fix(fig): preserve imported layout metadata

- Keep Figma stack sizing fields such as RESIZE_TO_FIT_WITH_IMPLICIT_SIZE
- Avoid writing default auto-layout fields onto imported instances when Figma omitted them
- Cover instance layout metadata roundtrips

packages/core/src/kiwi/node-change/convert.ts

@@ -355,6 +355,7 @@ function convertLayoutProps(
 ): Pick<
   SceneNode,
   | 'layoutMode'
+  | 'figmaLayout'
   | 'itemSpacing'
   | 'paddingTop'
   | 'paddingBottom'
@@ -387,6 +388,27 @@ function convertLayoutProps(
 
   return {
     layoutMode,
+    figmaLayout: {
+      stackMode: nc.stackMode,
+      stackSpacing: nc.stackSpacing,
+      stackPadding: nc.stackPadding,
+      stackPaddingRight: nc.stackPaddingRight,
+      stackPaddingBottom: nc.stackPaddingBottom,
+      stackCounterAlign: nc.stackCounterAlign,
+      stackJustify: nc.stackJustify,
+      stackCounterAlignItems: nc.stackCounterAlignItems,
+      stackPrimaryAlignItems: nc.stackPrimaryAlignItems,
+      stackPrimarySizing: nc.stackPrimarySizing,
+      stackCounterSizing: nc.stackCounterSizing,
+      stackVerticalPadding: nc.stackVerticalPadding,
+      stackHorizontalPadding: nc.stackHorizontalPadding,
+      stackWrap: nc.stackWrap,
+      stackPositioning: nc.stackPositioning,
+      stackChildPrimaryGrow: nc.stackChildPrimaryGrow,
+      stackChildAlignSelf: nc.stackChildAlignSelf,
+      stackCounterSpacing: nc.stackCounterSpacing,
+      bordersTakeSpace: nc.bordersTakeSpace as boolean | undefined
+    },
     itemSpacing: nc.stackSpacing ?? 0,
     ...convertLayoutPadding(nc),
     primaryAxisSizing,

packages/core/src/kiwi/node-change/serialize.ts

@@ -322,8 +322,53 @@ function serializeTextProps(
   }
 }
 
+function normalizeStackMode(
+  value: string | undefined
+): KiwiNodeChange['stackMode'] {
+  return value === 'HORIZONTAL' || value === 'VERTICAL' || value === 'NONE' ? value : undefined
+}
+
+function normalizeStackSizing(
+  value: string | undefined
+): KiwiNodeChange['stackPrimarySizing'] {
+  return value === 'FIXED' || value === 'RESIZE_TO_FIT' || value === 'RESIZE_TO_FIT_WITH_IMPLICIT_SIZE'
+    ? value
+    : undefined
+}
+
+function normalizeStackJustify(value: string | undefined): string | undefined {
+  return value === 'SPACE_EVENLY' ? 'SPACE_BETWEEN' : value
+}
+
+function normalizeStackCounterAlign(value: string | undefined): string | undefined {
+  return value === 'SPACE_EVENLY' ? 'SPACE_BETWEEN' : value
+}
+
 function serializeLayoutProps(node: SceneNode, nc: KiwiNodeChange): void {
   upsertPluginData(node, LAYOUT_DIRECTION_PLUGIN_KEY, node.layoutDirection)
+  const figmaLayout = node.figmaLayout
+  if (figmaLayout) {
+    nc.stackMode = normalizeStackMode(figmaLayout.stackMode)
+    nc.stackSpacing = figmaLayout.stackSpacing
+    nc.stackPadding = figmaLayout.stackPadding
+    nc.stackPaddingRight = figmaLayout.stackPaddingRight
+    nc.stackPaddingBottom = figmaLayout.stackPaddingBottom
+    nc.stackCounterAlign = normalizeStackCounterAlign(figmaLayout.stackCounterAlign)
+    nc.stackJustify = normalizeStackJustify(figmaLayout.stackJustify)
+    nc.stackCounterAlignItems = normalizeStackCounterAlign(figmaLayout.stackCounterAlignItems)
+    nc.stackPrimaryAlignItems = normalizeStackJustify(figmaLayout.stackPrimaryAlignItems)
+    nc.stackPrimarySizing = normalizeStackSizing(figmaLayout.stackPrimarySizing)
+    nc.stackCounterSizing = normalizeStackSizing(figmaLayout.stackCounterSizing)
+    nc.stackVerticalPadding = figmaLayout.stackVerticalPadding
+    nc.stackHorizontalPadding = figmaLayout.stackHorizontalPadding
+    nc.stackWrap = figmaLayout.stackWrap
+    nc.stackPositioning = figmaLayout.stackPositioning
+    nc.stackChildPrimaryGrow = figmaLayout.stackChildPrimaryGrow
+    nc.stackChildAlignSelf = figmaLayout.stackChildAlignSelf
+    nc.stackCounterSpacing = figmaLayout.stackCounterSpacing
+    nc.bordersTakeSpace = figmaLayout.bordersTakeSpace
+    return
+  }
   if (node.layoutMode !== 'NONE' && node.layoutMode !== 'GRID') {
     nc.stackMode = node.layoutMode
     nc.stackSpacing = node.itemSpacing

packages/core/src/scene-graph/node-defaults.ts

@@ -46,6 +46,7 @@ export function createDefaultNode(
     lineHeight: null,
     letterSpacing: 0,
     layoutMode: 'NONE',
+    figmaLayout: null,
     layoutDirection: 'AUTO',
     layoutWrap: 'NO_WRAP',
     primaryAxisAlign: 'MIN',

packages/core/src/scene-graph/types.ts

@@ -229,6 +229,34 @@ export interface VariantPropSpec {
   value: string
 }
 
+export type FigmaLayoutMetadata = Partial<
+  Record<
+    | 'stackMode'
+    | 'stackCounterAlign'
+    | 'stackJustify'
+    | 'stackCounterAlignItems'
+    | 'stackPrimaryAlignItems'
+    | 'stackPrimarySizing'
+    | 'stackCounterSizing'
+    | 'stackWrap'
+    | 'stackPositioning'
+    | 'stackChildAlignSelf',
+    string
+  > &
+    Record<
+      | 'stackSpacing'
+      | 'stackPadding'
+      | 'stackPaddingRight'
+      | 'stackPaddingBottom'
+      | 'stackVerticalPadding'
+      | 'stackHorizontalPadding'
+      | 'stackChildPrimaryGrow'
+      | 'stackCounterSpacing',
+      number
+    > &
+    Record<'bordersTakeSpace', boolean>
+>
+
 export interface SceneNode {
   id: string
   type: NodeType
@@ -283,6 +311,7 @@ export interface SceneNode {
   verticalConstraint: ConstraintType
 
   layoutMode: LayoutMode
+  figmaLayout: FigmaLayoutMetadata | null
   layoutDirection: LayoutDirection
   layoutWrap: LayoutWrap
   primaryAxisAlign: LayoutAlign

tests/engine/kiwi/serialize-fixes/auto-layout/transforms.test.ts

@@ -130,6 +130,63 @@ describe('Fix 1: auto-layout child transforms', () => {
     expect(childNc.transform.m12).toBe(45)
   })
 
+  test('preserves imported Figma layout metadata for instance roundtrips', () => {
+    const graph = new SceneGraph()
+    const parent = graph.createNode('FRAME', pageId(graph), {
+      name: 'Checked List',
+      width: 878,
+      height: 24,
+      layoutMode: 'HORIZONTAL',
+      counterAxisSizing: 'HUG',
+      layoutAlignSelf: 'STRETCH',
+      figmaLayout: {
+        stackMode: 'HORIZONTAL',
+        stackPrimarySizing: 'FIXED',
+        stackCounterSizing: 'RESIZE_TO_FIT_WITH_IMPLICIT_SIZE',
+        stackChildAlignSelf: 'STRETCH'
+      }
+    })
+
+    graph.createNode('INSTANCE', parent.id, {
+      name: 'Lists',
+      width: 282.6666564941406,
+      height: 24,
+      layoutMode: 'VERTICAL',
+      layoutGrow: 1,
+      figmaLayout: {
+        stackMode: 'VERTICAL',
+        stackChildPrimaryGrow: 1
+      }
+    })
+
+    const blobs: Uint8Array[] = []
+    const changes = sceneNodeToKiwi(
+      getNodeOrThrow(graph, parent.id),
+      ROOT_GUID,
+      0,
+      { value: 100 },
+      graph,
+      blobs
+    ) as Record<string, unknown>[]
+
+    const parentNc = expectDefined(
+      changes.find((nc) => nc.name === 'Checked List'),
+      'parent node change'
+    )
+    expect(parentNc.stackCounterSizing).toBe('RESIZE_TO_FIT_WITH_IMPLICIT_SIZE')
+
+    const instanceNc = expectDefined(
+      changes.find((nc) => nc.name === 'Lists'),
+      'instance node change'
+    )
+    expect(instanceNc.stackMode).toBe('VERTICAL')
+    expect(instanceNc.stackChildPrimaryGrow).toBe(1)
+    expect(instanceNc.stackPrimarySizing).toBeUndefined()
+    expect(instanceNc.stackCounterSizing).toBeUndefined()
+    expect(instanceNc.stackPrimaryAlignItems).toBeUndefined()
+    expect(instanceNc.stackCounterAlignItems).toBeUndefined()
+  })
+
   test('horizontal auto-layout child also preserves its stored transform offsets', () => {
     const graph = new SceneGraph()
     const parent = graph.createNode('FRAME', pageId(graph), {