From c496fe3b2689b843135b4de74651af2fdb625219 Mon Sep 17 00:00:00 2001
From: Robert Kawecki <robert+github@rkaw.pl>
Date: Mon, 16 Nov 2020 22:12:30 +0100
Subject: [PATCH] Rewrite 2 out of 3 Auction tests to use mockist testing

This changes how the tests work as an example of behavior verification,
as opposed to state verification. The third test is still not ported,
see: https://github.com/sinonjs/sinon/pull/1501
---
 code/in-search-of-a-unit/test/Auction.test.ts | 20 +++++++++++++++----
 code/package-lock.json                        | 15 ++++++++++++++
 code/package.json                             |  1 +
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/code/in-search-of-a-unit/test/Auction.test.ts b/code/in-search-of-a-unit/test/Auction.test.ts
index 5539a54..0a81743 100644
--- a/code/in-search-of-a-unit/test/Auction.test.ts
+++ b/code/in-search-of-a-unit/test/Auction.test.ts
@@ -4,6 +4,7 @@ import { Money } from "../src/Money";
 import * as uuid from 'uuid';
 import { Offer } from "../src/Offer";
 import * as assert from "assert";
+import * as sinon from "sinon";
 
 function testOffer(amount: number, currency = 'PLN', user?: string): Offer {
     return {
@@ -26,25 +27,36 @@ function stuffAuction(auction: Auction, count: number) {
 describe('Auction', function() {
     it('should immediately reject an offer that could not possibly win', async function() {
         const notifier = new EmailNotifier();
+        const mockNotifier = sinon.mock(notifier);
         const sale = new Auction('PLN', 5, notifier);
         // Initially, everybody goes into auction at 10 PLN:
         const initialOffers = stuffAuction(sale, 5);
         // Subsequent offers for the same amount should be rejected:
-        const sixthOfferResult = await sale.makeOffer(testOffer(10));
-        assert.strictEqual(sixthOfferResult, false);
+        const sixthOffer = testOffer(10);
+        mockNotifier.expects('notifyUser').once().withArgs(sixthOffer.madeByUserID, {
+            eventType: 'outbid',
+            offer: sixthOffer
+        }).resolves();
+        const sixthOfferResult = await sale.makeOffer(sixthOffer);
+        mockNotifier.verify();
     });
     it('should replace the last offer if a better one comes in', async function() {
         const notifier = new EmailNotifier();
+        const mockNotifier = sinon.mock(notifier);
         const sale = new Auction('PLN', 5, notifier);
         const initialOffers = stuffAuction(sale, 5);
         // A new offer should annul the last one made:
         const lastOffer = sale.getQualifyingOffers().pop()!;
         const betterOffer = testOffer(15);
+        mockNotifier.expects('notifyUser').once().withArgs(lastOffer.madeByUserID, {
+            eventType: 'outbid',
+            offer: lastOffer
+        }).resolves();
         await sale.makeOffer(betterOffer);
-        assert.ok(sale.getQualifyingOffers().includes(betterOffer));
-        assert.ok(!sale.getQualifyingOffers().includes(lastOffer));
+        mockNotifier.verify();
     });
     it('should select the winners after some offers are replaced', async function() {
+        // TODO: Rewrite this test to use behavior verification as well!
         const notifier = new EmailNotifier();
         const sale = new Auction('PLN', 5, notifier);
         const initialOffers = stuffAuction(sale, 5);
diff --git a/code/package-lock.json b/code/package-lock.json
index 021401b..113b742 100644
--- a/code/package-lock.json
+++ b/code/package-lock.json
@@ -62,6 +62,21 @@
       "integrity": "sha512-Zw1vhUSQZYw+7u5dAwNbIA9TuTotpzY/OF7sJM9FqPOF3SPjKnxrjoTktXDZgUjybf4cWVBP7O8wvKdSaGHweg==",
       "dev": true
     },
+    "@types/sinon": {
+      "version": "9.0.8",
+      "resolved": "https://registry.npmjs.org/@types/sinon/-/sinon-9.0.8.tgz",
+      "integrity": "sha512-IVnI820FZFMGI+u1R+2VdRaD/82YIQTdqLYC9DLPszZuynAJDtCvCtCs3bmyL66s7FqRM3+LPX7DhHnVTaagDw==",
+      "dev": true,
+      "requires": {
+        "@types/sinonjs__fake-timers": "*"
+      }
+    },
+    "@types/sinonjs__fake-timers": {
+      "version": "6.0.2",
+      "resolved": "https://registry.npmjs.org/@types/sinonjs__fake-timers/-/sinonjs__fake-timers-6.0.2.tgz",
+      "integrity": "sha512-dIPoZ3g5gcx9zZEszaxLSVTvMReD3xxyyDnQUjA6IYDG9Ba2AV0otMPs+77sG9ojB4Qr2N2Vk5RnKeuA0X/0bg==",
+      "dev": true
+    },
     "@types/uuid": {
       "version": "8.3.0",
       "resolved": "https://registry.npmjs.org/@types/uuid/-/uuid-8.3.0.tgz",
diff --git a/code/package.json b/code/package.json
index cf2cade..106ae5a 100644
--- a/code/package.json
+++ b/code/package.json
@@ -19,6 +19,7 @@
     "@types/big.js": "^6.0.0",
     "@types/mocha": "^8.0.4",
     "@types/node": "^14.14.7",
+    "@types/sinon": "^9.0.8",
     "@types/uuid": "^8.3.0",
     "ts-node": "^9.0.0",
     "typescript": "^4.0.5"