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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package gob
import (
"bytes";
"gob";
"os";
"reflect";
"strings";
"testing";
"unsafe";
)
type ET2 struct {
x string;
}
type ET1 struct {
a int;
et2 *ET2;
next *ET1;
}
// Like ET1 but with a different name for a field
type ET3 struct {
a int;
et2 *ET2;
differentNext *ET1;
}
// Like ET1 but with a different type for a field
type ET4 struct {
a int;
et2 *ET1;
next int;
}
func TestBasicEncoder(t *testing.T) {
b := new(bytes.Buffer);
enc := NewEncoder(b);
et1 := new(ET1);
et1.a = 7;
et1.et2 = new(ET2);
enc.Encode(et1);
if enc.state.err != nil {
t.Error("encoder fail:", enc.state.err)
}
// Decode the result by hand to verify;
state := new(decodeState);
state.b = b;
// The output should be:
// 0) The length, 38.
length := decodeUint(state);
if length != 38 {
t.Fatal("0. expected length 38; got", length);
}
// 1) -7: the type id of ET1
id1 := decodeInt(state);
if id1 >= 0 {
t.Fatal("expected ET1 negative id; got", id1);
}
// 2) The wireType for ET1
wire1 := new(wireType);
err := decode(b, tWireType, wire1);
if err != nil {
t.Fatal("error decoding ET1 type:", err);
}
info := getTypeInfo(reflect.Typeof(ET1{}));
trueWire1 := &wireType{s: info.id.gobType().(*structType)};
if !reflect.DeepEqual(wire1, trueWire1) {
t.Fatalf("invalid wireType for ET1: expected %+v; got %+v\n", *trueWire1, *wire1);
}
// 3) The length, 21.
length = decodeUint(state);
if length != 21 {
t.Fatal("3. expected length 21; got", length);
}
// 4) -8: the type id of ET2
id2 := decodeInt(state);
if id2 >= 0 {
t.Fatal("expected ET2 negative id; got", id2);
}
// 5) The wireType for ET2
wire2 := new(wireType);
err = decode(b, tWireType, wire2);
if err != nil {
t.Fatal("error decoding ET2 type:", err);
}
info = getTypeInfo(reflect.Typeof(ET2{}));
trueWire2 := &wireType{s: info.id.gobType().(*structType)};
if !reflect.DeepEqual(wire2, trueWire2) {
t.Fatalf("invalid wireType for ET2: expected %+v; got %+v\n", *trueWire2, *wire2);
}
// 6) The length, 6.
length = decodeUint(state);
if length != 6 {
t.Fatal("6. expected length 6; got", length);
}
// 7) The type id for the et1 value
newId1 := decodeInt(state);
if newId1 != -id1 {
t.Fatal("expected Et1 id", -id1, "got", newId1);
}
// 8) The value of et1
newEt1 := new(ET1);
et1Id := getTypeInfo(reflect.Typeof(*newEt1)).id;
err = decode(b, et1Id, newEt1);
if err != nil {
t.Fatal("error decoding ET1 value:", err);
}
if !reflect.DeepEqual(et1, newEt1) {
t.Fatalf("invalid data for et1: expected %+v; got %+v\n", *et1, *newEt1);
}
// 9) EOF
if b.Len() != 0 {
t.Error("not at eof;", b.Len(), "bytes left")
}
// Now do it again. This time we should see only the type id and value.
b.Reset();
enc.Encode(et1);
if enc.state.err != nil {
t.Error("2nd round: encoder fail:", enc.state.err)
}
// The length.
length = decodeUint(state);
if length != 6 {
t.Fatal("6. expected length 6; got", length);
}
// 5a) The type id for the et1 value
newId1 = decodeInt(state);
if newId1 != -id1 {
t.Fatal("2nd round: expected Et1 id", -id1, "got", newId1);
}
// 6a) The value of et1
newEt1 = new(ET1);
err = decode(b, et1Id, newEt1);
if err != nil {
t.Fatal("2nd round: error decoding ET1 value:", err);
}
if !reflect.DeepEqual(et1, newEt1) {
t.Fatalf("2nd round: invalid data for et1: expected %+v; got %+v\n", *et1, *newEt1);
}
// 7a) EOF
if b.Len() != 0 {
t.Error("2nd round: not at eof;", b.Len(), "bytes left")
}
}
func TestEncoderDecoder(t *testing.T) {
b := new(bytes.Buffer);
enc := NewEncoder(b);
et1 := new(ET1);
et1.a = 7;
et1.et2 = new(ET2);
enc.Encode(et1);
if enc.state.err != nil {
t.Error("encoder fail:", enc.state.err)
}
dec := NewDecoder(b);
newEt1 := new(ET1);
dec.Decode(newEt1);
if dec.state.err != nil {
t.Fatal("error decoding ET1:", dec.state.err);
}
if !reflect.DeepEqual(et1, newEt1) {
t.Fatalf("invalid data for et1: expected %+v; got %+v\n", *et1, *newEt1);
}
if b.Len() != 0 {
t.Error("not at eof;", b.Len(), "bytes left")
}
enc.Encode(et1);
newEt1 = new(ET1);
dec.Decode(newEt1);
if dec.state.err != nil {
t.Fatal("round 2: error decoding ET1:", dec.state.err);
}
if !reflect.DeepEqual(et1, newEt1) {
t.Fatalf("round 2: invalid data for et1: expected %+v; got %+v\n", *et1, *newEt1);
}
if b.Len() != 0 {
t.Error("round 2: not at eof;", b.Len(), "bytes left")
}
// Now test with a running encoder/decoder pair that we recognize a type mismatch.
enc.Encode(et1);
if enc.state.err != nil {
t.Error("round 3: encoder fail:", enc.state.err)
}
newEt2 := new(ET2);
dec.Decode(newEt2);
if dec.state.err == nil {
t.Fatal("round 3: expected `bad type' error decoding ET2");
}
}
// Run one value through the encoder/decoder, but use the wrong type.
// Input is always an ET1; we compare it to whatever is under 'e'.
func badTypeCheck(e interface{}, shouldFail bool, msg string, t *testing.T) {
b := new(bytes.Buffer);
enc := NewEncoder(b);
et1 := new(ET1);
et1.a = 7;
et1.et2 = new(ET2);
enc.Encode(et1);
if enc.state.err != nil {
t.Error("encoder fail:", enc.state.err)
}
dec := NewDecoder(b);
dec.Decode(e);
if shouldFail && (dec.state.err == nil) {
t.Error("expected error for", msg);
}
if !shouldFail && (dec.state.err != nil) {
t.Error("unexpected error for", msg);
}
}
// Test that we recognize a bad type the first time.
func TestWrongTypeDecoder(t *testing.T) {
badTypeCheck(new(ET2), true, "no fields in common", t);
badTypeCheck(new(ET3), false, "different name of field", t);
badTypeCheck(new(ET4), true, "different type of field", t);
}
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