1 files changed, 152 insertions, 0 deletions
diff --git a/plugin/minimal/minimal_test.go b/plugin/minimal/minimal_test.go
new file mode 100644
index 000000000..b579a9970
--- /dev/null
+++ b/plugin/minimal/minimal_test.go
@@ -0,0 +1,152 @@
+package minimal
+
+import (
+	"context"
+	"testing"
+
+	"github.com/coredns/coredns/plugin"
+	"github.com/coredns/coredns/plugin/pkg/dnstest"
+	"github.com/coredns/coredns/plugin/test"
+	"github.com/miekg/dns"
+)
+
+// testHandler implements plugin.Handler and will be used to create a stub handler for the test
+type testHandler struct {
+	Response *test.Case
+	Next     plugin.Handler
+}
+
+func (t *testHandler) Name() string { return "test-handler" }
+
+func (t *testHandler) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	d := new(dns.Msg)
+	d.SetReply(r)
+	if t.Response != nil {
+		d.Answer = t.Response.Answer
+		d.Ns = t.Response.Ns
+		d.Extra = t.Response.Extra
+		d.Rcode = t.Response.Rcode
+	}
+	w.WriteMsg(d)
+	return 0, nil
+}
+
+func TestMinimizeResponse(t *testing.T) {
+	baseAnswer := []dns.RR{
+		test.A("example.com.  293 IN A 142.250.76.46"),
+	}
+	baseNs := []dns.RR{
+		test.NS("example.com.  157127 IN NS ns2.example.com."),
+		test.NS("example.com.  157127 IN NS ns1.example.com."),
+		test.NS("example.com.  157127 IN NS ns3.example.com."),
+		test.NS("example.com.  157127 IN NS ns4.example.com."),
+	}
+
+	baseExtra := []dns.RR{
+		test.A("ns2.example.com. 316273 IN A 216.239.34.10"),
+		test.AAAA("ns2.example.com. 157127 IN AAAA 2001:4860:4802:34::a"),
+		test.A("ns3.example.com. 316274 IN A 216.239.36.10"),
+		test.AAAA("ns3.example.com. 157127 IN AAAA 2001:4860:4802:36::a"),
+		test.A("ns1.example.com. 165555 IN A 216.239.32.10"),
+		test.AAAA("ns1.example.com. 165555 IN AAAA 2001:4860:4802:32::a"),
+		test.A("ns4.example.com. 190188 IN A 216.239.38.10"),
+		test.AAAA("ns4.example.com. 157127 IN AAAA 2001:4860:4802:38::a"),
+	}
+
+	tests := []struct {
+		active   bool
+		original test.Case
+		minimal  test.Case
+	}{
+		{ // minimization possible NoError case
+			original: test.Case{
+				Answer: baseAnswer,
+				Ns:     nil,
+				Extra:  baseExtra,
+				Rcode:  0,
+			},
+			minimal: test.Case{
+				Answer: baseAnswer,
+				Ns:     nil,
+				Extra:  nil,
+				Rcode:  0,
+			},
+		},
+		{ // delegate response case
+			original: test.Case{
+				Answer: nil,
+				Ns:     baseNs,
+				Extra:  baseExtra,
+				Rcode:  0,
+			},
+			minimal: test.Case{
+				Answer: nil,
+				Ns:     baseNs,
+				Extra:  baseExtra,
+				Rcode:  0,
+			},
+		}, { // negative response case
+			original: test.Case{
+				Answer: baseAnswer,
+				Ns:     baseNs,
+				Extra:  baseExtra,
+				Rcode:  2,
+			},
+			minimal: test.Case{
+				Answer: baseAnswer,
+				Ns:     baseNs,
+				Extra:  baseExtra,
+				Rcode:  2,
+			},
+		},
+	}
+
+	for i, tc := range tests {
+		req := new(dns.Msg)
+		req.SetQuestion("example.com", dns.TypeA)
+
+		tHandler := &testHandler{
+			Response: &tc.original,
+			Next:     nil,
+		}
+		o := &minimalHandler{Next: tHandler}
+		rec := dnstest.NewRecorder(&test.ResponseWriter{})
+		_, err := o.ServeDNS(context.TODO(), rec, req)
+
+		if err != nil {
+			t.Errorf("Expected no error, but got %q", err)
+		}
+
+		if len(tc.minimal.Answer) != len(rec.Msg.Answer) {
+			t.Errorf("Test %d: Expected %d Answer, but got %d", i, len(tc.minimal.Answer), len(req.Answer))
+			continue
+		}
+		if len(tc.minimal.Ns) != len(rec.Msg.Ns) {
+			t.Errorf("Test %d: Expected %d Ns, but got %d", i, len(tc.minimal.Ns), len(req.Ns))
+			continue
+		}
+
+		if len(tc.minimal.Extra) != len(rec.Msg.Extra) {
+			t.Errorf("Test %d: Expected %d Extras, but got %d", i, len(tc.minimal.Extra), len(req.Extra))
+			continue
+		}
+
+		for j, a := range rec.Msg.Answer {
+			if tc.minimal.Answer[j].String() != a.String() {
+				t.Errorf("Test %d: Expected Answer %d to be %v, but got %v", i, j, tc.minimal.Answer[j], a)
+			}
+		}
+
+		for j, a := range rec.Msg.Ns {
+			if tc.minimal.Ns[j].String() != a.String() {
+				t.Errorf("Test %d: Expected NS %d to be %v, but got %v", i, j, tc.minimal.Ns[j], a)
+			}
+		}
+
+		for j, a := range rec.Msg.Extra {
+			if tc.minimal.Extra[j].String() != a.String() {
+				t.Errorf("Test %d: Expected Extra %d to be %v, but got %v", i, j, tc.minimal.Extra[j], a)
+			}
+		}
+	}
+}