[dev.typeparams] cmd/compile/internal/types2: implement close(ch) where ch is of...

Change-Id: I45189468553e83390fd2640b5708c60a7852fbb5
Reviewed-on: https://go-review.googlesource.com/c/go/+/333713
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>

diff --git a/src/cmd/compile/internal/types2/builtins.go b/src/cmd/compile/internal/types2/builtins.go
index 83d1743ee2fca5718bc645639f84a884169298f8..e1795aedace14ec1ccf562d4cb1782b7212e7933 100644 (file)
--- a/src/cmd/compile/internal/types2/builtins.go
+++ b/src/cmd/compile/internal/types2/builtins.go
@@ -212,19 +212,23 @@ func (check *Checker) builtin(x *operand, call *syntax.CallExpr, id builtinId) (
 
        case _Close:
                // close(c)
-               c := asChan(x.typ)
-               if c == nil {
-                       check.errorf(x, invalidArg+"%s is not a channel", x)
-                       return
-               }
-               if c.dir == RecvOnly {
-                       check.errorf(x, invalidArg+"%s must not be a receive-only channel", x)
+               if !underIs(x.typ, func(u Type) bool {
+                       uch, _ := u.(*Chan)
+                       if uch == nil {
+                               check.errorf(x, invalidOp+"cannot close non-channel %s", x)
+                               return false
+                       }
+                       if uch.dir == RecvOnly {
+                               check.errorf(x, invalidOp+"cannot close receive-only channel %s", x)
+                               return false
+                       }
+                       return true
+               }) {
                        return
                }
-
                x.mode = novalue
                if check.Types != nil {
-                       check.recordBuiltinType(call.Fun, makeSig(nil, c))
+                       check.recordBuiltinType(call.Fun, makeSig(nil, x.typ))
                }
 
        case _Complex:

diff --git a/src/cmd/compile/internal/types2/testdata/check/builtins.go2 b/src/cmd/compile/internal/types2/testdata/check/builtins.go2
index 5bb67efec9d429d201d95b27fc5136b82f560f56..71295bf4342f78cdfcc0bd2420fce85e250b992a 100644 (file)
--- a/src/cmd/compile/internal/types2/testdata/check/builtins.go2
+++ b/src/cmd/compile/internal/types2/testdata/check/builtins.go2
@@ -6,6 +6,45 @@
 
 package builtins
 
+// close
+
+type C0 interface{ int }
+type C1 interface{ chan int }
+type C2 interface{ chan int | <-chan int }
+type C3 interface{ chan int | chan float32 }
+type C4 interface{ chan int | chan<- int }
+type C5[T any] interface{ ~chan T | chan<- T }
+
+func _[T any](ch T) {
+       close(ch /* ERROR cannot close non-channel */)
+}
+
+func _[T C0](ch T) {
+       close(ch /* ERROR cannot close non-channel */)
+}
+
+func _[T C1](ch T) {
+       close(ch)
+}
+
+func _[T C2](ch T) {
+       close(ch /* ERROR cannot close receive-only channel */)
+}
+
+func _[T C3](ch T) {
+       close(ch)
+}
+
+func _[T C4](ch T) {
+       close(ch)
+}
+
+func _[T C5[X], X any](ch T) {
+       close(ch)
+}
+
+// make
+
 type Bmc interface {
        ~map[rune]string | ~chan int
 }
@@ -22,31 +61,31 @@ type Bss interface {
        ~[]int | ~[]string
 }
 
-func _[T any] () {
-       _ = make(T /* ERROR invalid argument */ )
-       _ = make(T /* ERROR invalid argument */ , 10)
-       _ = make(T /* ERROR invalid argument */ , 10, 20)
+func _[T any]() {
+       _ = make(T /* ERROR invalid argument */)
+       _ = make(T /* ERROR invalid argument */, 10)
+       _ = make(T /* ERROR invalid argument */, 10, 20)
 }
 
-func _[T Bmc] () {
+func _[T Bmc]() {
        _ = make(T)
        _ = make(T, 10)
        _ = make /* ERROR expects 1 or 2 arguments */ (T, 10, 20)
 }
 
-func _[T Bms] () {
+func _[T Bms]() {
        _ = make /* ERROR expects 2 arguments */ (T)
        _ = make(T, 10)
        _ = make /* ERROR expects 2 arguments */ (T, 10, 20)
 }
 
-func _[T Bcs] () {
+func _[T Bcs]() {
        _ = make /* ERROR expects 2 arguments */ (T)
        _ = make(T, 10)
        _ = make /* ERROR expects 2 arguments */ (T, 10, 20)
 }
 
-func _[T Bss] () {
+func _[T Bss]() {
        _ = make /* ERROR expects 2 or 3 arguments */ (T)
        _ = make(T, 10)
        _ = make(T, 10, 20)

diff --git a/src/cmd/compile/internal/types2/testdata/check/builtins.src b/src/cmd/compile/internal/types2/testdata/check/builtins.src
index 6d1f47129b9c16d2935a66c6eb97a740550041ae..17e4068d6546ea22080d5cd3f4bb3049aa119498 100644 (file)
--- a/src/cmd/compile/internal/types2/testdata/check/builtins.src
+++ b/src/cmd/compile/internal/types2/testdata/check/builtins.src
@@ -144,7 +144,7 @@ func close1() {
        var r <-chan int
        close() // ERROR not enough arguments
        close(1, 2) // ERROR too many arguments
-       close(42 /* ERROR not a channel */)
+       close(42 /* ERROR cannot close non-channel */)
        close(r /* ERROR receive-only channel */)
        close(c)
        _ = close /* ERROR used as value */ (c)

diff --git a/src/cmd/compile/internal/types2/type.go b/src/cmd/compile/internal/types2/type.go
index c2da97605b133e1dcef6d5289c9df028ddf30920..84cf36de2c1b84986c07d82b8a4e1d8bd58bb19b 100644 (file)
--- a/src/cmd/compile/internal/types2/type.go
+++ b/src/cmd/compile/internal/types2/type.go
@@ -105,8 +105,6 @@ func asPointer(t Type) *Pointer {
        return op
 }
 
-// asTuple is not needed - not provided
-
 func asSignature(t Type) *Signature {
        op, _ := optype(t).(*Signature)
        return op
@@ -117,11 +115,6 @@ func asMap(t Type) *Map {
        return op
 }
 
-func asChan(t Type) *Chan {
-       op, _ := optype(t).(*Chan)
-       return op
-}
-
 // If the argument to asInterface, asNamed, or asTypeParam is of the respective type
 // (possibly after expanding an instance type), these methods return that type.
 // Otherwise the result is nil.

diff --git a/test/chan/perm.go b/test/chan/perm.go
index 4c94ab7ffaeefb2e96cd260768e2a4ceb2486983..04046723a4f6fefda18911b4bb9351086177ae0f 100644 (file)
--- a/test/chan/perm.go
+++ b/test/chan/perm.go
@@ -66,5 +66,5 @@ func main() {
        close(c)
        close(cs)
        close(cr) // ERROR "receive"
-       close(n)  // ERROR "invalid operation.*non-chan type|must be channel|not a channel"
+       close(n)  // ERROR "invalid operation.*non-chan type|must be channel|non-channel"
 }