provider/aws: reading multiple pages of aws_efs_file_system tags (#12328)

Fixes: #12232

```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSEFSFileSystem_pagedTags'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSEFSFileSystem_pagedTags -timeout 120m
=== RUN   TestAccAWSEFSFileSystem_pagedTags
--- PASS: TestAccAWSEFSFileSystem_pagedTags (39.51s)
PASS
ok      github.com/hashicorp/terraform/builtin/providers/aws    39.537s
```

builtin/providers/aws/resource_aws_efs_file_system.go

@@ -149,15 +149,34 @@ func resourceAwsEfsFileSystemRead(d *schema.ResourceData, meta interface{}) erro
 		return fmt.Errorf("EFS file system %q could not be found.", d.Id())
 	}
 
-	tagsResp, err := conn.DescribeTags(&efs.DescribeTagsInput{
-		FileSystemId: aws.String(d.Id()),
-	})
-	if err != nil {
-		return fmt.Errorf("Error retrieving EC2 tags for EFS file system (%q): %s",
-			d.Id(), err.Error())
+	tags := make([]*efs.Tag, 0)
+	var marker string
+	for {
+		params := &efs.DescribeTagsInput{
+			FileSystemId: aws.String(d.Id()),
+		}
+		if marker != "" {
+			params.Marker = aws.String(marker)
+		}
+
+		tagsResp, err := conn.DescribeTags(params)
+		if err != nil {
+			return fmt.Errorf("Error retrieving EC2 tags for EFS file system (%q): %s",
+				d.Id(), err.Error())
+		}
+
+		for _, tag := range tagsResp.Tags {
+			tags = append(tags, tag)
+		}
+
+		if tagsResp.NextMarker != nil {
+			marker = *tagsResp.NextMarker
+		} else {
+			break
+		}
 	}
 
-	err = d.Set("tags", tagsToMapEFS(tagsResp.Tags))
+	err = d.Set("tags", tagsToMapEFS(tags))
 	if err != nil {
 		return err
 	}

builtin/providers/aws/resource_aws_efs_file_system_test.go

@@ -87,7 +87,7 @@ func TestAccAWSEFSFileSystem_basic(t *testing.T) {
 		Providers:    testAccProviders,
 		CheckDestroy: testAccCheckEfsFileSystemDestroy,
 		Steps: []resource.TestStep{
-			resource.TestStep{
+			{
 				Config: testAccAWSEFSFileSystemConfig,
 				Check: resource.ComposeTestCheckFunc(
 					resource.TestCheckResourceAttr(
@@ -103,7 +103,7 @@ func TestAccAWSEFSFileSystem_basic(t *testing.T) {
 					),
 				),
 			},
-			resource.TestStep{
+			{
 				Config: testAccAWSEFSFileSystemConfigWithTags,
 				Check: resource.ComposeTestCheckFunc(
 					testAccCheckEfsFileSystem(
@@ -122,7 +122,7 @@ func TestAccAWSEFSFileSystem_basic(t *testing.T) {
 					),
 				),
 			},
-			resource.TestStep{
+			{
 				Config: testAccAWSEFSFileSystemConfigWithPerformanceMode,
 				Check: resource.ComposeTestCheckFunc(
 					testAccCheckEfsFileSystem(
@@ -142,6 +142,32 @@ func TestAccAWSEFSFileSystem_basic(t *testing.T) {
 	})
 }
 
+func TestAccAWSEFSFileSystem_pagedTags(t *testing.T) {
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckEfsFileSystemDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccAWSEFSFileSystemConfigPagedTags,
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttr(
+						"aws_efs_file_system.foo",
+						"tags.%",
+						"11"),
+					//testAccCheckEfsFileSystem(
+					//	"aws_efs_file_system.foo",
+					//),
+					//testAccCheckEfsFileSystemPerformanceMode(
+					//	"aws_efs_file_system.foo",
+					//	"generalPurpose",
+					//),
+				),
+			},
+		},
+	})
+}
+
 func testAccCheckEfsFileSystemDestroy(s *terraform.State) error {
 	conn := testAccProvider.Meta().(*AWSClient).efsconn
 	for _, rs := range s.RootModule().Resources {
@@ -286,6 +312,25 @@ resource "aws_efs_file_system" "foo" {
 }
 `
 
+const testAccAWSEFSFileSystemConfigPagedTags = `
+resource "aws_efs_file_system" "foo" {
+	creation_token = "radeksimko"
+	tags {
+		Name = "foo-efs"
+		Another = "tag"
+		Test = "yes"
+		User = "root"
+		Page = "1"
+		Environment = "prod"
+		CostCenter = "terraform"
+		AcceptanceTest = "PagedTags"
+		CreationToken = "radek"
+		PerfMode = "max"
+		Region = "us-west-2"
+	}
+}
+`
+
 const testAccAWSEFSFileSystemConfigWithTags = `
 resource "aws_efs_file_system" "foo-with-tags" {
 	creation_token = "yada_yada"