wip: exclude legacy slots from $scopedSlots

packages/compiler-core/src/ast.ts

@@ -352,6 +352,11 @@ export interface FunctionExpression extends Node {
    * withScopeId() wrapper
    */
   isSlot: boolean
+  /**
+   * __COMPAT__ only, indicates a slot function that should be excluded from
+   * the legacy $scopedSlots instance property.
+   */
+  isNonScopedSlot?: boolean
 }
 
 export interface ConditionalExpression extends Node {

packages/compiler-core/src/codegen.ts

@@ -878,6 +878,9 @@ function genFunctionExpression(
     push(`}`)
   }
   if (isSlot) {
+    if (__COMPAT__ && node.isNonScopedSlot) {
+      push(`, undefined, true`)
+    }
     push(`)`)
   }
 }

packages/compiler-core/src/transforms/vSlot.ts

@@ -129,11 +129,6 @@ export function buildSlots(
   const slotsProperties: Property[] = []
   const dynamicSlots: (ConditionalExpression | CallExpression)[] = []
 
-  const buildDefaultSlotProperty = (
-    props: ExpressionNode | undefined,
-    children: TemplateChildNode[]
-  ) => createObjectProperty(`default`, buildSlotFn(props, children, loc))
-
   // If the slot is inside a v-for or another v-slot, force it to be dynamic
   // since it likely uses a scope variable.
   let hasDynamicSlots = context.scopes.vSlot > 0 || context.scopes.vFor > 0
@@ -302,6 +297,17 @@ export function buildSlots(
   }
 
   if (!onComponentSlot) {
+    const buildDefaultSlotProperty = (
+      props: ExpressionNode | undefined,
+      children: TemplateChildNode[]
+    ) => {
+      const fn = buildSlotFn(props, children, loc)
+      if (__COMPAT__) {
+        fn.isNonScopedSlot = true
+      }
+      return createObjectProperty(`default`, fn)
+    }
+
     if (!hasTemplateSlots) {
       // implicit default slot (on component)
       slotsProperties.push(buildDefaultSlotProperty(undefined, children))