Fix individual table cells being split

Each cell must be wrapped in ui.horizontal. This unfortunately requires
parsing the table before drawing the events.

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Fixed
+
+- A single table cell split into multiple cells ([#35](https://github.com/lampsitter/egui_commonmark/pull/35))
+
 ## 0.13.0 - 2024-02-20
 
 ### Added

examples/book.rs

@@ -124,6 +124,10 @@ fn main() {
                         name: "Block Quotes ".to_owned(),
                         content: include_str!("markdown/blockquotes.md").to_owned(),
                     },
+                    Page {
+                        name: "Tables ".to_owned(),
+                        content: include_str!("markdown/tables.md").to_owned(),
+                    },
                 ],
             })
         }),

examples/markdown/tables.md

@@ -0,0 +1,9 @@
+# Tables
+
+Column A   | Column B
+-----------|----------
+`item` `a1` | item b1
+item a2 | item b2
+item a3 | item b3
+item a4 | item b4
+

src/parsers/pulldown.rs

@@ -38,6 +38,59 @@ fn delayed_events<'e>(
     }
 }
 
+struct Column<'e>(Vec<pulldown_cmark::Event<'e>>);
+struct Row<'e>(Vec<Column<'e>>);
+
+struct Table<'e> {
+    header: Row<'e>,
+    rows: Vec<Row<'e>>,
+}
+
+fn parse_row<'e>(events: &mut impl Iterator<Item = pulldown_cmark::Event<'e>>) -> Vec<Column<'e>> {
+    let mut row = Vec::new();
+    let mut column = Vec::new();
+
+    for e in events.by_ref() {
+        if let pulldown_cmark::Event::End(pulldown_cmark::TagEnd::TableCell) = e {
+            row.push(Column(column));
+            column = Vec::new();
+        }
+
+        if let pulldown_cmark::Event::End(pulldown_cmark::TagEnd::TableHead) = e {
+            break;
+        }
+
+        if let pulldown_cmark::Event::End(pulldown_cmark::TagEnd::TableRow) = e {
+            break;
+        }
+
+        column.push(e);
+    }
+
+    row
+}
+
+fn parse_table<'e>(
+    events: &mut impl Iterator<Item = (usize, pulldown_cmark::Event<'e>)>,
+) -> Table<'e> {
+    let mut all_events = delayed_events(events, pulldown_cmark::TagEnd::Table)
+        .into_iter()
+        .peekable();
+
+    let header = parse_row(&mut all_events);
+
+    let mut rows = Vec::new();
+    while all_events.peek().is_some() {
+        let row = parse_row(&mut all_events);
+        rows.push(Row(row));
+    }
+
+    Table {
+        header: Row(header),
+        rows,
+    }
+}
+
 /// try to parse events as an alert quote block. This ill modify the events
 /// to remove the parsed text that should not be rendered.
 /// Assumes that the first element is a Paragraph
@@ -352,17 +405,35 @@ impl CommonMarkViewerInternal {
         if self.is_table {
             newline(ui);
 
-            egui::Frame::group(ui.style()).show(ui, |ui| {
-                let id = self.source_id.with(self.curr_table);
-                self.curr_table += 1;
+            let id = self.source_id.with(self.curr_table);
+            self.curr_table += 1;
+
+            ui.push_id(id, |ui| {
+                let Table { header, rows } = parse_table(events);
+
                 egui::Grid::new(id).striped(true).show(ui, |ui| {
-                    while self.is_table {
-                        if let Some((_, e)) = events.next() {
-                            self.should_insert_newline = false;
-                            self.event(ui, e, cache, options, max_width);
-                        } else {
-                            break;
+                    for col in header.0 {
+                        ui.horizontal(|ui| {
+                            for e in col.0 {
+                                self.should_insert_newline = false;
+                                self.event(ui, e, cache, options, max_width);
+                            }
+                        });
+                    }
+
+                    ui.end_row();
+
+                    for row in rows {
+                        for col in row.0 {
+                            ui.horizontal(|ui| {
+                                for e in col.0 {
+                                    self.should_insert_newline = false;
+                                    self.event(ui, e, cache, options, max_width);
+                                }
+                            });
                         }
+
+                        ui.end_row();
                     }
                 });
             });
@@ -535,12 +606,8 @@ impl CommonMarkViewerInternal {
             pulldown_cmark::TagEnd::Table => {
                 self.is_table = false;
             }
-            pulldown_cmark::TagEnd::TableHead => {
-                ui.end_row();
-            }
-            pulldown_cmark::TagEnd::TableRow => {
-                ui.end_row();
-            }
+            pulldown_cmark::TagEnd::TableHead => {}
+            pulldown_cmark::TagEnd::TableRow => {}
             pulldown_cmark::TagEnd::TableCell => {
                 // Ensure space between cells
                 ui.label("  ");