Add acceptance test for instance file data source

Signed-off-by: Thiago Padilha <[email protected]>

lxd/data_lxd_instance_file_test.go

@@ -0,0 +1,46 @@
+package lxd
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	petname "github.com/dustinkirkland/golang-petname"
+
+	"github.com/hashicorp/terraform-plugin-testing/helper/resource"
+)
+
+func TestAccInstanceFileDataSource(t *testing.T) {
+	content := "Welcome to Alpine Linux 3.16\nKernel \\r on an \\m (\\l)\n\n"
+
+	instanceName := strings.ToLower(petname.Generate(2, "-"))
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccDataInstanceFile(instanceName),
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttr("data.lxd_instance_file.file1", "content", content),
+				),
+			},
+		},
+	})
+}
+
+func testAccDataInstanceFile(name string) string {
+	return fmt.Sprintf(`
+resource "lxd_instance" "instance1" {
+  name = "%s"
+  image = "images:alpine/3.16/amd64"
+  profiles = ["default"]
+}
+
+data "lxd_instance_file" "file1" {
+	instance_name = "${lxd_instance.instance1.name}"
+	target_file = "/etc/issue"
+	timeout = 30
+}
+	`, name)
+}