Merge pull request #36512 from hashicorp/b-aws_route-duplicate-route-…

…propagation

r/aws_route: Don't fail on Create if there's already a propagated (or local) route to the same destination

.changelog/36512.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_route: Allow resource creation if a propagated route to the same destination exists
+```

internal/service/ec2/vpc_route.go

@@ -239,13 +239,14 @@ func resourceRouteCreate(ctx context.Context, d *schema.ResourceData, meta inter
 		return sdkdiag.AppendErrorf(diags, "creating Route: unexpected route target attribute: %q", targetAttributeKey)
 	}
 
-	_, err = routeFinder(ctx, conn, routeTableID, destination)
+	route, err := routeFinder(ctx, conn, routeTableID, destination)
 
 	switch {
 	case err == nil:
-		return sdkdiag.AppendFromErr(diags, routeAlreadyExistsError(routeTableID, destination))
+		if aws.StringValue(route.Origin) == ec2.RouteOriginCreateRoute {
+			return sdkdiag.AppendFromErr(diags, routeAlreadyExistsError(routeTableID, destination))
+		}
 	case tfresource.NotFound(err):
-		break
 	default:
 		return sdkdiag.AppendErrorf(diags, "reading Route: %s", err)
 	}

internal/service/ec2/vpc_route_test.go

@@ -1573,8 +1573,38 @@ func TestAccVPCRoute_ipv6ToVPCEndpoint(t *testing.T) {
 	})
 }
 
+func TestAccVPCRoute_localRouteCreateError(t *testing.T) {
+	ctx := acctest.Context(t)
+	var routeTable ec2.RouteTable
+	var vpc ec2.Vpc
+	rtResourceName := "aws_route_table.test"
+	vpcResourceName := "aws_vpc.test"
+	rName := sdkacctest.RandomWithPrefix(acctest.ResourcePrefix)
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck:                 func() { acctest.PreCheck(ctx, t) },
+		ErrorCheck:               acctest.ErrorCheck(t, names.EC2ServiceID),
+		ProtoV5ProviderFactories: acctest.ProtoV5ProviderFactories,
+		CheckDestroy:             testAccCheckRouteDestroy(ctx),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccVPCRouteConfig_ipv4NoRoute(rName),
+				Check: resource.ComposeTestCheckFunc(
+					acctest.CheckVPCExists(ctx, vpcResourceName, &vpc),
+					testAccCheckRouteTableExists(ctx, rtResourceName, &routeTable),
+					testAccCheckRouteTableNumberOfRoutes(&routeTable, 1),
+				),
+			},
+			{
+				Config:      testAccVPCRouteConfig_ipv4Local(rName),
+				ExpectError: regexache.MustCompile("cannot create local Route, use `terraform import` to manage existing local Routes"),
+			},
+		},
+	})
+}
+
 // https://github.com/hashicorp/terraform-provider-aws/issues/11455.
-func TestAccVPCRoute_localRoute(t *testing.T) {
+func TestAccVPCRoute_localRouteImport(t *testing.T) {
 	ctx := acctest.Context(t)
 	var routeTable ec2.RouteTable
 	var vpc ec2.Vpc
@@ -1615,7 +1645,7 @@ func TestAccVPCRoute_localRoute(t *testing.T) {
 }
 
 // https://github.com/hashicorp/terraform-provider-aws/issues/21350.
-func TestAccVPCRoute_localRouteUpdate(t *testing.T) {
+func TestAccVPCRoute_localRouteImportAndUpdate(t *testing.T) {
 	ctx := acctest.Context(t)
 	var routeTable ec2.RouteTable
 	var vpc ec2.Vpc