1 // Copyright 2012 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 // To avoid a cyclic dependency with go/parser, this file is in a separate package. 6 7 package ast_test 8 9 import ( 10 "bytes" 11 "fmt" 12 . "go/ast" 13 "go/parser" 14 "go/token" 15 "sort" 16 "testing" 17 ) 18 19 const src = ` 20 // the very first comment 21 22 // package p 23 package p /* the name is p */ 24 25 // imports 26 import ( 27 "bytes" // bytes 28 "fmt" // fmt 29 "go/ast" 30 "go/parser" 31 ) 32 33 // T 34 type T struct { 35 a, b, c int // associated with a, b, c 36 // associated with x, y 37 x, y float64 // float values 38 z complex128 // complex value 39 } 40 // also associated with T 41 42 // x 43 var x = 0 // x = 0 44 // also associated with x 45 46 // f1 47 func f1() { 48 /* associated with s1 */ 49 s1() 50 // also associated with s1 51 52 // associated with s2 53 54 // also associated with s2 55 s2() // line comment for s2 56 } 57 // associated with f1 58 // also associated with f1 59 60 // associated with f2 61 62 // f2 63 func f2() { 64 } 65 66 func f3() { 67 i := 1 /* 1 */ + 2 // addition 68 _ = i 69 } 70 71 // the very last comment 72 ` 73 74 // res maps a key of the form "line number: node type" 75 // to the associated comments' text. 76 // 77 var res = map[string]string{ 78 " 5: *ast.File": "the very first comment\npackage p\n", 79 " 5: *ast.Ident": " the name is p\n", 80 " 8: *ast.GenDecl": "imports\n", 81 " 9: *ast.ImportSpec": "bytes\n", 82 "10: *ast.ImportSpec": "fmt\n", 83 "16: *ast.GenDecl": "T\nalso associated with T\n", 84 "17: *ast.Field": "associated with a, b, c\n", 85 "19: *ast.Field": "associated with x, y\nfloat values\n", 86 "20: *ast.Field": "complex value\n", 87 "25: *ast.GenDecl": "x\nx = 0\nalso associated with x\n", 88 "29: *ast.FuncDecl": "f1\nassociated with f1\nalso associated with f1\n", 89 "31: *ast.ExprStmt": " associated with s1\nalso associated with s1\n", 90 "37: *ast.ExprStmt": "associated with s2\nalso associated with s2\nline comment for s2\n", 91 "45: *ast.FuncDecl": "associated with f2\nf2\n", 92 "49: *ast.AssignStmt": "addition\n", 93 "49: *ast.BasicLit": " 1\n", 94 "50: *ast.Ident": "the very last comment\n", 95 } 96 97 func ctext(list []*CommentGroup) string { 98 var buf bytes.Buffer 99 for _, g := range list { 100 buf.WriteString(g.Text()) 101 } 102 return buf.String() 103 } 104 105 func TestCommentMap(t *testing.T) { 106 fset := token.NewFileSet() 107 f, err := parser.ParseFile(fset, "", src, parser.ParseComments) 108 if err != nil { 109 t.Fatal(err) 110 } 111 cmap := NewCommentMap(fset, f, f.Comments) 112 113 // very correct association of comments 114 for n, list := range cmap { 115 key := fmt.Sprintf("%2d: %T", fset.Position(n.Pos()).Line, n) 116 got := ctext(list) 117 want := res[key] 118 if got != want { 119 t.Errorf("%s: got %q; want %q", key, got, want) 120 } 121 } 122 123 // verify that no comments got lost 124 if n := len(cmap.Comments()); n != len(f.Comments) { 125 t.Errorf("got %d comment groups in map; want %d", n, len(f.Comments)) 126 } 127 128 // support code to update test: 129 // set genMap to true to generate res map 130 const genMap = false 131 if genMap { 132 out := make([]string, 0, len(cmap)) 133 for n, list := range cmap { 134 out = append(out, fmt.Sprintf("\t\"%2d: %T\":\t%q,", fset.Position(n.Pos()).Line, n, ctext(list))) 135 } 136 sort.Strings(out) 137 for _, s := range out { 138 fmt.Println(s) 139 } 140 } 141 } 142 143 // TODO(gri): add tests for Filter. 144
