3D (Classic): effect.lightingPreset refuses Extrude & Bevel (Classic)

Extrude & Bevel (Classic) has no lighting presets; its lights are set in
its own options. effect.lightingPreset now refuses a target whose effect
at the index is Extrude & Bevel (Classic) with an error that names it,
before any object changes. Before, every preset failed on it with an
unknown-parameter error for lightColor. The params text and docs/mcp.md
state the rule.

crates/engine/src/cmd/effectcmd.rs

@@ -62,7 +62,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "3D Lighting Preset",
             [],
             None,
-            "{index: int, preset: standard|diffuse|topLeft|right, item?: appearance item index|null (omitted: the active item, else the object's), ids?|id?: [..], target?: object|contents, aligned?: bool (index and item are rows of the first target's stack: each other target edits its equal one, as the Appearance panel does for a mixed selection)} replace an applied 3D effect's light rig and ambient with an original lighting preset; preserve shading, geometry and view; all targets must have a 3D effect at index; one undo step → {ids}",
+            "{index: int, preset: standard|diffuse|topLeft|right, item?: appearance item index|null (omitted: the active item, else the object's), ids?|id?: [..], target?: object|contents, aligned?: bool (index and item are rows of the first target's stack: each other target edits its equal one, as the Appearance panel does for a mixed selection)} replace an applied 3D effect's light rig and ambient with an original lighting preset; preserve shading, geometry and view; all targets must have a 3D effect at index other than Extrude & Bevel (Classic), which has no lighting presets; one undo step → {ids}",
             has_doc,
             lighting_preset
         ),
@@ -441,6 +441,13 @@ fn lighting_preset(s: &mut Session, p: &Value) -> Result<Value> {
         if !effect.is_some_and(|e| effects::is_three_d(&e.id)) {
             return Err(bad(C, format!("object {} needs a 3D effect at index {index}", id.0)));
         }
+        // Extrude & Bevel (Classic) has no lighting presets; its lights are set in its own options.
+        if effect.is_some_and(|e| e.id == effects::CLASSIC_EXTRUDE) {
+            return Err(bad(
+                C,
+                format!("object {}: Extrude & Bevel (Classic) at index {index} has no lighting presets; set its lights with effect.setParams", id.0),
+            ));
+        }
     }
     let mut options = p.clone();
     let map = options.as_object_mut().ok_or_else(|| bad(C, "parameters must be an object"))?;

crates/engine/src/cmd/effectcmd/lighting_presets_tests.rs

@@ -91,3 +91,27 @@ fn lighting_presets_reject_a_mixed_selection_before_changing_any_effect() {
     assert_eq!(s.doc().unwrap().history.undo.len(), history);
     assert!(!s.doc().unwrap().is_dirty());
 }
+
+#[test]
+fn lighting_presets_refuse_extrude_and_bevel_classic_and_leave_a_mixed_selection_unchanged() {
+    let (mut s, first) = setup("threeD.rotate", Value::Null);
+    let classic = s.execute("shape.rectangle", &json!({"x":250,"y":100,"width":80,"height":80})).unwrap()["id"].as_u64().unwrap();
+    s.execute("effect.apply", &json!({"effect":"threeD.classicExtrude","item":null,"params":{"surface":"diffuse","lightRotation":40}})).unwrap();
+    for ids in [vec![classic], vec![first.0, classic]] {
+        for preset in LIGHTING_PRESETS {
+            s.doc_mut().unwrap().mark_saved();
+            let before = s.doc().unwrap().doc.clone();
+            let history = s.doc().unwrap().history.undo.len();
+            let p = json!({"ids":ids,"index":0,"item":null,"preset":preset.id});
+            let err = s.execute("effect.lightingPreset", &p).unwrap_err().to_string();
+            assert!(err.contains(&format!("object {classic}: Extrude & Bevel (Classic) at index 0 has no lighting presets")), "{err}");
+            assert_eq!(s.doc().unwrap().doc, before);
+            assert_eq!(s.doc().unwrap().history.undo.len(), history);
+            assert!(!s.doc().unwrap().is_dirty());
+        }
+    }
+    // Its lights are set with its own parameters instead.
+    s.execute("effect.setParams", &json!({"ids":[classic],"index":0,"item":null,"params":{"lightRotation":135,"lightHeight":45}})).unwrap();
+    let params = &s.doc().unwrap().doc.node(NodeId(classic)).unwrap().appearance.effects[0].params;
+    assert_eq!((params["lightRotation"].as_f64(), params["lightHeight"].as_f64()), (Some(135.0), Some(45.0)));
+}

docs/mcp.md

@@ -2137,8 +2137,9 @@ See [Revolve](revolve.md) for the scope and limitations.
 `effect.lightingPreset {index: int, preset: "standard" | "diffuse" | "topLeft" | "right", item?, ids?, target?}`
 replaces the lighting rig and ambient of an existing Revolve, Extrude & Bevel, Inflate or Rotate
 effect. `item: null` addresses object-level effects; an item index addresses a fill/stroke's
-effects. All targets must have a 3D effect at `index`, otherwise nothing changes. The operation
-is one undo step and preserves Shading, geometry, source paint and the view.
+effects. All targets must have a 3D effect at `index`, otherwise nothing changes. Extrude & Bevel
+(Classic) has no lighting presets: a target with it at `index` is an error, nothing changes, and
+`effect.setParams` sets its lights. The operation is one undo step and preserves Shading, geometry, source paint and the view.
 
 The four original rigs use one white front light at 80% intensity. Standard keeps the existing
 default; Diffuse uses 100% Softness and 35% Ambient Light, Top Left uses Rotation 135 and Height