feat: update to support babel config bool/string/object

Author: Justin Helmer

README.md

@@ -57,7 +57,15 @@ vue-jest compiles the script and template of SFCs into a JavaScript file that Je
 - **typescript** (`lang="ts"`, `lang="typescript"`)
 - **coffeescript** (`lang="coffee"`, `lang="coffeescript"`)
 
-To define a tsconfig file that vue-jest will use when transpiling typescript, you can specify it in the jest globals
+### Global Jest options
+
+You can change the behavior of `vue-jest` by using `jest.globals`.
+
+> *Tip:* Need programmatic configuration? Use the [--config](https://jestjs.io/docs/en/cli.html#config-path) option in Jest CLI, and export a `.js` file
+
+#### tsConfigFile
+
+Provide a path to a `tsconfig` file that `vue-jest` will use when transpiling typescript:
 
 ```json
 {
@@ -71,7 +79,9 @@ To define a tsconfig file that vue-jest will use when transpiling typescript, yo
 }
 ```
 
-To define a babelrc file that vue-jest will use when transpiling javascript, you can specify it in the jest globals
+#### babelRcFile
+
+Provide a path to a `.babelrc` file that `vue-jest` will use when transpiling javascript:
 
 ```json
 {
@@ -85,6 +95,105 @@ To define a babelrc file that vue-jest will use when transpiling javascript, you
 }
 ```
 
+#### babelConfig
+
+Provide `babelConfig` in one of the following formats:
+
+- `<Boolean>`
+- `<Object>`
+- `<String>`
+
+##### Boolean
+
+- `true` - Enable Babel processing. `vue-jest` will try to find babel configuration using [find-babel-config](https://www.npmjs.com/package/find-babel-config).
+
+> This is the default behavior if [babelRcFile](#babelrcfile) and [babelConfig](#babelconfig) are both undefined.
+
+- `false` - Skip Babel processing entirely:
+
+```json
+{
+  "jest": {
+    "globals": {
+      "vue-jest": {
+        "babelConfig": false
+      }
+    }
+  }
+}
+```
+
+##### Object
+
+Provide inline [Babel options](https://babeljs.io/docs/en/options):
+
+```json
+{
+  "jest": {
+    "globals": {
+      "vue-jest": {
+        "babelConfig": {
+          "presets": [
+            [
+              "env",
+              {
+                "useBuiltIns": "entry",
+                "shippedProposals": true
+              }
+            ]
+          ],
+          "plugins": [
+            "syntax-dynamic-import"
+          ],
+          "env": {
+            "test": {
+              "plugins": [
+                "dynamic-import-node"
+              ]
+            }
+          }
+        }
+      }
+    }
+  }
+}
+```
+
+##### String
+
+If a string is provided, it will be an assumed path to a babel configuration file.
+- This is similar to the [babelRcFile](#babelrcfile) option, except it also allows for `.js` files (i.e. `.babelrc.js`).
+- Config file should export a Babel configuration object.
+- Should *not* point to a [project-wide configuration file (babel.config.js)](https://babeljs.io/docs/en/config-files#project-wide-configuration), which exports a function.
+
+```json
+{
+  "jest": {
+    "globals": {
+      "vue-jest": {
+        "babelConfig": "path/to/.babelrc.js"
+      }
+    }
+  }
+}
+```
+
+To use the [Config Function API](https://babeljs.io/docs/en/config-files#config-function-api), use inline options instead. i.e.:
+
+```json
+{
+  "jest": {
+    "globals": {
+      "vue-jest": {
+        "babelConfig": {
+          "configFile": "path/to/babel.config.js"
+        }
+      }
+    }
+  }
+}
+```
+
 ### Supported template languages
 
 - **pug** (`lang="pug"`)

lib/load-babel-config.js

@@ -4,6 +4,18 @@ const cache = require('./cache')
 const path = require('path')
 const { readFileSync, existsSync } = require('fs')
 
+const find = () => {
+  const { file, config } = findBabelConfig.sync(process.cwd(), 0)
+
+  if (!file) {
+    logger.info('no .babelrc found, skipping babel compilation')
+    cache.set('babel-config', false)
+    return
+  }
+
+  return config
+}
+
 module.exports = function getBabelConfig (vueJestConfig) {
   const cachedConfig = cache.get('babel-config')
   if (cachedConfig) {
@@ -17,19 +29,31 @@ module.exports = function getBabelConfig (vueJestConfig) {
       babelConfig = JSON.parse(readFileSync(vueJestConfig.babelRcFile))
     } else if (existsSync('babel.config.js')) {
       babelConfig = require(path.resolve('babel.config.js'))
-    } else {
-      const { file, config } = findBabelConfig.sync(process.cwd(), 0)
-
-      if (!file) {
-        logger.info('no .babelrc found, skipping babel compilation')
-        cache.set('babel-config', false)
-        return
+    } else if (vueJestConfig.hasOwnProperty('babelConfig')) {
+      switch (typeof vueJestConfig.babelConfig) {
+        case 'string':
+          // a path to a config file is being passed in; load it
+          babelConfig = require(vueJestConfig.babelConfig)
+          break
+        case 'boolean':
+          if (vueJestConfig.babelConfig === true) {
+            // console.log('sync', findBabelConfig.sync)
+            babelConfig = find()
+          }
+          break
+        case 'object':
+        default:
+          babelConfig = vueJestConfig.babelConfig
+          break
       }
+    } else {
+      babelConfig = find()
+    }
 
-      babelConfig = config
+    if (babelConfig) {
+      cache.set('babel-config', babelConfig)
     }
 
-    cache.set('babel-config', babelConfig)
     return babelConfig
   }
 }

test/load-babel-config.spec.js

@@ -1,3 +1,4 @@
+import findBabelConfig from 'find-babel-config'
 import loadBabelConfig from '../lib/load-babel-config'
 import { resolve } from 'path'
 import {
@@ -75,4 +76,54 @@ describe('load-babel-config.js', () => {
     expect(babelConfig).toEqual(config)
     unlinkSync(babelConfigPath)
   })
+
+  describe('babelConfig option', () => {
+    it('supports a path to a babel configuration file', () => {
+      const babelConfigPath = resolve(__dirname, '../some-babel-config.js')
+      const config = {
+        plugins: ['foo']
+      }
+      writeFileSync(babelConfigPath, `module.exports = ${JSON.stringify(config)}`)
+      const babelConfig = loadBabelConfig({
+        babelConfig: babelConfigPath
+      })
+      expect(babelConfig).toEqual(config)
+    })
+
+    it('supports a boolean indicating whether or not to search for babel config', () => {
+      const config = {
+        plugins: ['foo']
+      }
+      findBabelConfig.sync = jest.fn(() => ({ file: true, config }))
+      const noBabelConfig = loadBabelConfig({
+        babelConfig: false
+      })
+      expect(findBabelConfig.sync).not.toHaveBeenCalled()
+      expect(noBabelConfig).toBeUndefined()
+
+      const babelConfig = loadBabelConfig({
+        babelConfig: true
+      })
+      expect(findBabelConfig.sync).toHaveBeenCalled()
+      expect(babelConfig).toEqual(config)
+      findBabelConfig.sync.mockRestore()
+    })
+
+    it('supports a babel configuration object', () => {
+      const config = {
+        plugins: ['foo']
+      }
+      const babelConfig = loadBabelConfig({
+        babelConfig: config
+      })
+      expect(babelConfig).toEqual(config)
+    })
+
+    it('defaults to searching for babel config if option is not provided', () => {
+      findBabelConfig.sync = jest.fn(() => ({}))
+      loadBabelConfig({})
+      expect(findBabelConfig.sync).toHaveBeenCalled()
+      findBabelConfig.sync.mockRestore()
+    })
+  })
 })