testutils: improve validate DefaultDRPCOption error message

This improves the error message when node level server args are used
instead of top-level server args for a test cluster.

before: "improper use of DefaultDRPCOption in per-server args: 1 vs 0"
now   : "improper use of DefaultDRPCOption in per-server args: enabled vs unset"

Release note: none
Epic: none

Author: shubhamdhama

pkg/base/test_server_args.go

@@ -251,6 +251,21 @@ const (
 	TestDRPCEnabledRandomly
 )
 
+func (d DefaultTestDRPCOption) String() string {
+	switch d {
+	case TestDRPCUnset:
+		return "unset"
+	case TestDRPCDisabled:
+		return "disabled"
+	case TestDRPCEnabled:
+		return "enabled"
+	case TestDRPCEnabledRandomly:
+		return "enabled-randomly"
+	default:
+		panic("unreachable")
+	}
+}
+
 // TestClusterArgs contains the parameters one can set when creating a test
 // cluster. It contains a TestServerArgs instance which will be copied over to
 // every server.

pkg/testutils/testcluster/testcluster.go

@@ -281,16 +281,16 @@ func (tc *TestCluster) validateDefaultTestTenant(
 // validateDefaultDRPCOption checks that per-server args don't override
 // the top-level DefaultDRPCOption setting inconsistently.
 func (tc *TestCluster) validateDefaultDRPCOption(
-	t serverutils.TestFataler, nodes int, defaultDRPCOption base.DefaultTestDRPCOption,
+	t serverutils.TestFataler, nodes int, clusterDRPCOption base.DefaultTestDRPCOption,
 ) {
 	for i := range nodes {
 		if args, ok := tc.clusterArgs.ServerArgsPerNode[i]; ok &&
 			args.DefaultDRPCOption != base.TestDRPCUnset &&
-			args.DefaultDRPCOption != defaultDRPCOption {
+			args.DefaultDRPCOption != clusterDRPCOption {
 			tc.Stopper().Stop(context.Background())
 			t.Fatalf("improper use of DefaultDRPCOption in per-server args: %v vs %v\n"+
-				"Tip: use the top-level ServerArgs to set the default DRPC option.",
-				args.DefaultDRPCOption, defaultDRPCOption)
+				"Use the top-level ServerArgs to set the default DRPC option.",
+				args.DefaultDRPCOption, clusterDRPCOption)
 		}
 	}
 }