1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
// 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) {
emptySignature := NewSignatureType(nil, nil, nil, nil, nil, false)
tests := []struct {
src string
name1 string
targs1 []Type
name2 string
targs2 []Type
wantEqual bool
}{
{
"package basictype; type T[P any] int",
"T", []Type{Typ[Int]},
"T", []Type{Typ[Int]},
true,
},
{
"package differenttypeargs; type T[P any] int",
"T", []Type{Typ[Int]},
"T", []Type{Typ[String]},
false,
},
{
"package typeslice; type T[P any] int",
"T", []Type{NewSlice(Typ[Int])},
"T", []Type{NewSlice(Typ[Int])},
true,
},
{
// interface{interface{...}} is equivalent to interface{...}
"package equivalentinterfaces; type T[P any] int",
"T", []Type{
NewInterfaceType([]*Func{NewFunc(nopos, nil, "M", emptySignature)}, nil),
},
"T", []Type{
NewInterfaceType(
nil,
[]Type{
NewInterfaceType([]*Func{NewFunc(nopos, nil, "M", emptySignature)}, nil),
},
),
},
true,
},
{
// int|string is equivalent to string|int
"package equivalenttypesets; type T[P any] int",
"T", []Type{
NewInterfaceType(nil, []Type{
NewUnion([]*Term{NewTerm(false, Typ[Int]), NewTerm(false, Typ[String])}),
}),
},
"T", []Type{
NewInterfaceType(nil, []Type{
NewUnion([]*Term{NewTerm(false, Typ[String]), NewTerm(false, Typ[Int])}),
}),
},
true,
},
{
"package basicfunc; func F[P any]() {}",
"F", []Type{Typ[Int]},
"F", []Type{Typ[Int]},
true,
},
{
"package funcslice; func F[P any]() {}",
"F", []Type{NewSlice(Typ[Int])},
"F", []Type{NewSlice(Typ[Int])},
true,
},
{
"package funcwithparams; func F[P any](x string) float64 { return 0 }",
"F", []Type{Typ[Int]},
"F", []Type{Typ[Int]},
true,
},
{
"package differentfuncargs; func F[P any](x string) float64 { return 0 }",
"F", []Type{Typ[Int]},
"F", []Type{Typ[String]},
false,
},
{
"package funcequality; func F1[P any](x int) {}; func F2[Q any](x int) {}",
"F1", []Type{Typ[Int]},
"F2", []Type{Typ[Int]},
false,
},
{
"package funcsymmetry; func F1[P any](x P) {}; func F2[Q any](x Q) {}",
"F1", []Type{Typ[Int]},
"F2", []Type{Typ[Int]},
false,
},
}
for _, test := range tests {
pkg := mustTypecheck(test.src, nil, nil)
t.Run(pkg.Name(), func(t *testing.T) {
ctxt := NewContext()
T1 := pkg.Scope().Lookup(test.name1).Type()
res1, err := Instantiate(ctxt, T1, test.targs1, false)
if err != nil {
t.Fatal(err)
}
T2 := pkg.Scope().Lookup(test.name2).Type()
res2, err := Instantiate(ctxt, T2, test.targs2, false)
if err != nil {
t.Fatal(err)
}
if gotEqual := res1 == res2; gotEqual != test.wantEqual {
t.Errorf("%s == %s: %t, want %t", res1, res2, gotEqual, test.wantEqual)
}
})
}
}
func TestInstantiateNonEquality(t *testing.T) {
const src = "package p; type T[P any] int"
pkg1 := mustTypecheck(src, nil, nil)
pkg2 := mustTypecheck(src, nil, nil)
// 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 = `package 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 := mustTypecheck(src, nil, nil)
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 = `package p
type T[P any] struct{}
func (T[P]) m() {}
var _ T[int]
`
pkg := mustTypecheck(src, nil, nil)
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 buf strings.Builder
for _, r := range s {
// strip #'s and subscript digits
if r < '₀' || '₀'+10 <= r { // '₀' == U+2080
buf.WriteRune(r)
}
}
if buf.Len() < len(s) {
return buf.String()
}
return s
}
|
