chore(lint): ban broad function types

- Add structural lint rules for broad Function usage and globalThis deletion outside tests
- Type design JSX component factories with an explicit callable signature
- Replace remaining broad Kiwi serialization test records with unknown values

lint/plugin.js

@@ -805,6 +805,57 @@ const noUnknownRecordDoubleCast = {
   }
 }
 
+const noFunctionType = {
+  meta: {
+    docs: {
+      description: 'Disallow the broad Function type; use an explicit callable signature'
+    }
+  },
+  create(context) {
+    return {
+      TSTypeReference(node) {
+        if (node.typeName?.type !== 'Identifier' || node.typeName.name !== 'Function') return
+        context.report({
+          node,
+          message: 'Use an explicit function signature instead of the broad Function type.'
+        })
+      }
+    }
+  }
+}
+
+const noReflectDeleteGlobalThisOutsideTests = {
+  meta: {
+    docs: {
+      description: 'Disallow Reflect.deleteProperty(globalThis, ...) outside tests'
+    }
+  },
+  create(context) {
+    const file = normalizedFilename(context)
+    if (file.includes('/tests/')) return {}
+
+    return {
+      CallExpression(node) {
+        if (node.callee?.type !== 'MemberExpression') return
+        if (node.callee.object?.type !== 'Identifier' || node.callee.object.name !== 'Reflect')
+          return
+        if (
+          node.callee.property?.type !== 'Identifier' ||
+          node.callee.property.name !== 'deleteProperty'
+        )
+          return
+        const firstArg = node.arguments?.[0]
+        if (firstArg?.type !== 'Identifier' || firstArg.name !== 'globalThis') return
+        context.report({
+          node,
+          message:
+            'Do not mutate globalThis outside tests; isolate platform state behind a boundary.'
+        })
+      }
+    }
+  }
+}
+
 const noTsSuppressionComments = {
   meta: {
     docs: {
@@ -1342,6 +1393,8 @@ const plugin = {
     'no-broad-double-cast': noBroadDoubleCast,
     'no-unknown-record-double-cast': noUnknownRecordDoubleCast,
     'no-ts-suppression-comments': noTsSuppressionComments,
+    'no-function-type': noFunctionType,
+    'no-reflect-delete-global-this-outside-tests': noReflectDeleteGlobalThisOutsideTests,
     'no-core-browser-globals': noCoreBrowserGlobals,
     'no-direct-graph-emitter-subscriptions': noDirectGraphEmitterSubscriptions,
     'no-on-unmounted-in-composition-roots': noOnUnmountedInCompositionRoots,

oxlint.json

@@ -113,6 +113,8 @@
     "open-pencil/no-broad-double-cast": "error",
     "open-pencil/no-unknown-record-double-cast": "error",
     "open-pencil/no-ts-suppression-comments": "error",
+    "open-pencil/no-function-type": "error",
+    "open-pencil/no-reflect-delete-global-this-outside-tests": "error",
     "open-pencil/no-core-browser-globals": "error",
     "open-pencil/no-function-alias-imports": "error",
     "open-pencil/max-composition-root-lines": ["error", { "max": 260 }]

oxlint.structure.json

@@ -11,6 +11,12 @@
       "rules": {
         "no-unused-vars": "off"
       }
+    },
+    {
+      "files": ["packages/core/src/kiwi/kiwi-schema/**"],
+      "rules": {
+        "typescript/no-explicit-any": "off"
+      }
     }
   ],
   "rules": {
@@ -39,6 +45,9 @@
     "open-pencil/no-broad-double-cast": "error",
     "open-pencil/no-unknown-record-double-cast": "error",
     "open-pencil/no-ts-suppression-comments": "error",
+    "open-pencil/no-function-type": "error",
+    "open-pencil/no-reflect-delete-global-this-outside-tests": "error",
+    "typescript/no-explicit-any": "error",
     "open-pencil/no-core-browser-globals": "error",
     "open-pencil/no-direct-graph-emitter-subscriptions": "error",
     "open-pencil/no-on-unmounted-in-composition-roots": "error",

packages/core/src/design-jsx/mini-react.ts

@@ -1,5 +1,7 @@
+export type ComponentType = (props: Record<string, unknown>) => ReactNode
+
 export type ReactElement = {
-  type: string | Function
+  type: string | ComponentType
   props: Record<string, unknown> & { children?: ReactNode[] }
 }
 
@@ -8,7 +10,7 @@ export type ReactNode = ReactElement | string | number | null | undefined | Reac
 export type FC<P = Record<string, unknown>> = (props: P) => ReactElement
 
 export function createElement(
-  type: string | Function,
+  type: string | ComponentType,
   props: Record<string, unknown> | null,
   ...children: ReactNode[]
 ): ReactElement {

packages/core/src/design-jsx/render.ts

@@ -10,7 +10,7 @@ import type { SceneGraph } from '#core/scene-graph'
  * Build a component function from a JSX string using sucrase.
  * Works in both Node/Bun and the browser (no native bindings).
  */
-export function buildComponent(jsxString: string): () => unknown {
+export function buildComponent(jsxString: string): React.ComponentType {
   const trimmed = jsxString.trim()
 
   const aliases = `
@@ -37,7 +37,7 @@ export function buildComponent(jsxString: string): () => unknown {
   }
 
   // eslint-disable-next-line typescript-eslint/no-implied-eval -- sucrase output must be evaluated at runtime
-  return new Function('React', code)(React) as () => unknown
+  return new Function('React', code)(React) as React.ComponentType
 }
 
 interface RenderJSXOptions {

packages/core/src/profiler/draw-call-counter.ts

@@ -6,11 +6,12 @@ const DRAW_METHODS = [
 ] as const
 
 type DrawMethod = (typeof DRAW_METHODS)[number]
+type DrawFunction = (...args: unknown[]) => void
 
 export class DrawCallCounter {
   count = 0
 
-  private originals = new Map<DrawMethod, (...args: unknown[]) => void>()
+  private originals = new Map<DrawMethod, DrawFunction>()
   private gl: WebGL2RenderingContext | null
 
   constructor(gl: WebGL2RenderingContext | null) {
@@ -18,10 +19,10 @@ export class DrawCallCounter {
     if (!gl) return
 
     for (const method of DRAW_METHODS) {
-      const original = gl[method].bind(gl) as (...args: unknown[]) => void
+      const original = gl[method].bind(gl) as DrawFunction
       this.originals.set(method, original)
       // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment -- monkey-patching overloaded WebGL draw methods
-      ;(gl[method] as Function) = (...args: unknown[]) => {
+      ;(gl[method] as DrawFunction) = (...args: unknown[]) => {
         this.count++
         original(...args)
       }
@@ -39,7 +40,7 @@ export class DrawCallCounter {
     if (!gl) return
 
     for (const [method, fn] of this.originals) {
-      ;(gl[method] as Function) = fn
+      ;(gl[method] as DrawFunction) = fn
     }
     this.originals.clear()
   }

tests/engine/kiwi-serialize-fixes.test.ts

@@ -61,7 +61,7 @@ describe('Fix 1: auto-layout child transforms', () => {
       { value: 100 },
       graph,
       blobs
-    ) as Record<string, any>[]
+    ) as Record<string, unknown>[]
 
     // changes[0] = parent, changes[1] = child
     const childNc = changes.find((nc) => nc.name === 'Child')!
@@ -99,7 +99,7 @@ describe('Fix 1: auto-layout child transforms', () => {
       { value: 100 },
       graph,
       blobs
-    ) as Record<string, any>[]
+    ) as Record<string, unknown>[]
 
     const absNc = changes.find((nc) => nc.name === 'AbsChild')!
     expect(absNc).toBeDefined()
@@ -134,7 +134,7 @@ describe('Fix 1: auto-layout child transforms', () => {
       { value: 100 },
       graph,
       blobs
-    ) as Record<string, any>[]
+    ) as Record<string, unknown>[]
 
     const childNc = changes.find((nc) => nc.name === 'Child')!
     expect(childNc).toBeDefined()
@@ -170,7 +170,7 @@ describe('Fix 1: auto-layout child transforms', () => {
       { value: 100 },
       graph,
       blobs
-    ) as Record<string, any>[]
+    ) as Record<string, unknown>[]
 
     const itemNc = changes.find((nc) => nc.name === 'Item')!
     expect(itemNc.transform.m02).toBe(0)
@@ -193,7 +193,7 @@ describe('Fix 2: frameMaskDisabled is inverse of clipsContent', () => {
       height: 100
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].frameMaskDisabled).toBe(true)
   })
 
@@ -208,7 +208,7 @@ describe('Fix 2: frameMaskDisabled is inverse of clipsContent', () => {
       clipsContent: true
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].frameMaskDisabled).toBe(false)
   })
 
@@ -223,7 +223,7 @@ describe('Fix 2: frameMaskDisabled is inverse of clipsContent', () => {
       clipsContent: false
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].frameMaskDisabled).toBe(true)
   })
 
@@ -264,7 +264,7 @@ describe('Fix 3: bordersTakeSpace serialization', () => {
       strokesIncludedInLayout: true
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].bordersTakeSpace).toBe(true)
   })
 
@@ -281,7 +281,7 @@ describe('Fix 3: bordersTakeSpace serialization', () => {
       strokesIncludedInLayout: false
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].bordersTakeSpace).toBe(false)
   })
 
@@ -296,7 +296,7 @@ describe('Fix 3: bordersTakeSpace serialization', () => {
       strokesIncludedInLayout: true
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].bordersTakeSpace).toBeUndefined()
   })
 })
@@ -321,7 +321,7 @@ describe('Fix 4: text lineHeight serialization', () => {
       lineHeight: 24
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].lineHeight).toEqual({ value: 24, units: 'PIXELS' })
   })
 
@@ -340,7 +340,7 @@ describe('Fix 4: text lineHeight serialization', () => {
       // lineHeight not set — defaults to null
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     // ceil(16 * 1.2) = ceil(19.2) = 20
     expect(changes[0].lineHeight).toEqual({ value: 20, units: 'PIXELS' })
   })
@@ -359,7 +359,7 @@ describe('Fix 4: text lineHeight serialization', () => {
       fontSize: 14
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     // ceil(14 * 1.2) = ceil(16.8) = 17
     expect(changes[0].lineHeight).toEqual({ value: 17, units: 'PIXELS' })
   })
@@ -469,7 +469,7 @@ describe('Fix 5: font family normalization in derivedTextData', () => {
       fontSize: 14
     })
 
-    const changes = toKiwi(node, graph) as Record<string, any>[]
+    const changes = toKiwi(node, graph) as Record<string, unknown>[]
     expect(changes[0].fontName.family).toBe('DM Sans')
   })
 })
@@ -539,7 +539,7 @@ describe('Integration: auto-layout component with all fixes', () => {
       { value: 100 },
       graph,
       blobs
-    ) as Record<string, any>[]
+    ) as Record<string, unknown>[]
 
     const cardNc = changes[0]
     const titleNc = changes.find((nc) => nc.name === 'Title')!