feat(Brain): ensure User objects are actually User objects

Author: mistydemeo

src/brain.js

@@ -4,6 +4,28 @@ const EventEmitter = require('events').EventEmitter
 
 const User = require('./user')
 
+// If necessary, reconstructs a User object. Returns either:
+//
+// 1. If the original object was falsy, null
+// 2. If the original object was a User object, the original object
+// 3. If the original object was a plain JavaScript object, return
+//    a User object with all of the original object's properties.
+let reconstructUserIfNecessary = function (user) {
+  if (!user) {
+    return null
+  }
+
+  if (!user.constructor || (user.constructor && user.constructor.name !== 'User')) {
+    let id = user.id
+    delete user.id
+    // Use the old user as the "options" object,
+    // populating the new user with its values.
+    return new User(id, user)
+  } else {
+    return user
+  }
+}
+
 class Brain extends EventEmitter {
   // Represents somewhat persistent storage for the robot. Extend this.
   //
@@ -116,6 +138,14 @@ class Brain extends EventEmitter {
       this.data[k] = data[k]
     }
 
+    // Ensure users in the brain are still User objects.
+    if (data && data.users) {
+      for (let k in data.users) {
+        let user = this.data.users[k]
+        this.data.users[k] = reconstructUserIfNecessary(user)
+      }
+    }
+
     this.emit('loaded', this.data)
   }
 

test/brain_test.js

@@ -58,6 +58,14 @@ describe('Brain', function () {
         this.brain.mergeData({})
         expect(this.brain.emit).to.have.been.calledWith('loaded', this.brain.data)
       })
+
+      it('coerces loaded data into User objects', function () {
+        this.brain.mergeData({users: {'4': {'name': 'new', 'id': '4'}}})
+        let user = this.brain.userForId('4')
+        expect(user.constructor.name).to.equal('User')
+        expect(user.id).to.equal('4')
+        expect(user.name).to.equal('new')
+      })
     })
 
     describe('#save', () => it('emits a save event', function () {
@@ -308,5 +316,16 @@ describe('Brain', function () {
       expect(result).to.have.members([this.user1, this.user2])
       expect(result).to.not.have.members([this.user3])
     })
+
+    it('returns User objects, not POJOs', function () {
+      expect(this.brain.userForId('1').constructor.name).to.equal('User')
+      for (let user of this.brain.usersForFuzzyName('Guy')) {
+        expect(user.constructor.name).to.equal('User')
+      }
+
+      for (let user of this.brain.usersForRawFuzzyName('Guy One')) {
+        expect(user.constructor.name).to.equal('User')
+      }
+    })
   })
 })