Cycle list markers by default (#2788)

Co-authored-by: Laurenz <laurmaedje@gmail.com>

crates/typst/src/model/list.rs

@@ -69,7 +69,7 @@ pub struct ListElem {
     ///
     /// Instead of plain content, you can also pass an array with multiple
     /// markers that should be used for nested lists. If the list nesting depth
-    /// exceeds the number of markers, the last one is repeated. For total
+    /// exceeds the number of markers, the markers are cycled. For total
     /// control, you may pass a function that maps the list's nesting depth
     /// (starting from `{0}`) to a desired marker.
     ///
@@ -85,7 +85,14 @@ pub struct ListElem {
     /// - Items
     /// ```
     #[borrowed]
-    #[default(ListMarker::Content(vec![TextElem::packed('•')]))]
+    #[default(ListMarker::Content(vec![
+        // These are all available in the default font, vertically centered, and
+        // roughly of the same size (with the last one having slightly lower
+        // weight because it is not filled).
+        TextElem::packed('\u{2022}'), // Bullet
+        TextElem::packed('\u{2023}'), // Triangular Bullet
+        TextElem::packed('\u{2013}'), // En-dash
+    ]))]
     pub marker: ListMarker,
 
     /// The indent of each item.
@@ -202,7 +209,7 @@ impl ListMarker {
     fn resolve(&self, engine: &mut Engine, depth: usize) -> SourceResult<Content> {
         Ok(match self {
             Self::Content(list) => {
-                list.get(depth).or(list.last()).cloned().unwrap_or_default()
+                list.get(depth % list.len()).cloned().unwrap_or_default()
             }
             Self::Func(func) => func.call(engine, [depth])?.display(),
         })

tests/typ/layout/list-marker.typ

@@ -7,7 +7,7 @@
 - B
 
 ---
-// Test that last item is repeated.
+// Test that items are cycled.
 #set list(marker: ([--], [•]))
 - A
   - B