| 1 | // Copyright 2018 The Go Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | package typeutil_test |
| 6 | |
| 7 | import ( |
| 8 | "fmt" |
| 9 | "go/ast" |
| 10 | "go/parser" |
| 11 | "go/token" |
| 12 | "go/types" |
| 13 | "strings" |
| 14 | "testing" |
| 15 | |
| 16 | "golang.org/x/tools/go/types/typeutil" |
| 17 | "golang.org/x/tools/internal/typeparams" |
| 18 | ) |
| 19 | |
| 20 | func TestStaticCallee(t *testing.T) { |
| 21 | testStaticCallee(t, []string{ |
| 22 | `package q; |
| 23 | func Abs(x int) int { |
| 24 | if x < 0 { |
| 25 | return -x |
| 26 | } |
| 27 | return x |
| 28 | }`, |
| 29 | `package p |
| 30 | import "q" |
| 31 | |
| 32 | type T int |
| 33 | |
| 34 | func g(int) |
| 35 | |
| 36 | var f = g |
| 37 | |
| 38 | var x int |
| 39 | |
| 40 | type s struct{ f func(int) } |
| 41 | func (s) g(int) |
| 42 | |
| 43 | type I interface{ f(int) } |
| 44 | |
| 45 | var a struct{b struct{c s}} |
| 46 | |
| 47 | var n map[int]func() |
| 48 | var m []func() |
| 49 | |
| 50 | func calls() { |
| 51 | g(x) // a declared func |
| 52 | s{}.g(x) // a concrete method |
| 53 | a.b.c.g(x) // same |
| 54 | _ = q.Abs(x) // declared func, qualified identifier |
| 55 | } |
| 56 | |
| 57 | func noncalls() { |
| 58 | _ = T(x) // a type |
| 59 | f(x) // a var |
| 60 | panic(x) // a built-in |
| 61 | s{}.f(x) // a field |
| 62 | I(nil).f(x) // interface method |
| 63 | m[0]() // a map |
| 64 | n[0]() // a slice |
| 65 | } |
| 66 | `}) |
| 67 | } |
| 68 | |
| 69 | func TestTypeParamStaticCallee(t *testing.T) { |
| 70 | if !typeparams.Enabled { |
| 71 | t.Skip("type parameters are not enabled") |
| 72 | } |
| 73 | testStaticCallee(t, []string{ |
| 74 | `package q |
| 75 | func R[T any]() {} |
| 76 | `, |
| 77 | `package p |
| 78 | import "q" |
| 79 | type I interface{ |
| 80 | i() |
| 81 | } |
| 82 | |
| 83 | type G[T any] func() T |
| 84 | func F[T any]() T { var x T; return x } |
| 85 | |
| 86 | type M[T I] struct{ t T } |
| 87 | func (m M[T]) noncalls() { |
| 88 | m.t.i() // method on a type parameter |
| 89 | } |
| 90 | |
| 91 | func (m M[T]) calls() { |
| 92 | m.calls() // method on a generic type |
| 93 | } |
| 94 | |
| 95 | type Chain[T I] struct{ r struct { s M[T] } } |
| 96 | |
| 97 | type S int |
| 98 | func (S) i() {} |
| 99 | |
| 100 | func Multi[TP0, TP1 any](){} |
| 101 | |
| 102 | func calls() { |
| 103 | _ = F[int]() // instantiated function |
| 104 | _ = (F[int])() // go through parens |
| 105 | M[S]{}.calls() // instantiated method |
| 106 | Chain[S]{}.r.s.calls() // same as above |
| 107 | Multi[int,string]() // multiple type parameters |
| 108 | q.R[int]() // different package |
| 109 | } |
| 110 | |
| 111 | func noncalls() { |
| 112 | _ = G[int](nil)() // instantiated function |
| 113 | } |
| 114 | `}) |
| 115 | } |
| 116 | |
| 117 | // testStaticCallee parses and type checks each file content in contents |
| 118 | // as a single file package in order. Within functions that have the suffix |
| 119 | // "calls" it checks that the CallExprs within have a static callee. |
| 120 | // If the function's name == "calls" all calls must have static callees, |
| 121 | // and if the name != "calls", the calls must not have static callees. |
| 122 | // Failures are reported on t. |
| 123 | func testStaticCallee(t *testing.T, contents []string) { |
| 124 | fset := token.NewFileSet() |
| 125 | packages := make(map[string]*types.Package) |
| 126 | cfg := &types.Config{Importer: closure(packages)} |
| 127 | info := &types.Info{ |
| 128 | Uses: make(map[*ast.Ident]types.Object), |
| 129 | Selections: make(map[*ast.SelectorExpr]*types.Selection), |
| 130 | } |
| 131 | typeparams.InitInstanceInfo(info) |
| 132 | |
| 133 | var files []*ast.File |
| 134 | for i, content := range contents { |
| 135 | // parse |
| 136 | f, err := parser.ParseFile(fset, fmt.Sprintf("%d.go", i), content, 0) |
| 137 | if err != nil { |
| 138 | t.Fatal(err) |
| 139 | } |
| 140 | files = append(files, f) |
| 141 | |
| 142 | // type-check |
| 143 | pkg, err := cfg.Check(f.Name.Name, fset, []*ast.File{f}, info) |
| 144 | if err != nil { |
| 145 | t.Fatal(err) |
| 146 | } |
| 147 | packages[pkg.Path()] = pkg |
| 148 | } |
| 149 | |
| 150 | // check |
| 151 | for _, f := range files { |
| 152 | for _, decl := range f.Decls { |
| 153 | if decl, ok := decl.(*ast.FuncDecl); ok && strings.HasSuffix(decl.Name.Name, "calls") { |
| 154 | wantCallee := decl.Name.Name == "calls" // false within func noncalls() |
| 155 | ast.Inspect(decl.Body, func(n ast.Node) bool { |
| 156 | if call, ok := n.(*ast.CallExpr); ok { |
| 157 | fn := typeutil.StaticCallee(info, call) |
| 158 | if fn == nil && wantCallee { |
| 159 | t.Errorf("%s: StaticCallee returned nil", |
| 160 | fset.Position(call.Lparen)) |
| 161 | } else if fn != nil && !wantCallee { |
| 162 | t.Errorf("%s: StaticCallee returned %s, want nil", |
| 163 | fset.Position(call.Lparen), fn) |
| 164 | } |
| 165 | } |
| 166 | return true |
| 167 | }) |
| 168 | } |
| 169 | } |
| 170 | } |
| 171 | } |
| 172 |
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