| // 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. |
| package types2_test |
| |
| import ( |
| . "cmd/compile/internal/types2" |
| "strings" |
| "testing" |
| ) |
| |
| func TestInstantiateEquality(t *testing.T) { |
| const src = genericPkg + "p; type T[P any] int" |
| pkg, err := pkgFor(".", src, nil) |
| if err != nil { |
| t.Fatal(err) |
| } |
| T := pkg.Scope().Lookup("T").Type().(*Named) |
| // Instantiating the same type twice should result in pointer-equivalent |
| // instances. |
| ctxt := NewContext() |
| res1, err := Instantiate(ctxt, T, []Type{Typ[Int]}, false) |
| if err != nil { |
| t.Fatal(err) |
| } |
| res2, err := Instantiate(ctxt, T, []Type{Typ[Int]}, false) |
| if err != nil { |
| t.Fatal(err) |
| } |
| if res1 != res2 { |
| t.Errorf("first instance (%s) not pointer-equivalent to second instance (%s)", res1, res2) |
| } |
| } |
| func TestInstantiateNonEquality(t *testing.T) { |
| const src = genericPkg + "p; type T[P any] int" |
| pkg1, err := pkgFor(".", src, nil) |
| if err != nil { |
| t.Fatal(err) |
| } |
| pkg2, err := pkgFor(".", src, nil) |
| if err != nil { |
| t.Fatal(err) |
| } |
| // We consider T1 and T2 to be distinct types, so their instances should not |
| // be deduplicated by the context. |
| T1 := pkg1.Scope().Lookup("T").Type().(*Named) |
| T2 := pkg2.Scope().Lookup("T").Type().(*Named) |
| ctxt := NewContext() |
| res1, err := Instantiate(ctxt, T1, []Type{Typ[Int]}, false) |
| if err != nil { |
| t.Fatal(err) |
| } |
| res2, err := Instantiate(ctxt, T2, []Type{Typ[Int]}, false) |
| if err != nil { |
| t.Fatal(err) |
| } |
| if res1 == res2 { |
| t.Errorf("instance from pkg1 (%s) is pointer-equivalent to instance from pkg2 (%s)", res1, res2) |
| } |
| if Identical(res1, res2) { |
| t.Errorf("instance from pkg1 (%s) is identical to instance from pkg2 (%s)", res1, res2) |
| } |
| } |
| |
| func TestMethodInstantiation(t *testing.T) { |
| const prefix = genericPkg + `p |
| |
| type T[P any] struct{} |
| |
| var X T[int] |
| |
| ` |
| tests := []struct { |
| decl string |
| want string |
| }{ |
| {"func (r T[P]) m() P", "func (T[int]).m() int"}, |
| {"func (r T[P]) m(P)", "func (T[int]).m(int)"}, |
| {"func (r *T[P]) m(P)", "func (*T[int]).m(int)"}, |
| {"func (r T[P]) m() T[P]", "func (T[int]).m() T[int]"}, |
| {"func (r T[P]) m(T[P])", "func (T[int]).m(T[int])"}, |
| {"func (r T[P]) m(T[P], P, string)", "func (T[int]).m(T[int], int, string)"}, |
| {"func (r T[P]) m(T[P], T[string], T[int])", "func (T[int]).m(T[int], T[string], T[int])"}, |
| } |
| |
| for _, test := range tests { |
| src := prefix + test.decl |
| pkg, err := pkgFor(".", src, nil) |
| if err != nil { |
| t.Fatal(err) |
| } |
| typ := NewPointer(pkg.Scope().Lookup("X").Type()) |
| obj, _, _ := LookupFieldOrMethod(typ, false, pkg, "m") |
| m, _ := obj.(*Func) |
| if m == nil { |
| t.Fatalf(`LookupFieldOrMethod(%s, "m") = %v, want func m`, typ, obj) |
| } |
| if got := ObjectString(m, RelativeTo(pkg)); got != test.want { |
| t.Errorf("instantiated %q, want %q", got, test.want) |
| } |
| } |
| } |
| |
| func TestImmutableSignatures(t *testing.T) { |
| const src = genericPkg + `p |
| |
| type T[P any] struct{} |
| |
| func (T[P]) m() {} |
| |
| var _ T[int] |
| ` |
| pkg, err := pkgFor(".", src, nil) |
| if err != nil { |
| t.Fatal(err) |
| } |
| typ := pkg.Scope().Lookup("T").Type().(*Named) |
| obj, _, _ := LookupFieldOrMethod(typ, false, pkg, "m") |
| if obj == nil { |
| t.Fatalf(`LookupFieldOrMethod(%s, "m") = %v, want func m`, typ, obj) |
| } |
| |
| // Verify that the original method is not mutated by instantiating T (this |
| // bug manifested when subst did not return a new signature). |
| want := "func (T[P]).m()" |
| if got := stripAnnotations(ObjectString(obj, RelativeTo(pkg))); got != want { |
| t.Errorf("instantiated %q, want %q", got, want) |
| } |
| } |
| |
| // Copied from errors.go. |
| func stripAnnotations(s string) string { |
| var b strings.Builder |
| for _, r := range s { |
| // strip #'s and subscript digits |
| if r < '₀' || '₀'+10 <= r { // '₀' == U+2080 |
| b.WriteRune(r) |
| } |
| } |
| if b.Len() < len(s) { |
| return b.String() |
| } |
| return s |
| } |