test: adjust tests

Fixes #1

test/Common.spec.ts

@@ -14,11 +14,15 @@
  */
 import {expect} from 'chai';
 import {slow, suite, test, timeout} from 'mocha-typescript';
-import {deleteUndefinedProperties} from '../src/common';
+import {
+  deleteUndefinedProperties,
+  isNodeEnvironment,
+  isProductiveEnvironment,
+  isProductiveNodeEnvironment,
+} from '../src/common';
 
 @suite(timeout(2000), slow(1000))
 export class CommonSpec {
-  /* tslint:disable:member-ordering */
   @test
   deleteUndefinedProperties1() {
     expect(deleteUndefinedProperties(
@@ -67,4 +71,48 @@ export class CommonSpec {
       },
     );
   }
+
+  @test
+  isNodeEnvironment() {
+    expect(isNodeEnvironment()).to.be.equal(true);
+
+    const savedProcess = process;
+
+    // @ts-ignore
+    process = undefined;
+
+    expect(isNodeEnvironment()).to.be.equal(false);
+
+    process = savedProcess;
+  }
+
+  @test
+  isProductiveEnvironment() {
+    const nodeEnv = process.env.NODE_ENV;
+
+    process.env.NODE_ENV = '';
+
+    expect(isProductiveEnvironment()).to.be.equal(false);
+
+    process.env.NODE_ENV = 'production';
+
+    expect(isProductiveEnvironment()).to.be.equal(true);
+
+    process.env.NODE_ENV = nodeEnv;
+  }
+
+  @test
+  isProductiveNodeEnvironment() {
+    const nodeEnv = process.env.NODE_ENV;
+
+    process.env.NODE_ENV = '';
+
+    expect(isProductiveNodeEnvironment()).to.be.equal(false);
+
+    process.env.NODE_ENV = 'production';
+
+    expect(isProductiveNodeEnvironment()).to.be.equal(true);
+
+    process.env.NODE_ENV = nodeEnv;
+  }
 }