1 // Copyright 2016 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 // This file contains tests for sizes. 6 7 package types_test 8 9 import ( 10 "go/ast" 11 "go/importer" 12 "go/parser" 13 "go/token" 14 "go/types" 15 "testing" 16 ) 17 18 // findStructType typechecks src and returns the first struct type encountered. 19 func findStructType(t *testing.T, src string) *types.Struct { 20 fset := token.NewFileSet() 21 f, err := parser.ParseFile(fset, "x.go", src, 0) 22 if err != nil { 23 t.Fatal(err) 24 } 25 info := types.Info{Types: make(map[ast.Expr]types.TypeAndValue)} 26 var conf types.Config 27 _, err = conf.Check("x", fset, []*ast.File{f}, &info) 28 if err != nil { 29 t.Fatal(err) 30 } 31 for _, tv := range info.Types { 32 if ts, ok := tv.Type.(*types.Struct); ok { 33 return ts 34 } 35 } 36 t.Fatalf("failed to find a struct type in src:\n%s\n", src) 37 return nil 38 } 39 40 // Issue 16316 41 func TestMultipleSizeUse(t *testing.T) { 42 const src = ` 43 package main 44 45 type S struct { 46 i int 47 b bool 48 s string 49 n int 50 } 51 ` 52 ts := findStructType(t, src) 53 sizes := types.StdSizes{WordSize: 4, MaxAlign: 4} 54 if got := sizes.Sizeof(ts); got != 20 { 55 t.Errorf("Sizeof(%v) with WordSize 4 = %d want 20", ts, got) 56 } 57 sizes = types.StdSizes{WordSize: 8, MaxAlign: 8} 58 if got := sizes.Sizeof(ts); got != 40 { 59 t.Errorf("Sizeof(%v) with WordSize 8 = %d want 40", ts, got) 60 } 61 } 62 63 // Issue 16464 64 func TestAlignofNaclSlice(t *testing.T) { 65 const src = ` 66 package main 67 68 var s struct { 69 x *int 70 y []byte 71 } 72 ` 73 ts := findStructType(t, src) 74 sizes := &types.StdSizes{WordSize: 4, MaxAlign: 8} 75 var fields []*types.Var 76 // Make a copy manually :( 77 for i := 0; i < ts.NumFields(); i++ { 78 fields = append(fields, ts.Field(i)) 79 } 80 offsets := sizes.Offsetsof(fields) 81 if offsets[0] != 0 || offsets[1] != 4 { 82 t.Errorf("OffsetsOf(%v) = %v want %v", ts, offsets, []int{0, 4}) 83 } 84 } 85 86 func TestIssue16902(t *testing.T) { 87 const src = ` 88 package a 89 90 import "unsafe" 91 92 const _ = unsafe.Offsetof(struct{ x int64 }{}.x) 93 ` 94 fset := token.NewFileSet() 95 f, err := parser.ParseFile(fset, "x.go", src, 0) 96 if err != nil { 97 t.Fatal(err) 98 } 99 info := types.Info{Types: make(map[ast.Expr]types.TypeAndValue)} 100 conf := types.Config{ 101 Importer: importer.Default(), 102 Sizes: &types.StdSizes{WordSize: 8, MaxAlign: 8}, 103 } 104 _, err = conf.Check("x", fset, []*ast.File{f}, &info) 105 if err != nil { 106 t.Fatal(err) 107 } 108 for _, tv := range info.Types { 109 _ = conf.Sizes.Sizeof(tv.Type) 110 _ = conf.Sizes.Alignof(tv.Type) 111 } 112 } 113
