From 3d198295f28906ab22622a68e218fd41c0050bc3 Mon Sep 17 00:00:00 2001
From: Paul Stack <public@paulstack.co.uk>
Date: Wed, 1 Mar 2017 15:30:39 +0000
Subject: [PATCH] provider/aws: No longer ForceNew resource on lambda_function
 runtime (#12329)

update

Fixes: #12181

```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSLambdaFunction_updateRuntime'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/01 11:20:18 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSLambdaFunction_updateRuntime -timeout 120m
=== RUN   TestAccAWSLambdaFunction_updateRuntime
--- PASS: TestAccAWSLambdaFunction_updateRuntime (110.25s)
PASS
ok  	github.com/hashicorp/terraform/builtin/providers/aws	110.279s
```
---
 .../aws/resource_aws_lambda_function.go       |  5 ++-
 .../aws/resource_aws_lambda_function_test.go  | 41 +++++++++++++++++++
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/builtin/providers/aws/resource_aws_lambda_function.go b/builtin/providers/aws/resource_aws_lambda_function.go
index 2e0001d07..55db957a7 100644
--- a/builtin/providers/aws/resource_aws_lambda_function.go
+++ b/builtin/providers/aws/resource_aws_lambda_function.go
@@ -95,7 +95,6 @@ func resourceAwsLambdaFunction() *schema.Resource {
 			"runtime": {
 				Type:         schema.TypeString,
 				Required:     true,
-				ForceNew:     true,
 				ValidateFunc: validateRuntime,
 			},
 			"timeout": {
@@ -531,6 +530,10 @@ func resourceAwsLambdaFunctionUpdate(d *schema.ResourceData, meta interface{}) e
 			configUpdate = true
 		}
 	}
+	if d.HasChange("runtime") {
+		configReq.Runtime = aws.String(d.Get("runtime").(string))
+		configUpdate = true
+	}
 	if d.HasChange("environment") {
 		if v, ok := d.GetOk("environment"); ok {
 			environments := v.([]interface{})
diff --git a/builtin/providers/aws/resource_aws_lambda_function_test.go b/builtin/providers/aws/resource_aws_lambda_function_test.go
index 5575adcca..739b62e2f 100644
--- a/builtin/providers/aws/resource_aws_lambda_function_test.go
+++ b/builtin/providers/aws/resource_aws_lambda_function_test.go
@@ -40,6 +40,35 @@ func TestAccAWSLambdaFunction_basic(t *testing.T) {
 	})
 }
 
+func TestAccAWSLambdaFunction_updateRuntime(t *testing.T) {
+	var conf lambda.GetFunctionOutput
+
+	rSt := acctest.RandString(5)
+	rName := fmt.Sprintf("tf_test_%s", rSt)
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckLambdaFunctionDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccAWSLambdaConfigBasic(rName, rSt),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckAwsLambdaFunctionExists("aws_lambda_function.lambda_function_test", rName, &conf),
+					resource.TestCheckResourceAttr("aws_lambda_function.lambda_function_test", "runtime", "nodejs4.3"),
+				),
+			},
+			{
+				Config: testAccAWSLambdaConfigBasicUpdateRuntime(rName, rSt),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckAwsLambdaFunctionExists("aws_lambda_function.lambda_function_test", rName, &conf),
+					resource.TestCheckResourceAttr("aws_lambda_function.lambda_function_test", "runtime", "nodejs4.3-edge"),
+				),
+			},
+		},
+	})
+}
+
 func TestAccAWSLambdaFunction_expectFilenameAndS3Attributes(t *testing.T) {
 	rSt := acctest.RandString(5)
 	rName := fmt.Sprintf("tf_test_%s", rSt)
@@ -792,6 +821,18 @@ resource "aws_lambda_function" "lambda_function_test" {
 `, rName)
 }
 
+func testAccAWSLambdaConfigBasicUpdateRuntime(rName, rSt string) string {
+	return fmt.Sprintf(baseAccAWSLambdaConfig(rSt)+`
+resource "aws_lambda_function" "lambda_function_test" {
+    filename = "test-fixtures/lambdatest.zip"
+    function_name = "%s"
+    role = "${aws_iam_role.iam_for_lambda.arn}"
+    handler = "exports.example"
+    runtime = "nodejs4.3-edge"
+}
+`, rName)
+}
+
 func testAccAWSLambdaConfigWithoutFilenameAndS3Attributes(rName, rSt string) string {
 	return fmt.Sprintf(baseAccAWSLambdaConfig(rSt)+`
 resource "aws_lambda_function" "lambda_function_test" {