[dev.typeparams] go/types: convert testdata/fixedbugs tests to type set sytax

This is a port of CL 324530 to go/types. One error position in
issue39634.go2 was adjusted by a character, to account for go/types'
positioning.

Change-Id: Ie06974ea9ee81d3ae66ef58dba522936ab4ce2d1
Reviewed-on: https://go-review.googlesource.com/c/go/+/326681
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

src/go/types/testdata/fixedbugs/issue39634.go2

@@ -31,12 +31,12 @@ type x7[A any] struct{ foo7 }
 func main7() { var _ foo7 = x7[int]{} }
 
 // crash 8
-type foo8[A any] interface { type A }
+type foo8[A any] interface { ~A }
 func bar8[A foo8[A]](a A) {}
 func main8() {}
 
 // crash 9
-type foo9[A any] interface { type foo9 /* ERROR cannot use interface */ [A] }
+type foo9[A any] interface { ~ /* ERROR cannot use interface */ foo9 [A] }
 func _() { var _ = new(foo9 /* ERROR interface contains type constraints */ [int]) }
 
 // crash 12

src/go/types/testdata/fixedbugs/issue39680.go2

@@ -7,13 +7,13 @@ package p
 import "fmt"
 
 // Minimal test case.
-func _[T interface{type T}](x T) T{
+func _[T interface{~T}](x T) T{
 	return x
 }
 
 // Test case from issue.
 type constr[T any] interface {
-	type T
+	~T
 }
 
 func Print[T constr[T]](s []T) {

src/go/types/testdata/fixedbugs/issue39699.go2

@@ -8,7 +8,7 @@ type T0 interface{
 }
 
 type T1 interface{
-	type int
+	~int
 }
 
 type T2 interface{

src/go/types/testdata/fixedbugs/issue39723.go2

@@ -6,4 +6,4 @@ package p
 
 // A constraint must be an interface; it cannot
 // be a type parameter, for instance.
-func _[A interface{ type int }, B A /* ERROR not an interface */ ]()
+func _[A interface{ ~int }, B A /* ERROR not an interface */ ]()

src/go/types/testdata/fixedbugs/issue39755.go2

@@ -4,14 +4,14 @@
 
 package p
 
-func _[T interface{type map[string]int}](x T) {
+func _[T interface{~map[string]int}](x T) {
 	_ = x == nil
 }
 
 // simplified test case from issue
 
 type PathParamsConstraint interface {
-        type map[string]string, []struct{key, value string}
+        ~map[string]string | ~[]struct{key, value string}
 }
 
 type PathParams[T PathParamsConstraint] struct {

src/go/types/testdata/fixedbugs/issue41124.go2

@@ -7,7 +7,7 @@ package p
 // Test case from issue.
 
 type Nat interface {
-	type Zero, Succ
+	Zero|Succ
 }
 
 type Zero struct{}
@@ -22,7 +22,7 @@ type I1 interface {
 }
 
 type I2 interface {
-	type int
+	~int
 }
 
 type I3 interface {

src/go/types/testdata/fixedbugs/issue42758.go2

@@ -17,7 +17,7 @@ func _[T any](x interface{}){
 }
 
 type constraint interface {
-	type int
+	~int
 }
 
 func _[T constraint](x interface{}){

src/go/types/testdata/fixedbugs/issue45548.go2

@@ -4,7 +4,7 @@
 
 package p
 
-func f[F interface{type *Q}, G interface{type *R}, Q, R any](q Q, r R) {}
+func f[F interface{~*Q}, G interface{~*R}, Q, R any](q Q, r R) {}
 
 func _() {
 	f[*float64, *int](1, 2)

src/go/types/testdata/fixedbugs/issue45635.go2

@@ -13,7 +13,7 @@ type N[T any] struct{}
 var _ N /* ERROR "0 arguments but 1 type parameters" */ []
 
 type I interface {
-	type map[int]int, []int
+	~map[int]int | ~[]int
 }
 
 func _[T I](i, j int) {

src/go/types/testdata/fixedbugs/issue45985.go2

@@ -5,7 +5,7 @@
 package issue45985
 
 // TODO(rFindley): this error should be on app[int] below.
-func app[S /* ERROR "type S = S does not match" */ interface{ type []T }, T any](s S, e T) S {
+func app[S /* ERROR "type S = S does not match" */ interface{ ~[]T }, T any](s S, e T) S {
     return append(s, e)
 }