fix: preserve Prime layout contracts and require Figma-backed completion

.changepacks/changepack_log_h1Z8bhReFSk91gTrAJyLF.json

@@ -0,0 +1,7 @@
+{
+  "changes": {
+    "Cargo.toml": "Patch"
+  },
+  "note": "Preserve caller sizing and absolute rectangle geometry, emit route-owned pages, and require functional E2E plus native Figma visual evidence for completion. Teach split-screen concurrent desktop work with isolated project windows, inputs and visual-test viewports.",
+  "date": "2026-11-05T16:51:25.331465500Z"
+}

crates/devup-mcp-devup-ui/src/codegen/component/render_node.rs

@@ -109,6 +109,32 @@ fn render_node(
         let attributes = properties.iter().map(|(name, value)| {
             format!(" {name}={{{}}}", serde_json::to_string(value).unwrap())
         }).collect::<String>();
+        // A reference only passes variant props. Its master component cannot
+        // reproduce an instance's parent allocation by itself. Keep that loss
+        // actionable instead of treating a named reference as layout evidence.
+        let mut placement_props = Vec::new();
+        layout::push_layout_props(snapshot, node, "Box", &mut placement_props,
+            context.root_layout, depth == 0, context.width_policy.as_ref(), false);
+        let placement_props: serde_json::Map<String, serde_json::Value> = placement_props.into_iter()
+            .filter(|(name, _)| matches!(name.as_str(), "w" | "h" | "boxSize" | "minW" | "maxW" | "minH" | "maxH" | "flex" | "flexShrink" | "alignSelf" | "gridColumn" | "gridRow"))
+            .map(|(name, PropValue::String(value))| (name, serde_json::Value::String(value))).collect();
+        if !placement_props.is_empty() {
+            context.diagnostics.push(Diagnostic {
+                code: "DEVUP_CODEGEN_INSTANCE_PLACEMENT_CONTRACT".into(),
+                node_id: Some(node.id.clone()),
+                severity: Some(DiagnosticSeverity::Warning),
+                fidelity_impact: Some(devup_mcp_figma::FidelityImpact::Approximated),
+                message: "Component reference does not apply the instance's caller sizing; preserve its root placement contract during assembly.".into(),
+                details: Some(serde_json::json!({
+                    "component":component,"parentId":view.string("parentId"),
+                    "requiredRootProps":placement_props,
+                    "sourceSize":{"width":view.number("width"),"height":view.number("height")},
+                    "appliedToReference":false,
+                    "nextAction":"Apply these props to the actual component root through typed layout props or inline the captured instance. Do not add unsupported props to a component or assume maxW allocates width. Verify the assembled parent/child bounds alongside the Figma reference visual test."
+                })),
+                ..Diagnostic::default()
+            });
+        }
         let content = main_property.unwrap_or_else(|| format!("<{component}{attributes} />"));
         let expression = if let Some(visible) = visible_property {
             format!("{{{visible} && {content}}}")

crates/devup-mcp-devup-ui/src/codegen/evidence.rs

@@ -316,6 +316,13 @@ pub(super) fn placement_contract(
         requirements
             .push(include_str!("../text/evidence-placement_contract-adba181a.md").to_owned());
     }
+    if parent.is_none()
+        && ["layoutSizingHorizontal", "layoutSizingVertical"]
+            .iter()
+            .any(|axis| view.string(axis) == Some("FILL"))
+    {
+        requirements.push("This detached FILL root needs its original parent's layout direction and allocation. maxW/maxH alone do not allocate space. Restore the caller's flex/grid sizing from instanceOverrides or collect the containing parent; verify the assembled component in the browser.".into());
+    }
     if vertical_fill
         && (embedded
             || !view.number("height").is_some_and(|h| {

crates/devup-mcp-devup-ui/src/codegen/layout/layout_properties.rs

@@ -24,7 +24,7 @@ pub(super) fn push_layout_props(
             .child_ids()
             .any(|child| child == node.id)
     });
-    let is_root = snapshot.roots.iter().any(|root| root == &node.id);
+    let is_root = is_render_root || snapshot.roots.iter().any(|root| root == &node.id);
     // The parent of a collected root sits outside the collected subtree, so it
     // cannot be looked up and the node's recorded parent type is the only
     // account of it. Without that fallback a screen read as having no parent at
@@ -98,6 +98,15 @@ pub(super) fn push_layout_props(
         } else if let Some((w, h)) = fixed_native_ellipse_size(&view, component, is_asset) {
             width = Some(px(w));
             height = Some(px(h));
+        } else if let Some((w, h)) = fixed_native_rectangle_size(&view, component, is_asset) {
+            // Keep the existing full-parent overlay relationship on matching
+            // axes. A smaller, intrinsically empty shape needs its own extent.
+            let spans = |axis: &str, extent: f64| parent.is_some_and(|p| {
+                let p = p.typed_view();
+                p.field_error(axis).is_none() && p.number(axis) == Some(extent)
+            });
+            width = Some(if spans("width", w) { "100%".into() } else { px(w) });
+            height = Some(if spans("height", h) { "100%".into() } else { px(h) });
         } else if component == "Text" {
             width = own_width.map(px);
             height = Some("100%".to_owned());
@@ -308,6 +317,12 @@ pub(super) fn push_layout_props(
         }
     }
 
+    // A selected FILL root can have a FIXED opposite axis, so it may have
+    // taken the mixed-sizing branch before reaching the root branch above.
+    if is_render_root && !embedded_root && !absolute && !is_page_root && fill_w && width.is_none() {
+        width = Some("100%".into());
+    }
+
     // A canvas with positioned children is their coordinate system, not just
     // a responsive page measurement. Preserve each FIXED axis even on a page
     // or section root. Embedded mode explicitly delegates dimensions to host.
@@ -686,7 +701,8 @@ pub(super) fn push_layout_props(
             && let (Some(own), Some(room)) =
                 (view.number(size), inner_extent(parent, size, near, far))
             && own + 0.5 < room
-            && a_wider_box_would_show(&view, across_is_horizontal)
+            && (view.node_type() == "INSTANCE"
+                || a_wider_box_would_show(&view, across_is_horizontal))
         {
             string_prop(props, "alignSelf", "flex-start");
         }

crates/devup-mcp-devup-ui/src/codegen/layout/solid_ellipse.rs

@@ -26,3 +26,22 @@ fn fixed_native_ellipse_size(view: &TypedNode<'_>, component: &str, is_asset: bo
     let (width, height) = (view.number("width")?, view.number("height")?);
     (width.is_finite() && height.is_finite() && width > 0.0 && height > 0.0).then_some((width, height))
 }
+
+/// Rectangles have no intrinsic content either. Figma's shape API may omit
+/// layoutSizing*, unlike auto-layout frames; error-free measured axes and
+/// non-stretch constraints are enough to retain their native fixed geometry.
+fn fixed_native_rectangle_size(view: &TypedNode<'_>, component: &str, is_asset: bool) -> Option<(f64, f64)> {
+    if is_asset || component != "Box" || view.node_type() != "RECTANGLE"
+        || view.string("layoutPositioning") != Some("ABSOLUTE")
+        || view.child_ids().next().is_some()
+        || ["width", "height", "layoutPositioning", "layoutSizingHorizontal", "layoutSizingVertical", "constraints"]
+            .iter().any(|field| view.field_error(field).is_some())
+        || ["layoutSizingHorizontal", "layoutSizingVertical"].iter()
+            .any(|field| view.string(field).is_some_and(|sizing| sizing != "FIXED"))
+        || ["horizontal", "vertical"].iter().any(|axis| view.value("constraints")
+            .and_then(|constraints| constraints.get(axis)).and_then(Value::as_str)
+            .is_some_and(|constraint| matches!(constraint, "STRETCH" | "SCALE")))
+    { return None; }
+    let (width, height) = (view.number("width")?, view.number("height")?);
+    (width.is_finite() && height.is_finite() && width > 0.0 && height > 0.0).then_some((width, height))
+}

crates/devup-mcp-devup-ui/tests/fixed_absolute_ellipses.rs

@@ -88,7 +88,7 @@ fn fluid_unknown_and_unreadable_geometry_do_not_gain_fixed_shape_sizes() {
 }
 
 #[test]
-fn relative_ellipse_and_other_shape_paths_keep_their_existing_sizing() {
+fn relative_ellipses_keep_their_path_and_absolute_rectangles_preserve_measured_axes() {
     for positioning in [json!("AUTO"), json!({"$unsupported":"unknown"})] {
         let mut snapshot = source("I44:2832;44:3209");
         snapshot
@@ -107,5 +107,5 @@ fn relative_ellipse_and_other_shape_paths_keep_their_existing_sizing() {
         .unwrap()
         .node_type = "RECTANGLE".into();
     let output = render(&snapshot);
-    assert!(!output.contains("boxSize=\"48px\""), "{output}");
+    assert!(output.contains("boxSize=\"48px\""), "{output}");
 }

crates/devup-mcp-devup-ui/tests/fixtures/prime-placement.json

@@ -0,0 +1,132 @@
+{
+  "fileKey": "prime-placement-feedback",
+  "roots": [
+    "row"
+  ],
+  "diagnostics": [],
+  "nodes": {
+    "row": {
+      "id": "row",
+      "type": "FRAME",
+      "fields": {
+        "name": "RenderFixture",
+        "parentType": "FRAME",
+        "width": 980,
+        "height": 250,
+        "layoutMode": "HORIZONTAL",
+        "layoutSizingHorizontal": "FIXED",
+        "layoutSizingVertical": "HUG",
+        "itemSpacing": 40,
+        "childrenIds": [
+          "title",
+          "card"
+        ],
+        "inferredAutoLayout": {
+          "layoutMode": "HORIZONTAL",
+          "itemSpacing": 40
+        }
+      }
+    },
+    "title": {
+      "id": "title",
+      "type": "INSTANCE",
+      "fields": {
+        "name": "StepTitle",
+        "parentId": "row",
+        "width": 420,
+        "height": 94,
+        "maxWidth": 420,
+        "layoutMode": "VERTICAL",
+        "layoutSizingHorizontal": "FILL",
+        "layoutSizingVertical": "HUG",
+        "itemSpacing": 12,
+        "childrenIds": [
+          "title-content"
+        ],
+        "inferredAutoLayout": {
+          "layoutMode": "VERTICAL",
+          "itemSpacing": 12
+        }
+      }
+    },
+    "title-content": {
+      "id": "title-content",
+      "type": "FRAME",
+      "fields": {
+        "parentId": "title",
+        "width": 120,
+        "height": 94,
+        "layoutSizingHorizontal": "FIXED",
+        "layoutSizingVertical": "FIXED",
+        "fills": [
+          {
+            "type": "SOLID",
+            "color": {
+              "r": 0.1,
+              "g": 0.1,
+              "b": 0.1
+            }
+          }
+        ]
+      }
+    },
+    "card": {
+      "id": "card",
+      "type": "FRAME",
+      "fields": {
+        "name": "StepCard",
+        "parentId": "row",
+        "width": 520,
+        "height": 218,
+        "layoutMode": "VERTICAL",
+        "layoutSizingHorizontal": "FIXED",
+        "layoutSizingVertical": "FIXED",
+        "layoutPositioning": "AUTO",
+        "childrenIds": [
+          "marker"
+        ],
+        "fills": [
+          {
+            "type": "SOLID",
+            "color": {
+              "r": 0.97,
+              "g": 0.97,
+              "b": 0.98
+            }
+          }
+        ],
+        "inferredAutoLayout": {
+          "layoutMode": "VERTICAL"
+        }
+      }
+    },
+    "marker": {
+      "id": "marker",
+      "type": "RECTANGLE",
+      "fields": {
+        "name": "Rectangle 37",
+        "parentId": "card",
+        "width": 16,
+        "height": 16,
+        "x": -48,
+        "y": 32,
+        "layoutPositioning": "ABSOLUTE",
+        "constraints": {
+          "horizontal": "MIN",
+          "vertical": "MIN"
+        },
+        "cornerRadius": 1000,
+        "fills": [
+          {
+            "type": "SOLID",
+            "color": {
+              "r": 0.3176470588235294,
+              "g": 0.23529411764705882,
+              "b": 0.9333333333333333
+            }
+          }
+        ]
+      }
+    }
+  }
+}