deprecate: remove callback in module definition

lib/core/module.js

@@ -138,32 +138,16 @@ module.exports = class ModuleContainer {
     }
 
     return new Promise((resolve, reject) => {
-      // Prepare callback
-      const cb = err => {
-        printWarn(
-          'Supporting callbacks is deprecated and will be removed in next releases. Consider using async/await.',
-          src
-        )
-
-        /* istanbul ignore if */
-        if (err) {
-          return reject(err)
-        }
-        resolve()
-      }
-
       // Call module with `this` context and pass options
-      const result = handler.call(this, options, cb)
+      const result = handler.call(this, options)
 
       // If module send back a promise
       if (result && result.then) {
         return resolve(result)
       }
 
-      // If not expecting a callback but returns no promise (=synchronous)
-      if (handler.length < 2) {
+      // synchronous
       return resolve()
-      }
     })
   }
 }

test/deprecate.test.js

@@ -31,14 +31,6 @@ test.serial('Deprecated: module.addVendor()', async t => {
   t.true(buildSpies.warn.calledWithMatch('module: addVendor is no longer necessary'))
 })
 
-test.serial('Deprecated: module callback', async t => {
-  t.true(
-    buildSpies.warn.calledWithMatch(
-      'Supporting callbacks is deprecated and will be removed in next releases. Consider using async/await.'
-    )
-  )
-})
-
 // Close server and ask nuxt to stop listening to file changes
 test.after.always('Closing server and nuxt.js', async t => {
   await nuxt.close()

test/fixtures/deprecate/modules/deprecated-apis/index.js

@@ -1,4 +1,3 @@
 module.exports = function basicModule(options, resolve) {
   this.addVendor('lodash')
-  resolve()
 }