}
func writeTypeName(buf *bytes.Buffer, obj *TypeName, qf Qualifier) {
- s := "<Named w/o object>"
- if obj != nil {
- if obj.pkg != nil {
- writePackage(buf, obj.pkg, qf)
+ if obj == nil {
+ buf.WriteString("<Named w/o object>")
+ return
+ }
+ if obj.pkg != nil {
+ writePackage(buf, obj.pkg, qf)
+ }
+ buf.WriteString(obj.name)
+
+ if instanceHashing != 0 {
+ // For local defined types, use the (original!) TypeName's position
+ // to disambiguate. This is overkill, and could probably instead
+ // just be the pointer value (if we assume a non-moving GC) or
+ // a unique ID (like cmd/compile uses). But this works for now,
+ // and is convenient for debugging.
+
+ // TODO(mdempsky): I still don't fully understand why typ.orig.orig
+ // can differ from typ.orig, or whether looping more than twice is
+ // ever necessary.
+ typ := obj.typ.(*Named)
+ for typ.orig != typ {
+ typ = typ.orig
+ }
+ if orig := typ.obj; orig.pkg != nil && orig.parent != orig.pkg.scope {
+ fmt.Fprintf(buf, "@%q", orig.pos)
}
- // TODO(gri): function-local named types should be displayed
- // differently from named types at package level to avoid
- // ambiguity.
- s = obj.name
}
- buf.WriteString(s)
}
func writeTuple(buf *bytes.Buffer, tup *Tuple, variadic bool, qf Qualifier, visited []Type) {
--- /dev/null
+// run -gcflags=all="-d=unified -G"
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This test case stress tests a number of subtle cases involving
+// nested type-parameterized declarations. At a high-level, it
+// declares a generic function that contains a generic type
+// declaration:
+//
+// func F[A intish]() {
+// type T[B intish] struct{}
+//
+// // store reflect.Type tuple (A, B, F[A].T[B]) in tests
+// }
+//
+// It then instantiates this function with a variety of type arguments
+// for A and B. Particularly tricky things like shadowed types.
+//
+// From this data it tests two things:
+//
+// 1. Given tuples (A, B, F[A].T[B]) and (A', B', F[A'].T[B']),
+// F[A].T[B] should be identical to F[A'].T[B'] iff (A, B) is
+// identical to (A', B').
+//
+// 2. A few of the instantiations are constructed to be identical, and
+// it tests that exactly these pairs are duplicated (by golden
+// output comparison to nested.out).
+//
+// In both cases, we're effectively using the compiler's existing
+// runtime.Type handling (which is well tested) of type identity of A
+// and B as a way to help bootstrap testing and validate its new
+// runtime.Type handling of F[A].T[B].
+//
+// This isn't perfect, but it smoked out a handful of issues in
+// gotypes2 and unified IR.
+
+package main
+
+import (
+ "fmt"
+ "reflect"
+)
+
+type test struct {
+ TArgs [2]reflect.Type
+ Instance reflect.Type
+}
+
+var tests []test
+
+type intish interface{ ~int }
+
+type Int int
+type GlobalInt = Int // allow access to global Int, even when shadowed
+
+func F[A intish]() {
+ add := func(B, T interface{}) {
+ tests = append(tests, test{
+ TArgs: [2]reflect.Type{
+ reflect.TypeOf(A(0)),
+ reflect.TypeOf(B),
+ },
+ Instance: reflect.TypeOf(T),
+ })
+ }
+
+ type Int int
+
+ type T[B intish] struct{}
+
+ add(int(0), T[int]{})
+ add(Int(0), T[Int]{})
+ add(GlobalInt(0), T[GlobalInt]{})
+ add(A(0), T[A]{}) // NOTE: intentionally dups with int and GlobalInt
+
+ type U[_ any] int
+ type V U[int]
+ type W V
+
+ add(U[int](0), T[U[int]]{})
+ add(U[Int](0), T[U[Int]]{})
+ add(U[GlobalInt](0), T[U[GlobalInt]]{})
+ add(U[A](0), T[U[A]]{}) // NOTE: intentionally dups with U[int] and U[GlobalInt]
+ add(V(0), T[V]{})
+ add(W(0), T[W]{})
+}
+
+func main() {
+ type Int int
+
+ F[int]()
+ F[Int]()
+ F[GlobalInt]()
+
+ type U[_ any] int
+ type V U[int]
+ type W V
+
+ F[U[int]]()
+ F[U[Int]]()
+ F[U[GlobalInt]]()
+ F[V]()
+ F[W]()
+
+ type X[A any] U[X[A]]
+
+ F[X[int]]()
+ F[X[Int]]()
+ F[X[GlobalInt]]()
+
+ for j, tj := range tests {
+ for i, ti := range tests[:j+1] {
+ if (ti.TArgs == tj.TArgs) != (ti.Instance == tj.Instance) {
+ fmt.Printf("FAIL: %d,%d: %s, but %s\n", i, j, eq(ti.TArgs, tj.TArgs), eq(ti.Instance, tj.Instance))
+ }
+
+ // The test is constructed so we should see a few identical types.
+ // See "NOTE" comments above.
+ if i != j && ti.Instance == tj.Instance {
+ fmt.Printf("%d,%d: %v\n", i, j, ti.Instance)
+ }
+ }
+ }
+}
+
+func eq(a, b interface{}) string {
+ op := "=="
+ if a != b {
+ op = "!="
+ }
+ return fmt.Sprintf("%v %s %v", a, op, b)
+}