// 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 reflect_test import ( "bytes" "encoding/base64" "flag" "fmt" "io" "math/rand" "os" . "reflect" "runtime" "sort" "strconv" "strings" "sync" "testing" "time" "unsafe" ) func TestBool(t *testing.T) { v := ValueOf(true) if v.Bool() != true { t.Fatal("ValueOf(true).Bool() = false") } } type integer int type T struct { a int b float64 c string d *int } type pair struct { i interface{} s string } func isDigit(c uint8) bool { return '0' <= c && c <= '9' } func assert(t *testing.T, s, want string) { if s != want { t.Errorf("have %#q want %#q", s, want) } } func typestring(i interface{}) string { return TypeOf(i).String() } var typeTests = []pair{ {struct{ x int }{}, "int"}, {struct{ x int8 }{}, "int8"}, {struct{ x int16 }{}, "int16"}, {struct{ x int32 }{}, "int32"}, {struct{ x int64 }{}, "int64"}, {struct{ x uint }{}, "uint"}, {struct{ x uint8 }{}, "uint8"}, {struct{ x uint16 }{}, "uint16"}, {struct{ x uint32 }{}, "uint32"}, {struct{ x uint64 }{}, "uint64"}, {struct{ x float32 }{}, "float32"}, {struct{ x float64 }{}, "float64"}, {struct{ x int8 }{}, "int8"}, {struct{ x (**int8) }{}, "**int8"}, {struct{ x (**integer) }{}, "**reflect_test.integer"}, {struct{ x ([32]int32) }{}, "[32]int32"}, {struct{ x ([]int8) }{}, "[]int8"}, {struct{ x (map[string]int32) }{}, "map[string]int32"}, {struct{ x (chan<- string) }{}, "chan<- string"}, {struct { x struct { c chan *int32 d float32 } }{}, "struct { c chan *int32; d float32 }", }, {struct{ x (func(a int8, b int32)) }{}, "func(int8, int32)"}, {struct { x struct { c func(chan *integer, *int8) } }{}, "struct { c func(chan *reflect_test.integer, *int8) }", }, {struct { x struct { a int8 b int32 } }{}, "struct { a int8; b int32 }", }, {struct { x struct { a int8 b int8 c int32 } }{}, "struct { a int8; b int8; c int32 }", }, {struct { x struct { a int8 b int8 c int8 d int32 } }{}, "struct { a int8; b int8; c int8; d int32 }", }, {struct { x struct { a int8 b int8 c int8 d int8 e int32 } }{}, "struct { a int8; b int8; c int8; d int8; e int32 }", }, {struct { x struct { a int8 b int8 c int8 d int8 e int8 f int32 } }{}, "struct { a int8; b int8; c int8; d int8; e int8; f int32 }", }, {struct { x struct { a int8 `reflect:"hi there"` } }{}, `struct { a int8 "reflect:\"hi there\"" }`, }, {struct { x struct { a int8 `reflect:"hi \x00there\t\n\"\\"` } }{}, `struct { a int8 "reflect:\"hi \\x00there\\t\\n\\\"\\\\\"" }`, }, {struct { x struct { f func(args ...int) } }{}, "struct { f func(...int) }", }, {struct { x (interface { a(func(func(int) int) func(func(int)) int) b() }) }{}, "interface { reflect_test.a(func(func(int) int) func(func(int)) int); reflect_test.b() }", }, } var valueTests = []pair{ {new(int), "132"}, {new(int8), "8"}, {new(int16), "16"}, {new(int32), "32"}, {new(int64), "64"}, {new(uint), "132"}, {new(uint8), "8"}, {new(uint16), "16"}, {new(uint32), "32"}, {new(uint64), "64"}, {new(float32), "256.25"}, {new(float64), "512.125"}, {new(complex64), "532.125+10i"}, {new(complex128), "564.25+1i"}, {new(string), "stringy cheese"}, {new(bool), "true"}, {new(*int8), "*int8(0)"}, {new(**int8), "**int8(0)"}, {new([5]int32), "[5]int32{0, 0, 0, 0, 0}"}, {new(**integer), "**reflect_test.integer(0)"}, {new(map[string]int32), "map[string]int32{<can't iterate on maps>}"}, {new(chan<- string), "chan<- string"}, {new(func(a int8, b int32)), "func(int8, int32)(0)"}, {new(struct { c chan *int32 d float32 }), "struct { c chan *int32; d float32 }{chan *int32, 0}", }, {new(struct{ c func(chan *integer, *int8) }), "struct { c func(chan *reflect_test.integer, *int8) }{func(chan *reflect_test.integer, *int8)(0)}", }, {new(struct { a int8 b int32 }), "struct { a int8; b int32 }{0, 0}", }, {new(struct { a int8 b int8 c int32 }), "struct { a int8; b int8; c int32 }{0, 0, 0}", }, } func testType(t *testing.T, i int, typ Type, want string) { s := typ.String() if s != want { t.Errorf("#%d: have %#q, want %#q", i, s, want) } } func TestTypes(t *testing.T) { for i, tt := range typeTests { testType(t, i, ValueOf(tt.i).Field(0).Type(), tt.s) } } func TestSet(t *testing.T) { for i, tt := range valueTests { v := ValueOf(tt.i) v = v.Elem() switch v.Kind() { case Int: v.SetInt(132) case Int8: v.SetInt(8) case Int16: v.SetInt(16) case Int32: v.SetInt(32) case Int64: v.SetInt(64) case Uint: v.SetUint(132) case Uint8: v.SetUint(8) case Uint16: v.SetUint(16) case Uint32: v.SetUint(32) case Uint64: v.SetUint(64) case Float32: v.SetFloat(256.25) case Float64: v.SetFloat(512.125) case Complex64: v.SetComplex(532.125 + 10i) case Complex128: v.SetComplex(564.25 + 1i) case String: v.SetString("stringy cheese") case Bool: v.SetBool(true) } s := valueToString(v) if s != tt.s { t.Errorf("#%d: have %#q, want %#q", i, s, tt.s) } } } func TestSetValue(t *testing.T) { for i, tt := range valueTests { v := ValueOf(tt.i).Elem() switch v.Kind() { case Int: v.Set(ValueOf(int(132))) case Int8: v.Set(ValueOf(int8(8))) case Int16: v.Set(ValueOf(int16(16))) case Int32: v.Set(ValueOf(int32(32))) case Int64: v.Set(ValueOf(int64(64))) case Uint: v.Set(ValueOf(uint(132))) case Uint8: v.Set(ValueOf(uint8(8))) case Uint16: v.Set(ValueOf(uint16(16))) case Uint32: v.Set(ValueOf(uint32(32))) case Uint64: v.Set(ValueOf(uint64(64))) case Float32: v.Set(ValueOf(float32(256.25))) case Float64: v.Set(ValueOf(512.125)) case Complex64: v.Set(ValueOf(complex64(532.125 + 10i))) case Complex128: v.Set(ValueOf(complex128(564.25 + 1i))) case String: v.Set(ValueOf("stringy cheese")) case Bool: v.Set(ValueOf(true)) } s := valueToString(v) if s != tt.s { t.Errorf("#%d: have %#q, want %#q", i, s, tt.s) } } } var _i = 7 var valueToStringTests = []pair{ {123, "123"}, {123.5, "123.5"}, {byte(123), "123"}, {"abc", "abc"}, {T{123, 456.75, "hello", &_i}, "reflect_test.T{123, 456.75, hello, *int(&7)}"}, {new(chan *T), "*chan *reflect_test.T(&chan *reflect_test.T)"}, {[10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, "[10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}"}, {&[10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, "*[10]int(&[10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10})"}, {[]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, "[]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}"}, {&[]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, "*[]int(&[]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10})"}, } func TestValueToString(t *testing.T) { for i, test := range valueToStringTests { s := valueToString(ValueOf(test.i)) if s != test.s { t.Errorf("#%d: have %#q, want %#q", i, s, test.s) } } } func TestArrayElemSet(t *testing.T) { v := ValueOf(&[10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}).Elem() v.Index(4).SetInt(123) s := valueToString(v) const want = "[10]int{1, 2, 3, 4, 123, 6, 7, 8, 9, 10}" if s != want { t.Errorf("[10]int: have %#q want %#q", s, want) } v = ValueOf([]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}) v.Index(4).SetInt(123) s = valueToString(v) const want1 = "[]int{1, 2, 3, 4, 123, 6, 7, 8, 9, 10}" if s != want1 { t.Errorf("[]int: have %#q want %#q", s, want1) } } func TestPtrPointTo(t *testing.T) { var ip *int32 var i int32 = 1234 vip := ValueOf(&ip) vi := ValueOf(&i).Elem() vip.Elem().Set(vi.Addr()) if *ip != 1234 { t.Errorf("got %d, want 1234", *ip) } ip = nil vp := ValueOf(&ip).Elem() vp.Set(Zero(vp.Type())) if ip != nil { t.Errorf("got non-nil (%p), want nil", ip) } } func TestPtrSetNil(t *testing.T) { var i int32 = 1234 ip := &i vip := ValueOf(&ip) vip.Elem().Set(Zero(vip.Elem().Type())) if ip != nil { t.Errorf("got non-nil (%d), want nil", *ip) } } func TestMapSetNil(t *testing.T) { m := make(map[string]int) vm := ValueOf(&m) vm.Elem().Set(Zero(vm.Elem().Type())) if m != nil { t.Errorf("got non-nil (%p), want nil", m) } } func TestAll(t *testing.T) { testType(t, 1, TypeOf((int8)(0)), "int8") testType(t, 2, TypeOf((*int8)(nil)).Elem(), "int8") typ := TypeOf((*struct { c chan *int32 d float32 })(nil)) testType(t, 3, typ, "*struct { c chan *int32; d float32 }") etyp := typ.Elem() testType(t, 4, etyp, "struct { c chan *int32; d float32 }") styp := etyp f := styp.Field(0) testType(t, 5, f.Type, "chan *int32") f, present := styp.FieldByName("d") if !present { t.Errorf("FieldByName says present field is absent") } testType(t, 6, f.Type, "float32") f, present = styp.FieldByName("absent") if present { t.Errorf("FieldByName says absent field is present") } typ = TypeOf([32]int32{}) testType(t, 7, typ, "[32]int32") testType(t, 8, typ.Elem(), "int32") typ = TypeOf((map[string]*int32)(nil)) testType(t, 9, typ, "map[string]*int32") mtyp := typ testType(t, 10, mtyp.Key(), "string") testType(t, 11, mtyp.Elem(), "*int32") typ = TypeOf((chan<- string)(nil)) testType(t, 12, typ, "chan<- string") testType(t, 13, typ.Elem(), "string") // make sure tag strings are not part of element type typ = TypeOf(struct { d []uint32 `reflect:"TAG"` }{}).Field(0).Type testType(t, 14, typ, "[]uint32") } func TestInterfaceGet(t *testing.T) { var inter struct { E interface{} } inter.E = 123.456 v1 := ValueOf(&inter) v2 := v1.Elem().Field(0) assert(t, v2.Type().String(), "interface {}") i2 := v2.Interface() v3 := ValueOf(i2) assert(t, v3.Type().String(), "float64") } func TestInterfaceValue(t *testing.T) { var inter struct { E interface{} } inter.E = 123.456 v1 := ValueOf(&inter) v2 := v1.Elem().Field(0) assert(t, v2.Type().String(), "interface {}") v3 := v2.Elem() assert(t, v3.Type().String(), "float64") i3 := v2.Interface() if _, ok := i3.(float64); !ok { t.Error("v2.Interface() did not return float64, got ", TypeOf(i3)) } } func TestFunctionValue(t *testing.T) { var x interface{} = func() {} v := ValueOf(x) if fmt.Sprint(v.Interface()) != fmt.Sprint(x) { t.Fatalf("TestFunction returned wrong pointer") } assert(t, v.Type().String(), "func()") } var appendTests = []struct { orig, extra []int }{ {make([]int, 2, 4), []int{22}}, {make([]int, 2, 4), []int{22, 33, 44}}, } func sameInts(x, y []int) bool { if len(x) != len(y) { return false } for i, xx := range x { if xx != y[i] { return false } } return true } func TestAppend(t *testing.T) { for i, test := range appendTests { origLen, extraLen := len(test.orig), len(test.extra) want := append(test.orig, test.extra...) // Convert extra from []int to []Value. e0 := make([]Value, len(test.extra)) for j, e := range test.extra { e0[j] = ValueOf(e) } // Convert extra from []int to *SliceValue. e1 := ValueOf(test.extra) // Test Append. a0 := ValueOf(test.orig) have0 := Append(a0, e0...).Interface().([]int) if !sameInts(have0, want) { t.Errorf("Append #%d: have %v, want %v (%p %p)", i, have0, want, test.orig, have0) } // Check that the orig and extra slices were not modified. if len(test.orig) != origLen { t.Errorf("Append #%d origLen: have %v, want %v", i, len(test.orig), origLen) } if len(test.extra) != extraLen { t.Errorf("Append #%d extraLen: have %v, want %v", i, len(test.extra), extraLen) } // Test AppendSlice. a1 := ValueOf(test.orig) have1 := AppendSlice(a1, e1).Interface().([]int) if !sameInts(have1, want) { t.Errorf("AppendSlice #%d: have %v, want %v", i, have1, want) } // Check that the orig and extra slices were not modified. if len(test.orig) != origLen { t.Errorf("AppendSlice #%d origLen: have %v, want %v", i, len(test.orig), origLen) } if len(test.extra) != extraLen { t.Errorf("AppendSlice #%d extraLen: have %v, want %v", i, len(test.extra), extraLen) } } } func TestCopy(t *testing.T) { a := []int{1, 2, 3, 4, 10, 9, 8, 7} b := []int{11, 22, 33, 44, 1010, 99, 88, 77, 66, 55, 44} c := []int{11, 22, 33, 44, 1010, 99, 88, 77, 66, 55, 44} for i := 0; i < len(b); i++ { if b[i] != c[i] { t.Fatalf("b != c before test") } } a1 := a b1 := b aa := ValueOf(&a1).Elem() ab := ValueOf(&b1).Elem() for tocopy := 1; tocopy <= 7; tocopy++ { aa.SetLen(tocopy) Copy(ab, aa) aa.SetLen(8) for i := 0; i < tocopy; i++ { if a[i] != b[i] { t.Errorf("(i) tocopy=%d a[%d]=%d, b[%d]=%d", tocopy, i, a[i], i, b[i]) } } for i := tocopy; i < len(b); i++ { if b[i] != c[i] { if i < len(a) { t.Errorf("(ii) tocopy=%d a[%d]=%d, b[%d]=%d, c[%d]=%d", tocopy, i, a[i], i, b[i], i, c[i]) } else { t.Errorf("(iii) tocopy=%d b[%d]=%d, c[%d]=%d", tocopy, i, b[i], i, c[i]) } } else { t.Logf("tocopy=%d elem %d is okay\n", tocopy, i) } } } } func TestCopyArray(t *testing.T) { a := [8]int{1, 2, 3, 4, 10, 9, 8, 7} b := [11]int{11, 22, 33, 44, 1010, 99, 88, 77, 66, 55, 44} c := b aa := ValueOf(&a).Elem() ab := ValueOf(&b).Elem() Copy(ab, aa) for i := 0; i < len(a); i++ { if a[i] != b[i] { t.Errorf("(i) a[%d]=%d, b[%d]=%d", i, a[i], i, b[i]) } } for i := len(a); i < len(b); i++ { if b[i] != c[i] { t.Errorf("(ii) b[%d]=%d, c[%d]=%d", i, b[i], i, c[i]) } else { t.Logf("elem %d is okay\n", i) } } } func TestBigUnnamedStruct(t *testing.T) { b := struct{ a, b, c, d int64 }{1, 2, 3, 4} v := ValueOf(b) b1 := v.Interface().(struct { a, b, c, d int64 }) if b1.a != b.a || b1.b != b.b || b1.c != b.c || b1.d != b.d { t.Errorf("ValueOf(%v).Interface().(*Big) = %v", b, b1) } } type big struct { a, b, c, d, e int64 } func TestBigStruct(t *testing.T) { b := big{1, 2, 3, 4, 5} v := ValueOf(b) b1 := v.Interface().(big) if b1.a != b.a || b1.b != b.b || b1.c != b.c || b1.d != b.d || b1.e != b.e { t.Errorf("ValueOf(%v).Interface().(big) = %v", b, b1) } } type Basic struct { x int y float32 } type NotBasic Basic type DeepEqualTest struct { a, b interface{} eq bool } // Simple functions for DeepEqual tests. var ( fn1 func() // nil. fn2 func() // nil. fn3 = func() { fn1() } // Not nil. ) var deepEqualTests = []DeepEqualTest{ // Equalities {nil, nil, true}, {1, 1, true}, {int32(1), int32(1), true}, {0.5, 0.5, true}, {float32(0.5), float32(0.5), true}, {"hello", "hello", true}, {make([]int, 10), make([]int, 10), true}, {&[3]int{1, 2, 3}, &[3]int{1, 2, 3}, true}, {Basic{1, 0.5}, Basic{1, 0.5}, true}, {error(nil), error(nil), true}, {map[int]string{1: "one", 2: "two"}, map[int]string{2: "two", 1: "one"}, true}, {fn1, fn2, true}, // Inequalities {1, 2, false}, {int32(1), int32(2), false}, {0.5, 0.6, false}, {float32(0.5), float32(0.6), false}, {"hello", "hey", false}, {make([]int, 10), make([]int, 11), false}, {&[3]int{1, 2, 3}, &[3]int{1, 2, 4}, false}, {Basic{1, 0.5}, Basic{1, 0.6}, false}, {Basic{1, 0}, Basic{2, 0}, false}, {map[int]string{1: "one", 3: "two"}, map[int]string{2: "two", 1: "one"}, false}, {map[int]string{1: "one", 2: "txo"}, map[int]string{2: "two", 1: "one"}, false}, {map[int]string{1: "one"}, map[int]string{2: "two", 1: "one"}, false}, {map[int]string{2: "two", 1: "one"}, map[int]string{1: "one"}, false}, {nil, 1, false}, {1, nil, false}, {fn1, fn3, false}, {fn3, fn3, false}, {[][]int{{1}}, [][]int{{2}}, false}, // Nil vs empty: not the same. {[]int{}, []int(nil), false}, {[]int{}, []int{}, true}, {[]int(nil), []int(nil), true}, {map[int]int{}, map[int]int(nil), false}, {map[int]int{}, map[int]int{}, true}, {map[int]int(nil), map[int]int(nil), true}, // Mismatched types {1, 1.0, false}, {int32(1), int64(1), false}, {0.5, "hello", false}, {[]int{1, 2, 3}, [3]int{1, 2, 3}, false}, {&[3]interface{}{1, 2, 4}, &[3]interface{}{1, 2, "s"}, false}, {Basic{1, 0.5}, NotBasic{1, 0.5}, false}, {map[uint]string{1: "one", 2: "two"}, map[int]string{2: "two", 1: "one"}, false}, } func TestDeepEqual(t *testing.T) { for _, test := range deepEqualTests { if r := DeepEqual(test.a, test.b); r != test.eq { t.Errorf("DeepEqual(%v, %v) = %v, want %v", test.a, test.b, r, test.eq) } } } func TestTypeOf(t *testing.T) { // Special case for nil if typ := TypeOf(nil); typ != nil { t.Errorf("expected nil type for nil value; got %v", typ) } for _, test := range deepEqualTests { v := ValueOf(test.a) if !v.IsValid() { continue } typ := TypeOf(test.a) if typ != v.Type() { t.Errorf("TypeOf(%v) = %v, but ValueOf(%v).Type() = %v", test.a, typ, test.a, v.Type()) } } } type Recursive struct { x int r *Recursive } func TestDeepEqualRecursiveStruct(t *testing.T) { a, b := new(Recursive), new(Recursive) *a = Recursive{12, a} *b = Recursive{12, b} if !DeepEqual(a, b) { t.Error("DeepEqual(recursive same) = false, want true") } } type _Complex struct { a int b [3]*_Complex c *string d map[float64]float64 } func TestDeepEqualComplexStruct(t *testing.T) { m := make(map[float64]float64) stra, strb := "hello", "hello" a, b := new(_Complex), new(_Complex) *a = _Complex{5, [3]*_Complex{a, b, a}, &stra, m} *b = _Complex{5, [3]*_Complex{b, a, a}, &strb, m} if !DeepEqual(a, b) { t.Error("DeepEqual(complex same) = false, want true") } } func TestDeepEqualComplexStructInequality(t *testing.T) { m := make(map[float64]float64) stra, strb := "hello", "helloo" // Difference is here a, b := new(_Complex), new(_Complex) *a = _Complex{5, [3]*_Complex{a, b, a}, &stra, m} *b = _Complex{5, [3]*_Complex{b, a, a}, &strb, m} if DeepEqual(a, b) { t.Error("DeepEqual(complex different) = true, want false") } } type UnexpT struct { m map[int]int } func TestDeepEqualUnexportedMap(t *testing.T) { // Check that DeepEqual can look at unexported fields. x1 := UnexpT{map[int]int{1: 2}} x2 := UnexpT{map[int]int{1: 2}} if !DeepEqual(&x1, &x2) { t.Error("DeepEqual(x1, x2) = false, want true") } y1 := UnexpT{map[int]int{2: 3}} if DeepEqual(&x1, &y1) { t.Error("DeepEqual(x1, y1) = true, want false") } } func check2ndField(x interface{}, offs uintptr, t *testing.T) { s := ValueOf(x) f := s.Type().Field(1) if f.Offset != offs { t.Error("mismatched offsets in structure alignment:", f.Offset, offs) } } // Check that structure alignment & offsets viewed through reflect agree with those // from the compiler itself. func TestAlignment(t *testing.T) { type T1inner struct { a int } type T1 struct { T1inner f int } type T2inner struct { a, b int } type T2 struct { T2inner f int } x := T1{T1inner{2}, 17} check2ndField(x, uintptr(unsafe.Pointer(&x.f))-uintptr(unsafe.Pointer(&x)), t) x1 := T2{T2inner{2, 3}, 17} check2ndField(x1, uintptr(unsafe.Pointer(&x1.f))-uintptr(unsafe.Pointer(&x1)), t) } func Nil(a interface{}, t *testing.T) { n := ValueOf(a).Field(0) if !n.IsNil() { t.Errorf("%v should be nil", a) } } func NotNil(a interface{}, t *testing.T) { n := ValueOf(a).Field(0) if n.IsNil() { t.Errorf("value of type %v should not be nil", ValueOf(a).Type().String()) } } func TestIsNil(t *testing.T) { // These implement IsNil. // Wrap in extra struct to hide interface type. doNil := []interface{}{ struct{ x *int }{}, struct{ x interface{} }{}, struct{ x map[string]int }{}, struct{ x func() bool }{}, struct{ x chan int }{}, struct{ x []string }{}, } for _, ts := range doNil { ty := TypeOf(ts).Field(0).Type v := Zero(ty) v.IsNil() // panics if not okay to call } // Check the implementations var pi struct { x *int } Nil(pi, t) pi.x = new(int) NotNil(pi, t) var si struct { x []int } Nil(si, t) si.x = make([]int, 10) NotNil(si, t) var ci struct { x chan int } Nil(ci, t) ci.x = make(chan int) NotNil(ci, t) var mi struct { x map[int]int } Nil(mi, t) mi.x = make(map[int]int) NotNil(mi, t) var ii struct { x interface{} } Nil(ii, t) ii.x = 2 NotNil(ii, t) var fi struct { x func(t *testing.T) } Nil(fi, t) fi.x = TestIsNil NotNil(fi, t) } func TestInterfaceExtraction(t *testing.T) { var s struct { W io.Writer } s.W = os.Stdout v := Indirect(ValueOf(&s)).Field(0).Interface() if v != s.W.(interface{}) { t.Error("Interface() on interface: ", v, s.W) } } func TestNilPtrValueSub(t *testing.T) { var pi *int if pv := ValueOf(pi); pv.Elem().IsValid() { t.Error("ValueOf((*int)(nil)).Elem().IsValid()") } } func TestMap(t *testing.T) { m := map[string]int{"a": 1, "b": 2} mv := ValueOf(m) if n := mv.Len(); n != len(m) { t.Errorf("Len = %d, want %d", n, len(m)) } keys := mv.MapKeys() newmap := MakeMap(mv.Type()) for k, v := range m { // Check that returned Keys match keys in range. // These aren't required to be in the same order. seen := false for _, kv := range keys { if kv.String() == k { seen = true break } } if !seen { t.Errorf("Missing key %q", k) } // Check that value lookup is correct. vv := mv.MapIndex(ValueOf(k)) if vi := vv.Int(); vi != int64(v) { t.Errorf("Key %q: have value %d, want %d", k, vi, v) } // Copy into new map. newmap.SetMapIndex(ValueOf(k), ValueOf(v)) } vv := mv.MapIndex(ValueOf("not-present")) if vv.IsValid() { t.Errorf("Invalid key: got non-nil value %s", valueToString(vv)) } newm := newmap.Interface().(map[string]int) if len(newm) != len(m) { t.Errorf("length after copy: newm=%d, m=%d", len(newm), len(m)) } for k, v := range newm { mv, ok := m[k] if mv != v { t.Errorf("newm[%q] = %d, but m[%q] = %d, %v", k, v, k, mv, ok) } } newmap.SetMapIndex(ValueOf("a"), Value{}) v, ok := newm["a"] if ok { t.Errorf("newm[\"a\"] = %d after delete", v) } mv = ValueOf(&m).Elem() mv.Set(Zero(mv.Type())) if m != nil { t.Errorf("mv.Set(nil) failed") } } func TestNilMap(t *testing.T) { var m map[string]int mv := ValueOf(m) keys := mv.MapKeys() if len(keys) != 0 { t.Errorf(">0 keys for nil map: %v", keys) } // Check that value for missing key is zero. x := mv.MapIndex(ValueOf("hello")) if x.Kind() != Invalid { t.Errorf("m.MapIndex(\"hello\") for nil map = %v, want Invalid Value", x) } // Check big value too. var mbig map[string][10 << 20]byte x = ValueOf(mbig).MapIndex(ValueOf("hello")) if x.Kind() != Invalid { t.Errorf("mbig.MapIndex(\"hello\") for nil map = %v, want Invalid Value", x) } // Test that deletes from a nil map succeed. mv.SetMapIndex(ValueOf("hi"), Value{}) } func TestChan(t *testing.T) { for loop := 0; loop < 2; loop++ { var c chan int var cv Value // check both ways to allocate channels switch loop { case 1: c = make(chan int, 1) cv = ValueOf(c) case 0: cv = MakeChan(TypeOf(c), 1) c = cv.Interface().(chan int) } // Send cv.Send(ValueOf(2)) if i := <-c; i != 2 { t.Errorf("reflect Send 2, native recv %d", i) } // Recv c <- 3 if i, ok := cv.Recv(); i.Int() != 3 || !ok { t.Errorf("native send 3, reflect Recv %d, %t", i.Int(), ok) } // TryRecv fail val, ok := cv.TryRecv() if val.IsValid() || ok { t.Errorf("TryRecv on empty chan: %s, %t", valueToString(val), ok) } // TryRecv success c <- 4 val, ok = cv.TryRecv() if !val.IsValid() { t.Errorf("TryRecv on ready chan got nil") } else if i := val.Int(); i != 4 || !ok { t.Errorf("native send 4, TryRecv %d, %t", i, ok) } // TrySend fail c <- 100 ok = cv.TrySend(ValueOf(5)) i := <-c if ok { t.Errorf("TrySend on full chan succeeded: value %d", i) } // TrySend success ok = cv.TrySend(ValueOf(6)) if !ok { t.Errorf("TrySend on empty chan failed") select { case x := <-c: t.Errorf("TrySend failed but it did send %d", x) default: } } else { if i = <-c; i != 6 { t.Errorf("TrySend 6, recv %d", i) } } // Close c <- 123 cv.Close() if i, ok := cv.Recv(); i.Int() != 123 || !ok { t.Errorf("send 123 then close; Recv %d, %t", i.Int(), ok) } if i, ok := cv.Recv(); i.Int() != 0 || ok { t.Errorf("after close Recv %d, %t", i.Int(), ok) } } // check creation of unbuffered channel var c chan int cv := MakeChan(TypeOf(c), 0) c = cv.Interface().(chan int) if cv.TrySend(ValueOf(7)) { t.Errorf("TrySend on sync chan succeeded") } if v, ok := cv.TryRecv(); v.IsValid() || ok { t.Errorf("TryRecv on sync chan succeeded: isvalid=%v ok=%v", v.IsValid(), ok) } // len/cap cv = MakeChan(TypeOf(c), 10) c = cv.Interface().(chan int) for i := 0; i < 3; i++ { c <- i } if l, m := cv.Len(), cv.Cap(); l != len(c) || m != cap(c) { t.Errorf("Len/Cap = %d/%d want %d/%d", l, m, len(c), cap(c)) } } // caseInfo describes a single case in a select test. type caseInfo struct { desc string canSelect bool recv Value closed bool helper func() panic bool } var allselect = flag.Bool("allselect", false, "exhaustive select test") func TestSelect(t *testing.T) { selectWatch.once.Do(func() { go selectWatcher() }) var x exhaustive nch := 0 newop := func(n int, cap int) (ch, val Value) { nch++ if nch%101%2 == 1 { c := make(chan int, cap) ch = ValueOf(c) val = ValueOf(n) } else { c := make(chan string, cap) ch = ValueOf(c) val = ValueOf(fmt.Sprint(n)) } return } for n := 0; x.Next(); n++ { if testing.Short() && n >= 1000 { break } if n >= 100000 && !*allselect { break } if n%100000 == 0 && testing.Verbose() { println("TestSelect", n) } var cases []SelectCase var info []caseInfo // Ready send. if x.Maybe() { ch, val := newop(len(cases), 1) cases = append(cases, SelectCase{ Dir: SelectSend, Chan: ch, Send: val, }) info = append(info, caseInfo{desc: "ready send", canSelect: true}) } // Ready recv. if x.Maybe() { ch, val := newop(len(cases), 1) ch.Send(val) cases = append(cases, SelectCase{ Dir: SelectRecv, Chan: ch, }) info = append(info, caseInfo{desc: "ready recv", canSelect: true, recv: val}) } // Blocking send. if x.Maybe() { ch, val := newop(len(cases), 0) cases = append(cases, SelectCase{ Dir: SelectSend, Chan: ch, Send: val, }) // Let it execute? if x.Maybe() { f := func() { ch.Recv() } info = append(info, caseInfo{desc: "blocking send", helper: f}) } else { info = append(info, caseInfo{desc: "blocking send"}) } } // Blocking recv. if x.Maybe() { ch, val := newop(len(cases), 0) cases = append(cases, SelectCase{ Dir: SelectRecv, Chan: ch, }) // Let it execute? if x.Maybe() { f := func() { ch.Send(val) } info = append(info, caseInfo{desc: "blocking recv", recv: val, helper: f}) } else { info = append(info, caseInfo{desc: "blocking recv"}) } } // Zero Chan send. if x.Maybe() { // Maybe include value to send. var val Value if x.Maybe() { val = ValueOf(100) } cases = append(cases, SelectCase{ Dir: SelectSend, Send: val, }) info = append(info, caseInfo{desc: "zero Chan send"}) } // Zero Chan receive. if x.Maybe() { cases = append(cases, SelectCase{ Dir: SelectRecv, }) info = append(info, caseInfo{desc: "zero Chan recv"}) } // nil Chan send. if x.Maybe() { cases = append(cases, SelectCase{ Dir: SelectSend, Chan: ValueOf((chan int)(nil)), Send: ValueOf(101), }) info = append(info, caseInfo{desc: "nil Chan send"}) } // nil Chan recv. if x.Maybe() { cases = append(cases, SelectCase{ Dir: SelectRecv, Chan: ValueOf((chan int)(nil)), }) info = append(info, caseInfo{desc: "nil Chan recv"}) } // closed Chan send. if x.Maybe() { ch := make(chan int) close(ch) cases = append(cases, SelectCase{ Dir: SelectSend, Chan: ValueOf(ch), Send: ValueOf(101), }) info = append(info, caseInfo{desc: "closed Chan send", canSelect: true, panic: true}) } // closed Chan recv. if x.Maybe() { ch, val := newop(len(cases), 0) ch.Close() val = Zero(val.Type()) cases = append(cases, SelectCase{ Dir: SelectRecv, Chan: ch, }) info = append(info, caseInfo{desc: "closed Chan recv", canSelect: true, closed: true, recv: val}) } var helper func() // goroutine to help the select complete // Add default? Must be last case here, but will permute. // Add the default if the select would otherwise // block forever, and maybe add it anyway. numCanSelect := 0 canProceed := false canBlock := true canPanic := false helpers := []int{} for i, c := range info { if c.canSelect { canProceed = true canBlock = false numCanSelect++ if c.panic { canPanic = true } } else if c.helper != nil { canProceed = true helpers = append(helpers, i) } } if !canProceed || x.Maybe() { cases = append(cases, SelectCase{ Dir: SelectDefault, }) info = append(info, caseInfo{desc: "default", canSelect: canBlock}) numCanSelect++ } else if canBlock { // Select needs to communicate with another goroutine. cas := &info[helpers[x.Choose(len(helpers))]] helper = cas.helper cas.canSelect = true numCanSelect++ } // Permute cases and case info. // Doing too much here makes the exhaustive loop // too exhausting, so just do two swaps. for loop := 0; loop < 2; loop++ { i := x.Choose(len(cases)) j := x.Choose(len(cases)) cases[i], cases[j] = cases[j], cases[i] info[i], info[j] = info[j], info[i] } if helper != nil { // We wait before kicking off a goroutine to satisfy a blocked select. // The pause needs to be big enough to let the select block before // we run the helper, but if we lose that race once in a while it's okay: the // select will just proceed immediately. Not a big deal. // For short tests we can grow [sic] the timeout a bit without fear of taking too long pause := 10 * time.Microsecond if testing.Short() { pause = 100 * time.Microsecond } time.AfterFunc(pause, helper) } // Run select. i, recv, recvOK, panicErr := runSelect(cases, info) if panicErr != nil && !canPanic { t.Fatalf("%s\npanicked unexpectedly: %v", fmtSelect(info), panicErr) } if panicErr == nil && canPanic && numCanSelect == 1 { t.Fatalf("%s\nselected #%d incorrectly (should panic)", fmtSelect(info), i) } if panicErr != nil { continue } cas := info[i] if !cas.canSelect { recvStr := "" if recv.IsValid() { recvStr = fmt.Sprintf(", received %v, %v", recv.Interface(), recvOK) } t.Fatalf("%s\nselected #%d incorrectly%s", fmtSelect(info), i, recvStr) continue } if cas.panic { t.Fatalf("%s\nselected #%d incorrectly (case should panic)", fmtSelect(info), i) continue } if cases[i].Dir == SelectRecv { if !recv.IsValid() { t.Fatalf("%s\nselected #%d but got %v, %v, want %v, %v", fmtSelect(info), i, recv, recvOK, cas.recv.Interface(), !cas.closed) } if !cas.recv.IsValid() { t.Fatalf("%s\nselected #%d but internal error: missing recv value", fmtSelect(info), i) } if recv.Interface() != cas.recv.Interface() || recvOK != !cas.closed { if recv.Interface() == cas.recv.Interface() && recvOK == !cas.closed { t.Fatalf("%s\nselected #%d, got %#v, %v, and DeepEqual is broken on %T", fmtSelect(info), i, recv.Interface(), recvOK, recv.Interface()) } t.Fatalf("%s\nselected #%d but got %#v, %v, want %#v, %v", fmtSelect(info), i, recv.Interface(), recvOK, cas.recv.Interface(), !cas.closed) } } else { if recv.IsValid() || recvOK { t.Fatalf("%s\nselected #%d but got %v, %v, want %v, %v", fmtSelect(info), i, recv, recvOK, Value{}, false) } } } } // selectWatch and the selectWatcher are a watchdog mechanism for running Select. // If the selectWatcher notices that the select has been blocked for >1 second, it prints // an error describing the select and panics the entire test binary. var selectWatch struct { sync.Mutex once sync.Once now time.Time info []caseInfo } func selectWatcher() { for { time.Sleep(1 * time.Second) selectWatch.Lock() if selectWatch.info != nil && time.Since(selectWatch.now) > 10*time.Second { fmt.Fprintf(os.Stderr, "TestSelect:\n%s blocked indefinitely\n", fmtSelect(selectWatch.info)) panic("select stuck") } selectWatch.Unlock() } } // runSelect runs a single select test. // It returns the values returned by Select but also returns // a panic value if the Select panics. func runSelect(cases []SelectCase, info []caseInfo) (chosen int, recv Value, recvOK bool, panicErr interface{}) { defer func() { panicErr = recover() selectWatch.Lock() selectWatch.info = nil selectWatch.Unlock() }() selectWatch.Lock() selectWatch.now = time.Now() selectWatch.info = info selectWatch.Unlock() chosen, recv, recvOK = Select(cases) return } // fmtSelect formats the information about a single select test. func fmtSelect(info []caseInfo) string { var buf bytes.Buffer fmt.Fprintf(&buf, "\nselect {\n") for i, cas := range info { fmt.Fprintf(&buf, "%d: %s", i, cas.desc) if cas.recv.IsValid() { fmt.Fprintf(&buf, " val=%#v", cas.recv.Interface()) } if cas.canSelect { fmt.Fprintf(&buf, " canselect") } if cas.panic { fmt.Fprintf(&buf, " panic") } fmt.Fprintf(&buf, "\n") } fmt.Fprintf(&buf, "}") return buf.String() } type two [2]uintptr // Difficult test for function call because of // implicit padding between arguments. func dummy(b byte, c int, d byte, e two, f byte, g float32, h byte) (i byte, j int, k byte, l two, m byte, n float32, o byte) { return b, c, d, e, f, g, h } func TestFunc(t *testing.T) { ret := ValueOf(dummy).Call([]Value{ ValueOf(byte(10)), ValueOf(20), ValueOf(byte(30)), ValueOf(two{40, 50}), ValueOf(byte(60)), ValueOf(float32(70)), ValueOf(byte(80)), }) if len(ret) != 7 { t.Fatalf("Call returned %d values, want 7", len(ret)) } i := byte(ret[0].Uint()) j := int(ret[1].Int()) k := byte(ret[2].Uint()) l := ret[3].Interface().(two) m := byte(ret[4].Uint()) n := float32(ret[5].Float()) o := byte(ret[6].Uint()) if i != 10 || j != 20 || k != 30 || l != (two{40, 50}) || m != 60 || n != 70 || o != 80 { t.Errorf("Call returned %d, %d, %d, %v, %d, %g, %d; want 10, 20, 30, [40, 50], 60, 70, 80", i, j, k, l, m, n, o) } } type emptyStruct struct{} type nonEmptyStruct struct { member int } func returnEmpty() emptyStruct { return emptyStruct{} } func takesEmpty(e emptyStruct) { } func returnNonEmpty(i int) nonEmptyStruct { return nonEmptyStruct{member: i} } func takesNonEmpty(n nonEmptyStruct) int { return n.member } func TestCallWithStruct(t *testing.T) { r := ValueOf(returnEmpty).Call(nil) if len(r) != 1 || r[0].Type() != TypeOf(emptyStruct{}) { t.Errorf("returning empty struct returned %#v instead", r) } r = ValueOf(takesEmpty).Call([]Value{ValueOf(emptyStruct{})}) if len(r) != 0 { t.Errorf("takesEmpty returned values: %#v", r) } r = ValueOf(returnNonEmpty).Call([]Value{ValueOf(42)}) if len(r) != 1 || r[0].Type() != TypeOf(nonEmptyStruct{}) || r[0].Field(0).Int() != 42 { t.Errorf("returnNonEmpty returned %#v", r) } r = ValueOf(takesNonEmpty).Call([]Value{ValueOf(nonEmptyStruct{member: 42})}) if len(r) != 1 || r[0].Type() != TypeOf(1) || r[0].Int() != 42 { t.Errorf("takesNonEmpty returned %#v", r) } } func BenchmarkCall(b *testing.B) { fv := ValueOf(func(a, b string) {}) b.ReportAllocs() b.RunParallel(func(pb *testing.PB) { args := []Value{ValueOf("a"), ValueOf("b")} for pb.Next() { fv.Call(args) } }) } func TestMakeFunc(t *testing.T) { f := dummy fv := MakeFunc(TypeOf(f), func(in []Value) []Value { return in }) ValueOf(&f).Elem().Set(fv) // Call g with small arguments so that there is // something predictable (and different from the // correct results) in those positions on the stack. g := dummy g(1, 2, 3, two{4, 5}, 6, 7, 8) // Call constructed function f. i, j, k, l, m, n, o := f(10, 20, 30, two{40, 50}, 60, 70, 80) if i != 10 || j != 20 || k != 30 || l != (two{40, 50}) || m != 60 || n != 70 || o != 80 { t.Errorf("Call returned %d, %d, %d, %v, %d, %g, %d; want 10, 20, 30, [40, 50], 60, 70, 80", i, j, k, l, m, n, o) } } func TestMakeFuncInterface(t *testing.T) { fn := func(i int) int { return i } incr := func(in []Value) []Value { return []Value{ValueOf(int(in[0].Int() + 1))} } fv := MakeFunc(TypeOf(fn), incr) ValueOf(&fn).Elem().Set(fv) if r := fn(2); r != 3 { t.Errorf("Call returned %d, want 3", r) } if r := fv.Call([]Value{ValueOf(14)})[0].Int(); r != 15 { t.Errorf("Call returned %d, want 15", r) } if r := fv.Interface().(func(int) int)(26); r != 27 { t.Errorf("Call returned %d, want 27", r) } } func TestMakeFuncVariadic(t *testing.T) { // Test that variadic arguments are packed into a slice and passed as last arg fn := func(_ int, is ...int) []int { return nil } fv := MakeFunc(TypeOf(fn), func(in []Value) []Value { return in[1:2] }) ValueOf(&fn).Elem().Set(fv) r := fn(1, 2, 3) if r[0] != 2 || r[1] != 3 { t.Errorf("Call returned [%v, %v]; want 2, 3", r[0], r[1]) } r = fn(1, []int{2, 3}...) if r[0] != 2 || r[1] != 3 { t.Errorf("Call returned [%v, %v]; want 2, 3", r[0], r[1]) } r = fv.Call([]Value{ValueOf(1), ValueOf(2), ValueOf(3)})[0].Interface().([]int) if r[0] != 2 || r[1] != 3 { t.Errorf("Call returned [%v, %v]; want 2, 3", r[0], r[1]) } r = fv.CallSlice([]Value{ValueOf(1), ValueOf([]int{2, 3})})[0].Interface().([]int) if r[0] != 2 || r[1] != 3 { t.Errorf("Call returned [%v, %v]; want 2, 3", r[0], r[1]) } f := fv.Interface().(func(int, ...int) []int) r = f(1, 2, 3) if r[0] != 2 || r[1] != 3 { t.Errorf("Call returned [%v, %v]; want 2, 3", r[0], r[1]) } r = f(1, []int{2, 3}...) if r[0] != 2 || r[1] != 3 { t.Errorf("Call returned [%v, %v]; want 2, 3", r[0], r[1]) } } type Point struct { x, y int } // This will be index 0. func (p Point) AnotherMethod(scale int) int { return -1 } // This will be index 1. func (p Point) Dist(scale int) int { //println("Point.Dist", p.x, p.y, scale) return p.x*p.x*scale + p.y*p.y*scale } // This will be index 2. func (p Point) GCMethod(k int) int { runtime.GC() return k + p.x } // This will be index 3. func (p Point) TotalDist(points ...Point) int { tot := 0 for _, q := range points { dx := q.x - p.x dy := q.y - p.y tot += dx*dx + dy*dy // Should call Sqrt, but it's just a test. } return tot } func TestMethod(t *testing.T) { // Non-curried method of type. p := Point{3, 4} i := TypeOf(p).Method(1).Func.Call([]Value{ValueOf(p), ValueOf(10)})[0].Int() if i != 250 { t.Errorf("Type Method returned %d; want 250", i) } m, ok := TypeOf(p).MethodByName("Dist") if !ok { t.Fatalf("method by name failed") } i = m.Func.Call([]Value{ValueOf(p), ValueOf(11)})[0].Int() if i != 275 { t.Errorf("Type MethodByName returned %d; want 275", i) } i = TypeOf(&p).Method(1).Func.Call([]Value{ValueOf(&p), ValueOf(12)})[0].Int() if i != 300 { t.Errorf("Pointer Type Method returned %d; want 300", i) } m, ok = TypeOf(&p).MethodByName("Dist") if !ok { t.Fatalf("ptr method by name failed") } i = m.Func.Call([]Value{ValueOf(&p), ValueOf(13)})[0].Int() if i != 325 { t.Errorf("Pointer Type MethodByName returned %d; want 325", i) } // Curried method of value. tfunc := TypeOf((func(int) int)(nil)) v := ValueOf(p).Method(1) if tt := v.Type(); tt != tfunc { t.Errorf("Value Method Type is %s; want %s", tt, tfunc) } i = v.Call([]Value{ValueOf(14)})[0].Int() if i != 350 { t.Errorf("Value Method returned %d; want 350", i) } v = ValueOf(p).MethodByName("Dist") if tt := v.Type(); tt != tfunc { t.Errorf("Value MethodByName Type is %s; want %s", tt, tfunc) } i = v.Call([]Value{ValueOf(15)})[0].Int() if i != 375 { t.Errorf("Value MethodByName returned %d; want 375", i) } // Curried method of pointer. v = ValueOf(&p).Method(1) if tt := v.Type(); tt != tfunc { t.Errorf("Pointer Value Method Type is %s; want %s", tt, tfunc) } i = v.Call([]Value{ValueOf(16)})[0].Int() if i != 400 { t.Errorf("Pointer Value Method returned %d; want 400", i) } v = ValueOf(&p).MethodByName("Dist") if tt := v.Type(); tt != tfunc { t.Errorf("Pointer Value MethodByName Type is %s; want %s", tt, tfunc) } i = v.Call([]Value{ValueOf(17)})[0].Int() if i != 425 { t.Errorf("Pointer Value MethodByName returned %d; want 425", i) } // Curried method of interface value. // Have to wrap interface value in a struct to get at it. // Passing it to ValueOf directly would // access the underlying Point, not the interface. var x interface { Dist(int) int } = p pv := ValueOf(&x).Elem() v = pv.Method(0) if tt := v.Type(); tt != tfunc { t.Errorf("Interface Method Type is %s; want %s", tt, tfunc) } i = v.Call([]Value{ValueOf(18)})[0].Int() if i != 450 { t.Errorf("Interface Method returned %d; want 450", i) } v = pv.MethodByName("Dist") if tt := v.Type(); tt != tfunc { t.Errorf("Interface MethodByName Type is %s; want %s", tt, tfunc) } i = v.Call([]Value{ValueOf(19)})[0].Int() if i != 475 { t.Errorf("Interface MethodByName returned %d; want 475", i) } } func TestMethodValue(t *testing.T) { p := Point{3, 4} var i int64 // Curried method of value. tfunc := TypeOf((func(int) int)(nil)) v := ValueOf(p).Method(1) if tt := v.Type(); tt != tfunc { t.Errorf("Value Method Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(10)})[0].Int() if i != 250 { t.Errorf("Value Method returned %d; want 250", i) } v = ValueOf(p).MethodByName("Dist") if tt := v.Type(); tt != tfunc { t.Errorf("Value MethodByName Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(11)})[0].Int() if i != 275 { t.Errorf("Value MethodByName returned %d; want 275", i) } // Curried method of pointer. v = ValueOf(&p).Method(1) if tt := v.Type(); tt != tfunc { t.Errorf("Pointer Value Method Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(12)})[0].Int() if i != 300 { t.Errorf("Pointer Value Method returned %d; want 300", i) } v = ValueOf(&p).MethodByName("Dist") if tt := v.Type(); tt != tfunc { t.Errorf("Pointer Value MethodByName Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(13)})[0].Int() if i != 325 { t.Errorf("Pointer Value MethodByName returned %d; want 325", i) } // Curried method of pointer to pointer. pp := &p v = ValueOf(&pp).Elem().Method(1) if tt := v.Type(); tt != tfunc { t.Errorf("Pointer Pointer Value Method Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(14)})[0].Int() if i != 350 { t.Errorf("Pointer Pointer Value Method returned %d; want 350", i) } v = ValueOf(&pp).Elem().MethodByName("Dist") if tt := v.Type(); tt != tfunc { t.Errorf("Pointer Pointer Value MethodByName Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(15)})[0].Int() if i != 375 { t.Errorf("Pointer Pointer Value MethodByName returned %d; want 375", i) } // Curried method of interface value. // Have to wrap interface value in a struct to get at it. // Passing it to ValueOf directly would // access the underlying Point, not the interface. var s = struct { X interface { Dist(int) int } }{p} pv := ValueOf(s).Field(0) v = pv.Method(0) if tt := v.Type(); tt != tfunc { t.Errorf("Interface Method Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(16)})[0].Int() if i != 400 { t.Errorf("Interface Method returned %d; want 400", i) } v = pv.MethodByName("Dist") if tt := v.Type(); tt != tfunc { t.Errorf("Interface MethodByName Type is %s; want %s", tt, tfunc) } i = ValueOf(v.Interface()).Call([]Value{ValueOf(17)})[0].Int() if i != 425 { t.Errorf("Interface MethodByName returned %d; want 425", i) } } func TestVariadicMethodValue(t *testing.T) { p := Point{3, 4} points := []Point{{20, 21}, {22, 23}, {24, 25}} want := int64(p.TotalDist(points[0], points[1], points[2])) // Curried method of value. tfunc := TypeOf((func(...Point) int)(nil)) v := ValueOf(p).Method(3) if tt := v.Type(); tt != tfunc { t.Errorf("Variadic Method Type is %s; want %s", tt, tfunc) } i := ValueOf(v.Interface()).Call([]Value{ValueOf(points[0]), ValueOf(points[1]), ValueOf(points[2])})[0].Int() if i != want { t.Errorf("Variadic Method returned %d; want %d", i, want) } i = ValueOf(v.Interface()).CallSlice([]Value{ValueOf(points)})[0].Int() if i != want { t.Errorf("Variadic Method CallSlice returned %d; want %d", i, want) } f := v.Interface().(func(...Point) int) i = int64(f(points[0], points[1], points[2])) if i != want { t.Errorf("Variadic Method Interface returned %d; want %d", i, want) } i = int64(f(points...)) if i != want { t.Errorf("Variadic Method Interface Slice returned %d; want %d", i, want) } } // Reflect version of $GOROOT/test/method5.go // Concrete types implementing M method. // Smaller than a word, word-sized, larger than a word. // Value and pointer receivers. type Tinter interface { M(int, byte) (byte, int) } type Tsmallv byte func (v Tsmallv) M(x int, b byte) (byte, int) { return b, x + int(v) } type Tsmallp byte func (p *Tsmallp) M(x int, b byte) (byte, int) { return b, x + int(*p) } type Twordv uintptr func (v Twordv) M(x int, b byte) (byte, int) { return b, x + int(v) } type Twordp uintptr func (p *Twordp) M(x int, b byte) (byte, int) { return b, x + int(*p) } type Tbigv [2]uintptr func (v Tbigv) M(x int, b byte) (byte, int) { return b, x + int(v[0]) + int(v[1]) } type Tbigp [2]uintptr func (p *Tbigp) M(x int, b byte) (byte, int) { return b, x + int(p[0]) + int(p[1]) } // Again, with an unexported method. type tsmallv byte func (v tsmallv) m(x int, b byte) (byte, int) { return b, x + int(v) } type tsmallp byte func (p *tsmallp) m(x int, b byte) (byte, int) { return b, x + int(*p) } type twordv uintptr func (v twordv) m(x int, b byte) (byte, int) { return b, x + int(v) } type twordp uintptr func (p *twordp) m(x int, b byte) (byte, int) { return b, x + int(*p) } type tbigv [2]uintptr func (v tbigv) m(x int, b byte) (byte, int) { return b, x + int(v[0]) + int(v[1]) } type tbigp [2]uintptr func (p *tbigp) m(x int, b byte) (byte, int) { return b, x + int(p[0]) + int(p[1]) } type tinter interface { m(int, byte) (byte, int) } // Embedding via pointer. type Tm1 struct { Tm2 } type Tm2 struct { *Tm3 } type Tm3 struct { *Tm4 } type Tm4 struct { } func (t4 Tm4) M(x int, b byte) (byte, int) { return b, x + 40 } func TestMethod5(t *testing.T) { CheckF := func(name string, f func(int, byte) (byte, int), inc int) { b, x := f(1000, 99) if b != 99 || x != 1000+inc { t.Errorf("%s(1000, 99) = %v, %v, want 99, %v", name, b, x, 1000+inc) } } CheckV := func(name string, i Value, inc int) { bx := i.Method(0).Call([]Value{ValueOf(1000), ValueOf(byte(99))}) b := bx[0].Interface() x := bx[1].Interface() if b != byte(99) || x != 1000+inc { t.Errorf("direct %s.M(1000, 99) = %v, %v, want 99, %v", name, b, x, 1000+inc) } CheckF(name+".M", i.Method(0).Interface().(func(int, byte) (byte, int)), inc) } var TinterType = TypeOf(new(Tinter)).Elem() var tinterType = TypeOf(new(tinter)).Elem() CheckI := func(name string, i interface{}, inc int) { v := ValueOf(i) CheckV(name, v, inc) CheckV("(i="+name+")", v.Convert(TinterType), inc) } sv := Tsmallv(1) CheckI("sv", sv, 1) CheckI("&sv", &sv, 1) sp := Tsmallp(2) CheckI("&sp", &sp, 2) wv := Twordv(3) CheckI("wv", wv, 3) CheckI("&wv", &wv, 3) wp := Twordp(4) CheckI("&wp", &wp, 4) bv := Tbigv([2]uintptr{5, 6}) CheckI("bv", bv, 11) CheckI("&bv", &bv, 11) bp := Tbigp([2]uintptr{7, 8}) CheckI("&bp", &bp, 15) t4 := Tm4{} t3 := Tm3{&t4} t2 := Tm2{&t3} t1 := Tm1{t2} CheckI("t4", t4, 40) CheckI("&t4", &t4, 40) CheckI("t3", t3, 40) CheckI("&t3", &t3, 40) CheckI("t2", t2, 40) CheckI("&t2", &t2, 40) CheckI("t1", t1, 40) CheckI("&t1", &t1, 40) methodShouldPanic := func(name string, i interface{}) { v := ValueOf(i) m := v.Method(0) shouldPanic(func() { m.Call([]Value{ValueOf(1000), ValueOf(byte(99))}) }) shouldPanic(func() { m.Interface() }) v = v.Convert(tinterType) m = v.Method(0) shouldPanic(func() { m.Call([]Value{ValueOf(1000), ValueOf(byte(99))}) }) shouldPanic(func() { m.Interface() }) } _sv := tsmallv(1) methodShouldPanic("_sv", _sv) methodShouldPanic("&_sv", &_sv) _sp := tsmallp(2) methodShouldPanic("&_sp", &_sp) _wv := twordv(3) methodShouldPanic("_wv", _wv) methodShouldPanic("&_wv", &_wv) _wp := twordp(4) methodShouldPanic("&_wp", &_wp) _bv := tbigv([2]uintptr{5, 6}) methodShouldPanic("_bv", _bv) methodShouldPanic("&_bv", &_bv) _bp := tbigp([2]uintptr{7, 8}) methodShouldPanic("&_bp", &_bp) var tnil Tinter vnil := ValueOf(&tnil).Elem() shouldPanic(func() { vnil.Method(0) }) } func TestInterfaceSet(t *testing.T) { p := &Point{3, 4} var s struct { I interface{} P interface { Dist(int) int } } sv := ValueOf(&s).Elem() sv.Field(0).Set(ValueOf(p)) if q := s.I.(*Point); q != p { t.Errorf("i: have %p want %p", q, p) } pv := sv.Field(1) pv.Set(ValueOf(p)) if q := s.P.(*Point); q != p { t.Errorf("i: have %p want %p", q, p) } i := pv.Method(0).Call([]Value{ValueOf(10)})[0].Int() if i != 250 { t.Errorf("Interface Method returned %d; want 250", i) } } type T1 struct { a string int } func TestAnonymousFields(t *testing.T) { var field StructField var ok bool var t1 T1 type1 := TypeOf(t1) if field, ok = type1.FieldByName("int"); !ok { t.Fatal("no field 'int'") } if field.Index[0] != 1 { t.Error("field index should be 1; is", field.Index) } } type FTest struct { s interface{} name string index []int value int } type D1 struct { d int } type D2 struct { d int } type S0 struct { A, B, C int D1 D2 } type S1 struct { B int S0 } type S2 struct { A int *S1 } type S1x struct { S1 } type S1y struct { S1 } type S3 struct { S1x S2 D, E int *S1y } type S4 struct { *S4 A int } // The X in S6 and S7 annihilate, but they also block the X in S8.S9. type S5 struct { S6 S7 S8 } type S6 struct { X int } type S7 S6 type S8 struct { S9 } type S9 struct { X int Y int } // The X in S11.S6 and S12.S6 annihilate, but they also block the X in S13.S8.S9. type S10 struct { S11 S12 S13 } type S11 struct { S6 } type S12 struct { S6 } type S13 struct { S8 } // The X in S15.S11.S1 and S16.S11.S1 annihilate. type S14 struct { S15 S16 } type S15 struct { S11 } type S16 struct { S11 } var fieldTests = []FTest{ {struct{}{}, "", nil, 0}, {struct{}{}, "Foo", nil, 0}, {S0{A: 'a'}, "A", []int{0}, 'a'}, {S0{}, "D", nil, 0}, {S1{S0: S0{A: 'a'}}, "A", []int{1, 0}, 'a'}, {S1{B: 'b'}, "B", []int{0}, 'b'}, {S1{}, "S0", []int{1}, 0}, {S1{S0: S0{C: 'c'}}, "C", []int{1, 2}, 'c'}, {S2{A: 'a'}, "A", []int{0}, 'a'}, {S2{}, "S1", []int{1}, 0}, {S2{S1: &S1{B: 'b'}}, "B", []int{1, 0}, 'b'}, {S2{S1: &S1{S0: S0{C: 'c'}}}, "C", []int{1, 1, 2}, 'c'}, {S2{}, "D", nil, 0}, {S3{}, "S1", nil, 0}, {S3{S2: S2{A: 'a'}}, "A", []int{1, 0}, 'a'}, {S3{}, "B", nil, 0}, {S3{D: 'd'}, "D", []int{2}, 0}, {S3{E: 'e'}, "E", []int{3}, 'e'}, {S4{A: 'a'}, "A", []int{1}, 'a'}, {S4{}, "B", nil, 0}, {S5{}, "X", nil, 0}, {S5{}, "Y", []int{2, 0, 1}, 0}, {S10{}, "X", nil, 0}, {S10{}, "Y", []int{2, 0, 0, 1}, 0}, {S14{}, "X", nil, 0}, } func TestFieldByIndex(t *testing.T) { for _, test := range fieldTests { s := TypeOf(test.s) f := s.FieldByIndex(test.index) if f.Name != "" { if test.index != nil { if f.Name != test.name { t.Errorf("%s.%s found; want %s", s.Name(), f.Name, test.name) } } else { t.Errorf("%s.%s found", s.Name(), f.Name) } } else if len(test.index) > 0 { t.Errorf("%s.%s not found", s.Name(), test.name) } if test.value != 0 { v := ValueOf(test.s).FieldByIndex(test.index) if v.IsValid() { if x, ok := v.Interface().(int); ok { if x != test.value { t.Errorf("%s%v is %d; want %d", s.Name(), test.index, x, test.value) } } else { t.Errorf("%s%v value not an int", s.Name(), test.index) } } else { t.Errorf("%s%v value not found", s.Name(), test.index) } } } } func TestFieldByName(t *testing.T) { for _, test := range fieldTests { s := TypeOf(test.s) f, found := s.FieldByName(test.name) if found { if test.index != nil { // Verify field depth and index. if len(f.Index) != len(test.index) { t.Errorf("%s.%s depth %d; want %d: %v vs %v", s.Name(), test.name, len(f.Index), len(test.index), f.Index, test.index) } else { for i, x := range f.Index { if x != test.index[i] { t.Errorf("%s.%s.Index[%d] is %d; want %d", s.Name(), test.name, i, x, test.index[i]) } } } } else { t.Errorf("%s.%s found", s.Name(), f.Name) } } else if len(test.index) > 0 { t.Errorf("%s.%s not found", s.Name(), test.name) } if test.value != 0 { v := ValueOf(test.s).FieldByName(test.name) if v.IsValid() { if x, ok := v.Interface().(int); ok { if x != test.value { t.Errorf("%s.%s is %d; want %d", s.Name(), test.name, x, test.value) } } else { t.Errorf("%s.%s value not an int", s.Name(), test.name) } } else { t.Errorf("%s.%s value not found", s.Name(), test.name) } } } } func TestImportPath(t *testing.T) { tests := []struct { t Type path string }{ {TypeOf(&base64.Encoding{}).Elem(), "encoding/base64"}, {TypeOf(int(0)), ""}, {TypeOf(int8(0)), ""}, {TypeOf(int16(0)), ""}, {TypeOf(int32(0)), ""}, {TypeOf(int64(0)), ""}, {TypeOf(uint(0)), ""}, {TypeOf(uint8(0)), ""}, {TypeOf(uint16(0)), ""}, {TypeOf(uint32(0)), ""}, {TypeOf(uint64(0)), ""}, {TypeOf(uintptr(0)), ""}, {TypeOf(float32(0)), ""}, {TypeOf(float64(0)), ""}, {TypeOf(complex64(0)), ""}, {TypeOf(complex128(0)), ""}, {TypeOf(byte(0)), ""}, {TypeOf(rune(0)), ""}, {TypeOf([]byte(nil)), ""}, {TypeOf([]rune(nil)), ""}, {TypeOf(string("")), ""}, {TypeOf((*interface{})(nil)).Elem(), ""}, {TypeOf((*byte)(nil)), ""}, {TypeOf((*rune)(nil)), ""}, {TypeOf((*int64)(nil)), ""}, {TypeOf(map[string]int{}), ""}, {TypeOf((*error)(nil)).Elem(), ""}, } for _, test := range tests { if path := test.t.PkgPath(); path != test.path { t.Errorf("%v.PkgPath() = %q, want %q", test.t, path, test.path) } } } func TestVariadicType(t *testing.T) { // Test example from Type documentation. var f func(x int, y ...float64) typ := TypeOf(f) if typ.NumIn() == 2 && typ.In(0) == TypeOf(int(0)) { sl := typ.In(1) if sl.Kind() == Slice { if sl.Elem() == TypeOf(0.0) { // ok return } } } // Failed t.Errorf("want NumIn() = 2, In(0) = int, In(1) = []float64") s := fmt.Sprintf("have NumIn() = %d", typ.NumIn()) for i := 0; i < typ.NumIn(); i++ { s += fmt.Sprintf(", In(%d) = %s", i, typ.In(i)) } t.Error(s) } type inner struct { x int } type outer struct { y int inner } func (*inner) m() {} func (*outer) m() {} func TestNestedMethods(t *testing.T) { typ := TypeOf((*outer)(nil)) if typ.NumMethod() != 1 || typ.Method(0).Func.Pointer() != ValueOf((*outer).m).Pointer() { t.Errorf("Wrong method table for outer: (m=%p)", (*outer).m) for i := 0; i < typ.NumMethod(); i++ { m := typ.Method(i) t.Errorf("\t%d: %s %#x\n", i, m.Name, m.Func.Pointer()) } } } type InnerInt struct { X int } type OuterInt struct { Y int InnerInt } func (i *InnerInt) M() int { return i.X } func TestEmbeddedMethods(t *testing.T) { typ := TypeOf((*OuterInt)(nil)) if typ.NumMethod() != 1 || typ.Method(0).Func.Pointer() != ValueOf((*OuterInt).M).Pointer() { t.Errorf("Wrong method table for OuterInt: (m=%p)", (*OuterInt).M) for i := 0; i < typ.NumMethod(); i++ { m := typ.Method(i) t.Errorf("\t%d: %s %#x\n", i, m.Name, m.Func.Pointer()) } } i := &InnerInt{3} if v := ValueOf(i).Method(0).Call(nil)[0].Int(); v != 3 { t.Errorf("i.M() = %d, want 3", v) } o := &OuterInt{1, InnerInt{2}} if v := ValueOf(o).Method(0).Call(nil)[0].Int(); v != 2 { t.Errorf("i.M() = %d, want 2", v) } f := (*OuterInt).M if v := f(o); v != 2 { t.Errorf("f(o) = %d, want 2", v) } } func TestPtrTo(t *testing.T) { var i int typ := TypeOf(i) for i = 0; i < 100; i++ { typ = PtrTo(typ) } for i = 0; i < 100; i++ { typ = typ.Elem() } if typ != TypeOf(i) { t.Errorf("after 100 PtrTo and Elem, have %s, want %s", typ, TypeOf(i)) } } func TestPtrToGC(t *testing.T) { type T *uintptr tt := TypeOf(T(nil)) pt := PtrTo(tt) const n = 100 var x []interface{} for i := 0; i < n; i++ { v := New(pt) p := new(*uintptr) *p = new(uintptr) **p = uintptr(i) v.Elem().Set(ValueOf(p).Convert(pt)) x = append(x, v.Interface()) } runtime.GC() for i, xi := range x { k := ValueOf(xi).Elem().Elem().Elem().Interface().(uintptr) if k != uintptr(i) { t.Errorf("lost x[%d] = %d, want %d", i, k, i) } } } func TestAddr(t *testing.T) { var p struct { X, Y int } v := ValueOf(&p) v = v.Elem() v = v.Addr() v = v.Elem() v = v.Field(0) v.SetInt(2) if p.X != 2 { t.Errorf("Addr.Elem.Set failed to set value") } // Again but take address of the ValueOf value. // Exercises generation of PtrTypes not present in the binary. q := &p v = ValueOf(&q).Elem() v = v.Addr() v = v.Elem() v = v.Elem() v = v.Addr() v = v.Elem() v = v.Field(0) v.SetInt(3) if p.X != 3 { t.Errorf("Addr.Elem.Set failed to set value") } // Starting without pointer we should get changed value // in interface. qq := p v = ValueOf(&qq).Elem() v0 := v v = v.Addr() v = v.Elem() v = v.Field(0) v.SetInt(4) if p.X != 3 { // should be unchanged from last time t.Errorf("somehow value Set changed original p") } p = v0.Interface().(struct { X, Y int }) if p.X != 4 { t.Errorf("Addr.Elem.Set valued to set value in top value") } // Verify that taking the address of a type gives us a pointer // which we can convert back using the usual interface // notation. var s struct { B *bool } ps := ValueOf(&s).Elem().Field(0).Addr().Interface() *(ps.(**bool)) = new(bool) if s.B == nil { t.Errorf("Addr.Interface direct assignment failed") } } func noAlloc(t *testing.T, n int, f func(int)) { if testing.Short() { t.Skip("skipping malloc count in short mode") } if runtime.GOMAXPROCS(0) > 1 { t.Skip("skipping; GOMAXPROCS>1") } i := -1 allocs := testing.AllocsPerRun(n, func() { f(i) i++ }) if allocs > 0 { t.Errorf("%d iterations: got %v mallocs, want 0", n, allocs) } } func TestAllocations(t *testing.T) { noAlloc(t, 100, func(j int) { var i interface{} var v Value // We can uncomment this when compiler escape analysis // is good enough to see that the integer assigned to i // does not escape and therefore need not be allocated. // // i = 42 + j // v = ValueOf(i) // if int(v.Int()) != 42+j { // panic("wrong int") // } i = func(j int) int { return j } v = ValueOf(i) if v.Interface().(func(int) int)(j) != j { panic("wrong result") } }) } func TestSmallNegativeInt(t *testing.T) { i := int16(-1) v := ValueOf(i) if v.Int() != -1 { t.Errorf("int16(-1).Int() returned %v", v.Int()) } } func TestIndex(t *testing.T) { xs := []byte{1, 2, 3, 4, 5, 6, 7, 8} v := ValueOf(xs).Index(3).Interface().(byte) if v != xs[3] { t.Errorf("xs.Index(3) = %v; expected %v", v, xs[3]) } xa := [8]byte{10, 20, 30, 40, 50, 60, 70, 80} v = ValueOf(xa).Index(2).Interface().(byte) if v != xa[2] { t.Errorf("xa.Index(2) = %v; expected %v", v, xa[2]) } s := "0123456789" v = ValueOf(s).Index(3).Interface().(byte) if v != s[3] { t.Errorf("s.Index(3) = %v; expected %v", v, s[3]) } } func TestSlice(t *testing.T) { xs := []int{1, 2, 3, 4, 5, 6, 7, 8} v := ValueOf(xs).Slice(3, 5).Interface().([]int) if len(v) != 2 { t.Errorf("len(xs.Slice(3, 5)) = %d", len(v)) } if cap(v) != 5 { t.Errorf("cap(xs.Slice(3, 5)) = %d", cap(v)) } if !DeepEqual(v[0:5], xs[3:]) { t.Errorf("xs.Slice(3, 5)[0:5] = %v", v[0:5]) } xa := [8]int{10, 20, 30, 40, 50, 60, 70, 80} v = ValueOf(&xa).Elem().Slice(2, 5).Interface().([]int) if len(v) != 3 { t.Errorf("len(xa.Slice(2, 5)) = %d", len(v)) } if cap(v) != 6 { t.Errorf("cap(xa.Slice(2, 5)) = %d", cap(v)) } if !DeepEqual(v[0:6], xa[2:]) { t.Errorf("xs.Slice(2, 5)[0:6] = %v", v[0:6]) } s := "0123456789" vs := ValueOf(s).Slice(3, 5).Interface().(string) if vs != s[3:5] { t.Errorf("s.Slice(3, 5) = %q; expected %q", vs, s[3:5]) } rv := ValueOf(&xs).Elem() rv = rv.Slice(3, 4) ptr2 := rv.Pointer() rv = rv.Slice(5, 5) ptr3 := rv.Pointer() if ptr3 != ptr2 { t.Errorf("xs.Slice(3,4).Slice3(5,5).Pointer() = %#x, want %#x", ptr3, ptr2) } } func TestSlice3(t *testing.T) { xs := []int{1, 2, 3, 4, 5, 6, 7, 8} v := ValueOf(xs).Slice3(3, 5, 7).Interface().([]int) if len(v) != 2 { t.Errorf("len(xs.Slice3(3, 5, 7)) = %d", len(v)) } if cap(v) != 4 { t.Errorf("cap(xs.Slice3(3, 5, 7)) = %d", cap(v)) } if !DeepEqual(v[0:4], xs[3:7:7]) { t.Errorf("xs.Slice3(3, 5, 7)[0:4] = %v", v[0:4]) } rv := ValueOf(&xs).Elem() shouldPanic(func() { rv.Slice3(1, 2, 1) }) shouldPanic(func() { rv.Slice3(1, 1, 11) }) shouldPanic(func() { rv.Slice3(2, 2, 1) }) xa := [8]int{10, 20, 30, 40, 50, 60, 70, 80} v = ValueOf(&xa).Elem().Slice3(2, 5, 6).Interface().([]int) if len(v) != 3 { t.Errorf("len(xa.Slice(2, 5, 6)) = %d", len(v)) } if cap(v) != 4 { t.Errorf("cap(xa.Slice(2, 5, 6)) = %d", cap(v)) } if !DeepEqual(v[0:4], xa[2:6:6]) { t.Errorf("xs.Slice(2, 5, 6)[0:4] = %v", v[0:4]) } rv = ValueOf(&xa).Elem() shouldPanic(func() { rv.Slice3(1, 2, 1) }) shouldPanic(func() { rv.Slice3(1, 1, 11) }) shouldPanic(func() { rv.Slice3(2, 2, 1) }) s := "hello world" rv = ValueOf(&s).Elem() shouldPanic(func() { rv.Slice3(1, 2, 3) }) rv = ValueOf(&xs).Elem() rv = rv.Slice3(3, 5, 7) ptr2 := rv.Pointer() rv = rv.Slice3(4, 4, 4) ptr3 := rv.Pointer() if ptr3 != ptr2 { t.Errorf("xs.Slice3(3,5,7).Slice3(4,4,4).Pointer() = %#x, want %#x", ptr3, ptr2) } } func TestSetLenCap(t *testing.T) { xs := []int{1, 2, 3, 4, 5, 6, 7, 8} xa := [8]int{10, 20, 30, 40, 50, 60, 70, 80} vs := ValueOf(&xs).Elem() shouldPanic(func() { vs.SetLen(10) }) shouldPanic(func() { vs.SetCap(10) }) shouldPanic(func() { vs.SetLen(-1) }) shouldPanic(func() { vs.SetCap(-1) }) shouldPanic(func() { vs.SetCap(6) }) // smaller than len vs.SetLen(5) if len(xs) != 5 || cap(xs) != 8 { t.Errorf("after SetLen(5), len, cap = %d, %d, want 5, 8", len(xs), cap(xs)) } vs.SetCap(6) if len(xs) != 5 || cap(xs) != 6 { t.Errorf("after SetCap(6), len, cap = %d, %d, want 5, 6", len(xs), cap(xs)) } vs.SetCap(5) if len(xs) != 5 || cap(xs) != 5 { t.Errorf("after SetCap(5), len, cap = %d, %d, want 5, 5", len(xs), cap(xs)) } shouldPanic(func() { vs.SetCap(4) }) // smaller than len shouldPanic(func() { vs.SetLen(6) }) // bigger than cap va := ValueOf(&xa).Elem() shouldPanic(func() { va.SetLen(8) }) shouldPanic(func() { va.SetCap(8) }) } func TestVariadic(t *testing.T) { var b bytes.Buffer V := ValueOf b.Reset() V(fmt.Fprintf).Call([]Value{V(&b), V("%s, %d world"), V("hello"), V(42)}) if b.String() != "hello, 42 world" { t.Errorf("after Fprintf Call: %q != %q", b.String(), "hello 42 world") } b.Reset() V(fmt.Fprintf).CallSlice([]Value{V(&b), V("%s, %d world"), V([]interface{}{"hello", 42})}) if b.String() != "hello, 42 world" { t.Errorf("after Fprintf CallSlice: %q != %q", b.String(), "hello 42 world") } } func TestFuncArg(t *testing.T) { f1 := func(i int, f func(int) int) int { return f(i) } f2 := func(i int) int { return i + 1 } r := ValueOf(f1).Call([]Value{ValueOf(100), ValueOf(f2)}) if r[0].Int() != 101 { t.Errorf("function returned %d, want 101", r[0].Int()) } } func TestStructArg(t *testing.T) { type padded struct { B string C int32 } var ( gotA padded gotB uint32 wantA = padded{"3", 4} wantB = uint32(5) ) f := func(a padded, b uint32) { gotA, gotB = a, b } ValueOf(f).Call([]Value{ValueOf(wantA), ValueOf(wantB)}) if gotA != wantA || gotB != wantB { t.Errorf("function called with (%v, %v), want (%v, %v)", gotA, gotB, wantA, wantB) } } var tagGetTests = []struct { Tag StructTag Key string Value string }{ {`protobuf:"PB(1,2)"`, `protobuf`, `PB(1,2)`}, {`protobuf:"PB(1,2)"`, `foo`, ``}, {`protobuf:"PB(1,2)"`, `rotobuf`, ``}, {`protobuf:"PB(1,2)" json:"name"`, `json`, `name`}, {`protobuf:"PB(1,2)" json:"name"`, `protobuf`, `PB(1,2)`}, {`k0:"values contain spaces" k1:"and\ttabs"`, "k0", "values contain spaces"}, {`k0:"values contain spaces" k1:"and\ttabs"`, "k1", "and\ttabs"}, } func TestTagGet(t *testing.T) { for _, tt := range tagGetTests { if v := tt.Tag.Get(tt.Key); v != tt.Value { t.Errorf("StructTag(%#q).Get(%#q) = %#q, want %#q", tt.Tag, tt.Key, v, tt.Value) } } } func TestBytes(t *testing.T) { type B []byte x := B{1, 2, 3, 4} y := ValueOf(x).Bytes() if !bytes.Equal(x, y) { t.Fatalf("ValueOf(%v).Bytes() = %v", x, y) } if &x[0] != &y[0] { t.Errorf("ValueOf(%p).Bytes() = %p", &x[0], &y[0]) } } func TestSetBytes(t *testing.T) { type B []byte var x B y := []byte{1, 2, 3, 4} ValueOf(&x).Elem().SetBytes(y) if !bytes.Equal(x, y) { t.Fatalf("ValueOf(%v).Bytes() = %v", x, y) } if &x[0] != &y[0] { t.Errorf("ValueOf(%p).Bytes() = %p", &x[0], &y[0]) } } type Private struct { x int y **int } func (p *Private) m() { } type Public struct { X int Y **int } func (p *Public) M() { } func TestUnexported(t *testing.T) { var pub Public v := ValueOf(&pub) isValid(v.Elem().Field(0)) isValid(v.Elem().Field(1)) isValid(v.Elem().FieldByName("X")) isValid(v.Elem().FieldByName("Y")) isValid(v.Type().Method(0).Func) isNonNil(v.Elem().Field(0).Interface()) isNonNil(v.Elem().Field(1).Interface()) isNonNil(v.Elem().FieldByName("X").Interface()) isNonNil(v.Elem().FieldByName("Y").Interface()) isNonNil(v.Type().Method(0).Func.Interface()) var priv Private v = ValueOf(&priv) isValid(v.Elem().Field(0)) isValid(v.Elem().Field(1)) isValid(v.Elem().FieldByName("x")) isValid(v.Elem().FieldByName("y")) isValid(v.Type().Method(0).Func) shouldPanic(func() { v.Elem().Field(0).Interface() }) shouldPanic(func() { v.Elem().Field(1).Interface() }) shouldPanic(func() { v.Elem().FieldByName("x").Interface() }) shouldPanic(func() { v.Elem().FieldByName("y").Interface() }) shouldPanic(func() { v.Type().Method(0).Func.Interface() }) } func shouldPanic(f func()) { defer func() { if recover() == nil { panic("did not panic") } }() f() } func isNonNil(x interface{}) { if x == nil { panic("nil interface") } } func isValid(v Value) { if !v.IsValid() { panic("zero Value") } } func TestAlias(t *testing.T) { x := string("hello") v := ValueOf(&x).Elem() oldvalue := v.Interface() v.SetString("world") newvalue := v.Interface() if oldvalue != "hello" || newvalue != "world" { t.Errorf("aliasing: old=%q new=%q, want hello, world", oldvalue, newvalue) } } var V = ValueOf func EmptyInterfaceV(x interface{}) Value { return ValueOf(&x).Elem() } func ReaderV(x io.Reader) Value { return ValueOf(&x).Elem() } func ReadWriterV(x io.ReadWriter) Value { return ValueOf(&x).Elem() } type Empty struct{} type MyString string type MyBytes []byte type MyRunes []int32 type MyFunc func() type MyByte byte var convertTests = []struct { in Value out Value }{ // numbers /* Edit .+1,/\*\//-1>cat >/tmp/x.go && go run /tmp/x.go package main import "fmt" var numbers = []string{ "int8", "uint8", "int16", "uint16", "int32", "uint32", "int64", "uint64", "int", "uint", "uintptr", "float32", "float64", } func main() { // all pairs but in an unusual order, // to emit all the int8, uint8 cases // before n grows too big. n := 1 for i, f := range numbers { for _, g := range numbers[i:] { fmt.Printf("\t{V(%s(%d)), V(%s(%d))},\n", f, n, g, n) n++ if f != g { fmt.Printf("\t{V(%s(%d)), V(%s(%d))},\n", g, n, f, n) n++ } } } } */ {V(int8(1)), V(int8(1))}, {V(int8(2)), V(uint8(2))}, {V(uint8(3)), V(int8(3))}, {V(int8(4)), V(int16(4))}, {V(int16(5)), V(int8(5))}, {V(int8(6)), V(uint16(6))}, {V(uint16(7)), V(int8(7))}, {V(int8(8)), V(int32(8))}, {V(int32(9)), V(int8(9))}, {V(int8(10)), V(uint32(10))}, {V(uint32(11)), V(int8(11))}, {V(int8(12)), V(int64(12))}, {V(int64(13)), V(int8(13))}, {V(int8(14)), V(uint64(14))}, {V(uint64(15)), V(int8(15))}, {V(int8(16)), V(int(16))}, {V(int(17)), V(int8(17))}, {V(int8(18)), V(uint(18))}, {V(uint(19)), V(int8(19))}, {V(int8(20)), V(uintptr(20))}, {V(uintptr(21)), V(int8(21))}, {V(int8(22)), V(float32(22))}, {V(float32(23)), V(int8(23))}, {V(int8(24)), V(float64(24))}, {V(float64(25)), V(int8(25))}, {V(uint8(26)), V(uint8(26))}, {V(uint8(27)), V(int16(27))}, {V(int16(28)), V(uint8(28))}, {V(uint8(29)), V(uint16(29))}, {V(uint16(30)), V(uint8(30))}, {V(uint8(31)), V(int32(31))}, {V(int32(32)), V(uint8(32))}, {V(uint8(33)), V(uint32(33))}, {V(uint32(34)), V(uint8(34))}, {V(uint8(35)), V(int64(35))}, {V(int64(36)), V(uint8(36))}, {V(uint8(37)), V(uint64(37))}, {V(uint64(38)), V(uint8(38))}, {V(uint8(39)), V(int(39))}, {V(int(40)), V(uint8(40))}, {V(uint8(41)), V(uint(41))}, {V(uint(42)), V(uint8(42))}, {V(uint8(43)), V(uintptr(43))}, {V(uintptr(44)), V(uint8(44))}, {V(uint8(45)), V(float32(45))}, {V(float32(46)), V(uint8(46))}, {V(uint8(47)), V(float64(47))}, {V(float64(48)), V(uint8(48))}, {V(int16(49)), V(int16(49))}, {V(int16(50)), V(uint16(50))}, {V(uint16(51)), V(int16(51))}, {V(int16(52)), V(int32(52))}, {V(int32(53)), V(int16(53))}, {V(int16(54)), V(uint32(54))}, {V(uint32(55)), V(int16(55))}, {V(int16(56)), V(int64(56))}, {V(int64(57)), V(int16(57))}, {V(int16(58)), V(uint64(58))}, {V(uint64(59)), V(int16(59))}, {V(int16(60)), V(int(60))}, {V(int(61)), V(int16(61))}, {V(int16(62)), V(uint(62))}, {V(uint(63)), V(int16(63))}, {V(int16(64)), V(uintptr(64))}, {V(uintptr(65)), V(int16(65))}, {V(int16(66)), V(float32(66))}, {V(float32(67)), V(int16(67))}, {V(int16(68)), V(float64(68))}, {V(float64(69)), V(int16(69))}, {V(uint16(70)), V(uint16(70))}, {V(uint16(71)), V(int32(71))}, {V(int32(72)), V(uint16(72))}, {V(uint16(73)), V(uint32(73))}, {V(uint32(74)), V(uint16(74))}, {V(uint16(75)), V(int64(75))}, {V(int64(76)), V(uint16(76))}, {V(uint16(77)), V(uint64(77))}, {V(uint64(78)), V(uint16(78))}, {V(uint16(79)), V(int(79))}, {V(int(80)), V(uint16(80))}, {V(uint16(81)), V(uint(81))}, {V(uint(82)), V(uint16(82))}, {V(uint16(83)), V(uintptr(83))}, {V(uintptr(84)), V(uint16(84))}, {V(uint16(85)), V(float32(85))}, {V(float32(86)), V(uint16(86))}, {V(uint16(87)), V(float64(87))}, {V(float64(88)), V(uint16(88))}, {V(int32(89)), V(int32(89))}, {V(int32(90)), V(uint32(90))}, {V(uint32(91)), V(int32(91))}, {V(int32(92)), V(int64(92))}, {V(int64(93)), V(int32(93))}, {V(int32(94)), V(uint64(94))}, {V(uint64(95)), V(int32(95))}, {V(int32(96)), V(int(96))}, {V(int(97)), V(int32(97))}, {V(int32(98)), V(uint(98))}, {V(uint(99)), V(int32(99))}, {V(int32(100)), V(uintptr(100))}, {V(uintptr(101)), V(int32(101))}, {V(int32(102)), V(float32(102))}, {V(float32(103)), V(int32(103))}, {V(int32(104)), V(float64(104))}, {V(float64(105)), V(int32(105))}, {V(uint32(106)), V(uint32(106))}, {V(uint32(107)), V(int64(107))}, {V(int64(108)), V(uint32(108))}, {V(uint32(109)), V(uint64(109))}, {V(uint64(110)), V(uint32(110))}, {V(uint32(111)), V(int(111))}, {V(int(112)), V(uint32(112))}, {V(uint32(113)), V(uint(113))}, {V(uint(114)), V(uint32(114))}, {V(uint32(115)), V(uintptr(115))}, {V(uintptr(116)), V(uint32(116))}, {V(uint32(117)), V(float32(117))}, {V(float32(118)), V(uint32(118))}, {V(uint32(119)), V(float64(119))}, {V(float64(120)), V(uint32(120))}, {V(int64(121)), V(int64(121))}, {V(int64(122)), V(uint64(122))}, {V(uint64(123)), V(int64(123))}, {V(int64(124)), V(int(124))}, {V(int(125)), V(int64(125))}, {V(int64(126)), V(uint(126))}, {V(uint(127)), V(int64(127))}, {V(int64(128)), V(uintptr(128))}, {V(uintptr(129)), V(int64(129))}, {V(int64(130)), V(float32(130))}, {V(float32(131)), V(int64(131))}, {V(int64(132)), V(float64(132))}, {V(float64(133)), V(int64(133))}, {V(uint64(134)), V(uint64(134))}, {V(uint64(135)), V(int(135))}, {V(int(136)), V(uint64(136))}, {V(uint64(137)), V(uint(137))}, {V(uint(138)), V(uint64(138))}, {V(uint64(139)), V(uintptr(139))}, {V(uintptr(140)), V(uint64(140))}, {V(uint64(141)), V(float32(141))}, {V(float32(142)), V(uint64(142))}, {V(uint64(143)), V(float64(143))}, {V(float64(144)), V(uint64(144))}, {V(int(145)), V(int(145))}, {V(int(146)), V(uint(146))}, {V(uint(147)), V(int(147))}, {V(int(148)), V(uintptr(148))}, {V(uintptr(149)), V(int(149))}, {V(int(150)), V(float32(150))}, {V(float32(151)), V(int(151))}, {V(int(152)), V(float64(152))}, {V(float64(153)), V(int(153))}, {V(uint(154)), V(uint(154))}, {V(uint(155)), V(uintptr(155))}, {V(uintptr(156)), V(uint(156))}, {V(uint(157)), V(float32(157))}, {V(float32(158)), V(uint(158))}, {V(uint(159)), V(float64(159))}, {V(float64(160)), V(uint(160))}, {V(uintptr(161)), V(uintptr(161))}, {V(uintptr(162)), V(float32(162))}, {V(float32(163)), V(uintptr(163))}, {V(uintptr(164)), V(float64(164))}, {V(float64(165)), V(uintptr(165))}, {V(float32(166)), V(float32(166))}, {V(float32(167)), V(float64(167))}, {V(float64(168)), V(float32(168))}, {V(float64(169)), V(float64(169))}, // truncation {V(float64(1.5)), V(int(1))}, // complex {V(complex64(1i)), V(complex64(1i))}, {V(complex64(2i)), V(complex128(2i))}, {V(complex128(3i)), V(complex64(3i))}, {V(complex128(4i)), V(complex128(4i))}, // string {V(string("hello")), V(string("hello"))}, {V(string("bytes1")), V([]byte("bytes1"))}, {V([]byte("bytes2")), V(string("bytes2"))}, {V([]byte("bytes3")), V([]byte("bytes3"))}, {V(string("runes♝")), V([]rune("runes♝"))}, {V([]rune("runes♕")), V(string("runes♕"))}, {V([]rune("runes🙈🙉🙊")), V([]rune("runes🙈🙉🙊"))}, {V(int('a')), V(string("a"))}, {V(int8('a')), V(string("a"))}, {V(int16('a')), V(string("a"))}, {V(int32('a')), V(string("a"))}, {V(int64('a')), V(string("a"))}, {V(uint('a')), V(string("a"))}, {V(uint8('a')), V(string("a"))}, {V(uint16('a')), V(string("a"))}, {V(uint32('a')), V(string("a"))}, {V(uint64('a')), V(string("a"))}, {V(uintptr('a')), V(string("a"))}, {V(int(-1)), V(string("\uFFFD"))}, {V(int8(-2)), V(string("\uFFFD"))}, {V(int16(-3)), V(string("\uFFFD"))}, {V(int32(-4)), V(string("\uFFFD"))}, {V(int64(-5)), V(string("\uFFFD"))}, {V(uint(0x110001)), V(string("\uFFFD"))}, {V(uint32(0x110002)), V(string("\uFFFD"))}, {V(uint64(0x110003)), V(string("\uFFFD"))}, {V(uintptr(0x110004)), V(string("\uFFFD"))}, // named string {V(MyString("hello")), V(string("hello"))}, {V(string("hello")), V(MyString("hello"))}, {V(string("hello")), V(string("hello"))}, {V(MyString("hello")), V(MyString("hello"))}, {V(MyString("bytes1")), V([]byte("bytes1"))}, {V([]byte("bytes2")), V(MyString("bytes2"))}, {V([]byte("bytes3")), V([]byte("bytes3"))}, {V(MyString("runes♝")), V([]rune("runes♝"))}, {V([]rune("runes♕")), V(MyString("runes♕"))}, {V([]rune("runes🙈🙉🙊")), V([]rune("runes🙈🙉🙊"))}, {V([]rune("runes🙈🙉🙊")), V(MyRunes("runes🙈🙉🙊"))}, {V(MyRunes("runes🙈🙉🙊")), V([]rune("runes🙈🙉🙊"))}, {V(int('a')), V(MyString("a"))}, {V(int8('a')), V(MyString("a"))}, {V(int16('a')), V(MyString("a"))}, {V(int32('a')), V(MyString("a"))}, {V(int64('a')), V(MyString("a"))}, {V(uint('a')), V(MyString("a"))}, {V(uint8('a')), V(MyString("a"))}, {V(uint16('a')), V(MyString("a"))}, {V(uint32('a')), V(MyString("a"))}, {V(uint64('a')), V(MyString("a"))}, {V(uintptr('a')), V(MyString("a"))}, {V(int(-1)), V(MyString("\uFFFD"))}, {V(int8(-2)), V(MyString("\uFFFD"))}, {V(int16(-3)), V(MyString("\uFFFD"))}, {V(int32(-4)), V(MyString("\uFFFD"))}, {V(int64(-5)), V(MyString("\uFFFD"))}, {V(uint(0x110001)), V(MyString("\uFFFD"))}, {V(uint32(0x110002)), V(MyString("\uFFFD"))}, {V(uint64(0x110003)), V(MyString("\uFFFD"))}, {V(uintptr(0x110004)), V(MyString("\uFFFD"))}, // named []byte {V(string("bytes1")), V(MyBytes("bytes1"))}, {V(MyBytes("bytes2")), V(string("bytes2"))}, {V(MyBytes("bytes3")), V(MyBytes("bytes3"))}, {V(MyString("bytes1")), V(MyBytes("bytes1"))}, {V(MyBytes("bytes2")), V(MyString("bytes2"))}, // named []rune {V(string("runes♝")), V(MyRunes("runes♝"))}, {V(MyRunes("runes♕")), V(string("runes♕"))}, {V(MyRunes("runes🙈🙉🙊")), V(MyRunes("runes🙈🙉🙊"))}, {V(MyString("runes♝")), V(MyRunes("runes♝"))}, {V(MyRunes("runes♕")), V(MyString("runes♕"))}, // named types and equal underlying types {V(new(int)), V(new(integer))}, {V(new(integer)), V(new(int))}, {V(Empty{}), V(struct{}{})}, {V(new(Empty)), V(new(struct{}))}, {V(struct{}{}), V(Empty{})}, {V(new(struct{})), V(new(Empty))}, {V(Empty{}), V(Empty{})}, {V(MyBytes{}), V([]byte{})}, {V([]byte{}), V(MyBytes{})}, {V((func())(nil)), V(MyFunc(nil))}, {V((MyFunc)(nil)), V((func())(nil))}, // can convert *byte and *MyByte {V((*byte)(nil)), V((*MyByte)(nil))}, {V((*MyByte)(nil)), V((*byte)(nil))}, // cannot convert mismatched array sizes {V([2]byte{}), V([2]byte{})}, {V([3]byte{}), V([3]byte{})}, // cannot convert other instances {V((**byte)(nil)), V((**byte)(nil))}, {V((**MyByte)(nil)), V((**MyByte)(nil))}, {V((chan byte)(nil)), V((chan byte)(nil))}, {V((chan MyByte)(nil)), V((chan MyByte)(nil))}, {V(([]byte)(nil)), V(([]byte)(nil))}, {V(([]MyByte)(nil)), V(([]MyByte)(nil))}, {V((map[int]byte)(nil)), V((map[int]byte)(nil))}, {V((map[int]MyByte)(nil)), V((map[int]MyByte)(nil))}, {V((map[byte]int)(nil)), V((map[byte]int)(nil))}, {V((map[MyByte]int)(nil)), V((map[MyByte]int)(nil))}, {V([2]byte{}), V([2]byte{})}, {V([2]MyByte{}), V([2]MyByte{})}, // other {V((***int)(nil)), V((***int)(nil))}, {V((***byte)(nil)), V((***byte)(nil))}, {V((***int32)(nil)), V((***int32)(nil))}, {V((***int64)(nil)), V((***int64)(nil))}, {V((chan int)(nil)), V((<-chan int)(nil))}, {V((chan int)(nil)), V((chan<- int)(nil))}, {V((chan string)(nil)), V((<-chan string)(nil))}, {V((chan string)(nil)), V((chan<- string)(nil))}, {V((chan byte)(nil)), V((chan byte)(nil))}, {V((chan MyByte)(nil)), V((chan MyByte)(nil))}, {V((map[int]bool)(nil)), V((map[int]bool)(nil))}, {V((map[int]byte)(nil)), V((map[int]byte)(nil))}, {V((map[uint]bool)(nil)), V((map[uint]bool)(nil))}, {V([]uint(nil)), V([]uint(nil))}, {V([]int(nil)), V([]int(nil))}, {V(new(interface{})), V(new(interface{}))}, {V(new(io.Reader)), V(new(io.Reader))}, {V(new(io.Writer)), V(new(io.Writer))}, // interfaces {V(int(1)), EmptyInterfaceV(int(1))}, {V(string("hello")), EmptyInterfaceV(string("hello"))}, {V(new(bytes.Buffer)), ReaderV(new(bytes.Buffer))}, {ReadWriterV(new(bytes.Buffer)), ReaderV(new(bytes.Buffer))}, {V(new(bytes.Buffer)), ReadWriterV(new(bytes.Buffer))}, } func TestConvert(t *testing.T) { canConvert := map[[2]Type]bool{} all := map[Type]bool{} for _, tt := range convertTests { t1 := tt.in.Type() if !t1.ConvertibleTo(t1) { t.Errorf("(%s).ConvertibleTo(%s) = false, want true", t1, t1) continue } t2 := tt.out.Type() if !t1.ConvertibleTo(t2) { t.Errorf("(%s).ConvertibleTo(%s) = false, want true", t1, t2) continue } all[t1] = true all[t2] = true canConvert[[2]Type{t1, t2}] = true // vout1 represents the in value converted to the in type. v1 := tt.in vout1 := v1.Convert(t1) out1 := vout1.Interface() if vout1.Type() != tt.in.Type() || !DeepEqual(out1, tt.in.Interface()) { t.Errorf("ValueOf(%T(%[1]v)).Convert(%s) = %T(%[3]v), want %T(%[4]v)", tt.in.Interface(), t1, out1, tt.in.Interface()) } // vout2 represents the in value converted to the out type. vout2 := v1.Convert(t2) out2 := vout2.Interface() if vout2.Type() != tt.out.Type() || !DeepEqual(out2, tt.out.Interface()) { t.Errorf("ValueOf(%T(%[1]v)).Convert(%s) = %T(%[3]v), want %T(%[4]v)", tt.in.Interface(), t2, out2, tt.out.Interface()) } // vout3 represents a new value of the out type, set to vout2. This makes // sure the converted value vout2 is really usable as a regular value. vout3 := New(t2).Elem() vout3.Set(vout2) out3 := vout3.Interface() if vout3.Type() != tt.out.Type() || !DeepEqual(out3, tt.out.Interface()) { t.Errorf("Set(ValueOf(%T(%[1]v)).Convert(%s)) = %T(%[3]v), want %T(%[4]v)", tt.in.Interface(), t2, out3, tt.out.Interface()) } if IsRO(v1) { t.Errorf("table entry %v is RO, should not be", v1) } if IsRO(vout1) { t.Errorf("self-conversion output %v is RO, should not be", vout1) } if IsRO(vout2) { t.Errorf("conversion output %v is RO, should not be", vout2) } if IsRO(vout3) { t.Errorf("set(conversion output) %v is RO, should not be", vout3) } if !IsRO(MakeRO(v1).Convert(t1)) { t.Errorf("RO self-conversion output %v is not RO, should be", v1) } if !IsRO(MakeRO(v1).Convert(t2)) { t.Errorf("RO conversion output %v is not RO, should be", v1) } } // Assume that of all the types we saw during the tests, // if there wasn't an explicit entry for a conversion between // a pair of types, then it's not to be allowed. This checks for // things like 'int64' converting to '*int'. for t1 := range all { for t2 := range all { expectOK := t1 == t2 || canConvert[[2]Type{t1, t2}] || t2.Kind() == Interface && t2.NumMethod() == 0 if ok := t1.ConvertibleTo(t2); ok != expectOK { t.Errorf("(%s).ConvertibleTo(%s) = %v, want %v", t1, t2, ok, expectOK) } } } } type ComparableStruct struct { X int } type NonComparableStruct struct { X int Y map[string]int } var comparableTests = []struct { typ Type ok bool }{ {TypeOf(1), true}, {TypeOf("hello"), true}, {TypeOf(new(byte)), true}, {TypeOf((func())(nil)), false}, {TypeOf([]byte{}), false}, {TypeOf(map[string]int{}), false}, {TypeOf(make(chan int)), true}, {TypeOf(1.5), true}, {TypeOf(false), true}, {TypeOf(1i), true}, {TypeOf(ComparableStruct{}), true}, {TypeOf(NonComparableStruct{}), false}, {TypeOf([10]map[string]int{}), false}, {TypeOf([10]string{}), true}, {TypeOf(new(interface{})).Elem(), true}, } func TestComparable(t *testing.T) { for _, tt := range comparableTests { if ok := tt.typ.Comparable(); ok != tt.ok { t.Errorf("TypeOf(%v).Comparable() = %v, want %v", tt.typ, ok, tt.ok) } } } func TestOverflow(t *testing.T) { if ovf := V(float64(0)).OverflowFloat(1e300); ovf { t.Errorf("%v wrongly overflows float64", 1e300) } maxFloat32 := float64((1<<24 - 1) << (127 - 23)) if ovf := V(float32(0)).OverflowFloat(maxFloat32); ovf { t.Errorf("%v wrongly overflows float32", maxFloat32) } ovfFloat32 := float64((1<<24-1)<<(127-23) + 1<<(127-52)) if ovf := V(float32(0)).OverflowFloat(ovfFloat32); !ovf { t.Errorf("%v should overflow float32", ovfFloat32) } if ovf := V(float32(0)).OverflowFloat(-ovfFloat32); !ovf { t.Errorf("%v should overflow float32", -ovfFloat32) } maxInt32 := int64(0x7fffffff) if ovf := V(int32(0)).OverflowInt(maxInt32); ovf { t.Errorf("%v wrongly overflows int32", maxInt32) } if ovf := V(int32(0)).OverflowInt(-1 << 31); ovf { t.Errorf("%v wrongly overflows int32", -int64(1)<<31) } ovfInt32 := int64(1 << 31) if ovf := V(int32(0)).OverflowInt(ovfInt32); !ovf { t.Errorf("%v should overflow int32", ovfInt32) } maxUint32 := uint64(0xffffffff) if ovf := V(uint32(0)).OverflowUint(maxUint32); ovf { t.Errorf("%v wrongly overflows uint32", maxUint32) } ovfUint32 := uint64(1 << 32) if ovf := V(uint32(0)).OverflowUint(ovfUint32); !ovf { t.Errorf("%v should overflow uint32", ovfUint32) } } func checkSameType(t *testing.T, x, y interface{}) { if TypeOf(x) != TypeOf(y) { t.Errorf("did not find preexisting type for %s (vs %s)", TypeOf(x), TypeOf(y)) } } func TestArrayOf(t *testing.T) { // check construction and use of type not in binary for _, table := range []struct { n int value func(i int) interface{} comparable bool want string }{ { n: 0, value: func(i int) interface{} { type Tint int; return Tint(i) }, comparable: true, want: "[]", }, { n: 10, value: func(i int) interface{} { type Tint int; return Tint(i) }, comparable: true, want: "[0 1 2 3 4 5 6 7 8 9]", }, { n: 10, value: func(i int) interface{} { type Tfloat float64; return Tfloat(i) }, comparable: true, want: "[0 1 2 3 4 5 6 7 8 9]", }, { n: 10, value: func(i int) interface{} { type Tstring string; return Tstring(strconv.Itoa(i)) }, comparable: true, want: "[0 1 2 3 4 5 6 7 8 9]", }, { n: 10, value: func(i int) interface{} { type Tstruct struct{ V int }; return Tstruct{i} }, comparable: true, want: "[{0} {1} {2} {3} {4} {5} {6} {7} {8} {9}]", }, { n: 10, value: func(i int) interface{} { type Tint int; return []Tint{Tint(i)} }, comparable: false, want: "[[0] [1] [2] [3] [4] [5] [6] [7] [8] [9]]", }, { n: 10, value: func(i int) interface{} { type Tint int; return [1]Tint{Tint(i)} }, comparable: true, want: "[[0] [1] [2] [3] [4] [5] [6] [7] [8] [9]]", }, { n: 10, value: func(i int) interface{} { type Tstruct struct{ V [1]int }; return Tstruct{[1]int{i}} }, comparable: true, want: "[{[0]} {[1]} {[2]} {[3]} {[4]} {[5]} {[6]} {[7]} {[8]} {[9]}]", }, { n: 10, value: func(i int) interface{} { type Tstruct struct{ V []int }; return Tstruct{[]int{i}} }, comparable: false, want: "[{[0]} {[1]} {[2]} {[3]} {[4]} {[5]} {[6]} {[7]} {[8]} {[9]}]", }, { n: 10, value: func(i int) interface{} { type TstructUV struct{ U, V int }; return TstructUV{i, i} }, comparable: true, want: "[{0 0} {1 1} {2 2} {3 3} {4 4} {5 5} {6 6} {7 7} {8 8} {9 9}]", }, { n: 10, value: func(i int) interface{} { type TstructUV struct { U int V float64 } return TstructUV{i, float64(i)} }, comparable: true, want: "[{0 0} {1 1} {2 2} {3 3} {4 4} {5 5} {6 6} {7 7} {8 8} {9 9}]", }, } { at := ArrayOf(table.n, TypeOf(table.value(0))) v := New(at).Elem() vok := New(at).Elem() vnot := New(at).Elem() for i := 0; i < v.Len(); i++ { v.Index(i).Set(ValueOf(table.value(i))) vok.Index(i).Set(ValueOf(table.value(i))) j := i if i+1 == v.Len() { j = i + 1 } vnot.Index(i).Set(ValueOf(table.value(j))) // make it differ only by last element } s := fmt.Sprint(v.Interface()) if s != table.want { t.Errorf("constructed array = %s, want %s", s, table.want) } if table.comparable != at.Comparable() { t.Errorf("constructed array (%#v) is comparable=%v, want=%v", v.Interface(), at.Comparable(), table.comparable) } if table.comparable { if table.n > 0 { if DeepEqual(vnot.Interface(), v.Interface()) { t.Errorf( "arrays (%#v) compare ok (but should not)", v.Interface(), ) } } if !DeepEqual(vok.Interface(), v.Interface()) { t.Errorf( "arrays (%#v) compare NOT-ok (but should)", v.Interface(), ) } } } // check that type already in binary is found type T int checkSameType(t, Zero(ArrayOf(5, TypeOf(T(1)))).Interface(), [5]T{}) } func TestArrayOfGC(t *testing.T) { type T *uintptr tt := TypeOf(T(nil)) const n = 100 var x []interface{} for i := 0; i < n; i++ { v := New(ArrayOf(n, tt)).Elem() for j := 0; j < v.Len(); j++ { p := new(uintptr) *p = uintptr(i*n + j) v.Index(j).Set(ValueOf(p).Convert(tt)) } x = append(x, v.Interface()) } runtime.GC() for i, xi := range x { v := ValueOf(xi) for j := 0; j < v.Len(); j++ { k := v.Index(j).Elem().Interface() if k != uintptr(i*n+j) { t.Errorf("lost x[%d][%d] = %d, want %d", i, j, k, i*n+j) } } } } func TestArrayOfAlg(t *testing.T) { at := ArrayOf(6, TypeOf(byte(0))) v1 := New(at).Elem() v2 := New(at).Elem() if v1.Interface() != v1.Interface() { t.Errorf("constructed array %v not equal to itself", v1.Interface()) } v1.Index(5).Set(ValueOf(byte(1))) if i1, i2 := v1.Interface(), v2.Interface(); i1 == i2 { t.Errorf("constructed arrays %v and %v should not be equal", i1, i2) } at = ArrayOf(6, TypeOf([]int(nil))) v1 = New(at).Elem() shouldPanic(func() { _ = v1.Interface() == v1.Interface() }) } func TestArrayOfGenericAlg(t *testing.T) { at1 := ArrayOf(5, TypeOf(string(""))) at := ArrayOf(6, at1) v1 := New(at).Elem() v2 := New(at).Elem() if v1.Interface() != v1.Interface() { t.Errorf("constructed array %v not equal to itself", v1.Interface()) } v1.Index(0).Index(0).Set(ValueOf("abc")) v2.Index(0).Index(0).Set(ValueOf("efg")) if i1, i2 := v1.Interface(), v2.Interface(); i1 == i2 { t.Errorf("constructed arrays %v and %v should not be equal", i1, i2) } v1.Index(0).Index(0).Set(ValueOf("abc")) v2.Index(0).Index(0).Set(ValueOf((v1.Index(0).Index(0).String() + " ")[:3])) if i1, i2 := v1.Interface(), v2.Interface(); i1 != i2 { t.Errorf("constructed arrays %v and %v should be equal", i1, i2) } // Test hash m := MakeMap(MapOf(at, TypeOf(int(0)))) m.SetMapIndex(v1, ValueOf(1)) if i1, i2 := v1.Interface(), v2.Interface(); !m.MapIndex(v2).IsValid() { t.Errorf("constructed arrays %v and %v have different hashes", i1, i2) } } func TestArrayOfDirectIface(t *testing.T) { { type T [1]*byte i1 := Zero(TypeOf(T{})).Interface() v1 := ValueOf(&i1).Elem() p1 := v1.InterfaceData()[1] i2 := Zero(ArrayOf(1, PtrTo(TypeOf(int8(0))))).Interface() v2 := ValueOf(&i2).Elem() p2 := v2.InterfaceData()[1] if p1 != 0 { t.Errorf("got p1=%v. want=%v", p1, nil) } if p2 != 0 { t.Errorf("got p2=%v. want=%v", p2, nil) } } { type T [0]*byte i1 := Zero(TypeOf(T{})).Interface() v1 := ValueOf(&i1).Elem() p1 := v1.InterfaceData()[1] i2 := Zero(ArrayOf(0, PtrTo(TypeOf(int8(0))))).Interface() v2 := ValueOf(&i2).Elem() p2 := v2.InterfaceData()[1] if p1 == 0 { t.Errorf("got p1=%v. want=not-%v", p1, nil) } if p2 == 0 { t.Errorf("got p2=%v. want=not-%v", p2, nil) } } } func TestSliceOf(t *testing.T) { // check construction and use of type not in binary type T int st := SliceOf(TypeOf(T(1))) v := MakeSlice(st, 10, 10) runtime.GC() for i := 0; i < v.Len(); i++ { v.Index(i).Set(ValueOf(T(i))) runtime.GC() } s := fmt.Sprint(v.Interface()) want := "[0 1 2 3 4 5 6 7 8 9]" if s != want { t.Errorf("constructed slice = %s, want %s", s, want) } // check that type already in binary is found type T1 int checkSameType(t, Zero(SliceOf(TypeOf(T1(1)))).Interface(), []T1{}) } func TestSliceOverflow(t *testing.T) { // check that MakeSlice panics when size of slice overflows uint const S = 1e6 s := uint(S) l := (1<<(unsafe.Sizeof((*byte)(nil))*8)-1)/s + 1 if l*s >= s { t.Fatal("slice size does not overflow") } var x [S]byte st := SliceOf(TypeOf(x)) defer func() { err := recover() if err == nil { t.Fatal("slice overflow does not panic") } }() MakeSlice(st, int(l), int(l)) } func TestSliceOfGC(t *testing.T) { type T *uintptr tt := TypeOf(T(nil)) st := SliceOf(tt) const n = 100 var x []interface{} for i := 0; i < n; i++ { v := MakeSlice(st, n, n) for j := 0; j < v.Len(); j++ { p := new(uintptr) *p = uintptr(i*n + j) v.Index(j).Set(ValueOf(p).Convert(tt)) } x = append(x, v.Interface()) } runtime.GC() for i, xi := range x { v := ValueOf(xi) for j := 0; j < v.Len(); j++ { k := v.Index(j).Elem().Interface() if k != uintptr(i*n+j) { t.Errorf("lost x[%d][%d] = %d, want %d", i, j, k, i*n+j) } } } } func TestChanOf(t *testing.T) { // check construction and use of type not in binary type T string ct := ChanOf(BothDir, TypeOf(T(""))) v := MakeChan(ct, 2) runtime.GC() v.Send(ValueOf(T("hello"))) runtime.GC() v.Send(ValueOf(T("world"))) runtime.GC() sv1, _ := v.Recv() sv2, _ := v.Recv() s1 := sv1.String() s2 := sv2.String() if s1 != "hello" || s2 != "world" { t.Errorf("constructed chan: have %q, %q, want %q, %q", s1, s2, "hello", "world") } // check that type already in binary is found type T1 int checkSameType(t, Zero(ChanOf(BothDir, TypeOf(T1(1)))).Interface(), (chan T1)(nil)) } func TestChanOfDir(t *testing.T) { // check construction and use of type not in binary type T string crt := ChanOf(RecvDir, TypeOf(T(""))) cst := ChanOf(SendDir, TypeOf(T(""))) // check that type already in binary is found type T1 int checkSameType(t, Zero(ChanOf(RecvDir, TypeOf(T1(1)))).Interface(), (<-chan T1)(nil)) checkSameType(t, Zero(ChanOf(SendDir, TypeOf(T1(1)))).Interface(), (chan<- T1)(nil)) // check String form of ChanDir if crt.ChanDir().String() != "<-chan" { t.Errorf("chan dir: have %q, want %q", crt.ChanDir().String(), "<-chan") } if cst.ChanDir().String() != "chan<-" { t.Errorf("chan dir: have %q, want %q", cst.ChanDir().String(), "chan<-") } } func TestChanOfGC(t *testing.T) { done := make(chan bool, 1) go func() { select { case <-done: case <-time.After(5 * time.Second): panic("deadlock in TestChanOfGC") } }() defer func() { done <- true }() type T *uintptr tt := TypeOf(T(nil)) ct := ChanOf(BothDir, tt) // NOTE: The garbage collector handles allocated channels specially, // so we have to save pointers to channels in x; the pointer code will // use the gc info in the newly constructed chan type. const n = 100 var x []interface{} for i := 0; i < n; i++ { v := MakeChan(ct, n) for j := 0; j < n; j++ { p := new(uintptr) *p = uintptr(i*n + j) v.Send(ValueOf(p).Convert(tt)) } pv := New(ct) pv.Elem().Set(v) x = append(x, pv.Interface()) } runtime.GC() for i, xi := range x { v := ValueOf(xi).Elem() for j := 0; j < n; j++ { pv, _ := v.Recv() k := pv.Elem().Interface() if k != uintptr(i*n+j) { t.Errorf("lost x[%d][%d] = %d, want %d", i, j, k, i*n+j) } } } } func TestMapOf(t *testing.T) { // check construction and use of type not in binary type K string type V float64 v := MakeMap(MapOf(TypeOf(K("")), TypeOf(V(0)))) runtime.GC() v.SetMapIndex(ValueOf(K("a")), ValueOf(V(1))) runtime.GC() s := fmt.Sprint(v.Interface()) want := "map[a:1]" if s != want { t.Errorf("constructed map = %s, want %s", s, want) } // check that type already in binary is found checkSameType(t, Zero(MapOf(TypeOf(V(0)), TypeOf(K("")))).Interface(), map[V]K(nil)) // check that invalid key type panics shouldPanic(func() { MapOf(TypeOf((func())(nil)), TypeOf(false)) }) } func TestMapOfGCKeys(t *testing.T) { type T *uintptr tt := TypeOf(T(nil)) mt := MapOf(tt, TypeOf(false)) // NOTE: The garbage collector handles allocated maps specially, // so we have to save pointers to maps in x; the pointer code will // use the gc info in the newly constructed map type. const n = 100 var x []interface{} for i := 0; i < n; i++ { v := MakeMap(mt) for j := 0; j < n; j++ { p := new(uintptr) *p = uintptr(i*n + j) v.SetMapIndex(ValueOf(p).Convert(tt), ValueOf(true)) } pv := New(mt) pv.Elem().Set(v) x = append(x, pv.Interface()) } runtime.GC() for i, xi := range x { v := ValueOf(xi).Elem() var out []int for _, kv := range v.MapKeys() { out = append(out, int(kv.Elem().Interface().(uintptr))) } sort.Ints(out) for j, k := range out { if k != i*n+j { t.Errorf("lost x[%d][%d] = %d, want %d", i, j, k, i*n+j) } } } } func TestMapOfGCValues(t *testing.T) { type T *uintptr tt := TypeOf(T(nil)) mt := MapOf(TypeOf(1), tt) // NOTE: The garbage collector handles allocated maps specially, // so we have to save pointers to maps in x; the pointer code will // use the gc info in the newly constructed map type. const n = 100 var x []interface{} for i := 0; i < n; i++ { v := MakeMap(mt) for j := 0; j < n; j++ { p := new(uintptr) *p = uintptr(i*n + j) v.SetMapIndex(ValueOf(j), ValueOf(p).Convert(tt)) } pv := New(mt) pv.Elem().Set(v) x = append(x, pv.Interface()) } runtime.GC() for i, xi := range x { v := ValueOf(xi).Elem() for j := 0; j < n; j++ { k := v.MapIndex(ValueOf(j)).Elem().Interface().(uintptr) if k != uintptr(i*n+j) { t.Errorf("lost x[%d][%d] = %d, want %d", i, j, k, i*n+j) } } } } func TestTypelinksSorted(t *testing.T) { var last string for i, n := range TypeLinks() { if n < last { t.Errorf("typelinks not sorted: %q [%d] > %q [%d]", last, i-1, n, i) } last = n } } func TestFuncOf(t *testing.T) { // check construction and use of type not in binary type K string type V float64 fn := func(args []Value) []Value { if len(args) != 1 { t.Errorf("args == %v, want exactly one arg", args) } else if args[0].Type() != TypeOf(K("")) { t.Errorf("args[0] is type %v, want %v", args[0].Type, TypeOf(K(""))) } else if args[0].String() != "gopher" { t.Errorf("args[0] = %q, want %q", args[0].String(), "gopher") } return []Value{ValueOf(V(3.14))} } v := MakeFunc(FuncOf([]Type{TypeOf(K(""))}, []Type{TypeOf(V(0))}, false), fn) outs := v.Call([]Value{ValueOf(K("gopher"))}) if len(outs) != 1 { t.Fatalf("v.Call returned %v, want exactly one result", outs) } else if outs[0].Type() != TypeOf(V(0)) { t.Fatalf("c.Call[0] is type %v, want %v", outs[0].Type, TypeOf(V(0))) } f := outs[0].Float() if f != 3.14 { t.Errorf("constructed func returned %f, want %f", f, 3.14) } // check that types already in binary are found type T1 int testCases := []struct { in, out []Type variadic bool want interface{} }{ {in: []Type{TypeOf(T1(0))}, want: (func(T1))(nil)}, {in: []Type{TypeOf(int(0))}, want: (func(int))(nil)}, {in: []Type{SliceOf(TypeOf(int(0)))}, variadic: true, want: (func(...int))(nil)}, {in: []Type{TypeOf(int(0))}, out: []Type{TypeOf(false)}, want: (func(int) bool)(nil)}, {in: []Type{TypeOf(int(0))}, out: []Type{TypeOf(false), TypeOf("")}, want: (func(int) (bool, string))(nil)}, } for _, tt := range testCases { checkSameType(t, Zero(FuncOf(tt.in, tt.out, tt.variadic)).Interface(), tt.want) } // check that variadic requires last element be a slice. FuncOf([]Type{TypeOf(1), TypeOf(""), SliceOf(TypeOf(false))}, nil, true) shouldPanic(func() { FuncOf([]Type{TypeOf(0), TypeOf(""), TypeOf(false)}, nil, true) }) shouldPanic(func() { FuncOf(nil, nil, true) }) } type B1 struct { X int Y int Z int } func BenchmarkFieldByName1(b *testing.B) { t := TypeOf(B1{}) for i := 0; i < b.N; i++ { t.FieldByName("Z") } } func BenchmarkFieldByName2(b *testing.B) { t := TypeOf(S3{}) for i := 0; i < b.N; i++ { t.FieldByName("B") } } type R0 struct { *R1 *R2 *R3 *R4 } type R1 struct { *R5 *R6 *R7 *R8 } type R2 R1 type R3 R1 type R4 R1 type R5 struct { *R9 *R10 *R11 *R12 } type R6 R5 type R7 R5 type R8 R5 type R9 struct { *R13 *R14 *R15 *R16 } type R10 R9 type R11 R9 type R12 R9 type R13 struct { *R17 *R18 *R19 *R20 } type R14 R13 type R15 R13 type R16 R13 type R17 struct { *R21 *R22 *R23 *R24 } type R18 R17 type R19 R17 type R20 R17 type R21 struct { X int } type R22 R21 type R23 R21 type R24 R21 func TestEmbed(t *testing.T) { typ := TypeOf(R0{}) f, ok := typ.FieldByName("X") if ok { t.Fatalf(`FieldByName("X") should fail, returned %v`, f.Index) } } func BenchmarkFieldByName3(b *testing.B) { t := TypeOf(R0{}) for i := 0; i < b.N; i++ { t.FieldByName("X") } } type S struct { i1 int64 i2 int64 } func BenchmarkInterfaceBig(b *testing.B) { v := ValueOf(S{}) for i := 0; i < b.N; i++ { v.Interface() } b.StopTimer() } func TestAllocsInterfaceBig(t *testing.T) { if testing.Short() { t.Skip("skipping malloc count in short mode") } v := ValueOf(S{}) if allocs := testing.AllocsPerRun(100, func() { v.Interface() }); allocs > 0 { t.Error("allocs:", allocs) } } func BenchmarkInterfaceSmall(b *testing.B) { v := ValueOf(int64(0)) for i := 0; i < b.N; i++ { v.Interface() } } func TestAllocsInterfaceSmall(t *testing.T) { if testing.Short() { t.Skip("skipping malloc count in short mode") } v := ValueOf(int64(0)) if allocs := testing.AllocsPerRun(100, func() { v.Interface() }); allocs > 0 { t.Error("allocs:", allocs) } } // An exhaustive is a mechanism for writing exhaustive or stochastic tests. // The basic usage is: // // for x.Next() { // ... code using x.Maybe() or x.Choice(n) to create test cases ... // } // // Each iteration of the loop returns a different set of results, until all // possible result sets have been explored. It is okay for different code paths // to make different method call sequences on x, but there must be no // other source of non-determinism in the call sequences. // // When faced with a new decision, x chooses randomly. Future explorations // of that path will choose successive values for the result. Thus, stopping // the loop after a fixed number of iterations gives somewhat stochastic // testing. // // Example: // // for x.Next() { // v := make([]bool, x.Choose(4)) // for i := range v { // v[i] = x.Maybe() // } // fmt.Println(v) // } // // prints (in some order): // // [] // [false] // [true] // [false false] // [false true] // ... // [true true] // [false false false] // ... // [true true true] // [false false false false] // ... // [true true true true] // type exhaustive struct { r *rand.Rand pos int last []choice } type choice struct { off int n int max int } func (x *exhaustive) Next() bool { if x.r == nil { x.r = rand.New(rand.NewSource(time.Now().UnixNano())) } x.pos = 0 if x.last == nil { x.last = []choice{} return true } for i := len(x.last) - 1; i >= 0; i-- { c := &x.last[i] if c.n+1 < c.max { c.n++ x.last = x.last[:i+1] return true } } return false } func (x *exhaustive) Choose(max int) int { if x.pos >= len(x.last) { x.last = append(x.last, choice{x.r.Intn(max), 0, max}) } c := &x.last[x.pos] x.pos++ if c.max != max { panic("inconsistent use of exhaustive tester") } return (c.n + c.off) % max } func (x *exhaustive) Maybe() bool { return x.Choose(2) == 1 } func GCFunc(args []Value) []Value { runtime.GC() return []Value{} } func TestReflectFuncTraceback(t *testing.T) { f := MakeFunc(TypeOf(func() {}), GCFunc) f.Call([]Value{}) } func TestReflectMethodTraceback(t *testing.T) { p := Point{3, 4} m := ValueOf(p).MethodByName("GCMethod") i := ValueOf(m.Interface()).Call([]Value{ValueOf(5)})[0].Int() if i != 8 { t.Errorf("Call returned %d; want 8", i) } } func TestBigZero(t *testing.T) { const size = 1 << 10 var v [size]byte z := Zero(ValueOf(v).Type()).Interface().([size]byte) for i := 0; i < size; i++ { if z[i] != 0 { t.Fatalf("Zero object not all zero, index %d", i) } } } func TestFieldByIndexNil(t *testing.T) { type P struct { F int } type T struct { *P } v := ValueOf(T{}) v.FieldByName("P") // should be fine defer func() { if err := recover(); err == nil { t.Fatalf("no error") } else if !strings.Contains(fmt.Sprint(err), "nil pointer to embedded struct") { t.Fatalf(`err=%q, wanted error containing "nil pointer to embedded struct"`, err) } }() v.FieldByName("F") // should panic t.Fatalf("did not panic") } // Given // type Outer struct { // *Inner // ... // } // the compiler generates the implementation of (*Outer).M dispatching to the embedded Inner. // The implementation is logically: // func (p *Outer) M() { // (p.Inner).M() // } // but since the only change here is the replacement of one pointer receiver with another, // the actual generated code overwrites the original receiver with the p.Inner pointer and // then jumps to the M method expecting the *Inner receiver. // // During reflect.Value.Call, we create an argument frame and the associated data structures // to describe it to the garbage collector, populate the frame, call reflect.call to // run a function call using that frame, and then copy the results back out of the frame. // The reflect.call function does a memmove of the frame structure onto the // stack (to set up the inputs), runs the call, and the memmoves the stack back to // the frame structure (to preserve the outputs). // // Originally reflect.call did not distinguish inputs from outputs: both memmoves // were for the full stack frame. However, in the case where the called function was // one of these wrappers, the rewritten receiver is almost certainly a different type // than the original receiver. This is not a problem on the stack, where we use the // program counter to determine the type information and understand that // during (*Outer).M the receiver is an *Outer while during (*Inner).M the receiver in the same // memory word is now an *Inner. But in the statically typed argument frame created // by reflect, the receiver is always an *Outer. Copying the modified receiver pointer // off the stack into the frame will store an *Inner there, and then if a garbage collection // happens to scan that argument frame before it is discarded, it will scan the *Inner // memory as if it were an *Outer. If the two have different memory layouts, the // collection will intepret the memory incorrectly. // // One such possible incorrect interpretation is to treat two arbitrary memory words // (Inner.P1 and Inner.P2 below) as an interface (Outer.R below). Because interpreting // an interface requires dereferencing the itab word, the misinterpretation will try to // deference Inner.P1, causing a crash during garbage collection. // // This came up in a real program in issue 7725. type Outer struct { *Inner R io.Reader } type Inner struct { X *Outer P1 uintptr P2 uintptr } func (pi *Inner) M() { // Clear references to pi so that the only way the // garbage collection will find the pointer is in the // argument frame, typed as a *Outer. pi.X.Inner = nil // Set up an interface value that will cause a crash. // P1 = 1 is a non-zero, so the interface looks non-nil. // P2 = pi ensures that the data word points into the // allocated heap; if not the collection skips the interface // value as irrelevant, without dereferencing P1. pi.P1 = 1 pi.P2 = uintptr(unsafe.Pointer(pi)) } func TestCallMethodJump(t *testing.T) { // In reflect.Value.Call, trigger a garbage collection after reflect.call // returns but before the args frame has been discarded. // This is a little clumsy but makes the failure repeatable. *CallGC = true p := &Outer{Inner: new(Inner)} p.Inner.X = p ValueOf(p).Method(0).Call(nil) // Stop garbage collecting during reflect.call. *CallGC = false } func TestMakeFuncStackCopy(t *testing.T) { target := func(in []Value) []Value { runtime.GC() useStack(16) return []Value{ValueOf(9)} } var concrete func(*int, int) int fn := MakeFunc(ValueOf(concrete).Type(), target) ValueOf(&concrete).Elem().Set(fn) x := concrete(nil, 7) if x != 9 { t.Errorf("have %#q want 9", x) } } // use about n KB of stack func useStack(n int) { if n == 0 { return } var b [1024]byte // makes frame about 1KB useStack(n - 1 + int(b[99])) } type Impl struct{} func (Impl) f() {} func TestValueString(t *testing.T) { rv := ValueOf(Impl{}) if rv.String() != "<reflect_test.Impl Value>" { t.Errorf("ValueOf(Impl{}).String() = %q, want %q", rv.String(), "<reflect_test.Impl Value>") } method := rv.Method(0) if method.String() != "<func() Value>" { t.Errorf("ValueOf(Impl{}).Method(0).String() = %q, want %q", method.String(), "<func() Value>") } } func TestInvalid(t *testing.T) { // Used to have inconsistency between IsValid() and Kind() != Invalid. type T struct{ v interface{} } v := ValueOf(T{}).Field(0) if v.IsValid() != true || v.Kind() != Interface { t.Errorf("field: IsValid=%v, Kind=%v, want true, Interface", v.IsValid(), v.Kind()) } v = v.Elem() if v.IsValid() != false || v.Kind() != Invalid { t.Errorf("field elem: IsValid=%v, Kind=%v, want false, Invalid", v.IsValid(), v.Kind()) } } // Issue 8917. func TestLargeGCProg(t *testing.T) { fv := ValueOf(func([256]*byte) {}) fv.Call([]Value{ValueOf([256]*byte{})}) } // Issue 9179. func TestCallGC(t *testing.T) { f := func(a, b, c, d, e string) { } g := func(in []Value) []Value { runtime.GC() return nil } typ := ValueOf(f).Type() f2 := MakeFunc(typ, g).Interface().(func(string, string, string, string, string)) f2("four", "five5", "six666", "seven77", "eight888") } type funcLayoutTest struct { rcvr, t Type size, argsize, retOffset uintptr stack []byte // pointer bitmap: 1 is pointer, 0 is scalar (or uninitialized) gc []byte } var funcLayoutTests []funcLayoutTest func init() { var argAlign uintptr = PtrSize if runtime.GOARCH == "amd64p32" { argAlign = 2 * PtrSize } roundup := func(x uintptr, a uintptr) uintptr { return (x + a - 1) / a * a } funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ nil, ValueOf(func(a, b string) string { return "" }).Type(), 6 * PtrSize, 4 * PtrSize, 4 * PtrSize, []byte{1, 0, 1}, []byte{1, 0, 1, 0, 1}, }) var r []byte if PtrSize == 4 { r = []byte{0, 0, 0, 1} } else { r = []byte{0, 0, 1} } funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ nil, ValueOf(func(a, b, c uint32, p *byte, d uint16) {}).Type(), roundup(roundup(3*4, PtrSize)+PtrSize+2, argAlign), roundup(3*4, PtrSize) + PtrSize + 2, roundup(roundup(3*4, PtrSize)+PtrSize+2, argAlign), r, r, }) funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ nil, ValueOf(func(a map[int]int, b uintptr, c interface{}) {}).Type(), 4 * PtrSize, 4 * PtrSize, 4 * PtrSize, []byte{1, 0, 1, 1}, []byte{1, 0, 1, 1}, }) type S struct { a, b uintptr c, d *byte } funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ nil, ValueOf(func(a S) {}).Type(), 4 * PtrSize, 4 * PtrSize, 4 * PtrSize, []byte{0, 0, 1, 1}, []byte{0, 0, 1, 1}, }) funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ ValueOf((*byte)(nil)).Type(), ValueOf(func(a uintptr, b *int) {}).Type(), roundup(3*PtrSize, argAlign), 3 * PtrSize, roundup(3*PtrSize, argAlign), []byte{1, 0, 1}, []byte{1, 0, 1}, }) funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ nil, ValueOf(func(a uintptr) {}).Type(), roundup(PtrSize, argAlign), PtrSize, roundup(PtrSize, argAlign), []byte{}, []byte{}, }) funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ nil, ValueOf(func() uintptr { return 0 }).Type(), PtrSize, 0, 0, []byte{}, []byte{}, }) funcLayoutTests = append(funcLayoutTests, funcLayoutTest{ ValueOf(uintptr(0)).Type(), ValueOf(func(a uintptr) {}).Type(), 2 * PtrSize, 2 * PtrSize, 2 * PtrSize, []byte{1}, []byte{1}, // Note: this one is tricky, as the receiver is not a pointer. But we // pass the receiver by reference to the autogenerated pointer-receiver // version of the function. }) } func TestFuncLayout(t *testing.T) { for _, lt := range funcLayoutTests { typ, argsize, retOffset, stack, gc, ptrs := FuncLayout(lt.t, lt.rcvr) if typ.Size() != lt.size { t.Errorf("funcLayout(%v, %v).size=%d, want %d", lt.t, lt.rcvr, typ.Size(), lt.size) } if argsize != lt.argsize { t.Errorf("funcLayout(%v, %v).argsize=%d, want %d", lt.t, lt.rcvr, argsize, lt.argsize) } if retOffset != lt.retOffset { t.Errorf("funcLayout(%v, %v).retOffset=%d, want %d", lt.t, lt.rcvr, retOffset, lt.retOffset) } if !bytes.Equal(stack, lt.stack) { t.Errorf("funcLayout(%v, %v).stack=%v, want %v", lt.t, lt.rcvr, stack, lt.stack) } if !bytes.Equal(gc, lt.gc) { t.Errorf("funcLayout(%v, %v).gc=%v, want %v", lt.t, lt.rcvr, gc, lt.gc) } if ptrs && len(stack) == 0 || !ptrs && len(stack) > 0 { t.Errorf("funcLayout(%v, %v) pointers flag=%v, want %v", lt.t, lt.rcvr, ptrs, !ptrs) } } } func verifyGCBits(t *testing.T, typ Type, bits []byte) { heapBits := GCBits(New(typ).Interface()) if !bytes.Equal(heapBits, bits) { t.Errorf("heapBits incorrect for %v\nhave %v\nwant %v", typ, heapBits, bits) } } func verifyGCBitsSlice(t *testing.T, typ Type, cap int, bits []byte) { // Creating a slice causes the runtime to repeat a bitmap, // which exercises a different path from making the compiler // repeat a bitmap for a small array or executing a repeat in // a GC program. val := MakeSlice(typ, 0, cap) data := NewAt(ArrayOf(cap, typ), unsafe.Pointer(val.Pointer())) heapBits := GCBits(data.Interface()) // Repeat the bitmap for the slice size, trimming scalars in // the last element. bits = rep(cap, bits) for len(bits) > 2 && bits[len(bits)-1] == 0 { bits = bits[:len(bits)-1] } if !bytes.Equal(heapBits, bits) { t.Errorf("heapBits incorrect for make(%v, 0, %v)\nhave %v\nwant %v", typ, cap, heapBits, bits) } } func TestGCBits(t *testing.T) { verifyGCBits(t, TypeOf((*byte)(nil)), []byte{1}) // Building blocks for types seen by the compiler (like [2]Xscalar). // The compiler will create the type structures for the derived types, // including their GC metadata. type Xscalar struct{ x uintptr } type Xptr struct{ x *byte } type Xptrscalar struct { *byte uintptr } type Xscalarptr struct { uintptr *byte } type Xbigptrscalar struct { _ [100]*byte _ [100]uintptr } var Tscalar, Tint64, Tptr, Tscalarptr, Tptrscalar, Tbigptrscalar Type { // Building blocks for types constructed by reflect. // This code is in a separate block so that code below // cannot accidentally refer to these. // The compiler must NOT see types derived from these // (for example, [2]Scalar must NOT appear in the program), // or else reflect will use it instead of having to construct one. // The goal is to test the construction. type Scalar struct{ x uintptr } type Ptr struct{ x *byte } type Ptrscalar struct { *byte uintptr } type Scalarptr struct { uintptr *byte } type Bigptrscalar struct { _ [100]*byte _ [100]uintptr } type Int64 int64 Tscalar = TypeOf(Scalar{}) Tint64 = TypeOf(Int64(0)) Tptr = TypeOf(Ptr{}) Tscalarptr = TypeOf(Scalarptr{}) Tptrscalar = TypeOf(Ptrscalar{}) Tbigptrscalar = TypeOf(Bigptrscalar{}) } empty := []byte{} verifyGCBits(t, TypeOf(Xscalar{}), empty) verifyGCBits(t, Tscalar, empty) verifyGCBits(t, TypeOf(Xptr{}), lit(1)) verifyGCBits(t, Tptr, lit(1)) verifyGCBits(t, TypeOf(Xscalarptr{}), lit(0, 1)) verifyGCBits(t, Tscalarptr, lit(0, 1)) verifyGCBits(t, TypeOf(Xptrscalar{}), lit(1)) verifyGCBits(t, Tptrscalar, lit(1)) verifyGCBits(t, TypeOf([0]Xptr{}), empty) verifyGCBits(t, ArrayOf(0, Tptr), empty) verifyGCBits(t, TypeOf([1]Xptrscalar{}), lit(1)) verifyGCBits(t, ArrayOf(1, Tptrscalar), lit(1)) verifyGCBits(t, TypeOf([2]Xscalar{}), empty) verifyGCBits(t, ArrayOf(2, Tscalar), empty) verifyGCBits(t, TypeOf([10000]Xscalar{}), empty) verifyGCBits(t, ArrayOf(10000, Tscalar), empty) verifyGCBits(t, TypeOf([2]Xptr{}), lit(1, 1)) verifyGCBits(t, ArrayOf(2, Tptr), lit(1, 1)) verifyGCBits(t, TypeOf([10000]Xptr{}), rep(10000, lit(1))) verifyGCBits(t, ArrayOf(10000, Tptr), rep(10000, lit(1))) verifyGCBits(t, TypeOf([2]Xscalarptr{}), lit(0, 1, 0, 1)) verifyGCBits(t, ArrayOf(2, Tscalarptr), lit(0, 1, 0, 1)) verifyGCBits(t, TypeOf([10000]Xscalarptr{}), rep(10000, lit(0, 1))) verifyGCBits(t, ArrayOf(10000, Tscalarptr), rep(10000, lit(0, 1))) verifyGCBits(t, TypeOf([2]Xptrscalar{}), lit(1, 0, 1)) verifyGCBits(t, ArrayOf(2, Tptrscalar), lit(1, 0, 1)) verifyGCBits(t, TypeOf([10000]Xptrscalar{}), rep(10000, lit(1, 0))) verifyGCBits(t, ArrayOf(10000, Tptrscalar), rep(10000, lit(1, 0))) verifyGCBits(t, TypeOf([1][10000]Xptrscalar{}), rep(10000, lit(1, 0))) verifyGCBits(t, ArrayOf(1, ArrayOf(10000, Tptrscalar)), rep(10000, lit(1, 0))) verifyGCBits(t, TypeOf([2][10000]Xptrscalar{}), rep(2*10000, lit(1, 0))) verifyGCBits(t, ArrayOf(2, ArrayOf(10000, Tptrscalar)), rep(2*10000, lit(1, 0))) verifyGCBits(t, TypeOf([4]Xbigptrscalar{}), join(rep(3, join(rep(100, lit(1)), rep(100, lit(0)))), rep(100, lit(1)))) verifyGCBits(t, ArrayOf(4, Tbigptrscalar), join(rep(3, join(rep(100, lit(1)), rep(100, lit(0)))), rep(100, lit(1)))) verifyGCBitsSlice(t, TypeOf([]Xptr{}), 0, empty) verifyGCBitsSlice(t, SliceOf(Tptr), 0, empty) verifyGCBitsSlice(t, TypeOf([]Xptrscalar{}), 1, lit(1)) verifyGCBitsSlice(t, SliceOf(Tptrscalar), 1, lit(1)) verifyGCBitsSlice(t, TypeOf([]Xscalar{}), 2, lit(0)) verifyGCBitsSlice(t, SliceOf(Tscalar), 2, lit(0)) verifyGCBitsSlice(t, TypeOf([]Xscalar{}), 10000, lit(0)) verifyGCBitsSlice(t, SliceOf(Tscalar), 10000, lit(0)) verifyGCBitsSlice(t, TypeOf([]Xptr{}), 2, lit(1)) verifyGCBitsSlice(t, SliceOf(Tptr), 2, lit(1)) verifyGCBitsSlice(t, TypeOf([]Xptr{}), 10000, lit(1)) verifyGCBitsSlice(t, SliceOf(Tptr), 10000, lit(1)) verifyGCBitsSlice(t, TypeOf([]Xscalarptr{}), 2, lit(0, 1)) verifyGCBitsSlice(t, SliceOf(Tscalarptr), 2, lit(0, 1)) verifyGCBitsSlice(t, TypeOf([]Xscalarptr{}), 10000, lit(0, 1)) verifyGCBitsSlice(t, SliceOf(Tscalarptr), 10000, lit(0, 1)) verifyGCBitsSlice(t, TypeOf([]Xptrscalar{}), 2, lit(1, 0)) verifyGCBitsSlice(t, SliceOf(Tptrscalar), 2, lit(1, 0)) verifyGCBitsSlice(t, TypeOf([]Xptrscalar{}), 10000, lit(1, 0)) verifyGCBitsSlice(t, SliceOf(Tptrscalar), 10000, lit(1, 0)) verifyGCBitsSlice(t, TypeOf([][10000]Xptrscalar{}), 1, rep(10000, lit(1, 0))) verifyGCBitsSlice(t, SliceOf(ArrayOf(10000, Tptrscalar)), 1, rep(10000, lit(1, 0))) verifyGCBitsSlice(t, TypeOf([][10000]Xptrscalar{}), 2, rep(10000, lit(1, 0))) verifyGCBitsSlice(t, SliceOf(ArrayOf(10000, Tptrscalar)), 2, rep(10000, lit(1, 0))) verifyGCBitsSlice(t, TypeOf([]Xbigptrscalar{}), 4, join(rep(100, lit(1)), rep(100, lit(0)))) verifyGCBitsSlice(t, SliceOf(Tbigptrscalar), 4, join(rep(100, lit(1)), rep(100, lit(0)))) verifyGCBits(t, TypeOf((chan [100]Xscalar)(nil)), lit(1)) verifyGCBits(t, ChanOf(BothDir, ArrayOf(100, Tscalar)), lit(1)) verifyGCBits(t, TypeOf((func([10000]Xscalarptr))(nil)), lit(1)) verifyGCBits(t, FuncOf([]Type{ArrayOf(10000, Tscalarptr)}, nil, false), lit(1)) verifyGCBits(t, TypeOf((map[[10000]Xscalarptr]Xscalar)(nil)), lit(1)) verifyGCBits(t, MapOf(ArrayOf(10000, Tscalarptr), Tscalar), lit(1)) verifyGCBits(t, TypeOf((*[10000]Xscalar)(nil)), lit(1)) verifyGCBits(t, PtrTo(ArrayOf(10000, Tscalar)), lit(1)) verifyGCBits(t, TypeOf(([][10000]Xscalar)(nil)), lit(1)) verifyGCBits(t, SliceOf(ArrayOf(10000, Tscalar)), lit(1)) hdr := make([]byte, 8/PtrSize) verifyMapBucket := func(t *testing.T, k, e Type, m interface{}, want []byte) { verifyGCBits(t, MapBucketOf(k, e), want) verifyGCBits(t, CachedBucketOf(TypeOf(m)), want) } verifyMapBucket(t, Tscalar, Tptr, map[Xscalar]Xptr(nil), join(hdr, rep(8, lit(0)), rep(8, lit(1)), lit(1))) verifyMapBucket(t, Tscalarptr, Tptr, map[Xscalarptr]Xptr(nil), join(hdr, rep(8, lit(0, 1)), rep(8, lit(1)), lit(1))) verifyMapBucket(t, Tint64, Tptr, map[int64]Xptr(nil), join(hdr, rep(8, rep(8/PtrSize, lit(0))), rep(8, lit(1)), naclpad(), lit(1))) verifyMapBucket(t, Tscalar, Tscalar, map[Xscalar]Xscalar(nil), empty) verifyMapBucket(t, ArrayOf(2, Tscalarptr), ArrayOf(3, Tptrscalar), map[[2]Xscalarptr][3]Xptrscalar(nil), join(hdr, rep(8*2, lit(0, 1)), rep(8*3, lit(1, 0)), lit(1))) verifyMapBucket(t, ArrayOf(64/PtrSize, Tscalarptr), ArrayOf(64/PtrSize, Tptrscalar), map[[64 / PtrSize]Xscalarptr][64 / PtrSize]Xptrscalar(nil), join(hdr, rep(8*64/PtrSize, lit(0, 1)), rep(8*64/PtrSize, lit(1, 0)), lit(1))) verifyMapBucket(t, ArrayOf(64/PtrSize+1, Tscalarptr), ArrayOf(64/PtrSize, Tptrscalar), map[[64/PtrSize + 1]Xscalarptr][64 / PtrSize]Xptrscalar(nil), join(hdr, rep(8, lit(1)), rep(8*64/PtrSize, lit(1, 0)), lit(1))) verifyMapBucket(t, ArrayOf(64/PtrSize, Tscalarptr), ArrayOf(64/PtrSize+1, Tptrscalar), map[[64 / PtrSize]Xscalarptr][64/PtrSize + 1]Xptrscalar(nil), join(hdr, rep(8*64/PtrSize, lit(0, 1)), rep(8, lit(1)), lit(1))) verifyMapBucket(t, ArrayOf(64/PtrSize+1, Tscalarptr), ArrayOf(64/PtrSize+1, Tptrscalar), map[[64/PtrSize + 1]Xscalarptr][64/PtrSize + 1]Xptrscalar(nil), join(hdr, rep(8, lit(1)), rep(8, lit(1)), lit(1))) } func naclpad() []byte { if runtime.GOARCH == "amd64p32" { return lit(0) } return nil } func rep(n int, b []byte) []byte { return bytes.Repeat(b, n) } func join(b ...[]byte) []byte { return bytes.Join(b, nil) } func lit(x ...byte) []byte { return x } func TestTypeOfTypeOf(t *testing.T) { // Check that all the type constructors return concrete *rtype implementations. // It's difficult to test directly because the reflect package is only at arm's length. // The easiest thing to do is just call a function that crashes if it doesn't get an *rtype. check := func(name string, typ Type) { if underlying := TypeOf(typ).String(); underlying != "*reflect.rtype" { t.Errorf("%v returned %v, not *reflect.rtype", name, underlying) } } type T struct{ int } check("TypeOf", TypeOf(T{})) check("ArrayOf", ArrayOf(10, TypeOf(T{}))) check("ChanOf", ChanOf(BothDir, TypeOf(T{}))) check("FuncOf", FuncOf([]Type{TypeOf(T{})}, nil, false)) check("MapOf", MapOf(TypeOf(T{}), TypeOf(T{}))) check("PtrTo", PtrTo(TypeOf(T{}))) check("SliceOf", SliceOf(TypeOf(T{}))) } type XM struct{} func (*XM) String() string { return "" } func TestPtrToMethods(t *testing.T) { var y struct{ XM } yp := New(TypeOf(y)).Interface() _, ok := yp.(fmt.Stringer) if !ok { t.Fatal("does not implement Stringer, but should") } }