refactor(compiler): improve member expression check for v-on & v-model

packages/compiler-core/__tests__/transforms/vModel.spec.ts

@@ -351,5 +351,17 @@ describe('compiler: transform v-model', () => {
         })
       )
     })
+
+    test('mal-formed expression', () => {
+      const onError = jest.fn()
+      parseWithVModel('<span v-model="a + b" />', { onError })
+
+      expect(onError).toHaveBeenCalledTimes(1)
+      expect(onError).toHaveBeenCalledWith(
+        expect.objectContaining({
+          code: ErrorCodes.X_V_MODEL_MALFORMED_EXPRESSION
+        })
+      )
+    })
   })
 })

packages/compiler-core/__tests__/transforms/vOn.spec.ts

@@ -175,6 +175,34 @@ describe('compiler: transform v-on', () => {
     })
   })
 
+  test('should NOT wrap as function if expression is complex member expression', () => {
+    const node = parseWithVOn(`<div @click="a['b' + c]"/>`)
+    const props = (node.codegenNode as CallExpression)
+      .arguments[1] as ObjectExpression
+    expect(props.properties[0]).toMatchObject({
+      key: { content: `onClick` },
+      value: {
+        type: NodeTypes.SIMPLE_EXPRESSION,
+        content: `a['b' + c]`
+      }
+    })
+  })
+
+  test('complex member expression w/ prefixIdentifiers: true', () => {
+    const node = parseWithVOn(`<div @click="a['b' + c]"/>`, {
+      prefixIdentifiers: true
+    })
+    const props = (node.codegenNode as CallExpression)
+      .arguments[1] as ObjectExpression
+    expect(props.properties[0]).toMatchObject({
+      key: { content: `onClick` },
+      value: {
+        type: NodeTypes.COMPOUND_EXPRESSION,
+        children: [{ content: `_ctx.a` }, `['b' + `, { content: `_ctx.c` }, `]`]
+      }
+    })
+  })
+
   test('function expression w/ prefixIdentifiers: true', () => {
     const node = parseWithVOn(`<div @click="e => foo(e)"/>`, {
       prefixIdentifiers: true