[base] Expose client as CommonJS (#133)

packages/@sanity/base/package.json

@@ -44,6 +44,7 @@
   },
   "devDependencies": {
     "@sanity/check": "^0.108.0",
+    "@sanity/plugin-loader": "^0.108.0",
     "chai": "^3.5.0",
     "chai-as-promised": "^6.0.0",
     "eslint": "^3.19.0",

packages/@sanity/base/src/client/index.js

@@ -2,7 +2,30 @@ import sanityClient from '@sanity/client'
 import config from 'config:sanity'
 import configureClient from 'part:@sanity/base/configure-client?'
 
+const deprecationMessage = `[deprecation] The Sanity client is now exposed in CommonJS format.
+
+For instance, change:
+  \`const client = require('part:@sanity/base/client').default\`
+
+To the following:
+  \`const client = require('part:@sanity/base/client')\`
+`
+
 const apiConfig = {...config.api, withCredentials: true}
 const client = sanityClient(apiConfig)
 
-export default configureClient ? configureClient(sanityClient(apiConfig)) : client
+const configuredClient = configureClient
+  ? configureClient(sanityClient(apiConfig))
+  : client
+
+// Warn when people use `.default`
+Object.defineProperty(configuredClient, 'default', {
+  get() {
+    // eslint-disable-next-line no-console
+    console.warn(deprecationMessage)
+    return configuredClient
+  }
+})
+
+// Expose as CJS to allow Node scripts to consume it without `.default`
+module.exports = configuredClient

packages/@sanity/base/test/client.test.js

@@ -0,0 +1,15 @@
+import {describe, it} from 'mocha'
+import {expect} from 'chai'
+import client from '../src/client'
+
+describe('client', () => {
+  it('should be exposed in CommonJS format', done => {
+    expect(client.fetch).to.be.a('function')
+    done()
+  })
+
+  it('should still expose client on .default, but give warning', done => {
+    expect(client.default.fetch).to.be.a('function')
+    done()
+  })
+})

packages/@sanity/base/test/init.js

@@ -1,5 +1,12 @@
 import chai from 'chai'
 import chaiAsPromised from 'chai-as-promised'
+import pluginLoader from '@sanity/plugin-loader'
+
+pluginLoader({
+  overrides: {
+    'config:sanity': [{api: {projectId: 'abc123', dataset: 'hei'}}]
+  }
+})
 
 chai.should()
 chai.use(chaiAsPromised)