From 8234fcdeb201c524deaf4bbf557e093495f5a5e3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=9B=B7=E7=94=B5=E8=8A=BD=E8=A1=A3?=
 <zhangyanghaha0407@outlook.com>
Date: Mon, 12 Oct 2026 11:15:52 -0400
Subject: [PATCH] typography and documents: an exported formula frames its
 outlined text; rendered modes have no source selection

---
 src/documents/document/place.rs       |  4 ++++
 src/documents/document/tests/place.rs | 12 ++++++++----
 src/typography/math.rs                | 17 ++++++++++++-----
 src/typography/math/tests.rs          | 18 ++++++++++++++++++
 4 files changed, 42 insertions(+), 9 deletions(-)

diff --git a/src/documents/document/place.rs b/src/documents/document/place.rs
index 4ba8935..3cdb5ad 100644
--- a/src/documents/document/place.rs
+++ b/src/documents/document/place.rs
@@ -31,6 +31,10 @@ impl MarkdownDocument {
     /// The selected Markdown: the source's, or the open block's.
     pub fn selected(&self, cx: &App) -> String {
         let Some(open) = &self.open else {
+            // Rendered modes show no source selection.
+            if !matches!(self.mode, MarkdownMode::Source | MarkdownMode::Split) {
+                return String::new();
+            }
             let editor = self.editor.read(cx);
             return editor.text()[editor.primary().range()].to_string();
         };
diff --git a/src/documents/document/tests/place.rs b/src/documents/document/tests/place.rs
index cdbddc8..965f39d 100644
--- a/src/documents/document/tests/place.rs
+++ b/src/documents/document/tests/place.rs
@@ -211,10 +211,14 @@ fn the_selection_reads_in_source_and_in_an_open_block(cx: &mut TestAppContext) {
         document.read_with(cx, |document, cx| document.selected(cx)),
         "One"
     );
-    document.update_in(cx, |document, window, cx| {
-        document.set_mode(MarkdownMode::Visual, window, cx)
-    });
-    frames(cx);
+    for mode in [MarkdownMode::Preview, MarkdownMode::Visual] {
+        document.update_in(cx, |document, window, cx| {
+            document.set_mode(mode, window, cx)
+        });
+        frames(cx);
+        let selected = document.read_with(cx, |document, cx| document.selected(cx));
+        assert_eq!(selected, "", "{mode:?} shows no source selection");
+    }
     super::type_in(&document, Some(1), None, cx);
     document.update(cx, |document, cx| {
         let open = document.open.as_ref().expect("a block is open");
diff --git a/src/typography/math.rs b/src/typography/math.rs
index f3db1e0..87bf6ed 100644
--- a/src/typography/math.rs
+++ b/src/typography/math.rs
@@ -125,13 +125,20 @@ pub fn formula_svg(source: &str, display: bool) -> Result<String, MathError> {
         font: 1600,
         scale: 100,
     };
+    let (svg, width, height) = laid(&formula)?;
     // RaTeX writes text where it has no outline.
-    let (svg, _) = svg(&formula)?;
-    crate::documents::flatten(&svg).map_err(MathError::said)
+    let outlined = crate::documents::flatten(&svg).map_err(MathError::said)?;
+    framed(&outlined, width, height).map(|(svg, _)| svg)
 }
 
 /// The formula as outlined SVG holding all ink; its size.
 fn svg(formula: &Formula) -> Result<(String, Size<Pixels>), MathError> {
+    let (svg, width, height) = laid(formula)?;
+    framed(&svg, width, height)
+}
+
+/// RaTeX's SVG and the layout box's width and height.
+fn laid(formula: &Formula) -> Result<(String, f32, f32), MathError> {
     let ast = parsed(&formula.source)?;
     let [r, g, b, a] = formula
         .rgba
@@ -144,7 +151,7 @@ fn svg(formula: &Formula) -> Result<(String, Size<Pixels>), MathError> {
         })
         .with_color(Color::new(r, g, b, a));
     let font = f64::from(formula.font) / 100.0;
-    let laid = guarded(|| {
+    let typeset = guarded(|| {
         let list = to_display_list(&layout(&ast, &options));
         let svg = render_to_svg(
             &list,
@@ -158,8 +165,8 @@ fn svg(formula: &Formula) -> Result<(String, Size<Pixels>), MathError> {
         );
         (list.width * font, (list.height + list.depth) * font, svg)
     })?;
-    let (width, height, svg) = laid;
-    framed(&svg, width as f32, height as f32)
+    let (width, height, svg) = typeset;
+    Ok((svg, width as f32, height as f32))
 }
 
 /// Runs RaTeX's layout; a panic becomes an error.
diff --git a/src/typography/math/tests.rs b/src/typography/math/tests.rs
index e408244..b874a29 100644
--- a/src/typography/math/tests.rs
+++ b/src/typography/math/tests.rs
@@ -193,3 +193,21 @@ fn an_exported_formula_outlines_its_text_or_says_why() {
     let why = formula_svg("\\text{\u{F0000}}", false).expect_err("no font");
     assert!(why.to_string().contains("font"), "{why}");
 }
+
+#[test]
+fn an_exported_formula_frames_its_outlined_text() {
+    // Wide or tall faces from the system, where fonts have them.
+    for source in [r"\text{한글}", r"\text{𓀀} + x"] {
+        let Ok(svg) = formula_svg(source, false) else {
+            continue;
+        };
+        let tree =
+            usvg::Tree::from_data(svg.as_bytes(), &usvg::Options::default()).expect("parses");
+        let (ink, shape) = (tree.root().abs_stroke_bounding_box(), tree.size());
+        let inside = ink.left() >= -0.01
+            && ink.top() >= -0.01
+            && ink.right() <= shape.width() + 0.01
+            && ink.bottom() <= shape.height() + 0.01;
+        assert!(inside, "{source}: {ink:?} in {shape:?}");
+    }
+}