mirror of
https://github.com/golang/go
synced 2024-09-04 23:44:16 +00:00
[dev.typeparams] cmd/compile/internal/types2: cleanups around receiver type checks
Generic receiver types may be defined such that an instantiated receiver ends up being a pointer type. Disallow them as we do for non-generic receivers. Change-Id: I6612a52615a2999375c35aa1d69ab42f37d9f55d Reviewed-on: https://go-review.googlesource.com/c/go/+/333770 Trust: Robert Griesemer <gri@golang.org> Run-TryBot: Robert Griesemer <gri@golang.org> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
This commit is contained in:
parent
95f8e64fc0
commit
2a8087817c
|
@ -211,9 +211,10 @@ func (check *Checker) funcType(sig *Signature, recvPar *syntax.Field, tparams []
|
|||
|
||||
// spec: "The receiver type must be of the form T or *T where T is a type name."
|
||||
// (ignore invalid types - error was reported before)
|
||||
if t := rtyp; t != Typ[Invalid] {
|
||||
if rtyp != Typ[Invalid] {
|
||||
var err string
|
||||
if T := asNamed(t); T != nil {
|
||||
switch T := rtyp.(type) {
|
||||
case *Named:
|
||||
// spec: "The type denoted by T is called the receiver base type; it must not
|
||||
// be a pointer or interface type and it must be declared in the same package
|
||||
// as the method."
|
||||
|
@ -224,23 +225,30 @@ func (check *Checker) funcType(sig *Signature, recvPar *syntax.Field, tparams []
|
|||
err = ""
|
||||
}
|
||||
} else {
|
||||
switch u := optype(T).(type) {
|
||||
// The underlying type of a receiver base type can be a type parameter;
|
||||
// e.g. for methods with a generic receiver T[P] with type T[P any] P.
|
||||
underIs(T, func(u Type) bool {
|
||||
switch u := u.(type) {
|
||||
case *Basic:
|
||||
// unsafe.Pointer is treated like a regular pointer
|
||||
if u.kind == UnsafePointer {
|
||||
err = "unsafe.Pointer"
|
||||
return false
|
||||
}
|
||||
case *Pointer, *Interface:
|
||||
err = "pointer or interface type"
|
||||
return false
|
||||
}
|
||||
return true
|
||||
})
|
||||
}
|
||||
} else if T := asBasic(t); T != nil {
|
||||
case *Basic:
|
||||
err = "basic or unnamed type"
|
||||
if check.conf.CompilerErrorMessages {
|
||||
check.errorf(recv.pos, "cannot define new methods on non-local type %s", recv.typ)
|
||||
err = ""
|
||||
}
|
||||
} else {
|
||||
default:
|
||||
check.errorf(recv.pos, "invalid receiver type %s", recv.typ)
|
||||
}
|
||||
if err != "" {
|
||||
|
|
|
@ -6,6 +6,8 @@
|
|||
|
||||
package p
|
||||
|
||||
import "unsafe"
|
||||
|
||||
// Parameterized types may have methods.
|
||||
type T1[A any] struct{ a A }
|
||||
|
||||
|
@ -94,3 +96,18 @@ func (_ T2[_, _, _]) _() int { return 42 }
|
|||
type T0 struct{}
|
||||
func (T0) _() {}
|
||||
func (T1[A]) _() {}
|
||||
|
||||
// A generic receiver type may constrain its type parameter such
|
||||
// that it must be a pointer type. Such receiver types are not
|
||||
// permitted.
|
||||
type T3a[P interface{ ~int | ~string | ~float64 }] P
|
||||
|
||||
func (T3a[_]) m() {} // this is ok
|
||||
|
||||
type T3b[P interface{ ~unsafe.Pointer }] P
|
||||
|
||||
func (T3b /* ERROR invalid receiver */ [_]) m() {}
|
||||
|
||||
type T3c[P interface{ *int | *string }] P
|
||||
|
||||
func (T3c /* ERROR invalid receiver */ [_]) m() {}
|
||||
|
|
Loading…
Reference in a new issue