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go/pointer/testdata/mapreflect.go
Alan Donovan 94c387c610 go.tools/pointer: implement (reflect.Value).Call.
The implementation follows the basic pattern of an indirect
function call (genDynamicCall).

We use the same trick as SetFinalizer so that direct calls to
(r.V).Call, which are overwhelmingly the norm, are inlined.

Bug fix (and simplification): calling untag() to unbox a
reflect.Value is wrong for reflect.Values containing interfaces
(rare).  Now, we call untag for concrete types and typeFilter
for interface types, and we can use this pattern in all cases.
It corresponds to the ssa.TypeAssert operator, so we call
it typeAssert.  Added tests to cover this.

We also specialize reflect.{In,Out} when the operand is an int
literal.

+ Tests.

Also:
- make taggedValue() panic, not return nil, eliminating many checks.
  We call isTaggedValue for the one place that cares.
- pointer_test: recover from panics in Analyze() and dump the log.

R=crawshaw
CC=golang-dev
https://golang.org/cl/14426050
2013-10-29 21:57:53 -04:00

118 lines
3.7 KiB
Go

// +build ignore
package main
// Test of maps with reflection.
import "reflect"
var a int
var b bool
func reflectMapKeysIndex() {
m := make(map[*int]*bool) // @line mr1make
m[&a] = &b
mrv := reflect.ValueOf(m)
print(mrv.Interface()) // @types map[*int]*bool
print(mrv.Interface().(map[*int]*bool)) // @pointsto makemap@mr1make:11
print(mrv) // @pointsto makeinterface:map[*int]*bool
print(mrv) // @types map[*int]*bool
keys := mrv.MapKeys()
print(keys) // @pointsto <alloc in (reflect.Value).MapKeys>
for _, k := range keys {
print(k) // @pointsto <alloc in (reflect.Value).MapKeys>
print(k) // @types *int
print(k.Interface()) // @types *int
print(k.Interface().(*int)) // @pointsto main.a
v := mrv.MapIndex(k)
print(v.Interface()) // @types *bool
print(v.Interface().(*bool)) // @pointsto main.b
}
}
func reflectSetMapIndex() {
m := make(map[*int]*bool)
mrv := reflect.ValueOf(m)
mrv.SetMapIndex(reflect.ValueOf(&a), reflect.ValueOf(&b))
print(m[nil]) // @pointsto main.b
for _, k := range mrv.MapKeys() {
print(k.Interface()) // @types *int
print(k.Interface().(*int)) // @pointsto main.a
}
tmap := reflect.TypeOf(m)
// types.EvalNode won't let us refer to non-exported types:
// print(tmap) // #@types *reflect.rtype
print(tmap) // @pointsto map[*int]*bool
zmap := reflect.Zero(tmap)
print(zmap) // @pointsto <alloc in reflect.Zero>
print(zmap.Interface()) // @pointsto <alloc in reflect.Zero>
print(tmap.Key()) // @pointsto *int
print(tmap.Elem()) // @pointsto *bool
print(reflect.Zero(tmap.Key())) // @pointsto <alloc in reflect.Zero>
print(reflect.Zero(tmap.Key()).Interface()) // @pointsto <alloc in reflect.Zero>
print(reflect.Zero(tmap.Key()).Interface()) // @types *int
print(reflect.Zero(tmap.Elem())) // @pointsto <alloc in reflect.Zero>
print(reflect.Zero(tmap.Elem()).Interface()) // @pointsto <alloc in reflect.Zero>
print(reflect.Zero(tmap.Elem()).Interface()) // @types *bool
}
func reflectSetMapIndexInterface() {
// Exercises reflect.Value conversions to/from interfaces:
// a different code path than for concrete types.
m := make(map[interface{}]interface{})
reflect.ValueOf(m).SetMapIndex(reflect.ValueOf(&a), reflect.ValueOf(&b))
for k, v := range m {
print(k) // @types *int
print(k.(*int)) // @pointsto main.a
print(v) // @types *bool
print(v.(*bool)) // @pointsto main.b
}
}
func reflectSetMapIndexAssignable() {
// SetMapIndex performs implicit assignability conversions.
type I *int
type J *int
str := reflect.ValueOf("")
// *int is assignable to I.
m1 := make(map[string]I)
reflect.ValueOf(m1).SetMapIndex(str, reflect.ValueOf(new(int))) // @line int
print(m1[""]) // @pointsto new@int:58
// I is assignable to I.
m2 := make(map[string]I)
reflect.ValueOf(m2).SetMapIndex(str, reflect.ValueOf(I(new(int)))) // @line I
print(m2[""]) // @pointsto new@I:60
// J is not assignable to I.
m3 := make(map[string]I)
reflect.ValueOf(m3).SetMapIndex(str, reflect.ValueOf(J(new(int))))
print(m3[""]) // @pointsto
}
func reflectMakeMap() {
t := reflect.TypeOf(map[*int]*bool(nil))
v := reflect.MakeMap(t)
print(v) // @types map[*int]*bool
print(v) // @pointsto <alloc in reflect.MakeMap>
}
func main() {
reflectMapKeysIndex()
reflectSetMapIndex()
reflectSetMapIndexInterface()
reflectSetMapIndexAssignable()
reflectMakeMap()
// TODO(adonovan): reflect.MapOf(Type)
}