// 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" "encoding/hex" "fmt" "io" "math" "reflect" "sort" "strings" "testing" ) // Test basic operations in a safe manner. func TestBasicEncoderDecoder(t *testing.T) { var values = []any{ true, int(123), int8(123), int16(-12345), int32(123456), int64(-1234567), uint(123), uint8(123), uint16(12345), uint32(123456), uint64(1234567), uintptr(12345678), float32(1.2345), float64(1.2345678), complex64(1.2345 + 2.3456i), complex128(1.2345678 + 2.3456789i), []byte("hello"), string("hello"), } for _, value := range values { b := new(bytes.Buffer) enc := NewEncoder(b) err := enc.Encode(value) if err != nil { t.Error("encoder fail:", err) } dec := NewDecoder(b) result := reflect.New(reflect.TypeOf(value)) err = dec.Decode(result.Interface()) if err != nil { t.Fatalf("error decoding %T: %v:", reflect.TypeOf(value), err) } if !reflect.DeepEqual(value, result.Elem().Interface()) { t.Fatalf("%T: expected %v got %v", value, value, result.Elem().Interface()) } } } func TestEncodeIntSlice(t *testing.T) { s8 := []int8{1, 5, 12, 22, 35, 51, 70, 92, 117} s16 := []int16{145, 176, 210, 247, 287, 330, 376, 425, 477} s32 := []int32{532, 590, 651, 715, 782, 852, 925, 1001, 1080} s64 := []int64{1162, 1247, 1335, 1426, 1520, 1617, 1717, 1820, 1926} t.Run("int8", func(t *testing.T) { var sink bytes.Buffer enc := NewEncoder(&sink) enc.Encode(s8) dec := NewDecoder(&sink) res := make([]int8, 9) dec.Decode(&res) if !reflect.DeepEqual(s8, res) { t.Fatalf("EncodeIntSlice: expected %v, got %v", s8, res) } }) t.Run("int16", func(t *testing.T) { var sink bytes.Buffer enc := NewEncoder(&sink) enc.Encode(s16) dec := NewDecoder(&sink) res := make([]int16, 9) dec.Decode(&res) if !reflect.DeepEqual(s16, res) { t.Fatalf("EncodeIntSlice: expected %v, got %v", s16, res) } }) t.Run("int32", func(t *testing.T) { var sink bytes.Buffer enc := NewEncoder(&sink) enc.Encode(s32) dec := NewDecoder(&sink) res := make([]int32, 9) dec.Decode(&res) if !reflect.DeepEqual(s32, res) { t.Fatalf("EncodeIntSlice: expected %v, got %v", s32, res) } }) t.Run("int64", func(t *testing.T) { var sink bytes.Buffer enc := NewEncoder(&sink) enc.Encode(s64) dec := NewDecoder(&sink) res := make([]int64, 9) dec.Decode(&res) if !reflect.DeepEqual(s64, res) { t.Fatalf("EncodeIntSlice: expected %v, got %v", s64, res) } }) } type ET0 struct { A int B string } 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 float64 Next int } func TestEncoderDecoder(t *testing.T) { b := new(bytes.Buffer) enc := NewEncoder(b) et0 := new(ET0) et0.A = 7 et0.B = "gobs of fun" err := enc.Encode(et0) if err != nil { t.Error("encoder fail:", err) } //fmt.Printf("% x %q\n", b, b) //Debug(b) dec := NewDecoder(b) newEt0 := new(ET0) err = dec.Decode(newEt0) if err != nil { t.Fatal("error decoding ET0:", err) } if !reflect.DeepEqual(et0, newEt0) { t.Fatalf("invalid data for et0: expected %+v; got %+v", *et0, *newEt0) } if b.Len() != 0 { t.Error("not at eof;", b.Len(), "bytes left") } // t.FailNow() b = new(bytes.Buffer) enc = NewEncoder(b) et1 := new(ET1) et1.A = 7 et1.Et2 = new(ET2) err = enc.Encode(et1) if err != nil { t.Error("encoder fail:", err) } dec = NewDecoder(b) newEt1 := new(ET1) err = dec.Decode(newEt1) if err != nil { t.Fatal("error decoding ET1:", err) } if !reflect.DeepEqual(et1, newEt1) { t.Fatalf("invalid data for et1: expected %+v; got %+v", *et1, *newEt1) } if b.Len() != 0 { t.Error("not at eof;", b.Len(), "bytes left") } enc.Encode(et1) newEt1 = new(ET1) err = dec.Decode(newEt1) if err != nil { t.Fatal("round 2: error decoding ET1:", err) } if !reflect.DeepEqual(et1, newEt1) { t.Fatalf("round 2: invalid data for et1: expected %+v; got %+v", *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. err = enc.Encode(et1) if err != nil { t.Error("round 3: encoder fail:", err) } newEt2 := new(ET2) err = dec.Decode(newEt2) if 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 any, shouldFail bool, msg string, t *testing.T) { b := new(bytes.Buffer) enc := NewEncoder(b) et1 := new(ET1) et1.A = 7 et1.Et2 = new(ET2) err := enc.Encode(et1) if err != nil { t.Error("encoder fail:", err) } dec := NewDecoder(b) err = dec.Decode(e) if shouldFail && err == nil { t.Error("expected error for", msg) } if !shouldFail && err != nil { t.Error("unexpected error for", msg, err) } } // 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) } // Types not supported at top level by the Encoder. var unsupportedValues = []any{ make(chan int), func(a int) bool { return true }, } func TestUnsupported(t *testing.T) { var b bytes.Buffer enc := NewEncoder(&b) for _, v := range unsupportedValues { err := enc.Encode(v) if err == nil { t.Errorf("expected error for %T; got none", v) } } } func encAndDec(in, out any) error { b := new(bytes.Buffer) enc := NewEncoder(b) err := enc.Encode(in) if err != nil { return err } dec := NewDecoder(b) err = dec.Decode(out) if err != nil { return err } return nil } func TestTypeToPtrType(t *testing.T) { // Encode a T, decode a *T type Type0 struct { A int } t0 := Type0{7} t0p := new(Type0) if err := encAndDec(t0, t0p); err != nil { t.Error(err) } } func TestPtrTypeToType(t *testing.T) { // Encode a *T, decode a T type Type1 struct { A uint } t1p := &Type1{17} var t1 Type1 if err := encAndDec(t1, t1p); err != nil { t.Error(err) } } func TestTypeToPtrPtrPtrPtrType(t *testing.T) { type Type2 struct { A ****float64 } t2 := Type2{} t2.A = new(***float64) *t2.A = new(**float64) **t2.A = new(*float64) ***t2.A = new(float64) ****t2.A = 27.4 t2pppp := new(***Type2) if err := encAndDec(t2, t2pppp); err != nil { t.Fatal(err) } if ****(****t2pppp).A != ****t2.A { t.Errorf("wrong value after decode: %g not %g", ****(****t2pppp).A, ****t2.A) } } func TestSlice(t *testing.T) { type Type3 struct { A []string } t3p := &Type3{[]string{"hello", "world"}} var t3 Type3 if err := encAndDec(t3, t3p); err != nil { t.Error(err) } } func TestValueError(t *testing.T) { // Encode a *T, decode a T type Type4 struct { A int } t4p := &Type4{3} var t4 Type4 // note: not a pointer. if err := encAndDec(t4p, t4); err == nil || !strings.Contains(err.Error(), "pointer") { t.Error("expected error about pointer; got", err) } } func TestArray(t *testing.T) { type Type5 struct { A [3]string B [3]byte } type Type6 struct { A [2]string // can't hold t5.a } t5 := Type5{[3]string{"hello", ",", "world"}, [3]byte{1, 2, 3}} var t5p Type5 if err := encAndDec(t5, &t5p); err != nil { t.Error(err) } var t6 Type6 if err := encAndDec(t5, &t6); err == nil { t.Error("should fail with mismatched array sizes") } } func TestRecursiveMapType(t *testing.T) { type recursiveMap map[string]recursiveMap r1 := recursiveMap{"A": recursiveMap{"B": nil, "C": nil}, "D": nil} r2 := make(recursiveMap) if err := encAndDec(r1, &r2); err != nil { t.Error(err) } } func TestRecursiveSliceType(t *testing.T) { type recursiveSlice []recursiveSlice r1 := recursiveSlice{0: recursiveSlice{0: nil}, 1: nil} r2 := make(recursiveSlice, 0) if err := encAndDec(r1, &r2); err != nil { t.Error(err) } } // Regression test for bug: must send zero values inside arrays func TestDefaultsInArray(t *testing.T) { type Type7 struct { B []bool I []int S []string F []float64 } t7 := Type7{ []bool{false, false, true}, []int{0, 0, 1}, []string{"hi", "", "there"}, []float64{0, 0, 1}, } var t7p Type7 if err := encAndDec(t7, &t7p); err != nil { t.Error(err) } } var testInt int var testFloat32 float32 var testString string var testSlice []string var testMap map[string]int var testArray [7]int type SingleTest struct { in any out any err string } var singleTests = []SingleTest{ {17, &testInt, ""}, {float32(17.5), &testFloat32, ""}, {"bike shed", &testString, ""}, {[]string{"bike", "shed", "paint", "color"}, &testSlice, ""}, {map[string]int{"seven": 7, "twelve": 12}, &testMap, ""}, {[7]int{4, 55, 0, 0, 0, 0, 0}, &testArray, ""}, // case that once triggered a bug {[7]int{4, 55, 1, 44, 22, 66, 1234}, &testArray, ""}, // Decode errors {172, &testFloat32, "type"}, } func TestSingletons(t *testing.T) { b := new(bytes.Buffer) enc := NewEncoder(b) dec := NewDecoder(b) for _, test := range singleTests { b.Reset() err := enc.Encode(test.in) if err != nil { t.Errorf("error encoding %v: %s", test.in, err) continue } err = dec.Decode(test.out) switch { case err != nil && test.err == "": t.Errorf("error decoding %v: %s", test.in, err) continue case err == nil && test.err != "": t.Errorf("expected error decoding %v: %s", test.in, test.err) continue case err != nil && test.err != "": if !strings.Contains(err.Error(), test.err) { t.Errorf("wrong error decoding %v: wanted %s, got %v", test.in, test.err, err) } continue } // Get rid of the pointer in the rhs val := reflect.ValueOf(test.out).Elem().Interface() if !reflect.DeepEqual(test.in, val) { t.Errorf("decoding singleton: expected %v got %v", test.in, val) } } } func TestStructNonStruct(t *testing.T) { type Struct struct { A string } type NonStruct string s := Struct{"hello"} var sp Struct if err := encAndDec(s, &sp); err != nil { t.Error(err) } var ns NonStruct if err := encAndDec(s, &ns); err == nil { t.Error("should get error for struct/non-struct") } else if !strings.Contains(err.Error(), "type") { t.Error("for struct/non-struct expected type error; got", err) } // Now try the other way var nsp NonStruct if err := encAndDec(ns, &nsp); err != nil { t.Error(err) } if err := encAndDec(ns, &s); err == nil { t.Error("should get error for non-struct/struct") } else if !strings.Contains(err.Error(), "type") { t.Error("for non-struct/struct expected type error; got", err) } } type interfaceIndirectTestI interface { F() bool } type interfaceIndirectTestT struct{} func (this *interfaceIndirectTestT) F() bool { return true } // A version of a bug reported on golang-nuts. Also tests top-level // slice of interfaces. The issue was registering *T caused T to be // stored as the concrete type. func TestInterfaceIndirect(t *testing.T) { Register(&interfaceIndirectTestT{}) b := new(bytes.Buffer) w := []interfaceIndirectTestI{&interfaceIndirectTestT{}} err := NewEncoder(b).Encode(w) if err != nil { t.Fatal("encode error:", err) } var r []interfaceIndirectTestI err = NewDecoder(b).Decode(&r) if err != nil { t.Fatal("decode error:", err) } } // Now follow various tests that decode into things that can't represent the // encoded value, all of which should be legal. // Also, when the ignored object contains an interface value, it may define // types. Make sure that skipping the value still defines the types by using // the encoder/decoder pair to send a value afterwards. If an interface // is sent, its type in the test is always NewType0, so this checks that the // encoder and decoder don't skew with respect to type definitions. type Struct0 struct { I any } type NewType0 struct { S string } type ignoreTest struct { in, out any } var ignoreTests = []ignoreTest{ // Decode normal struct into an empty struct {&struct{ A int }{23}, &struct{}{}}, // Decode normal struct into a nil. {&struct{ A int }{23}, nil}, // Decode singleton string into a nil. {"hello, world", nil}, // Decode singleton slice into a nil. {[]int{1, 2, 3, 4}, nil}, // Decode struct containing an interface into a nil. {&Struct0{&NewType0{"value0"}}, nil}, // Decode singleton slice of interfaces into a nil. {[]any{"hi", &NewType0{"value1"}, 23}, nil}, } func TestDecodeIntoNothing(t *testing.T) { Register(new(NewType0)) for i, test := range ignoreTests { b := new(bytes.Buffer) enc := NewEncoder(b) err := enc.Encode(test.in) if err != nil { t.Errorf("%d: encode error %s:", i, err) continue } dec := NewDecoder(b) err = dec.Decode(test.out) if err != nil { t.Errorf("%d: decode error: %s", i, err) continue } // Now see if the encoder and decoder are in a consistent state. str := fmt.Sprintf("Value %d", i) err = enc.Encode(&NewType0{str}) if err != nil { t.Fatalf("%d: NewType0 encode error: %s", i, err) } ns := new(NewType0) err = dec.Decode(ns) if err != nil { t.Fatalf("%d: NewType0 decode error: %s", i, err) } if ns.S != str { t.Fatalf("%d: expected %q got %q", i, str, ns.S) } } } func TestIgnoreRecursiveType(t *testing.T) { // It's hard to build a self-contained test for this because // we can't build compatible types in one package with // different items so something is ignored. Here is // some data that represents, according to debug.go: // type definition { // slice "recursiveSlice" id=106 // elem id=106 // } data := []byte{ 0x1d, 0xff, 0xd3, 0x02, 0x01, 0x01, 0x0e, 0x72, 0x65, 0x63, 0x75, 0x72, 0x73, 0x69, 0x76, 0x65, 0x53, 0x6c, 0x69, 0x63, 0x65, 0x01, 0xff, 0xd4, 0x00, 0x01, 0xff, 0xd4, 0x00, 0x00, 0x07, 0xff, 0xd4, 0x00, 0x02, 0x01, 0x00, 0x00, } dec := NewDecoder(bytes.NewReader(data)) // Issue 10415: This caused infinite recursion. err := dec.Decode(nil) if err != nil { t.Fatal(err) } } // Another bug from golang-nuts, involving nested interfaces. type Bug0Outer struct { Bug0Field any } type Bug0Inner struct { A int } func TestNestedInterfaces(t *testing.T) { var buf bytes.Buffer e := NewEncoder(&buf) d := NewDecoder(&buf) Register(new(Bug0Outer)) Register(new(Bug0Inner)) f := &Bug0Outer{&Bug0Outer{&Bug0Inner{7}}} var v any = f err := e.Encode(&v) if err != nil { t.Fatal("Encode:", err) } err = d.Decode(&v) if err != nil { t.Fatal("Decode:", err) } // Make sure it decoded correctly. outer1, ok := v.(*Bug0Outer) if !ok { t.Fatalf("v not Bug0Outer: %T", v) } outer2, ok := outer1.Bug0Field.(*Bug0Outer) if !ok { t.Fatalf("v.Bug0Field not Bug0Outer: %T", outer1.Bug0Field) } inner, ok := outer2.Bug0Field.(*Bug0Inner) if !ok { t.Fatalf("v.Bug0Field.Bug0Field not Bug0Inner: %T", outer2.Bug0Field) } if inner.A != 7 { t.Fatalf("final value %d; expected %d", inner.A, 7) } } // The bugs keep coming. We forgot to send map subtypes before the map. type Bug1Elem struct { Name string Id int } type Bug1StructMap map[string]Bug1Elem func TestMapBug1(t *testing.T) { in := make(Bug1StructMap) in["val1"] = Bug1Elem{"elem1", 1} in["val2"] = Bug1Elem{"elem2", 2} b := new(bytes.Buffer) enc := NewEncoder(b) err := enc.Encode(in) if err != nil { t.Fatal("encode:", err) } dec := NewDecoder(b) out := make(Bug1StructMap) err = dec.Decode(&out) if err != nil { t.Fatal("decode:", err) } if !reflect.DeepEqual(in, out) { t.Errorf("mismatch: %v %v", in, out) } } func TestGobMapInterfaceEncode(t *testing.T) { m := map[string]any{ "up": uintptr(0), "i0": []int{-1}, "i1": []int8{-1}, "i2": []int16{-1}, "i3": []int32{-1}, "i4": []int64{-1}, "u0": []uint{1}, "u1": []uint8{1}, "u2": []uint16{1}, "u3": []uint32{1}, "u4": []uint64{1}, "f0": []float32{1}, "f1": []float64{1}, "c0": []complex64{complex(2, -2)}, "c1": []complex128{complex(2, float64(-2))}, "us": []uintptr{0}, "bo": []bool{false}, "st": []string{"s"}, } enc := NewEncoder(new(bytes.Buffer)) err := enc.Encode(m) if err != nil { t.Errorf("encode map: %s", err) } } func TestSliceReusesMemory(t *testing.T) { buf := new(bytes.Buffer) // Bytes { x := []byte("abcd") enc := NewEncoder(buf) err := enc.Encode(x) if err != nil { t.Errorf("bytes: encode: %s", err) } // Decode into y, which is big enough. y := []byte("ABCDE") addr := &y[0] dec := NewDecoder(buf) err = dec.Decode(&y) if err != nil { t.Fatal("bytes: decode:", err) } if !bytes.Equal(x, y) { t.Errorf("bytes: expected %q got %q\n", x, y) } if addr != &y[0] { t.Errorf("bytes: unnecessary reallocation") } } // general slice { x := []rune("abcd") enc := NewEncoder(buf) err := enc.Encode(x) if err != nil { t.Errorf("ints: encode: %s", err) } // Decode into y, which is big enough. y := []rune("ABCDE") addr := &y[0] dec := NewDecoder(buf) err = dec.Decode(&y) if err != nil { t.Fatal("ints: decode:", err) } if !reflect.DeepEqual(x, y) { t.Errorf("ints: expected %q got %q\n", x, y) } if addr != &y[0] { t.Errorf("ints: unnecessary reallocation") } } } // Used to crash: negative count in recvMessage. func TestBadCount(t *testing.T) { b := []byte{0xfb, 0xa5, 0x82, 0x2f, 0xca, 0x1} if err := NewDecoder(bytes.NewReader(b)).Decode(nil); err == nil { t.Error("expected error from bad count") } else if err.Error() != errBadCount.Error() { t.Error("expected bad count error; got", err) } } // Verify that sequential Decoders built on a single input will // succeed if the input implements ReadByte and there is no // type information in the stream. func TestSequentialDecoder(t *testing.T) { b := new(bytes.Buffer) enc := NewEncoder(b) const count = 10 for i := 0; i < count; i++ { s := fmt.Sprintf("%d", i) if err := enc.Encode(s); err != nil { t.Error("encoder fail:", err) } } for i := 0; i < count; i++ { dec := NewDecoder(b) var s string if err := dec.Decode(&s); err != nil { t.Fatal("decoder fail:", err) } if s != fmt.Sprintf("%d", i) { t.Fatalf("decode expected %d got %s", i, s) } } } // Should be able to have unrepresentable fields (chan, func, *chan etc.); we just ignore them. type Bug2 struct { A int C chan int CP *chan int F func() FPP **func() } func TestChanFuncIgnored(t *testing.T) { c := make(chan int) f := func() {} fp := &f b0 := Bug2{23, c, &c, f, &fp} var buf bytes.Buffer enc := NewEncoder(&buf) if err := enc.Encode(b0); err != nil { t.Fatal("error encoding:", err) } var b1 Bug2 err := NewDecoder(&buf).Decode(&b1) if err != nil { t.Fatal("decode:", err) } if b1.A != b0.A { t.Fatalf("got %d want %d", b1.A, b0.A) } if b1.C != nil || b1.CP != nil || b1.F != nil || b1.FPP != nil { t.Fatal("unexpected value for chan or func") } } func TestSliceIncompatibility(t *testing.T) { var in = []byte{1, 2, 3} var out []int if err := encAndDec(in, &out); err == nil { t.Error("expected compatibility error") } } // Mutually recursive slices of structs caused problems. type Bug3 struct { Num int Children []*Bug3 } func TestGobPtrSlices(t *testing.T) { in := []*Bug3{ {1, nil}, {2, nil}, } b := new(bytes.Buffer) err := NewEncoder(b).Encode(&in) if err != nil { t.Fatal("encode:", err) } var out []*Bug3 err = NewDecoder(b).Decode(&out) if err != nil { t.Fatal("decode:", err) } if !reflect.DeepEqual(in, out) { t.Fatalf("got %v; wanted %v", out, in) } } // getDecEnginePtr cached engine for ut.base instead of ut.user so we passed // a *map and then tried to reuse its engine to decode the inner map. func TestPtrToMapOfMap(t *testing.T) { Register(make(map[string]any)) subdata := make(map[string]any) subdata["bar"] = "baz" data := make(map[string]any) data["foo"] = subdata b := new(bytes.Buffer) err := NewEncoder(b).Encode(data) if err != nil { t.Fatal("encode:", err) } var newData map[string]any err = NewDecoder(b).Decode(&newData) if err != nil { t.Fatal("decode:", err) } if !reflect.DeepEqual(data, newData) { t.Fatalf("expected %v got %v", data, newData) } } // Test that untyped nils generate an error, not a panic. // See Issue 16204. func TestCatchInvalidNilValue(t *testing.T) { encodeErr, panicErr := encodeAndRecover(nil) if panicErr != nil { t.Fatalf("panicErr=%v, should not panic encoding untyped nil", panicErr) } if encodeErr == nil { t.Errorf("got err=nil, want non-nil error when encoding untyped nil value") } else if !strings.Contains(encodeErr.Error(), "nil value") { t.Errorf("expected 'nil value' error; got err=%v", encodeErr) } } // A top-level nil pointer generates a panic with a helpful string-valued message. func TestTopLevelNilPointer(t *testing.T) { var ip *int encodeErr, panicErr := encodeAndRecover(ip) if encodeErr != nil { t.Fatal("error in encode:", encodeErr) } if panicErr == nil { t.Fatal("top-level nil pointer did not panic") } errMsg := panicErr.Error() if !strings.Contains(errMsg, "nil pointer") { t.Fatal("expected nil pointer error, got:", errMsg) } } func encodeAndRecover(value any) (encodeErr, panicErr error) { defer func() { e := recover() if e != nil { switch err := e.(type) { case error: panicErr = err default: panicErr = fmt.Errorf("%v", err) } } }() encodeErr = NewEncoder(io.Discard).Encode(value) return } func TestNilPointerPanics(t *testing.T) { var ( nilStringPtr *string intMap = make(map[int]int) intMapPtr = &intMap nilIntMapPtr *map[int]int zero int nilBoolChannel chan bool nilBoolChannelPtr *chan bool nilStringSlice []string stringSlice = make([]string, 1) nilStringSlicePtr *[]string ) testCases := []struct { value any mustPanic bool }{ {nilStringPtr, true}, {intMap, false}, {intMapPtr, false}, {nilIntMapPtr, true}, {zero, false}, {nilStringSlice, false}, {stringSlice, false}, {nilStringSlicePtr, true}, {nilBoolChannel, false}, {nilBoolChannelPtr, true}, } for _, tt := range testCases { _, panicErr := encodeAndRecover(tt.value) if tt.mustPanic { if panicErr == nil { t.Errorf("expected panic with input %#v, did not panic", tt.value) } continue } if panicErr != nil { t.Fatalf("expected no panic with input %#v, got panic=%v", tt.value, panicErr) } } } func TestNilPointerInsideInterface(t *testing.T) { var ip *int si := struct { I any }{ I: ip, } buf := new(bytes.Buffer) err := NewEncoder(buf).Encode(si) if err == nil { t.Fatal("expected error, got none") } errMsg := err.Error() if !strings.Contains(errMsg, "nil pointer") || !strings.Contains(errMsg, "interface") { t.Fatal("expected error about nil pointer and interface, got:", errMsg) } } type Bug4Public struct { Name string Secret Bug4Secret } type Bug4Secret struct { a int // error: no exported fields. } // Test that a failed compilation doesn't leave around an executable encoder. // Issue 3723. func TestMultipleEncodingsOfBadType(t *testing.T) { x := Bug4Public{ Name: "name", Secret: Bug4Secret{1}, } buf := new(bytes.Buffer) enc := NewEncoder(buf) err := enc.Encode(x) if err == nil { t.Fatal("first encoding: expected error") } buf.Reset() enc = NewEncoder(buf) err = enc.Encode(x) if err == nil { t.Fatal("second encoding: expected error") } if !strings.Contains(err.Error(), "no exported fields") { t.Errorf("expected error about no exported fields; got %v", err) } } // There was an error check comparing the length of the input with the // length of the slice being decoded. It was wrong because the next // thing in the input might be a type definition, which would lead to // an incorrect length check. This test reproduces the corner case. type Z struct { } func Test29ElementSlice(t *testing.T) { Register(Z{}) src := make([]any, 100) // Size needs to be bigger than size of type definition. for i := range src { src[i] = Z{} } buf := new(bytes.Buffer) err := NewEncoder(buf).Encode(src) if err != nil { t.Fatalf("encode: %v", err) return } var dst []any err = NewDecoder(buf).Decode(&dst) if err != nil { t.Errorf("decode: %v", err) return } } // Don't crash, just give error when allocating a huge slice. // Issue 8084. func TestErrorForHugeSlice(t *testing.T) { // Encode an int slice. buf := new(bytes.Buffer) slice := []int{1, 1, 1, 1, 1, 1, 1, 1, 1, 1} err := NewEncoder(buf).Encode(slice) if err != nil { t.Fatal("encode:", err) } // Reach into the buffer and smash the count to make the encoded slice very long. buf.Bytes()[buf.Len()-len(slice)-1] = 0xfa // Decode and see error. err = NewDecoder(buf).Decode(&slice) if err == nil { t.Fatal("decode: no error") } if !strings.Contains(err.Error(), "slice too big") { t.Fatalf("decode: expected slice too big error, got %s", err.Error()) } } type badDataTest struct { input string // The input encoded as a hex string. error string // A substring of the error that should result. data any // What to decode into. } var badDataTests = []badDataTest{ {"", "EOF", nil}, {"7F6869", "unexpected EOF", nil}, {"036e6f77206973207468652074696d6520666f7220616c6c20676f6f64206d656e", "unknown type id", new(ET2)}, {"0424666f6f", "field numbers out of bounds", new(ET2)}, // Issue 6323. {"05100028557b02027f8302", "interface encoding", nil}, // Issue 10270. // Issue 10273. {"130a00fb5dad0bf8ff020263e70002fa28020202a89859", "slice length too large", nil}, {"0f1000fb285d003316020735ff023a65c5", "interface encoding", nil}, {"03fffb0616fffc00f902ff02ff03bf005d02885802a311a8120228022c028ee7", "GobDecoder", nil}, // Issue 10491. {"10fe010f020102fe01100001fe010e000016fe010d030102fe010e00010101015801fe01100000000bfe011000f85555555555555555", "exceeds input size", nil}, } // TestBadData tests that various problems caused by malformed input // are caught as errors and do not cause panics. func TestBadData(t *testing.T) { for i, test := range badDataTests { data, err := hex.DecodeString(test.input) if err != nil { t.Fatalf("#%d: hex error: %s", i, err) } d := NewDecoder(bytes.NewReader(data)) err = d.Decode(test.data) if err == nil { t.Errorf("decode: no error") continue } if !strings.Contains(err.Error(), test.error) { t.Errorf("#%d: decode: expected %q error, got %s", i, test.error, err.Error()) } } } func TestDecodeErrorMultipleTypes(t *testing.T) { type Test struct { A string B int } var b bytes.Buffer NewEncoder(&b).Encode(Test{"one", 1}) var result, result2 Test dec := NewDecoder(&b) err := dec.Decode(&result) if err != nil { t.Errorf("decode: unexpected error %v", err) } b.Reset() NewEncoder(&b).Encode(Test{"two", 2}) err = dec.Decode(&result2) if err == nil { t.Errorf("decode: expected duplicate type error, got nil") } else if !strings.Contains(err.Error(), "duplicate type") { t.Errorf("decode: expected duplicate type error, got %s", err.Error()) } } // Issue 24075 func TestMarshalFloatMap(t *testing.T) { nan1 := math.NaN() nan2 := math.Float64frombits(math.Float64bits(nan1) ^ 1) // A different NaN in the same class. in := map[float64]string{ nan1: "a", nan1: "b", nan2: "c", } var b bytes.Buffer enc := NewEncoder(&b) if err := enc.Encode(in); err != nil { t.Errorf("Encode : %v", err) } out := map[float64]string{} dec := NewDecoder(&b) if err := dec.Decode(&out); err != nil { t.Fatalf("Decode : %v", err) } type mapEntry struct { keyBits uint64 value string } readMap := func(m map[float64]string) (entries []mapEntry) { for k, v := range m { entries = append(entries, mapEntry{math.Float64bits(k), v}) } sort.Slice(entries, func(i, j int) bool { ei, ej := entries[i], entries[j] if ei.keyBits != ej.keyBits { return ei.keyBits < ej.keyBits } return ei.value < ej.value }) return entries } got := readMap(out) want := readMap(in) if !reflect.DeepEqual(got, want) { t.Fatalf("\nEncode: %v\nDecode: %v", want, got) } } func TestDecodePartial(t *testing.T) { type T struct { X []int Y string } var buf bytes.Buffer t1 := T{X: []int{1, 2, 3}, Y: "foo"} t2 := T{X: []int{4, 5, 6}, Y: "bar"} enc := NewEncoder(&buf) t1start := 0 if err := enc.Encode(&t1); err != nil { t.Fatal(err) } t2start := buf.Len() if err := enc.Encode(&t2); err != nil { t.Fatal(err) } data := buf.Bytes() for i := 0; i <= len(data); i++ { bufr := bytes.NewReader(data[:i]) // Decode both values, stopping at the first error. var t1b, t2b T dec := NewDecoder(bufr) var err error err = dec.Decode(&t1b) if err == nil { err = dec.Decode(&t2b) } switch i { case t1start, t2start: // Either the first or the second Decode calls had zero input. if err != io.EOF { t.Errorf("%d/%d: expected io.EOF: %v", i, len(data), err) } case len(data): // We reached the end of the entire input. if err != nil { t.Errorf("%d/%d: unexpected error: %v", i, len(data), err) } if !reflect.DeepEqual(t1b, t1) { t.Fatalf("t1 value mismatch: got %v, want %v", t1b, t1) } if !reflect.DeepEqual(t2b, t2) { t.Fatalf("t2 value mismatch: got %v, want %v", t2b, t2) } default: // In between, we must see io.ErrUnexpectedEOF. // The decoder used to erroneously return io.EOF in some cases here, // such as if the input was cut off right after some type specs, // but before any value was actually transmitted. if err != io.ErrUnexpectedEOF { t.Errorf("%d/%d: expected io.ErrUnexpectedEOF: %v", i, len(data), err) } } } } func TestDecoderOverflow(t *testing.T) { // Issue 55337. dec := NewDecoder(bytes.NewReader([]byte{ 0x12, 0xff, 0xff, 0x2, 0x2, 0x20, 0x0, 0xf8, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x20, 0x20, 0x20, 0x20, 0x20, })) var r interface{} err := dec.Decode(r) if err == nil { t.Fatalf("expected an error") } }