Resolved dns_record_set clearing rrdatas (#4725) (#3207)

* Updated func

* fixed misc

Signed-off-by: Modular Magician <magic-modules@google.com>

.changelog/4725.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+dns: fixed empty `rrdatas` list on `google_dns_record_set` for AAAA records
+```

google-beta/resource_dataflow_flex_template_job_test.go

@@ -8,7 +8,7 @@ import (
 
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/resource"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/terraform"
-	compute "google.golang.org/api/compute/v1"
+	"google.golang.org/api/compute/v1"
 )
 
 func TestAccDataflowFlexTemplateJob_basic(t *testing.T) {

google-beta/resource_dns_record_set_test.go

@@ -2,6 +2,7 @@ package google
 
 import (
 	"fmt"
+	"net"
 	"strings"
 	"testing"
 
@@ -11,23 +12,42 @@ import (
 
 func TestIpv6AddressDiffSuppress(t *testing.T) {
 	cases := map[string]struct {
-		Old, New       string
+		Old, New       []string
 		ShouldSuppress bool
 	}{
 		"compact form should suppress diff": {
-			Old:            "2a03:b0c0:1:e0::29b:8001",
-			New:            "2a03:b0c0:0001:00e0:0000:0000:029b:8001",
+			Old:            []string{"2a03:b0c0:1:e0::29b:8001"},
+			New:            []string{"2a03:b0c0:0001:00e0:0000:0000:029b:8001"},
 			ShouldSuppress: true,
 		},
 		"different address should not suppress diff": {
-			Old:            "2a03:b0c0:1:e00::29b:8001",
-			New:            "2a03:b0c0:0001:00e0:0000:0000:029b:8001",
+			Old:            []string{"2a03:b0c0:1:e00::29b:8001"},
+			New:            []string{"2a03:b0c0:0001:00e0:0000:0000:029b:8001"},
 			ShouldSuppress: false,
 		},
+		"increase address should not suppress diff": {
+			Old:            []string{""},
+			New:            []string{"2a03:b0c0:0001:00e0:0000:0000:029b:8001"},
+			ShouldSuppress: false,
+		},
+		"decrease address should not suppress diff": {
+			Old:            []string{"2a03:b0c0:1:e00::29b:8001"},
+			New:            []string{""},
+			ShouldSuppress: false,
+		},
+		"switch address positions should suppress diff": {
+			Old:            []string{"2a03:b0c0:1:e00::28b:8001", "2a03:b0c0:1:e0::29b:8001"},
+			New:            []string{"2a03:b0c0:1:e0::29b:8001", "2a03:b0c0:1:e00::28b:8001"},
+			ShouldSuppress: true,
+		},
+	}
+
+	parseFunc := func(x string) string {
+		return net.ParseIP(x).String()
 	}
 
 	for tn, tc := range cases {
-		shouldSuppress := ipv6AddressforDnsDiffSuppress("", tc.Old, tc.New, nil)
+		shouldSuppress := rrdatasListDiffSuppress(tc.Old, tc.New, parseFunc, nil)
 		if shouldSuppress != tc.ShouldSuppress {
 			t.Errorf("%s: expected %t", tn, tc.ShouldSuppress)
 		}

google-beta/resource_dns_resource_dns_record_set.go

@@ -28,23 +28,55 @@ import (
 )
 
 func rrdatasDnsDiffSuppress(k, old, new string, d *schema.ResourceData) bool {
-	if d.Get("type") == "AAAA" {
-		return ipv6AddressforDnsDiffSuppress(k, old, new, d)
-	}
-	if d.Get("type") == "MX" {
-		return (strings.ToLower(old) == strings.ToLower(new))
-	}
-	if d.Get("type") == "TXT" {
-		return strings.ToLower(strings.Trim(old, `"`)) == strings.ToLower(strings.Trim(new, `"`))
+	o, n := d.GetChange("rrdatas")
+	if o == nil || n == nil {
+		return false
+	}
+
+	oList := convertStringArr(o.([]interface{}))
+	nList := convertStringArr(n.([]interface{}))
+
+	parseFunc := func(record string) string {
+		switch d.Get("type") {
+		case "AAAA":
+			// parse ipv6 to a key from one list
+			return net.ParseIP(record).String()
+		case "MX":
+			return strings.ToLower(record)
+		case "TXT":
+			return strings.ToLower(strings.Trim(record, `"`))
+		default:
+			return record
+		}
 	}
-	return false
+	return rrdatasListDiffSuppress(oList, nList, parseFunc, d)
 }
 
-func ipv6AddressforDnsDiffSuppress(_, old, new string, _ *schema.ResourceData) bool {
-	oldIp := net.ParseIP(old)
-	newIp := net.ParseIP(new)
-
-	return oldIp.Equal(newIp)
+// suppress on a list when 1) its items have dups that need to be ignored
+// and 2) string comparison on the items may need a special parse function
+// example of usage can be found ../../../third_party/terraform/tests/resource_dns_record_set_test.go.erb
+func rrdatasListDiffSuppress(oldList, newList []string, fun func(x string) string, _ *schema.ResourceData) bool {
+	// compare two lists of unordered records
+	diff := make(map[string]bool, len(oldList))
+	for _, oldRecord := range oldList {
+		// set all new IPs to true
+		diff[fun(oldRecord)] = true
+	}
+	for _, newRecord := range newList {
+		// set matched IPs to false otherwise can't suppress
+		if diff[fun(newRecord)] {
+			diff[fun(newRecord)] = false
+		} else {
+			return false
+		}
+	}
+	// can't suppress if unmatched records are found
+	for _, element := range diff {
+		if element {
+			return false
+		}
+	}
+	return true
 }
 
 func resourceDNSResourceDnsRecordSet() *schema.Resource {