hopefully fix unit test

Author: ejizba

test/eventHandlers/FunctionEnvironmentReloadHandler.test.ts

@@ -6,6 +6,7 @@ import 'mocha';
 import * as mock from 'mock-fs';
 import { AzureFunctionsRpcMessages as rpc } from '../../azure-functions-language-worker-protobuf/src/rpc';
 import { WorkerChannel } from '../../src/WorkerChannel';
+import { resetProcessEnv } from '../utils/resetProcessEnv';
 import { beforeEventHandlerSuite } from './beforeEventHandlerSuite';
 import { TestEventStream } from './TestEventStream';
 import { Msg as WorkerInitMsg } from './WorkerInitHandler.test';
@@ -81,7 +82,7 @@ describe('FunctionEnvironmentReloadHandler', () => {
     });
 
     after(() => {
-        Object.assign(process.env, originalEnv);
+        resetProcessEnv(originalEnv);
     });
 
     afterEach(async () => {

test/eventHandlers/WorkerInitHandler.test.ts

@@ -9,6 +9,7 @@ import * as mockFs from 'mock-fs';
 import { AzureFunctionsRpcMessages as rpc } from '../../azure-functions-language-worker-protobuf/src/rpc';
 import { logColdStartWarning } from '../../src/eventHandlers/WorkerInitHandler';
 import { WorkerChannel } from '../../src/WorkerChannel';
+import { resetProcessEnv } from '../utils/resetProcessEnv';
 import { beforeEventHandlerSuite } from './beforeEventHandlerSuite';
 import { RegExpStreamingMessage, TestEventStream } from './TestEventStream';
 import path = require('path');
@@ -140,11 +141,17 @@ export namespace Msg {
 describe('WorkerInitHandler', () => {
     let channel: WorkerChannel;
     let stream: TestEventStream;
+    let originalEnv: NodeJS.ProcessEnv;
 
     before(() => {
+        originalEnv = { ...process.env };
         ({ stream, channel } = beforeEventHandlerSuite());
     });
 
+    after(() => {
+        resetProcessEnv(originalEnv);
+    });
+
     afterEach(async () => {
         mockFs.restore();
         await stream.afterEachEventHandlerTest();

test/startApp.test.ts

@@ -10,6 +10,7 @@ import { beforeEventHandlerSuite } from './eventHandlers/beforeEventHandlerSuite
 import { Msg as EnvReloadMsg } from './eventHandlers/FunctionEnvironmentReloadHandler.test';
 import { TestEventStream } from './eventHandlers/TestEventStream';
 import { Msg as WorkerInitMsg } from './eventHandlers/WorkerInitHandler.test';
+import { resetProcessEnv } from './utils/resetProcessEnv';
 import LogCategory = rpc.RpcLog.RpcLogCategory;
 import LogLevel = rpc.RpcLog.Level;
 
@@ -54,7 +55,7 @@ describe('startApp', () => {
     });
 
     after(() => {
-        Object.assign(process.env, originalEnv);
+        resetProcessEnv(originalEnv);
     });
 
     afterEach(async () => {

test/utils/resetProcessEnv.ts

@@ -0,0 +1,11 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License.
+
+export function resetProcessEnv(originalEnv: NodeJS.ProcessEnv): void {
+    for (const key of Object.keys(process.env)) {
+        if (!(key in originalEnv)) {
+            delete process.env[key];
+        }
+    }
+    Object.assign(process.env, originalEnv);
+}