Merge pull request Azure#5716 from sergey-shandar/sergey-vhd-fix

Fix VHD test Azure#5692

Author: cormacpayne

src/ResourceManager/Compute/Commands.Compute.Test/ScenarioTests/NewVhdVMTests.cs

@@ -25,8 +25,8 @@ public NewVhdVMTests(Xunit.Abstractions.ITestOutputHelper output)
             XunitTracingInterceptor.AddToContext(new XunitTracingInterceptor(output));
         }
 
-        [Fact(Skip = "Skip until necessary fixes done: https://github.com/Azure/azure-powershell/issues/5692")]
-        [Trait(Category.AcceptanceType, Category.Flaky)]
+        [Fact]
+        [Trait(Category.AcceptanceType, Category.CheckIn)]
         public void TestWithValidVhdDiskFile()
         {
             ComputeTestController.NewInstance.RunPsTest("Test-NewAzureRmVhdVMWithValidDiskFile");

src/ResourceManager/Compute/Commands.Compute/Strategies/ComputeRp/ComputeStrategy.cs

@@ -45,7 +45,7 @@ public static string GetConnectionString(
             var url = fqdn + (port == null ? string.Empty : ":" + port);
             return imageAndOsType.OsType == OperatingSystemTypes.Windows
                 ? "mstsc /v:" + url
-                : "ssh " + user + "@" + url;
+                : "ssh " + (user == null ? string.Empty : user + "@") + url;
         }
     }
 }

src/ResourceManager/Compute/Commands.Compute/VirtualMachine/Operation/NewAzureVMCommand.cs

@@ -407,7 +407,7 @@ async Task StrategyExecuteCmdletAsync(IAsyncCmdlet asyncCmdlet)
                 psResult.FullyQualifiedDomainName = fqdn;
                 var connectionString = imageAndOsType.GetConnectionString(
                     fqdn,
-                    Credential.UserName);
+                    Credential?.UserName);
                 asyncCmdlet.WriteVerbose(
                     Resources.VirtualMachineUseConnectionString,
                     connectionString);