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

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>

2 files changed, 48 insertions, 9 deletions

diff --git a/src/cmd/compile/internal/types2/testdata/check/builtins.go2 b/src/cmd/compile/internal/types2/testdata/check/builtins.go2
index 5bb67efec9..71295bf434 100644
--- 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 6d1f47129b..17e4068d65 100644
--- 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)