test: test scopeId support

packages/runtime-core/__tests__/helpers/scopeId.spec.ts

@@ -0,0 +1,47 @@
+import { withScopeId } from '../../src/helpers/scopeId'
+import { h, render, nodeOps, serializeInner } from '@vue/runtime-test'
+
+describe('scopeId runtime support', () => {
+  const withParentId = withScopeId('parent')
+  const withChildId = withScopeId('child')
+
+  test('should attach scopeId', () => {
+    const App = {
+      __scopeId: 'parent',
+      render: withParentId(() => {
+        return h('div', [h('div')])
+      })
+    }
+    const root = nodeOps.createElement('div')
+    render(h(App), root)
+    expect(serializeInner(root)).toBe(`<div parent><div parent></div></div>`)
+  })
+
+  test('should work on slots', () => {
+    const Child = {
+      __scopeId: 'child',
+      render: withChildId(function(this: any) {
+        return h('div', this.$slots.default())
+      })
+    }
+    const App = {
+      __scopeId: 'parent',
+      render: withParentId(() => {
+        return h(
+          Child,
+          withParentId(() => {
+            return h('div')
+          })
+        )
+      })
+    }
+    const root = nodeOps.createElement('div')
+    render(h(App), root)
+    // slot content should have:
+    // - scopeId from parent
+    // - slotted scopeId (with `-s` postfix) from child (the tree owner)
+    expect(serializeInner(root)).toBe(
+      `<div child><div parent child-s></div></div>`
+    )
+  })
+})