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// +build ignore
package main
// Test of arrays & slices with reflection.
import "reflect"
var a, b int
type S string
func reflectValueSlice() {
// reflect.Value contains a slice.
slice := make([]*int, 10) // @line slice
slice[0] = &a
rvsl := reflect.ValueOf(slice).Slice(0, 0)
print(rvsl.Interface()) // @types []*int
print(rvsl.Interface().([]*int)) // @pointsto makeslice@slice:15
print(rvsl.Interface().([]*int)[42]) // @pointsto main.a
// reflect.Value contains an array (non-addressable).
array := [10]*int{&a} // @line array
rvarray := reflect.ValueOf(array).Slice(0, 0)
print(rvarray.Interface()) // @types
print(rvarray.Interface().([]*int)) // @pointsto
print(rvarray.Interface().([]*int)[42]) // @pointsto
// reflect.Value contains a pointer-to-array
rvparray := reflect.ValueOf(&array).Slice(0, 0)
print(rvparray.Interface()) // @types []*int
print(rvparray.Interface().([]*int)) // @pointsto array@array:2
print(rvparray.Interface().([]*int)[42]) // @pointsto main.a
// reflect.Value contains a string.
rvstring := reflect.ValueOf("hi").Slice(0, 0)
print(rvstring.Interface()) // @types string
// reflect.Value contains a (named) string type.
rvS := reflect.ValueOf(S("hi")).Slice(0, 0)
print(rvS.Interface()) // @types S
// reflect.Value contains a non-array pointer.
rvptr := reflect.ValueOf(new(int)).Slice(0, 0)
print(rvptr.Interface()) // @types
// reflect.Value contains a non-string basic type.
rvint := reflect.ValueOf(3).Slice(0, 0)
print(rvint.Interface()) // @types
}
func reflectValueBytes() {
sl1 := make([]byte, 0) // @line ar5sl1
sl2 := make([]byte, 0) // @line ar5sl2
rvsl1 := reflect.ValueOf(sl1)
print(rvsl1.Interface()) // @types []byte
print(rvsl1.Interface().([]byte)) // @pointsto makeslice@ar5sl1:13
print(rvsl1.Bytes()) // @pointsto makeslice@ar5sl1:13
rvsl2 := reflect.ValueOf(123)
rvsl2.SetBytes(sl2)
print(rvsl2.Interface()) // @types int
print(rvsl2.Interface().([]byte)) // @pointsto
print(rvsl2.Bytes()) // @pointsto
rvsl3 := reflect.ValueOf([]byte(nil))
rvsl3.SetBytes(sl2)
print(rvsl3.Interface()) // @types []byte
print(rvsl3.Interface().([]byte)) // @pointsto makeslice@ar5sl2:13
print(rvsl3.Bytes()) // @pointsto makeslice@ar5sl2:13
}
func reflectValueIndex() {
slice := []*int{&a} // @line ar6slice
rv1 := reflect.ValueOf(slice)
print(rv1.Index(42).Interface()) // @types *int
print(rv1.Index(42).Interface().(*int)) // @pointsto main.a
array := [10]*int{&a}
rv2 := reflect.ValueOf(array)
print(rv2.Index(42).Interface()) // @types *int
print(rv2.Index(42).Interface().(*int)) // @pointsto main.a
rv3 := reflect.ValueOf("string")
print(rv3.Index(42).Interface()) // @types rune
rv4 := reflect.ValueOf(&array)
print(rv4.Index(42).Interface()) // @types
rv5 := reflect.ValueOf(3)
print(rv5.Index(42).Interface()) // @types
}
func reflectValueElem() {
// Interface.
var iface interface{} = &a
rv1 := reflect.ValueOf(&iface).Elem()
print(rv1.Interface()) // @types *int
print(rv1.Interface().(*int)) // @pointsto main.a
print(rv1.Elem().Interface()) // @types *int
print(rv1.Elem().Interface().(*int)) // @pointsto main.a
print(reflect.ValueOf(new(interface{})).Elem().Elem()) // @types
// Pointer.
ptr := &a
rv2 := reflect.ValueOf(&ptr)
print(rv2.Elem().Interface()) // @types *int
print(rv2.Elem().Interface().(*int)) // @pointsto main.a
// No other type works with (rV).Elem, not even those that
// work with (rT).Elem: slice, array, map, chan.
rv3 := reflect.ValueOf([]*int{&a})
print(rv3.Elem().Interface()) // @types
rv4 := reflect.ValueOf([10]*int{&a})
print(rv4.Elem().Interface()) // @types
rv5 := reflect.ValueOf(map[*int]*int{&a: &b})
print(rv5.Elem().Interface()) // @types
ch := make(chan *int)
ch <- &a
rv6 := reflect.ValueOf(ch)
print(rv6.Elem().Interface()) // @types
rv7 := reflect.ValueOf(3)
print(rv7.Elem().Interface()) // @types
}
func reflectTypeElem() {
rt1 := reflect.TypeOf(make([]*int, 0))
print(reflect.Zero(rt1.Elem())) // @types *int
rt2 := reflect.TypeOf([10]*int{})
print(reflect.Zero(rt2.Elem())) // @types *int
rt3 := reflect.TypeOf(map[*int]*int{})
print(reflect.Zero(rt3.Elem())) // @types *int
rt4 := reflect.TypeOf(make(chan *int))
print(reflect.Zero(rt4.Elem())) // @types *int
ptr := &a
rt5 := reflect.TypeOf(&ptr)
print(reflect.Zero(rt5.Elem())) // @types *int
rt6 := reflect.TypeOf(3)
print(reflect.Zero(rt6.Elem())) // @types
}
func reflectPtrTo() {
tInt := reflect.TypeOf(3)
tPtrInt := reflect.PtrTo(tInt)
print(reflect.Zero(tPtrInt)) // @types *int
tPtrPtrInt := reflect.PtrTo(tPtrInt)
print(reflect.Zero(tPtrPtrInt)) // @types **int
}
func reflectSliceOf() {
tInt := reflect.TypeOf(3)
tSliceInt := reflect.SliceOf(tInt)
print(reflect.Zero(tSliceInt)) // @types []int
}
type T struct{ x int }
func reflectMakeSlice() {
rt := []reflect.Type{
reflect.TypeOf(3),
reflect.TypeOf([]int{}),
reflect.TypeOf([]T{}),
}[0]
sl := reflect.MakeSlice(rt, 0, 0)
print(sl) // @types []int | []T
print(sl) // @pointsto <alloc in reflect.MakeSlice> | <alloc in reflect.MakeSlice>
print(&sl.Interface().([]T)[0].x) // @pointsto <alloc in reflect.MakeSlice>[*].x
}
func main() {
reflectValueSlice()
reflectValueBytes()
reflectValueIndex()
reflectValueElem()
reflectTypeElem()
reflectPtrTo()
reflectSliceOf()
reflectMakeSlice()
}
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