From 86c4678bee1de6f711cd13c49ea6b47abd699371 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Thu, 10 Jul 2014 14:51:23 -0700
Subject: [PATCH] providers/aws: test internet gateway changing the VPC addr

---
 .../aws/resource_aws_internet_gateway_test.go | 43 ++++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/builtin/providers/aws/resource_aws_internet_gateway_test.go b/builtin/providers/aws/resource_aws_internet_gateway_test.go
index 11f4aaea9..094a923ad 100644
--- a/builtin/providers/aws/resource_aws_internet_gateway_test.go
+++ b/builtin/providers/aws/resource_aws_internet_gateway_test.go
@@ -2,6 +2,7 @@ package aws
 
 import (
 	"fmt"
+	"log"
 	"testing"
 
 	"github.com/hashicorp/terraform/helper/resource"
@@ -10,7 +11,24 @@ import (
 )
 
 func TestAccAWSInternetGateway(t *testing.T) {
-	var v ec2.InternetGateway
+	var v, v2 ec2.InternetGateway
+
+	testNotEqual := func(*terraform.State) error {
+		if len(v.Attachments) == 0 {
+			return fmt.Errorf("IG A is not attached")
+		}
+		if len(v2.Attachments) == 0 {
+			return fmt.Errorf("IG B is not attached")
+		}
+
+		id1 := v.Attachments[0].VpcId
+		id2 := v2.Attachments[0].VpcId
+		if id1 == id2 {
+			return fmt.Errorf("Both attachment IDs are the same")
+		}
+
+		return nil
+	}
 
 	resource.Test(t, resource.TestCase{
 		PreCheck:     func() { testAccPreCheck(t) },
@@ -24,6 +42,15 @@ func TestAccAWSInternetGateway(t *testing.T) {
 						"aws_internet_gateway.foo", &v),
 				),
 			},
+
+			resource.TestStep{
+				Config: testAccInternetGatewayConfigChangeVPC,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckInternetGatewayExists(
+						"aws_internet_gateway.foo", &v2),
+					testNotEqual,
+				),
+			},
 		},
 	})
 }
@@ -96,3 +123,17 @@ resource "aws_internet_gateway" "foo" {
 	vpc_id = "${aws_vpc.foo.id}"
 }
 `
+
+const testAccInternetGatewayConfigChangeVPC = `
+resource "aws_vpc" "foo" {
+	cidr_block = "10.1.0.0/16"
+}
+
+resource "aws_vpc" "bar" {
+	cidr_block = "10.2.0.0/16"
+}
+
+resource "aws_internet_gateway" "foo" {
+	vpc_id = "${aws_vpc.bar.id}"
+}
+`