add closest encloser stuff

middleware/file/closest_test.go

@@ -0,0 +1,34 @@
+package file
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/miekg/dns"
+)
+
+func TestClosestEncloser(t *testing.T) {
+	z, err := Parse(strings.NewReader(dbMiekNL), testzone, "stdin")
+	if err != nil {
+		t.Fatalf("expect no error when reading zone, got %q", err)
+	}
+
+	tests := []struct {
+		in, out string
+	}{
+		{"miek.nl.", "miek.nl."},
+		{"blaat.miek.nl.", "miek.nl."},
+		{"blaat.blaat.miek.nl.", "miek.nl."},
+		{"blaat.a.miek.nl.", "archive.miek.nl."},
+	}
+
+	mk, _ := dns.TypeToRR[dns.TypeA]
+	rr := mk()
+	for _, tc := range tests {
+		rr.Header().Name = tc.in
+		ce := z.ClosestEncloser(rr)
+		if ce != tc.out {
+			t.Errorf("expected ce to be %s for %s, got %s", tc.out, tc.in, ce)
+		}
+	}
+}