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//go:build ignore
// +build ignore
package main
import "reflect"
var zero, a, b int
var false2 bool
func f(p *int, q hasF) *int {
print(p) // @pointsto command-line-arguments.a
print(q) // @types *T
print(q.(*T)) // @pointsto new@newT1:22
return &b
}
func g(p *bool) (*int, *bool, hasF) {
return &b, p, new(T) // @line newT2
}
func reflectValueCall() {
rvf := reflect.ValueOf(f)
res := rvf.Call([]reflect.Value{
// argument order is not significant:
reflect.ValueOf(new(T)), // @line newT1
reflect.ValueOf(&a),
})
print(res[0].Interface()) // @types *int
print(res[0].Interface().(*int)) // @pointsto command-line-arguments.b
}
// @calls command-line-arguments.reflectValueCall -> command-line-arguments.f
func reflectValueCallIndirect() {
rvf := reflect.ValueOf(g)
call := rvf.Call // kids, don't try this at home
// Indirect call uses shared contour.
//
// Also notice that argument position doesn't matter, and args
// of inappropriate type (e.g. 'a') are ignored.
res := call([]reflect.Value{
reflect.ValueOf(&a),
reflect.ValueOf(&false2),
})
res0 := res[0].Interface()
print(res0) // @types *int | *bool | *T
print(res0.(*int)) // @pointsto command-line-arguments.b
print(res0.(*bool)) // @pointsto command-line-arguments.false2
print(res0.(hasF)) // @types *T
print(res0.(*T)) // @pointsto new@newT2:19
}
// @calls command-line-arguments.reflectValueCallIndirect -> (reflect.Value).Call$bound
// @calls (reflect.Value).Call$bound -> command-line-arguments.g
func reflectTypeInOut() {
var f func(float64, bool) (string, int)
print(reflect.Zero(reflect.TypeOf(f).In(0)).Interface()) // @types float64
print(reflect.Zero(reflect.TypeOf(f).In(1)).Interface()) // @types bool
print(reflect.Zero(reflect.TypeOf(f).In(-1)).Interface()) // @types float64 | bool
print(reflect.Zero(reflect.TypeOf(f).In(zero)).Interface()) // @types float64 | bool
print(reflect.Zero(reflect.TypeOf(f).Out(0)).Interface()) // @types string
print(reflect.Zero(reflect.TypeOf(f).Out(1)).Interface()) // @types int
print(reflect.Zero(reflect.TypeOf(f).Out(2)).Interface()) // @types
print(reflect.Zero(reflect.TypeOf(3).Out(0)).Interface()) // @types
}
type hasF interface {
F()
}
type T struct{}
func (T) F() {}
func (T) g(int) {}
type U struct{}
func (U) F(int) {}
func (U) g(string) {}
type I interface {
f()
}
var nonconst string
func reflectTypeMethodByName() {
TU := reflect.TypeOf([]interface{}{T{}, U{}}[0])
print(reflect.Zero(TU)) // @types T | U
F, _ := TU.MethodByName("F")
print(reflect.Zero(F.Type)) // @types func(T) | func(U, int)
print(F.Func) // @pointsto (command-line-arguments.T).F | (command-line-arguments.U).F
g, _ := TU.MethodByName("g")
print(reflect.Zero(g.Type)) // @types func(T, int) | func(U, string)
print(g.Func) // @pointsto (command-line-arguments.T).g | (command-line-arguments.U).g
// Non-literal method names are treated less precisely.
U := reflect.TypeOf(U{})
X, _ := U.MethodByName(nonconst)
print(reflect.Zero(X.Type)) // @types func(U, int) | func(U, string)
print(X.Func) // @pointsto (command-line-arguments.U).F | (command-line-arguments.U).g
// Interface methods.
rThasF := reflect.TypeOf(new(hasF)).Elem()
print(reflect.Zero(rThasF)) // @types hasF
F2, _ := rThasF.MethodByName("F")
print(reflect.Zero(F2.Type)) // @types func()
print(F2.Func) // @pointsto
}
func reflectTypeMethod() {
m := reflect.TypeOf(T{}).Method(0)
print(reflect.Zero(m.Type)) // @types func(T) | func(T, int)
print(m.Func) // @pointsto (command-line-arguments.T).F | (command-line-arguments.T).g
}
func main() {
reflectValueCall()
reflectValueCallIndirect()
reflectTypeInOut()
reflectTypeMethodByName()
reflectTypeMethod()
}
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