test: improve coverage

packages/runtime-dom/__tests__/helpers/useCssModule.spec.ts

@@ -0,0 +1,55 @@
+import { render, h, nodeOps } from '@vue/runtime-test'
+import { useCssModule } from '../../src/helpers/useCssModule'
+import { mockWarn } from '@vue/shared'
+
+describe('useCssModule', () => {
+  mockWarn()
+
+  function mountWithModule(modules: any, name?: string) {
+    let res
+    render(
+      h({
+        render() {},
+        __cssModules: modules,
+        setup() {
+          res = useCssModule(name)
+        }
+      }),
+      nodeOps.createElement('div')
+    )
+    return res
+  }
+
+  test('basic usage', () => {
+    const modules = {
+      $style: {
+        red: 'red'
+      }
+    }
+    expect(mountWithModule(modules)).toMatchObject(modules.$style)
+  })
+
+  test('basic usage', () => {
+    const modules = {
+      foo: {
+        red: 'red'
+      }
+    }
+    expect(mountWithModule(modules, 'foo')).toMatchObject(modules.foo)
+  })
+
+  test('warn out of setup usage', () => {
+    useCssModule()
+    expect('must be called inside setup').toHaveBeenWarned()
+  })
+
+  test('warn missing injection', () => {
+    mountWithModule(undefined)
+    expect('instance does not have CSS modules').toHaveBeenWarned()
+  })
+
+  test('warn missing injection', () => {
+    mountWithModule({ $style: { red: 'red' } }, 'foo')
+    expect('instance does not have CSS module named "foo"').toHaveBeenWarned()
+  })
+})

packages/runtime-dom/src/helpers/useCssModule.ts

@@ -2,10 +2,11 @@ import { warn, getCurrentInstance } from '@vue/runtime-core'
 import { EMPTY_OBJ } from '@vue/shared'
 
 export function useCssModule(name = '$style'): Record<string, string> {
+  /* istanbul ignore else */
   if (!__GLOBAL__) {
     const instance = getCurrentInstance()!
     if (!instance) {
-      __DEV__ && warn(`useCSSModule must be called inside setup()`)
+      __DEV__ && warn(`useCssModule must be called inside setup()`)
       return EMPTY_OBJ
     }
     const modules = instance.type.__cssModules
@@ -22,7 +23,7 @@ export function useCssModule(name = '$style'): Record<string, string> {
     return mod as Record<string, string>
   } else {
     if (__DEV__) {
-      warn(`useCSSModule() is not supported in the global build.`)
+      warn(`useCssModule() is not supported in the global build.`)
     }
     return EMPTY_OBJ
   }

packages/runtime-dom/src/helpers/useCssVars.ts

@@ -14,6 +14,7 @@ export function useCssVars(
   scoped = false
 ) {
   const instance = getCurrentInstance()
+  /* istanbul ignore next */
   if (!instance) {
     __DEV__ &&
       warn(`useCssVars is called without current active component instance.`)