feat: Adds provide to the global config.

Author: jeremyzahner

docs/en/api/config.md

@@ -60,3 +60,22 @@ VueTestUtils.config.methods['errors'] = () => {
   any: () => false
 }
 ```
+
+### `provide`
+
+- type: `Object`
+- default: `{}`
+
+Like `stubs` or `mocks`, the values passed to `config.provide` are used by default. Any values passed to the mounting options `provide` object will take priority over the ones declared in `config.provide`. **Please take note that it is not supported to pass a function as `config.provide`.**
+
+Example:
+
+```js
+import VueTestUtils from '@vue/test-utils'
+
+VueTestUtils.config.provide['$logger'] = {
+  log: (...args) => {
+    console.log(...args)
+  }
+}
+```

packages/shared/merge-options.js

@@ -3,15 +3,19 @@
 function getOptions (key, options, config) {
   if (options ||
     (config[key] && Object.keys(config[key]).length > 0)) {
-    if (Array.isArray(options)) {
+    if (options instanceof Function) {
+      return options
+    } else if (Array.isArray(options)) {
       return [
         ...options,
         ...Object.keys(config[key] || {})]
-    } else {
+    } else if (!(config[key] instanceof Function)) {
       return {
         ...config[key],
         ...options
       }
+    } else {
+      throw new Error(`Config can't be a Function.`)
     }
   }
 }
@@ -24,7 +28,8 @@ export function mergeOptions (
     ...options,
     stubs: getOptions('stubs', options.stubs, config),
     mocks: getOptions('mocks', options.mocks, config),
-    methods: getOptions('methods', options.methods, config)
+    methods: getOptions('methods', options.methods, config),
+    provide: getOptions('provide', options.provide, config)
   }
 }
 

packages/test-utils/src/config.js

@@ -7,5 +7,6 @@ export default {
     'transition-group': TransitionGroupStub
   },
   mocks: {},
-  methods: {}
+  methods: {},
+  provide: {}
 }

test/specs/mounting-options/provide.spec.js

@@ -1,3 +1,4 @@
+import { config } from '~vue/test-utils'
 import ComponentWithInject from '~resources/components/component-with-inject.vue'
 import { injectSupported } from '~resources/utils'
 import {
@@ -6,6 +7,17 @@ import {
 } from '~resources/utils'
 
 describeWithMountingMethods('options.provide', (mountingMethod) => {
+  let configProvideSave
+
+  beforeEach(() => {
+    configProvideSave = config.provide
+    config.provide = {}
+  })
+
+  afterEach(() => {
+    config.provide = configProvideSave
+  })
+
   itDoNotRunIf(!injectSupported(),
     'provides objects which is injected by mounted component', () => {
       if (!injectSupported()) return
@@ -44,4 +56,38 @@ describeWithMountingMethods('options.provide', (mountingMethod) => {
 
       expect(wrapper.vm.setInBeforeCreate).to.equal('created')
     })
+
+  it('injects the provide from the config', () => {
+    config.provide['fromMount'] = 'globalConfig'
+
+    const wrapper = mountingMethod(ComponentWithInject)
+    const HTML = mountingMethod.name === 'renderToString'
+      ? wrapper
+      : wrapper.html()
+
+    expect(HTML).to.contain('globalConfig')
+  })
+
+  it('prioritize mounting options over config', () => {
+    config.provide['fromMount'] = 'globalConfig'
+
+    const wrapper = mountingMethod(ComponentWithInject, {
+      provide: { fromMount: '_' }
+    })
+    const HTML = mountingMethod.name === 'renderToString'
+      ? wrapper
+      : wrapper.html()
+
+    expect(HTML).to.contain('_')
+  })
+
+  it('config with function throws', () => {
+    config.provide = () => {}
+
+    expect(() => {
+      mountingMethod(ComponentWithInject, {
+        provide: { fromMount: '_' }
+      })
+    }).to.throw()
+  })
 })