Engine: a failed batch gives back the highlighted Layers panel rows

`command.batch` rolls a failed batch back through each document's interaction, which restored the
art, the selection, the current layer and isolation but not the highlighted Layers panel rows. A
batch whose `layer.setCurrent` step ran before a later step failed left that layer's row
highlighted, so a following Collect in New Layer collected the layer instead of the selected art.
The failed batch isn't journaled, so replaying the journal gave a different document: the
`journal_replay_reproduces_document` property test failed whenever it drew that sequence.

The interaction now keeps the highlighted rows too, which also puts them back when a drag is
cancelled.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/engine/src/lib.rs

@@ -79,8 +79,10 @@ pub struct Interaction {
     pub doc: Arc<Document>,
     pub selection: Selection,
     pub preview: Option<(String, Value)>,
-    /// Per-document state restored on cancel (current layer, isolation).
+    /// Per-document state restored on cancel (current layer, highlighted Layers panel rows,
+    /// isolation).
     pub active_layer: Option<NodeId>,
+    pub layer_rows: Vec<NodeId>,
     pub isolation: Option<NodeId>,
     /// The perspective transform the previews make (`perspective.transform` params): Transform
     /// Again repeats it once the drag is committed.
@@ -206,6 +208,7 @@ impl DocState {
             self.doc = it.doc;
             self.selection = it.selection;
             self.active_layer = it.active_layer;
+            self.layer_rows = it.layer_rows;
             self.isolation = it.isolation;
             self.revision += 1;
         }
@@ -1114,6 +1117,7 @@ impl Session {
             selection: st.selection.clone(),
             preview: None,
             active_layer: st.active_layer,
+            layer_rows: st.layer_rows.clone(),
             isolation: st.isolation,
             perspective_again: None,
         });

crates/engine/src/tests_journal.rs

@@ -231,3 +231,21 @@ fn a_failed_batch_brings_back_a_document_it_reverted() {
     assert!(st.is_dirty() && st.interaction.is_none());
     assert!(st.revision > revision, "the restored document redraws");
 }
+
+#[test]
+fn a_failed_batch_gives_back_the_highlighted_rows_and_the_current_layer() {
+    let mut s = Session::new();
+    s.execute("file.new", &json!({"created": null})).unwrap();
+    let layer = s.doc().unwrap().doc.layers[0].id;
+    // A step that highlights the layer's row, then one that fails: the highlight goes back too.
+    let steps = json!([{"command": "layer.setCurrent", "params": {"id": layer.0}}, {"command": "no.such.command"}]);
+    assert!(s.execute("command.batch", &json!({ "commands": steps })).is_err());
+    assert!(s.doc().unwrap().layer_rows.is_empty(), "no row stays highlighted");
+    assert_eq!(s.doc().unwrap().active_layer, Some(layer));
+    // So Collect in New Layer acts on the drawn rectangle, as it does when the journal is replayed
+    // (a failed batch isn't journaled).
+    s.execute("shape.rectangle", &json!({"x": 0, "y": 0, "width": 1, "height": 1})).unwrap();
+    s.execute("layer.collectInNew", &json!({})).unwrap();
+    let r = replayed(&s);
+    assert_eq!(documents(&r), documents(&s));
+}