Tests for AuthFlow.handleRequest callback arg

src/services/authFlow/AuthFlow.js

@@ -82,13 +82,25 @@ export default class AuthFlow {
         if (resp && resp.then) {
             // this is a state with an async enter phase
             // block route components from mounting, till promise will be resolved
-            const callback = this.onReady;
-            this.onReady = () => {};
-            return resp.then(callback);
+            if (this.onReady) {
+                const callback = this.onReady;
+                this.onReady = () => {};
+                return resp.then(callback);
+            } else {
+                return resp;
+            }
         }
     }
 
-    handleRequest(path, replace, callback) {
+    /**
+     * This should be called from onEnter prop of react-router Route component
+     *
+     * @param {string} path
+     * @param {function} replace
+     * @param {function} [callback = function() {}] - an optional callback function to be called, when state will be stabilized
+     *                                                (state's enter function's promise resolved)
+     */
+    handleRequest(path, replace, callback = function() {}) {
         this.replace = replace;
         this.onReady = callback;
 

tests/services/authFlow/AuthFlow.test.js

@@ -38,7 +38,7 @@ describe('AuthFlow', () => {
             expect(flow.state).to.be.equal(state);
         });
 
-        it('should call `enter` on new state and pass reference to itself', () => {
+        it('should call #enter() on new state and pass reference to itself', () => {
             const state = new AbstractState();
             const spy = sinon.spy(state, 'enter');
 
@@ -62,6 +62,17 @@ describe('AuthFlow', () => {
             sinon.assert.notCalled(spy2);
         });
 
+        it('should return promise, if #enter returns it', () => {
+            const state = new AbstractState();
+            const expected = Promise.resolve();
+
+            state.enter = () => expected;
+
+            const actual = flow.setState(state);
+
+            expect(actual).to.be.equal(expected);
+        });
+
         it('should throw if no state', () => {
             expect(() => flow.setState()).to.throw('State is required');
         });
@@ -184,6 +195,32 @@ describe('AuthFlow', () => {
             sinon.assert.calledWithExactly(flow.run, 'setOAuthRequest', {});
         });
 
+        it('should call callback', () => {
+            const callback = sinon.stub();
+
+            flow.handleRequest('/', function() {}, callback);
+
+            sinon.assert.calledOnce(callback);
+        });
+
+        it('should not call callback till returned from #enter() promise will be resolved', () => {
+            let resolve;
+            const promise = {then: (cb) => {resolve = cb}};
+            const callback = sinon.stub();
+            const state = new AbstractState();
+            state.enter = () => promise;
+
+            flow.setState = AuthFlow.prototype.setState.bind(flow, state);
+
+            flow.handleRequest('/', function() {}, callback);
+
+            expect(resolve).to.be.a('function');
+
+            sinon.assert.notCalled(callback);
+            resolve();
+            sinon.assert.calledOnce(callback);
+        });
+
         it('throws if unsupported request', () => {
             expect(() => flow.handleRequest('/foo/bar')).to.throw('Unsupported request: /foo/bar');
         });