1 // Copyright 2011 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package reflect_test 6 7 import ( 8 "bytes" 9 "go/ast" 10 "go/token" 11 "io" 12 . "reflect" 13 "testing" 14 "unsafe" 15 ) 16 17 type MyBuffer bytes.Buffer 18 19 func TestImplicitMapConversion(t *testing.T) { 20 // Test implicit conversions in MapIndex and SetMapIndex. 21 { 22 // direct 23 m := make(map[int]int) 24 mv := ValueOf(m) 25 mv.SetMapIndex(ValueOf(1), ValueOf(2)) 26 x, ok := m[1] 27 if x != 2 { 28 t.Errorf("#1 after SetMapIndex(1,2): %d, %t (map=%v)", x, ok, m) 29 } 30 if n := mv.MapIndex(ValueOf(1)).Interface().(int); n != 2 { 31 t.Errorf("#1 MapIndex(1) = %d", n) 32 } 33 } 34 { 35 // convert interface key 36 m := make(map[interface{}]int) 37 mv := ValueOf(m) 38 mv.SetMapIndex(ValueOf(1), ValueOf(2)) 39 x, ok := m[1] 40 if x != 2 { 41 t.Errorf("#2 after SetMapIndex(1,2): %d, %t (map=%v)", x, ok, m) 42 } 43 if n := mv.MapIndex(ValueOf(1)).Interface().(int); n != 2 { 44 t.Errorf("#2 MapIndex(1) = %d", n) 45 } 46 } 47 { 48 // convert interface value 49 m := make(map[int]interface{}) 50 mv := ValueOf(m) 51 mv.SetMapIndex(ValueOf(1), ValueOf(2)) 52 x, ok := m[1] 53 if x != 2 { 54 t.Errorf("#3 after SetMapIndex(1,2): %d, %t (map=%v)", x, ok, m) 55 } 56 if n := mv.MapIndex(ValueOf(1)).Interface().(int); n != 2 { 57 t.Errorf("#3 MapIndex(1) = %d", n) 58 } 59 } 60 { 61 // convert both interface key and interface value 62 m := make(map[interface{}]interface{}) 63 mv := ValueOf(m) 64 mv.SetMapIndex(ValueOf(1), ValueOf(2)) 65 x, ok := m[1] 66 if x != 2 { 67 t.Errorf("#4 after SetMapIndex(1,2): %d, %t (map=%v)", x, ok, m) 68 } 69 if n := mv.MapIndex(ValueOf(1)).Interface().(int); n != 2 { 70 t.Errorf("#4 MapIndex(1) = %d", n) 71 } 72 } 73 { 74 // convert both, with non-empty interfaces 75 m := make(map[io.Reader]io.Writer) 76 mv := ValueOf(m) 77 b1 := new(bytes.Buffer) 78 b2 := new(bytes.Buffer) 79 mv.SetMapIndex(ValueOf(b1), ValueOf(b2)) 80 x, ok := m[b1] 81 if x != b2 { 82 t.Errorf("#5 after SetMapIndex(b1, b2): %p (!= %p), %t (map=%v)", x, b2, ok, m) 83 } 84 if p := mv.MapIndex(ValueOf(b1)).Elem().Pointer(); p != uintptr(unsafe.Pointer(b2)) { 85 t.Errorf("#5 MapIndex(b1) = %#x want %p", p, b2) 86 } 87 } 88 { 89 // convert channel direction 90 m := make(map[<-chan int]chan int) 91 mv := ValueOf(m) 92 c1 := make(chan int) 93 c2 := make(chan int) 94 mv.SetMapIndex(ValueOf(c1), ValueOf(c2)) 95 x, ok := m[c1] 96 if x != c2 { 97 t.Errorf("#6 after SetMapIndex(c1, c2): %p (!= %p), %t (map=%v)", x, c2, ok, m) 98 } 99 if p := mv.MapIndex(ValueOf(c1)).Pointer(); p != ValueOf(c2).Pointer() { 100 t.Errorf("#6 MapIndex(c1) = %#x want %p", p, c2) 101 } 102 } 103 { 104 // convert identical underlying types 105 // TODO(rsc): Should be able to define MyBuffer here. 106 // 6l prints very strange messages about .this.Bytes etc 107 // when we do that though, so MyBuffer is defined 108 // at top level. 109 m := make(map[*MyBuffer]*bytes.Buffer) 110 mv := ValueOf(m) 111 b1 := new(MyBuffer) 112 b2 := new(bytes.Buffer) 113 mv.SetMapIndex(ValueOf(b1), ValueOf(b2)) 114 x, ok := m[b1] 115 if x != b2 { 116 t.Errorf("#7 after SetMapIndex(b1, b2): %p (!= %p), %t (map=%v)", x, b2, ok, m) 117 } 118 if p := mv.MapIndex(ValueOf(b1)).Pointer(); p != uintptr(unsafe.Pointer(b2)) { 119 t.Errorf("#7 MapIndex(b1) = %#x want %p", p, b2) 120 } 121 } 122 123 } 124 125 func TestImplicitSetConversion(t *testing.T) { 126 // Assume TestImplicitMapConversion covered the basics. 127 // Just make sure conversions are being applied at all. 128 var r io.Reader 129 b := new(bytes.Buffer) 130 rv := ValueOf(&r).Elem() 131 rv.Set(ValueOf(b)) 132 if r != b { 133 t.Errorf("after Set: r=%T(%v)", r, r) 134 } 135 } 136 137 func TestImplicitSendConversion(t *testing.T) { 138 c := make(chan io.Reader, 10) 139 b := new(bytes.Buffer) 140 ValueOf(c).Send(ValueOf(b)) 141 if bb := <-c; bb != b { 142 t.Errorf("Received %p != %p", bb, b) 143 } 144 } 145 146 func TestImplicitCallConversion(t *testing.T) { 147 // Arguments must be assignable to parameter types. 148 fv := ValueOf(io.WriteString) 149 b := new(bytes.Buffer) 150 fv.Call([]Value{ValueOf(b), ValueOf("hello world")}) 151 if b.String() != "hello world" { 152 t.Errorf("After call: string=%q want %q", b.String(), "hello world") 153 } 154 } 155 156 func TestImplicitAppendConversion(t *testing.T) { 157 // Arguments must be assignable to the slice's element type. 158 s := []io.Reader{} 159 sv := ValueOf(&s).Elem() 160 b := new(bytes.Buffer) 161 sv.Set(Append(sv, ValueOf(b))) 162 if len(s) != 1 || s[0] != b { 163 t.Errorf("after append: s=%v want [%p]", s, b) 164 } 165 } 166 167 var implementsTests = []struct { 168 x interface{} 169 t interface{} 170 b bool 171 }{ 172 {new(*bytes.Buffer), new(io.Reader), true}, 173 {new(bytes.Buffer), new(io.Reader), false}, 174 {new(*bytes.Buffer), new(io.ReaderAt), false}, 175 {new(*ast.Ident), new(ast.Expr), true}, 176 {new(*notAnExpr), new(ast.Expr), false}, 177 {new(*ast.Ident), new(notASTExpr), false}, 178 {new(notASTExpr), new(ast.Expr), false}, 179 {new(ast.Expr), new(notASTExpr), false}, 180 {new(*notAnExpr), new(notASTExpr), true}, 181 } 182 183 type notAnExpr struct{} 184 185 func (notAnExpr) Pos() token.Pos { return token.NoPos } 186 func (notAnExpr) End() token.Pos { return token.NoPos } 187 func (notAnExpr) exprNode() {} 188 189 type notASTExpr interface { 190 Pos() token.Pos 191 End() token.Pos 192 exprNode() 193 } 194 195 func TestImplements(t *testing.T) { 196 for _, tt := range implementsTests { 197 xv := TypeOf(tt.x).Elem() 198 xt := TypeOf(tt.t).Elem() 199 if b := xv.Implements(xt); b != tt.b { 200 t.Errorf("(%s).Implements(%s) = %v, want %v", xv.String(), xt.String(), b, tt.b) 201 } 202 } 203 } 204 205 var assignableTests = []struct { 206 x interface{} 207 t interface{} 208 b bool 209 }{ 210 {new(chan int), new(<-chan int), true}, 211 {new(<-chan int), new(chan int), false}, 212 {new(*int), new(IntPtr), true}, 213 {new(IntPtr), new(*int), true}, 214 {new(IntPtr), new(IntPtr1), false}, 215 {new(Ch), new(<-chan interface{}), true}, 216 // test runs implementsTests too 217 } 218 219 type IntPtr *int 220 type IntPtr1 *int 221 type Ch <-chan interface{} 222 223 func TestAssignableTo(t *testing.T) { 224 for _, tt := range append(assignableTests, implementsTests...) { 225 xv := TypeOf(tt.x).Elem() 226 xt := TypeOf(tt.t).Elem() 227 if b := xv.AssignableTo(xt); b != tt.b { 228 t.Errorf("(%s).AssignableTo(%s) = %v, want %v", xv.String(), xt.String(), b, tt.b) 229 } 230 } 231 } 232
