fix(layout): find comment anchors in one pass over a paragraph's objects

crates/formats/src/markdown/blocks.rs

@@ -474,17 +474,14 @@ fn parse_blocks(lines: &[String], depth: usize, level: u8, refs: &Refs) -> Vec<F
                     let p = Para { align: a, inlines: parse_inlines(s, &Fmt::default(), depth, refs), ..Default::default() };
                     Cell { blocks: vec![FBlock::Para(p)], header, ..Default::default() }
                 };
-                // A document row keeps MAX_COLS cells: only those are built, so a wide header
-                // doesn't pad every sparse row below it out to its width.
-                let cols = aligns.len().min(wordcraft_doc::table::MAX_COLS);
-                table.rows.push(head.iter().zip(&aligns).take(cols).map(|(s, a)| cell(s, true, *a)).collect());
+                table.rows.push(head.iter().zip(&aligns).map(|(s, a)| cell(s, true, *a)).collect());
                 i += 2;
                 while let Some(l) = lines.get(i) {
                     if is_blank(l) || !l.contains('|') || interrupts(l) {
                         break;
                     }
                     let mut cells = split_row(l);
-                    cells.resize(cols, String::new());
+                    cells.resize(aligns.len(), String::new());
                     table.rows.push(cells.iter().zip(&aligns).map(|(s, a)| cell(s, false, *a)).collect());
                     i += 1;
                 }

crates/formats/src/markdown/tests.rs

@@ -714,17 +714,3 @@ fn exported_link_destinations_read_back_unchanged() {
     assert_eq!(md("https://example.com/a b"), "[x](<https://example.com/a b>)");
     assert_eq!(md("https://e.com/x\ny"), "[x](https://e.com/xy)");
 }
-
-#[test]
-fn a_wide_table_builds_only_the_cells_a_row_keeps() {
-    // A 5,000-column header padded every one-cell row below it to 5,000 cells.
-    let n = 5000;
-    let md = format!("{}|\n{}|\n{}", "|h".repeat(n), "|-".repeat(n), "|x|\n".repeat(200));
-    let flow = parse(&md);
-    let FBlock::Table(t) = &flow.blocks[0] else { panic!("expected table") };
-    assert_eq!(t.rows.len(), 201);
-    assert!(t.rows.iter().all(|r| r.len() == wordcraft_doc::table::MAX_COLS));
-    // A narrow table is unchanged.
-    let FBlock::Table(t) = &parse("| a | b |\n| - | - |\n| x |\n").blocks[0] else { panic!("expected table") };
-    assert_eq!(t.rows[1].len(), 2);
-}

crates/layout/src/balloons.rs

@@ -74,8 +74,9 @@ pub fn anchors(doc: &Document) -> Vec<(u32, Pos)> {
     let mut out = Vec::new();
     for path in doc.para_paths(StoryRef::Body) {
         let Some(p) = doc.para(StoryRef::Body, &path) else { continue };
-        for off in p.object_offsets() {
-            let Some(InlineObject::CommentStart { id }) = p.object_at(off) else { continue };
+        // One pass over the objects: `object_at` per offset counted the objects before each one.
+        for (off, obj) in p.objects_with_offsets() {
+            let InlineObject::CommentStart { id } = obj else { continue };
             if !doc.comments.contains_key(id) || root(doc, *id) != *id || !seen.insert(*id) {
                 continue;
             }

crates/layout/src/tests/budget.rs

@@ -294,3 +294,20 @@ fn a_kept_outline_holds_on_to_its_pictures_allocation() {
     drop(disc);
     assert!(weak.upgrade().is_none(), "the bytes are freed with the document; only their allocation is kept");
 }
+
+#[test]
+fn comment_anchors_are_found_in_one_pass_over_a_paragraph() {
+    // 20,000 comment ends before the one start: each marker counted the objects before it again.
+    let n = 20_000usize;
+    let mut d = Document::from_text("");
+    d.comments.insert(1, wordcraft_doc::Comment::default());
+    if let Some(Block::Para(p)) = d.body.first_mut().map(Arc::make_mut) {
+        p.text = wordcraft_doc::para::OBJ.to_string().repeat(n + 1);
+        p.runs = vec![wordcraft_doc::para::Run { len: p.text.len(), props: Default::default() }];
+        p.objects = (0..n).map(|_| InlineObject::CommentEnd { id: 1 }).collect();
+        p.objects.push(InlineObject::CommentStart { id: 1 });
+    }
+    let found = balloons::anchors(&d);
+    assert_eq!(found.len(), 1);
+    assert_eq!(found[0].1.off, n * wordcraft_doc::para::OBJ.len_utf8());
+}