test default prefix/indent values + encoder errors

internal/cnf/parser/nginx/encoder_test.go

@@ -89,6 +89,83 @@ func TestDecodeEncode(t *testing.T) {
 	}
 }
 
+func TestErrors(t *testing.T) {
+	tests := []struct {
+		Receiver interface{}
+		Input    string
+		Err      error
+	}{
+		{new(Line), "", nil},
+		{nil, "", ErrInvalidReceiver},
+		{[]byte{}, "", ErrInvalidReceiver},
+	}
+
+	for i, test := range tests {
+
+		// create reader/writer
+		r, w := strings.NewReader(test.Input), &bytes.Buffer{}
+
+		// parse input
+		var receiver interface{} = new(Line)
+		decoder := NewDecoder(r)
+		if err := decoder.Decode(receiver); err != nil {
+			t.Errorf("[%d] unexpected error <%s>", i, err)
+			continue
+		}
+
+		// encode back to writer
+		receiver = test.Receiver
+		encoder := NewEncoder(w)
+		encoder.SetIndent("", "\t")
+		if err := encoder.Encode(receiver); err != test.Err {
+			t.Errorf("[%d] expected error <%s>, got <%s>", i, test.Err, err)
+			continue
+		}
+
+	}
+}
+
+func TestDefaultIndent(t *testing.T) {
+	tests := []struct {
+		Input     string
+		SetIndent []string
+		Output    string
+	}{
+		{"section {\nkey value;\n}\n", []string{"*prefix*", "*indent*"}, "*prefix*section {\n*prefix**indent*key\t\tvalue;\n*prefix*}\n\n"},
+		{"section {\nkey value;\n}\n", nil, "section {\n\tkey\t\tvalue;\n}\n\n"},
+	}
+
+	for i, test := range tests {
+
+		// create reader/writer
+		r, w := strings.NewReader(test.Input), &bytes.Buffer{}
+
+		// parse input
+		receiver := new(Line)
+		decoder := NewDecoder(r)
+		if err := decoder.Decode(receiver); err != nil {
+			t.Errorf("[%d] unexpected error <%s>", i, err)
+			continue
+		}
+
+		// encode back to writer
+		encoder := NewEncoder(w)
+		if test.SetIndent != nil && len(test.SetIndent) >= 2 {
+			encoder.SetIndent(test.SetIndent[0], test.SetIndent[1])
+		}
+		if err := encoder.Encode(receiver); err != nil {
+			t.Errorf("[%d] unexpected error <%s>", i, err)
+			continue
+		}
+
+		// check equality
+		if w.String() != test.Output {
+			t.Errorf("[%d] expected '%s', got '%s'", i, escape(test.Output), escape(w.String()))
+		}
+
+	}
+}
+
 func escape(raw string) string {
 
 	escaped := make([]rune, 0)