Adding support for an empty windows config block. Fixes #10744

builtin/providers/azurerm/resource_arm_virtual_machine.go

@@ -865,13 +865,16 @@ func resourceArmVirtualMachineStorageOsProfileLinuxConfigHash(v interface{}) int
 
 func resourceArmVirtualMachineStorageOsProfileWindowsConfigHash(v interface{}) int {
 	var buf bytes.Buffer
-	m := v.(map[string]interface{})
-	if m["provision_vm_agent"] != nil {
-		buf.WriteString(fmt.Sprintf("%t-", m["provision_vm_agent"].(bool)))
-	}
-	if m["enable_automatic_upgrades"] != nil {
-		buf.WriteString(fmt.Sprintf("%t-", m["enable_automatic_upgrades"].(bool)))
+
+	if m, ok := v.(map[string]interface{}); ok {
+		if m["provision_vm_agent"] != nil {
+			buf.WriteString(fmt.Sprintf("%t-", m["provision_vm_agent"].(bool)))
+		}
+		if m["enable_automatic_upgrades"] != nil {
+			buf.WriteString(fmt.Sprintf("%t-", m["enable_automatic_upgrades"].(bool)))
+		}
 	}
+
 	return hashcode.String(buf.String())
 }
 

builtin/providers/azurerm/resource_arm_virtual_machine_test.go

@@ -261,6 +261,25 @@ func TestAccAzureRMVirtualMachine_basicWindowsMachine(t *testing.T) {
 	})
 }
 
+func TestAccAzureRMVirtualMachine_basicWindowsMachineEmptyConfigBlock(t *testing.T) {
+	var vm compute.VirtualMachine
+	ri := acctest.RandInt()
+	config := fmt.Sprintf(testAccAzureRMVirtualMachine_basicWindowsMachineEmptyConfigBlock, ri, ri, ri, ri, ri, ri)
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testCheckAzureRMVirtualMachineDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: config,
+				Check: resource.ComposeTestCheckFunc(
+					testCheckAzureRMVirtualMachineExists("azurerm_virtual_machine.test", &vm),
+				),
+			},
+		},
+	})
+}
+
 func TestAccAzureRMVirtualMachine_windowsUnattendedConfig(t *testing.T) {
 	var vm compute.VirtualMachine
 	ri := acctest.RandInt()
@@ -2147,6 +2166,87 @@ resource "azurerm_virtual_machine" "test" {
 }
 `
 
+var testAccAzureRMVirtualMachine_basicWindowsMachineEmptyConfigBlock = `
+resource "azurerm_resource_group" "test" {
+    name = "acctestRG-%d"
+    location = "West US 2"
+}
+
+resource "azurerm_virtual_network" "test" {
+    name = "acctvn-%d"
+    address_space = ["10.0.0.0/16"]
+    location = "West US 2"
+    resource_group_name = "${azurerm_resource_group.test.name}"
+}
+
+resource "azurerm_subnet" "test" {
+    name = "acctsub-%d"
+    resource_group_name = "${azurerm_resource_group.test.name}"
+    virtual_network_name = "${azurerm_virtual_network.test.name}"
+    address_prefix = "10.0.2.0/24"
+}
+
+resource "azurerm_network_interface" "test" {
+    name = "acctni-%d"
+    location = "West US 2"
+    resource_group_name = "${azurerm_resource_group.test.name}"
+
+    ip_configuration {
+    	name = "testconfiguration1"
+    	subnet_id = "${azurerm_subnet.test.id}"
+    	private_ip_address_allocation = "dynamic"
+    }
+}
+
+resource "azurerm_storage_account" "test" {
+    name = "accsa%d"
+    resource_group_name = "${azurerm_resource_group.test.name}"
+    location = "West US 2"
+    account_type = "Standard_LRS"
+
+    tags {
+        environment = "staging"
+    }
+}
+
+resource "azurerm_storage_container" "test" {
+    name = "vhds"
+    resource_group_name = "${azurerm_resource_group.test.name}"
+    storage_account_name = "${azurerm_storage_account.test.name}"
+    container_access_type = "private"
+}
+
+resource "azurerm_virtual_machine" "test" {
+    name = "acctvm-%d"
+    location = "West US 2"
+    resource_group_name = "${azurerm_resource_group.test.name}"
+    network_interface_ids = ["${azurerm_network_interface.test.id}"]
+    vm_size = "Standard_D1_v2"
+
+    storage_image_reference {
+	publisher = "MicrosoftWindowsServer"
+	offer = "WindowsServer"
+	sku = "2012-Datacenter"
+	version = "latest"
+    }
+
+    storage_os_disk {
+        name = "myosdisk1"
+        vhd_uri = "${azurerm_storage_account.test.primary_blob_endpoint}${azurerm_storage_container.test.name}/myosdisk1.vhd"
+        caching = "ReadWrite"
+        create_option = "FromImage"
+    }
+
+    os_profile {
+	computer_name = "winhost01"
+	admin_username = "testadmin"
+	admin_password = "Password1234!"
+    }
+
+    os_profile_windows_config {}
+}
+`
+
 var testAccAzureRMVirtualMachine_windowsUnattendedConfig = `
 resource "azurerm_resource_group" "test" {
     name = "acctestRG-%d"