test: improve coverage

packages/runtime-core/__tests__/rendererChildren.spec.ts

@@ -40,7 +40,7 @@ function shuffle(array: Array<any>) {
   return array
 }
 
-it('should patch previously empty children', () => {
+test('should patch previously empty children', () => {
   const root = nodeOps.createElement('div')
 
   render(h('div', []), root)
@@ -50,7 +50,7 @@ it('should patch previously empty children', () => {
   expect(inner(root)).toBe('<div>hello</div>')
 })
 
-it('should patch previously null children', () => {
+test('should patch previously null children', () => {
   const root = nodeOps.createElement('div')
 
   render(h('div'), root)
@@ -60,6 +60,15 @@ it('should patch previously null children', () => {
   expect(inner(root)).toBe('<div>hello</div>')
 })
 
+test('array children -> text children', () => {
+  const root = nodeOps.createElement('div')
+  render(h('div', [h('div')]), root)
+  expect(inner(root)).toBe('<div><div></div></div>')
+
+  render(h('div', 'hello'), root)
+  expect(inner(root)).toBe('<div>hello</div>')
+})
+
 describe('renderer: keyed children', () => {
   let root: TestElement
   let elm: TestElement

packages/runtime-core/__tests__/rendererFragment.spec.ts

@@ -129,6 +129,20 @@ describe('renderer: fragment', () => {
       root
     )
     expect(serializeInner(root)).toBe(`<div>foo</div>barbaz`)
+
+    render(
+      createVNode(
+        Fragment,
+        null,
+        [
+          createTextVNode('baz'),
+          createVNode('div', null, 'foo', PatchFlags.TEXT)
+        ],
+        PatchFlags.UNKEYED_FRAGMENT
+      ),
+      root
+    )
+    expect(serializeInner(root)).toBe(`baz<div>foo</div>`)
   })
 
   it('patch fragment children (compiler generated, keyed)', () => {

packages/runtime-core/src/component.ts

@@ -690,6 +690,7 @@ const classifyRE = /(?:^|[-_])(\w)/g
 const classify = (str: string): string =>
   str.replace(classifyRE, c => c.toUpperCase()).replace(/[-_]/g, '')
 
+/* istanbul ignore next */
 export function formatComponentName(
   instance: ComponentInternalInstance | null,
   Component: Component,

packages/runtime-core/src/warning.ts

@@ -57,6 +57,7 @@ export function warn(msg: string, ...args: any[]) {
     )
   } else {
     const warnArgs = [`[Vue warn]: ${msg}`, ...args]
+    /* istanbul ignore if */
     if (
       trace.length &&
       // avoid spamming console during tests
@@ -99,6 +100,7 @@ function getComponentTrace(): ComponentTraceStack {
   return normalizedStack
 }
 
+/* istanbul ignore next */
 function formatTrace(trace: ComponentTraceStack): any[] {
   const logs: any[] = []
   trace.forEach((entry, i) => {
@@ -122,6 +124,7 @@ function formatTraceEntry({ vnode, recurseCount }: TraceEntry): any[] {
     : [open + close]
 }
 
+/* istanbul ignore next */
 function formatProps(props: Data): any[] {
   const res: any[] = []
   const keys = Object.keys(props)
@@ -136,6 +139,7 @@ function formatProps(props: Data): any[] {
 
 function formatProp(key: string, value: unknown): any[]
 function formatProp(key: string, value: unknown, raw: true): any
+/* istanbul ignore next */
 function formatProp(key: string, value: unknown, raw?: boolean): any {
   if (isString(value)) {
     value = JSON.stringify(value)