From 177b66d1bf637ccd715a30aa150807afe96c34eb Mon Sep 17 00:00:00 2001
From: Filip Maj <fmaj@slack-corp.com>
Date: Tue, 20 Jul 2021 12:30:32 -0400
Subject: [PATCH] Add basic test for SocketModeReceiver constructor (#750)

---
 src/receivers/SocketModeReceiver.spec.ts | 113 +++++++++++++++++++++++
 1 file changed, 113 insertions(+)
 create mode 100644 src/receivers/SocketModeReceiver.spec.ts

diff --git a/src/receivers/SocketModeReceiver.spec.ts b/src/receivers/SocketModeReceiver.spec.ts
new file mode 100644
index 000000000..62b9a274d
--- /dev/null
+++ b/src/receivers/SocketModeReceiver.spec.ts
@@ -0,0 +1,113 @@
+/* eslint-disable @typescript-eslint/no-unsafe-call, @typescript-eslint/naming-convention */
+
+import 'mocha';
+import sinon, { SinonSpy } from 'sinon';
+import { assert } from 'chai';
+import { Override, mergeOverrides } from '../test-helpers';
+import rewiremock from 'rewiremock';
+import { Logger, LogLevel } from '@slack/logger';
+import { EventEmitter } from 'events';
+
+describe('SocketModeReceiver', function () {
+  const noopLogger: Logger = {
+    debug(..._msg: any[]): void {
+      /* noop */
+    },
+    info(..._msg: any[]): void {
+      /* noop */
+    },
+    warn(..._msg: any[]): void {
+      /* noop */
+    },
+    error(..._msg: any[]): void {
+      /* noop */
+    },
+    setLevel(_level: LogLevel): void {
+      /* noop */
+    },
+    getLevel(): LogLevel {
+      return LogLevel.DEBUG;
+    },
+    setName(_name: string): void {
+      /* noop */
+    },
+  };
+
+  describe('constructor', () => {
+    // NOTE: it would be more informative to test known valid combinations of options, as well as invalid combinations
+    it('should accept supported arguments and use default arguments when not provided', async () => {
+      // Arrange
+      const fakeServer = new FakeServer();
+      const fakeCreateServer = sinon.fake.returns(fakeServer);
+      const overrides = mergeOverrides(
+        withHttpCreateServer(fakeCreateServer),
+        withHttpsCreateServer(sinon.fake.throws('Should not be used.')),
+      );
+      const SocketModeReceiver = await importSocketModeReceiver(overrides);
+
+      const receiver = new SocketModeReceiver({
+        appToken: 'my-secret',
+        logger: noopLogger,
+        clientId: 'my-clientId',
+        clientSecret: 'my-client-secret',
+        stateSecret: 'state-secret',
+        scopes: ['channels:read'],
+        installerOptions: {
+          authVersion: 'v2',
+          userScopes: ['chat:write'],
+        },
+      });
+      assert.isNotNull(receiver);
+      assert.isOk(fakeServer.listen.calledWith(3000));
+    });
+  });
+});
+
+/* Testing Harness */
+
+// Loading the system under test using overrides
+async function importSocketModeReceiver(
+  overrides: Override = {},
+): Promise<typeof import('./SocketModeReceiver').default> {
+  return (await rewiremock.module(() => import('./SocketModeReceiver'), overrides)).default;
+}
+
+// Composable overrides
+function withHttpCreateServer(spy: SinonSpy): Override {
+  return {
+    http: {
+      createServer: spy,
+    },
+  };
+}
+
+function withHttpsCreateServer(spy: SinonSpy): Override {
+  return {
+    https: {
+      createServer: spy,
+    },
+  };
+}
+
+// Fakes
+class FakeServer extends EventEmitter {
+  public on = sinon.fake();
+  public listen = sinon.fake(() => {
+    if (this.listeningFailure !== undefined) {
+      this.emit('error', this.listeningFailure);
+      return;
+    }
+  });
+  public close = sinon.fake((...args: any[]) => {
+    setImmediate(() => {
+      this.emit('close');
+      setImmediate(() => {
+        args[0]();
+      });
+    });
+  });
+
+  constructor(private listeningFailure?: Error) {
+    super();
+  }
+}