Add a test for when only 1 side has ipv6 addresses

main.tf

@@ -94,10 +94,10 @@ resource "aws_route" "peer_routes" {
 resource "aws_route" "peer_ipv6_routes" {
   provider = aws.peer
   # Only create routes for peer route table if input dictates it, and in that case, for all combinations
-  count                     = local.create_routes_peer ? length(local.peer_ipv6_routes) : 0
-  route_table_id            = local.peer_ipv6_routes[count.index].rts_id
-  destination_cidr_block    = local.peer_ipv6_routes[count.index].dest_ipv6_cidr
-  vpc_peering_connection_id = aws_vpc_peering_connection.this.id
+  count                       = local.create_routes_peer ? length(local.peer_ipv6_routes) : 0
+  route_table_id              = local.peer_ipv6_routes[count.index].rts_id
+  destination_ipv6_cidr_block = local.peer_ipv6_routes[count.index].dest_ipv6_cidr
+  vpc_peering_connection_id   = aws_vpc_peering_connection.this.id
 }
 
 ###################

test/fixtures/single-account-single-region-one-dualstack/main.tf

@@ -0,0 +1,73 @@
+// Fixtures
+// VPC
+resource "aws_vpc" "this" {
+  cidr_block                       = "172.20.0.0/16"
+  assign_generated_ipv6_cidr_block = true
+
+  tags = {
+    Name        = "this_vpc"
+    Environment = "Test"
+  }
+}
+
+resource "aws_vpc" "peer" {
+  cidr_block                       = "172.21.0.0/16"
+  assign_generated_ipv6_cidr_block = false
+
+  tags = {
+    Name        = "peer_vpc"
+    Environment = "Test"
+  }
+}
+
+// Route Tables
+resource "aws_route_table" "this" {
+  count    = length(var.azs)
+
+  vpc_id = aws_vpc.this.id
+
+  tags = {
+    Name        = "This VPC RT"
+    Environment = "Test"
+  }
+}
+
+resource "aws_route_table" "peer" {
+  count    = length(var.azs)
+
+  vpc_id = aws_vpc.peer.id
+
+  tags = {
+    Name        = "Peer VPC RT"
+    Environment = "Test"
+  }
+}
+
+// Subnets
+resource "aws_subnet" "this" {
+  for_each = toset(var.azs)
+
+  vpc_id     = aws_vpc.this.id
+  cidr_block = cidrsubnet(aws_vpc.this.cidr_block, 5, index(var.azs, each.value))
+  // IPV6 Subnet cidr needs to align to /64, aws provides a /56 CIDR automatically
+  ipv6_cidr_block   = cidrsubnet(aws_vpc.this.ipv6_cidr_block, 8, index(var.azs, each.value))
+  availability_zone = each.value
+
+  tags = {
+    Name        = "This VPC Subnet"
+    Environment = "Test"
+  }
+}
+
+resource "aws_subnet" "peer" {
+  for_each = toset(var.azs)
+
+  vpc_id     = aws_vpc.peer.id
+  cidr_block = cidrsubnet(aws_vpc.peer.cidr_block, 5, index(var.azs, each.value))
+  availability_zone = each.value
+
+  tags = {
+    Name        = "This VPC Subnet"
+    Environment = "Test"
+  }
+}

test/fixtures/single-account-single-region-one-dualstack/outputs.tf

@@ -0,0 +1,7 @@
+output "this_vpc_id" {
+  value = aws_vpc.this.id
+}
+
+output "peer_vpc_id" {
+  value = aws_vpc.peer.id
+}

test/fixtures/single-account-single-region-one-dualstack/provider.tf

@@ -0,0 +1,13 @@
+provider "aws" {
+  endpoints {
+    ec2 = "http://localhost:4566"
+    s3  = "http://localhost:4566"
+    sts = "http://localhost:4566"
+  }
+  region                      = "eu-west-1"
+  access_key                  = "null"
+  secret_key                  = "null"
+  skip_credentials_validation = true
+  skip_metadata_api_check     = true
+  skip_requesting_account_id  = true
+}

test/fixtures/single-account-single-region-one-dualstack/variables.tf

@@ -0,0 +1,5 @@
+variable "azs" {
+  description = "Availability Zones"
+  type        = list(string)
+  default     = ["eu-west-1a", "eu-west-1b", "eu-west-1c"]
+}

test/peering-active_test.go

@@ -17,9 +17,10 @@ func TestPeeringActive(t *testing.T) {
 	testCases := []TestCase{
 		{"SingleAccountSingleRegion", "./fixtures/single-account-single-region", "../examples/single-account-single-region"},
 		{"SingleAccountSingleRegionWithOptions", "./fixtures/single-account-single-region-with-options", "../examples/single-account-single-region-with-options"},
+		{"SingleAccountSingleRegionOneDualstack", "./fixtures/single-account-single-region-one-dualstack", "../examples/single-account-single-region"},
 		{"SingleAccountMultiRegion", "./fixtures/single-account-multi-region", "../examples/single-account-multi-region"},
 		{"MultiAccountSingleRegion", "./fixtures/multi-account-single-region", "../examples/multi-account-single-region"},
-		{"MultiAccountSingleRegionDualstack", "./fixtures/multi-account-single-region-dualstack", "../examples/multi-account-single-region"},
+		{"MultiAccountSingleRegionBothDualstack", "./fixtures/multi-account-single-region-both-dualstack", "../examples/multi-account-single-region"},
 		{"MultiAccountMultiRegion", "./fixtures/multi-account-multi-region", "../examples/multi-account-multi-region"},
 		// There is a bug with `depends_on` functionality.
 		//{"ModuleDependsOn", "", "../examples/module-depends-on"},