| 1 | package main |
|---|---|
| 2 | |
| 3 | // Tests of composite literals. |
| 4 | |
| 5 | import "fmt" |
| 6 | |
| 7 | // Map literals. |
| 8 | // TODO(adonovan): we can no longer print maps |
| 9 | // until the interpreter supports (reflect.Value).MapRange. |
| 10 | func _() { |
| 11 | type M map[int]int |
| 12 | m1 := []*M{{1: 1}, &M{2: 2}} |
| 13 | want := "map[1:1] map[2:2]" |
| 14 | if got := fmt.Sprint(*m1[0], *m1[1]); got != want { |
| 15 | panic(got) |
| 16 | } |
| 17 | m2 := []M{{1: 1}, M{2: 2}} |
| 18 | if got := fmt.Sprint(m2[0], m2[1]); got != want { |
| 19 | panic(got) |
| 20 | } |
| 21 | } |
| 22 | |
| 23 | // Nonliteral keys in composite literal. |
| 24 | func init() { |
| 25 | const zero int = 1 |
| 26 | var v = []int{1 + zero: 42} |
| 27 | if x := fmt.Sprint(v); x != "[0 0 42]" { |
| 28 | panic(x) |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | // Test for in-place initialization. |
| 33 | func init() { |
| 34 | // struct |
| 35 | type S struct { |
| 36 | a, b int |
| 37 | } |
| 38 | s := S{1, 2} |
| 39 | s = S{b: 3} |
| 40 | if s.a != 0 { |
| 41 | panic("s.a != 0") |
| 42 | } |
| 43 | if s.b != 3 { |
| 44 | panic("s.b != 3") |
| 45 | } |
| 46 | s = S{} |
| 47 | if s.a != 0 { |
| 48 | panic("s.a != 0") |
| 49 | } |
| 50 | if s.b != 0 { |
| 51 | panic("s.b != 0") |
| 52 | } |
| 53 | |
| 54 | // array |
| 55 | type A [4]int |
| 56 | a := A{2, 4, 6, 8} |
| 57 | a = A{1: 6, 2: 4} |
| 58 | if a[0] != 0 { |
| 59 | panic("a[0] != 0") |
| 60 | } |
| 61 | if a[1] != 6 { |
| 62 | panic("a[1] != 6") |
| 63 | } |
| 64 | if a[2] != 4 { |
| 65 | panic("a[2] != 4") |
| 66 | } |
| 67 | if a[3] != 0 { |
| 68 | panic("a[3] != 0") |
| 69 | } |
| 70 | a = A{} |
| 71 | if a[0] != 0 { |
| 72 | panic("a[0] != 0") |
| 73 | } |
| 74 | if a[1] != 0 { |
| 75 | panic("a[1] != 0") |
| 76 | } |
| 77 | if a[2] != 0 { |
| 78 | panic("a[2] != 0") |
| 79 | } |
| 80 | if a[3] != 0 { |
| 81 | panic("a[3] != 0") |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | // Regression test for https://golang.org/issue/10127: |
| 86 | // composite literal clobbers destination before reading from it. |
| 87 | func init() { |
| 88 | // map |
| 89 | { |
| 90 | type M map[string]int |
| 91 | m := M{"x": 1, "y": 2} |
| 92 | m = M{"x": m["y"], "y": m["x"]} |
| 93 | if m["x"] != 2 || m["y"] != 1 { |
| 94 | panic(fmt.Sprint(m)) |
| 95 | } |
| 96 | |
| 97 | n := M{"x": 3} |
| 98 | m, n = M{"x": n["x"]}, M{"x": m["x"]} // parallel assignment |
| 99 | if got := fmt.Sprint(m["x"], n["x"]); got != "3 2" { |
| 100 | panic(got) |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | // struct |
| 105 | { |
| 106 | type T struct{ x, y, z int } |
| 107 | t := T{x: 1, y: 2, z: 3} |
| 108 | |
| 109 | t = T{x: t.y, y: t.z, z: t.x} // all fields |
| 110 | if got := fmt.Sprint(t); got != "{2 3 1}" { |
| 111 | panic(got) |
| 112 | } |
| 113 | |
| 114 | t = T{x: t.y, y: t.z + 3} // not all fields |
| 115 | if got := fmt.Sprint(t); got != "{3 4 0}" { |
| 116 | panic(got) |
| 117 | } |
| 118 | |
| 119 | u := T{x: 5, y: 6, z: 7} |
| 120 | t, u = T{x: u.x}, T{x: t.x} // parallel assignment |
| 121 | if got := fmt.Sprint(t, u); got != "{5 0 0} {3 0 0}" { |
| 122 | panic(got) |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | // array |
| 127 | { |
| 128 | a := [3]int{0: 1, 1: 2, 2: 3} |
| 129 | |
| 130 | a = [3]int{0: a[1], 1: a[2], 2: a[0]} // all elements |
| 131 | if got := fmt.Sprint(a); got != "[2 3 1]" { |
| 132 | panic(got) |
| 133 | } |
| 134 | |
| 135 | a = [3]int{0: a[1], 1: a[2] + 3} // not all elements |
| 136 | if got := fmt.Sprint(a); got != "[3 4 0]" { |
| 137 | panic(got) |
| 138 | } |
| 139 | |
| 140 | b := [3]int{0: 5, 1: 6, 2: 7} |
| 141 | a, b = [3]int{0: b[0]}, [3]int{0: a[0]} // parallel assignment |
| 142 | if got := fmt.Sprint(a, b); got != "[5 0 0] [3 0 0]" { |
| 143 | panic(got) |
| 144 | } |
| 145 | } |
| 146 | |
| 147 | // slice |
| 148 | { |
| 149 | s := []int{0: 1, 1: 2, 2: 3} |
| 150 | |
| 151 | s = []int{0: s[1], 1: s[2], 2: s[0]} // all elements |
| 152 | if got := fmt.Sprint(s); got != "[2 3 1]" { |
| 153 | panic(got) |
| 154 | } |
| 155 | |
| 156 | s = []int{0: s[1], 1: s[2] + 3} // not all elements |
| 157 | if got := fmt.Sprint(s); got != "[3 4]" { |
| 158 | panic(got) |
| 159 | } |
| 160 | |
| 161 | t := []int{0: 5, 1: 6, 2: 7} |
| 162 | s, t = []int{0: t[0]}, []int{0: s[0]} // parallel assignment |
| 163 | if got := fmt.Sprint(s, t); got != "[5] [3]" { |
| 164 | panic(got) |
| 165 | } |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | // Regression test for https://golang.org/issue/13341: |
| 170 | // within a map literal, if a key expression is a composite literal, |
| 171 | // Go 1.5 allows its type to be omitted. An & operation may be implied. |
| 172 | func init() { |
| 173 | type S struct{ x int } |
| 174 | // same as map[*S]bool{&S{x: 1}: true} |
| 175 | m := map[*S]bool{{x: 1}: true} |
| 176 | for s := range m { |
| 177 | if s.x != 1 { |
| 178 | panic(s) // wrong key |
| 179 | } |
| 180 | return |
| 181 | } |
| 182 | panic("map is empty") |
| 183 | } |
| 184 | |
| 185 | func main() { |
| 186 | } |
| 187 |
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