Added exception for null kubectl commands

lib/kubectl-object-model.js

@@ -1,9 +1,10 @@
 "use strict";
-var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {    
+var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
+    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
     return new (P || (P = Promise))(function (resolve, reject) {
         function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
         function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
-        function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
+        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
         step((generator = generator.apply(thisArg, _arguments || [])).next());
     });
 };
@@ -72,6 +73,8 @@ class Kubectl {
         return results;
     }
     executeCommand(customCommand, args) {
+        if (!customCommand)
+            throw new Error('NullCommandForKubectl');
         return args ? this.execute([customCommand, args]) : this.execute([customCommand]);
     }
     delete(args) {

lib/utilities/kubectl-util.js

@@ -74,7 +74,7 @@ exports.downloadKubectl = downloadKubectl;
 function getTrafficSplitAPIVersion(kubectl) {
     const result = kubectl.executeCommand('api-versions');
     const trafficSplitAPIVersion = result.stdout.split('\n').find(version => version.startsWith(trafficSplitAPIVersionPrefix));
-    if (trafficSplitAPIVersion == null || typeof trafficSplitAPIVersion == 'undefined') {
+    if (!trafficSplitAPIVersion) {
         throw new Error('UnableToCreateTrafficSplitManifestFile');
     }
     return trafficSplitAPIVersion;

src/kubectl-object-model.ts

@@ -80,6 +80,8 @@ export class Kubectl {
     }
 
     public executeCommand(customCommand: string, args?: string) {
+        if(!customCommand)
+            throw new Error('NullCommandForKubectl');
         return args ? this.execute([customCommand, args]) : this.execute([customCommand]);
     }
 

src/utilities/kubectl-util.ts

@@ -69,7 +69,7 @@ export async function downloadKubectl(version: string): Promise<string> {
 export function getTrafficSplitAPIVersion(kubectl: Kubectl): string {
     const result = kubectl.executeCommand('api-versions');
     const trafficSplitAPIVersion = result.stdout.split('\n').find(version => version.startsWith(trafficSplitAPIVersionPrefix));
-    if (trafficSplitAPIVersion == null || typeof trafficSplitAPIVersion == 'undefined') {
+    if (!trafficSplitAPIVersion) {
         throw new Error('UnableToCreateTrafficSplitManifestFile');
     }