provider/aws: Fix panic in aws_acm_certificate datasource (#10051)

Fixes #10042
Fixes #9989

Another panic was found with this resource. IT essentially was causing a
panic when no certificates were found. This was due to the casting of
status to []string

There are times when there are no statuses passed in. Made the error
message a lot more generic now rather than having something like this

```

No certificate with statuses [] for domain mytestdomain.com found in this region.
```

This now becomes:

```
No certificate for domain mytestdomain.com found in this region.
```

Also, added a test to show that the panic is gone

```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAwsAcmCertificateDataSource_'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2016/11/11 15:11:33 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v
-run=TestAccAwsAcmCertificateDataSource_ -timeout 120m
=== RUN   TestAccAwsAcmCertificateDataSource_noMatchReturnsError
--- PASS: TestAccAwsAcmCertificateDataSource_noMatchReturnsError (6.07s)
PASS
ok      github.com/hashicorp/terraform/builtin/providers/aws6.094s
```

builtin/providers/aws/data_source_aws_acm_certificate.go

@@ -2,7 +2,6 @@ package aws
 
 import (
 	"fmt"
-	"strings"
 	"time"
 
 	"github.com/aws/aws-sdk-go/aws"
@@ -41,11 +40,7 @@ func dataSourceAwsAcmCertificateRead(d *schema.ResourceData, meta interface{}) e
 	statuses, ok := d.GetOk("statuses")
 	if ok {
 		statusStrings := statuses.([]interface{})
-		statusList := make([]*string, len(statusStrings))
-		for i, status := range statusStrings {
-			statusList[i] = aws.String(strings.ToUpper(status.(string)))
-		}
-		params.CertificateStatuses = statusList
+		params.CertificateStatuses = expandStringList(statusStrings)
 	} else {
 		params.CertificateStatuses = []*string{aws.String("ISSUED")}
 	}
@@ -65,12 +60,10 @@ func dataSourceAwsAcmCertificateRead(d *schema.ResourceData, meta interface{}) e
 	}
 
 	if len(arns) == 0 {
-		return fmt.Errorf("No certificate with statuses [%s] for domain %q found in this region.",
-			strings.Join(statuses.([]string), ", "), target)
+		return fmt.Errorf("No certificate for domain %q found in this region.", target)
 	}
 	if len(arns) > 1 {
-		return fmt.Errorf("Multiple certificates with statuses [%s] for domain %s found in this region.",
-			strings.Join(statuses.([]string), ","), target)
+		return fmt.Errorf("Multiple certificates for domain %q found in this region.", target)
 	}
 
 	d.SetId(time.Now().UTC().String())

builtin/providers/aws/data_source_aws_acm_certificate_test.go

@@ -2,62 +2,45 @@ package aws
 
 import (
 	"fmt"
-	"os"
+	"regexp"
 	"testing"
 
 	"github.com/hashicorp/terraform/helper/resource"
-	"github.com/hashicorp/terraform/terraform"
 )
 
-func TestAccAwsAcmCertificateDataSource_basic(t *testing.T) {
-	region := os.Getenv("AWS_ACM_TEST_REGION")
-	domain := os.Getenv("AWS_ACM_TEST_DOMAIN")
-	certArn := os.Getenv("AWS_ACM_TEST_CERT_ARN")
+func TestAccAwsAcmCertificateDataSource_noMatchReturnsError(t *testing.T) {
+	domain := "hashicorp.com"
 	resource.Test(t, resource.TestCase{
 		PreCheck: func() {
 			testAccPreCheck(t)
-			if region == "" {
-				t.Skip("AWS_ACM_TEST_REGION must be set to a region an ACM certificate pre-created for this test.")
-			}
-			if domain == "" {
-				t.Skip("AWS_ACM_TEST_DOMAIN must be set to a domain with an ACM certificate pre-created for this test.")
-			}
-			if certArn == "" {
-				t.Skip("AWS_ACM_TEST_CERT_ARN must be set to the ARN of an ACM cert pre-created for this test.")
-			}
 		},
 		Providers: testAccProviders,
 		Steps: []resource.TestStep{
 			{
-				Config: testAccCheckAwsAcmCertificateDataSourceConfig(region, domain),
-				Check:  testAccCheckAcmArnMatches("data.aws_acm_certificate.test", certArn),
+				Config:      testAccCheckAwsAcmCertificateDataSourceConfig(domain),
+				ExpectError: regexp.MustCompile(`No certificate for domain`),
+			},
+			{
+				Config:      testAccCheckAwsAcmCertificateDataSourceConfigWithStatus(domain),
+				ExpectError: regexp.MustCompile(`No certificate for domain`),
 			},
 		},
 	})
 }
 
-func testAccCheckAcmArnMatches(name, expectArn string) resource.TestCheckFunc {
-	return func(s *terraform.State) error {
-		ms := s.RootModule()
-		rs, ok := ms.Resources[name]
-		if !ok {
-			return fmt.Errorf("Not found: %s", name)
-		}
-		gotArn := rs.Primary.Attributes["arn"]
-		if gotArn != expectArn {
-			return fmt.Errorf("Expected cert to have arn: %s, got: %s", expectArn, gotArn)
-		}
-		return nil
-	}
+func testAccCheckAwsAcmCertificateDataSourceConfig(domain string) string {
+	return fmt.Sprintf(`
+data "aws_acm_certificate" "test" {
+	domain = "%s"
+}
+`, domain)
 }
 
-func testAccCheckAwsAcmCertificateDataSourceConfig(region, domain string) string {
+func testAccCheckAwsAcmCertificateDataSourceConfigWithStatus(domain string) string {
 	return fmt.Sprintf(`
-provider "aws" {
-	region = "%s"
-}
 data "aws_acm_certificate" "test" {
 	domain = "%s"
+	statuses = ["ISSUED"]
 }
-	`, region, domain)
+`, domain)
 }