         let point = Self::point_in_open(cx);
-        let theme = cx.theme();
+        let kind = block.map(|block| (block.kind, block.nodes.is_some()));
-        let colors = theme.colors.clone();
+        let text = open_text(kind, self.look.scale, cx.theme());
-        let body = theme.text_size(TextSize::Base) * self.look.scale;
-        let text = div()
-            .debug_selector(|| "markdown-open-text".to_string())
-            .text_size(body)
-            .line_height(body * 1.6)
-            .text_color(colors.fg);
-        let text = match block.map(|block| (block.kind, block.nodes.is_some())) {
-            Some((TargetBlock::Heading(level), true)) => text
-                .pt_2()
-                .text_size(body * heading_step(level))
-                .line_height(relative(1.3))
-                .font_weight(HEAVY)
-                .when(level == 6, |text| text.text_color(colors.fg_muted)),
-            // Code and math keep their panel.
-            Some((kind @ (TargetBlock::Code | TargetBlock::Math), true)) => text
-                .p_3()
-                .rounded(theme.radius(Radius::Md))
-                .bg(colors.sunken)
-                .when(kind == TargetBlock::Code, |text| {
-                    text.font_family(theme.mono_family.clone())
-                        .text_size(theme.text_size(TextSize::Sm) * self.look.scale)
-                }),
-            // Written as is: mono and muted.
-            Some((_, false)) => text
-                .font_family(theme.mono_family.clone())
-                .line_height(gpui::phi())
-                .text_color(colors.fg_muted),
-            _ => text,
-        };
         div()
             .debug_selector(|| "markdown-open".to_string())
             .on_mouse_down(MouseButton::Right, point)

src/documents/markdown.rs

@@ -1,10 +1,10 @@
 use std::ops::Range;
 
-use gpui::{App, FontWeight};
+use gpui::App;
 use markdown::{Constructs, ParseOptions, mdast};
 use unicode_segmentation::UnicodeSegmentation;
 
-use crate::{forms::Highlight, theme::ActiveTheme};
+use crate::{documents::render::HEAVY, forms::Highlight, theme::ActiveTheme};
 
 /// GitHub's flavor, and math between dollars.
 pub(crate) fn options() -> ParseOptions {
@@ -141,10 +141,22 @@ pub fn marks(text: &str) -> Vec<(Range<usize>, Mark)> {
 /// Markdown styled as typed; its syntax recedes.
 pub fn markdown_highlights(text: &str, cx: &App) -> Vec<(Range<usize>, Highlight)> {
     let colors = &cx.theme().colors;
-    let plain = Highlight::new(colors.fg);
+    let marks = marks(text);
-    marks(text)
+    // A sixth-level heading reads muted, as drawn.
+    let muted: Vec<Range<usize>> = marks
+        .iter()
+        .filter(|(_, mark)| *mark == Mark::Heading(6))
+        .map(|(range, _)| range.clone())
+        .collect();
+    marks
         .into_iter()
         .map(|(range, mark)| {
+            let within =
+                |outer: &Range<usize>| outer.start <= range.start && range.end <= outer.end;
+            let plain = Highlight::new(match muted.iter().any(within) {
+                true => colors.fg_muted,
+                false => colors.fg,
+            });
             let range = match mark {
                 Mark::Strike => {
                     let span = &text[range.clone()];
@@ -155,7 +167,7 @@ pub fn markdown_highlights(text: &str, cx: &App) -> Vec<(Range<usize>, Highlight
             };
             let highlight = match mark {
                 Mark::Strong | Mark::Heading(_) => Highlight {
-                    weight: Some(FontWeight::SEMIBOLD),
+                    weight: Some(HEAVY),
                     ..plain
                 },
                 Mark::Emphasis => Highlight {