gopls/go/pointer/testdata/mapreflect.go

1	//go:build ignore
2	// +build ignore
3
4	package main
5
6	// Test of maps with reflection.
7
8	import "reflect"
9
10	var a int
11	var b bool
12
13	func reflectMapKeysIndex() {
14	m := make(map[int]bool) // @line mr1make
15	m[&a] = &b
16
17	mrv := reflect.ValueOf(m)
18	print(mrv.Interface()) // @types map[int]bool
19	print(mrv.Interface().(map[int]bool)) // @pointsto makemap@mr1make:11
20	print(mrv) // @pointsto makeinterface:map[int]bool
21	print(mrv) // @types map[int]bool
22
23	keys := mrv.MapKeys()
24	print(keys) // @pointsto <alloc in (reflect.Value).MapKeys>
25	for _, k := range keys {
26	print(k) // @pointsto <alloc in (reflect.Value).MapKeys>
27	print(k) // @types *int
28	print(k.Interface()) // @types *int
29	print(k.Interface().(*int)) // @pointsto command-line-arguments.a
30
31	v := mrv.MapIndex(k)
32	print(v.Interface()) // @types *bool
33	print(v.Interface().(*bool)) // @pointsto command-line-arguments.b
34	}
35	}
36
37	func reflectSetMapIndex() {
38	m := make(map[int]bool)
39	mrv := reflect.ValueOf(m)
40	mrv.SetMapIndex(reflect.ValueOf(&a), reflect.ValueOf(&b))
41
42	print(m[nil]) // @pointsto command-line-arguments.b
43
44	for _, k := range mrv.MapKeys() {
45	print(k.Interface()) // @types *int
46	print(k.Interface().(*int)) // @pointsto command-line-arguments.a
47	}
48
49	tmap := reflect.TypeOf(m)
50	// types.EvalNode won't let us refer to non-exported types:
51	// print(tmap) // #@types *reflect.rtype
52	print(tmap) // @pointsto map[int]bool
53
54	zmap := reflect.Zero(tmap)
55	print(zmap) // @pointsto <alloc in reflect.Zero>
56	print(zmap.Interface()) // @pointsto <alloc in reflect.Zero>
57
58	print(tmap.Key()) // @pointsto *int
59	print(tmap.Elem()) // @pointsto *bool
60	print(reflect.Zero(tmap.Key())) // @pointsto <alloc in reflect.Zero>
61	print(reflect.Zero(tmap.Key()).Interface()) // @pointsto <alloc in reflect.Zero>
62	print(reflect.Zero(tmap.Key()).Interface()) // @types *int
63	print(reflect.Zero(tmap.Elem())) // @pointsto <alloc in reflect.Zero>
64	print(reflect.Zero(tmap.Elem()).Interface()) // @pointsto <alloc in reflect.Zero>
65	print(reflect.Zero(tmap.Elem()).Interface()) // @types *bool
66	}
67
68	func reflectSetMapIndexInterface() {
69	// Exercises reflect.Value conversions to/from interfaces:
70	// a different code path than for concrete types.
71	m := make(map[interface{}]interface{})
72	reflect.ValueOf(m).SetMapIndex(reflect.ValueOf(&a), reflect.ValueOf(&b))
73	for k, v := range m {
74	print(k) // @types *int
75	print(k.(*int)) // @pointsto command-line-arguments.a
76	print(v) // @types *bool
77	print(v.(*bool)) // @pointsto command-line-arguments.b
78	}
79	}
80
81	func reflectSetMapIndexAssignable() {
82	// SetMapIndex performs implicit assignability conversions.
83	type I *int
84	type J *int
85
86	str := reflect.ValueOf("")
87
88	// *int is assignable to I.
89	m1 := make(map[string]I)
90	reflect.ValueOf(m1).SetMapIndex(str, reflect.ValueOf(new(int))) // @line int
91	print(m1[""]) // @pointsto new@int:58
92
93	// I is assignable to I.
94	m2 := make(map[string]I)
95	reflect.ValueOf(m2).SetMapIndex(str, reflect.ValueOf(I(new(int)))) // @line I
96	print(m2[""]) // @pointsto new@I:60
97
98	// J is not assignable to I.
99	m3 := make(map[string]I)
100	reflect.ValueOf(m3).SetMapIndex(str, reflect.ValueOf(J(new(int))))
101	print(m3[""]) // @pointsto
102	}
103
104	func reflectMakeMap() {
105	t := reflect.TypeOf(map[int]bool(nil))
106	v := reflect.MakeMap(t)
107	print(v) // @types map[int]bool
108	print(v) // @pointsto <alloc in reflect.MakeMap>
109	}
110
111	func main() {
112	reflectMapKeysIndex()
113	reflectSetMapIndex()
114	reflectSetMapIndexInterface()
115	reflectSetMapIndexAssignable()
116	reflectMakeMap()
117	// TODO(adonovan): reflect.MapOf(Type)
118	}
119

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