| 1 | //go:build ignore |
|---|---|
| 2 | // +build ignore |
| 3 | |
| 4 | package main |
| 5 | |
| 6 | type I interface { |
| 7 | f() |
| 8 | } |
| 9 | |
| 10 | type C int |
| 11 | |
| 12 | func (*C) f() {} |
| 13 | |
| 14 | type D struct{ ptr *int } |
| 15 | |
| 16 | func (D) f() {} |
| 17 | |
| 18 | type E struct{} |
| 19 | |
| 20 | func (*E) f() {} |
| 21 | |
| 22 | var a, b int |
| 23 | |
| 24 | var unknown bool // defeat dead-code elimination |
| 25 | |
| 26 | func interface1() { |
| 27 | var i interface{} = &a |
| 28 | var j interface{} = D{&b} |
| 29 | k := j |
| 30 | if unknown { |
| 31 | k = i |
| 32 | } |
| 33 | |
| 34 | print(i) // @types *int |
| 35 | print(j) // @types D |
| 36 | print(k) // @types *int | D |
| 37 | |
| 38 | print(i.(*int)) // @pointsto command-line-arguments.a |
| 39 | print(j.(*int)) // @pointsto |
| 40 | print(k.(*int)) // @pointsto command-line-arguments.a |
| 41 | |
| 42 | print(i.(D).ptr) // @pointsto |
| 43 | print(j.(D).ptr) // @pointsto command-line-arguments.b |
| 44 | print(k.(D).ptr) // @pointsto command-line-arguments.b |
| 45 | } |
| 46 | |
| 47 | func interface2() { |
| 48 | var i I = (*C)(&a) |
| 49 | var j I = D{&a} |
| 50 | k := j |
| 51 | if unknown { |
| 52 | k = i |
| 53 | } |
| 54 | |
| 55 | print(i) // @types *C |
| 56 | print(j) // @types D |
| 57 | print(k) // @types *C | D |
| 58 | print(k) // @pointsto makeinterface:command-line-arguments.D | makeinterface:*command-line-arguments.C |
| 59 | |
| 60 | k.f() |
| 61 | // @calls command-line-arguments.interface2 -> (*command-line-arguments.C).f |
| 62 | // @calls command-line-arguments.interface2 -> (command-line-arguments.D).f |
| 63 | |
| 64 | print(i.(*C)) // @pointsto command-line-arguments.a |
| 65 | print(j.(D).ptr) // @pointsto command-line-arguments.a |
| 66 | print(k.(*C)) // @pointsto command-line-arguments.a |
| 67 | |
| 68 | switch x := k.(type) { |
| 69 | case *C: |
| 70 | print(x) // @pointsto command-line-arguments.a |
| 71 | case D: |
| 72 | print(x.ptr) // @pointsto command-line-arguments.a |
| 73 | case *E: |
| 74 | print(x) // @pointsto |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | func interface3() { |
| 79 | // There should be no backflow of concrete types from the type-switch to x. |
| 80 | var x interface{} = 0 |
| 81 | print(x) // @types int |
| 82 | switch x.(type) { |
| 83 | case int: |
| 84 | case string: |
| 85 | } |
| 86 | } |
| 87 | |
| 88 | func interface4() { |
| 89 | var i interface{} = D{&a} |
| 90 | if unknown { |
| 91 | i = 123 |
| 92 | } |
| 93 | |
| 94 | print(i) // @types int | D |
| 95 | |
| 96 | j := i.(I) // interface narrowing type-assertion |
| 97 | print(j) // @types D |
| 98 | print(j.(D).ptr) // @pointsto command-line-arguments.a |
| 99 | |
| 100 | var l interface{} = j // interface widening assignment. |
| 101 | print(l) // @types D |
| 102 | print(l.(D).ptr) // @pointsto command-line-arguments.a |
| 103 | |
| 104 | m := j.(interface{}) // interface widening type-assertion. |
| 105 | print(m) // @types D |
| 106 | print(m.(D).ptr) // @pointsto command-line-arguments.a |
| 107 | } |
| 108 | |
| 109 | // Interface method calls and value flow: |
| 110 | |
| 111 | type J interface { |
| 112 | f(*int) *int |
| 113 | } |
| 114 | |
| 115 | type P struct { |
| 116 | x int |
| 117 | } |
| 118 | |
| 119 | func (p *P) f(pi *int) *int { |
| 120 | print(p) // @pointsto p@i5p:6 |
| 121 | print(pi) // @pointsto i@i5i:6 |
| 122 | return &p.x |
| 123 | } |
| 124 | |
| 125 | func interface5() { |
| 126 | var p P // @line i5p |
| 127 | var j J = &p |
| 128 | var i int // @line i5i |
| 129 | print(j.f(&i)) // @pointsto p.x@i5p:6 |
| 130 | print(&i) // @pointsto i@i5i:6 |
| 131 | |
| 132 | print(j) // @pointsto makeinterface:*command-line-arguments.P |
| 133 | } |
| 134 | |
| 135 | // @calls command-line-arguments.interface5 -> (*command-line-arguments.P).f |
| 136 | |
| 137 | func interface6() { |
| 138 | f := I.f |
| 139 | print(f) // @pointsto (command-line-arguments.I).f$thunk |
| 140 | f(new(struct{ D })) |
| 141 | } |
| 142 | |
| 143 | // @calls command-line-arguments.interface6 -> (command-line-arguments.I).f$thunk |
| 144 | // @calls (command-line-arguments.I).f$thunk -> (*struct{command-line-arguments.D}).f |
| 145 | |
| 146 | func main() { |
| 147 | interface1() |
| 148 | interface2() |
| 149 | interface3() |
| 150 | interface4() |
| 151 | interface5() |
| 152 | interface6() |
| 153 | } |
| 154 |
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