libgo/go/html/template/clone_test.go

   1 // Copyright 2011 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 template
   6
   7 import (
   8         "bytes"
   9         "errors"
  10         "fmt"
  11         "io/ioutil"
  12         "sync"
  13         "testing"
  14         "text/template/parse"
  15 )
  16
  17 func TestAddParseTree(t *testing.T) {
  18         root := Must(New("root").Parse(`{{define "a"}} {{.}} {{template "b"}} {{.}} "></a>{{end}}`))
  19         tree, err := parse.Parse("t", `{{define "b"}}<a href="{{end}}`, "", "", nil, nil)
  20         if err != nil {
  21                 t.Fatal(err)
  22         }
  23         added := Must(root.AddParseTree("b", tree["b"]))
  24         b := new(bytes.Buffer)
  25         err = added.ExecuteTemplate(b, "a", "1>0")
  26         if err != nil {
  27                 t.Fatal(err)
  28         }
  29         if got, want := b.String(), ` 1&gt;0 <a href=" 1%3e0 "></a>`; got != want {
  30                 t.Errorf("got %q want %q", got, want)
  31         }
  32 }
  33
  34 func TestClone(t *testing.T) {
  35         // The {{.}} will be executed with data "<i>*/" in different contexts.
  36         // In the t0 template, it will be in a text context.
  37         // In the t1 template, it will be in a URL context.
  38         // In the t2 template, it will be in a JavaScript context.
  39         // In the t3 template, it will be in a CSS context.
  40         const tmpl = `{{define "a"}}{{template "lhs"}}{{.}}{{template "rhs"}}{{end}}`
  41         b := new(bytes.Buffer)
  42
  43         // Create an incomplete template t0.
  44         t0 := Must(New("t0").Parse(tmpl))
  45
  46         // Clone t0 as t1.
  47         t1 := Must(t0.Clone())
  48         Must(t1.Parse(`{{define "lhs"}} <a href=" {{end}}`))
  49         Must(t1.Parse(`{{define "rhs"}} "></a> {{end}}`))
  50
  51         // Execute t1.
  52         b.Reset()
  53         if err := t1.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
  54                 t.Fatal(err)
  55         }
  56         if got, want := b.String(), ` <a href=" %3ci%3e*/ "></a> `; got != want {
  57                 t.Errorf("t1: got %q want %q", got, want)
  58         }
  59
  60         // Clone t0 as t2.
  61         t2 := Must(t0.Clone())
  62         Must(t2.Parse(`{{define "lhs"}} <p onclick="javascript: {{end}}`))
  63         Must(t2.Parse(`{{define "rhs"}} "></p> {{end}}`))
  64
  65         // Execute t2.
  66         b.Reset()
  67         if err := t2.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
  68                 t.Fatal(err)
  69         }
  70         if got, want := b.String(), ` <p onclick="javascript: &#34;\u003ci\u003e*/&#34; "></p> `; got != want {
  71                 t.Errorf("t2: got %q want %q", got, want)
  72         }
  73
  74         // Clone t0 as t3, but do not execute t3 yet.
  75         t3 := Must(t0.Clone())
  76         Must(t3.Parse(`{{define "lhs"}} <style> {{end}}`))
  77         Must(t3.Parse(`{{define "rhs"}} </style> {{end}}`))
  78
  79         // Complete t0.
  80         Must(t0.Parse(`{{define "lhs"}} ( {{end}}`))
  81         Must(t0.Parse(`{{define "rhs"}} ) {{end}}`))
  82
  83         // Clone t0 as t4. Redefining the "lhs" template should not fail.
  84         t4 := Must(t0.Clone())
  85         if _, err := t4.Parse(`{{define "lhs"}} OK {{end}}`); err != nil {
  86                 t.Errorf(`redefine "lhs": got err %v want nil`, err)
  87         }
  88         // Cloning t1 should fail as it has been executed.
  89         if _, err := t1.Clone(); err == nil {
  90                 t.Error("cloning t1: got nil err want non-nil")
  91         }
  92         // Redefining the "lhs" template in t1 should fail as it has been executed.
  93         if _, err := t1.Parse(`{{define "lhs"}} OK {{end}}`); err == nil {
  94                 t.Error(`redefine "lhs": got nil err want non-nil`)
  95         }
  96
  97         // Execute t0.
  98         b.Reset()
  99         if err := t0.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
 100                 t.Fatal(err)
 101         }
 102         if got, want := b.String(), ` ( &lt;i&gt;*/ ) `; got != want {
 103                 t.Errorf("t0: got %q want %q", got, want)
 104         }
 105
 106         // Clone t0. This should fail, as t0 has already executed.
 107         if _, err := t0.Clone(); err == nil {
 108                 t.Error(`t0.Clone(): got nil err want non-nil`)
 109         }
 110
 111         // Similarly, cloning sub-templates should fail.
 112         if _, err := t0.Lookup("a").Clone(); err == nil {
 113                 t.Error(`t0.Lookup("a").Clone(): got nil err want non-nil`)
 114         }
 115         if _, err := t0.Lookup("lhs").Clone(); err == nil {
 116                 t.Error(`t0.Lookup("lhs").Clone(): got nil err want non-nil`)
 117         }
 118
 119         // Execute t3.
 120         b.Reset()
 121         if err := t3.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
 122                 t.Fatal(err)
 123         }
 124         if got, want := b.String(), ` <style> ZgotmplZ </style> `; got != want {
 125                 t.Errorf("t3: got %q want %q", got, want)
 126         }
 127 }
 128
 129 func TestTemplates(t *testing.T) {
 130         names := []string{"t0", "a", "lhs", "rhs"}
 131         // Some template definitions borrowed from TestClone.
 132         const tmpl = `
 133                 {{define "a"}}{{template "lhs"}}{{.}}{{template "rhs"}}{{end}}
 134                 {{define "lhs"}} <a href=" {{end}}
 135                 {{define "rhs"}} "></a> {{end}}`
 136         t0 := Must(New("t0").Parse(tmpl))
 137         templates := t0.Templates()
 138         if len(templates) != len(names) {
 139                 t.Errorf("expected %d templates; got %d", len(names), len(templates))
 140         }
 141         for _, name := range names {
 142                 found := false
 143                 for _, tmpl := range templates {
 144                         if name == tmpl.text.Name() {
 145                                 found = true
 146                                 break
 147                         }
 148                 }
 149                 if !found {
 150                         t.Error("could not find template", name)
 151                 }
 152         }
 153 }
 154
 155 // This used to crash; https://golang.org/issue/3281
 156 func TestCloneCrash(t *testing.T) {
 157         t1 := New("all")
 158         Must(t1.New("t1").Parse(`{{define "foo"}}foo{{end}}`))
 159         t1.Clone()
 160 }
 161
 162 // Ensure that this guarantee from the docs is upheld:
 163 // "Further calls to Parse in the copy will add templates
 164 // to the copy but not to the original."
 165 func TestCloneThenParse(t *testing.T) {
 166         t0 := Must(New("t0").Parse(`{{define "a"}}{{template "embedded"}}{{end}}`))
 167         t1 := Must(t0.Clone())
 168         Must(t1.Parse(`{{define "embedded"}}t1{{end}}`))
 169         if len(t0.Templates())+1 != len(t1.Templates()) {
 170                 t.Error("adding a template to a clone added it to the original")
 171         }
 172         // double check that the embedded template isn't available in the original
 173         err := t0.ExecuteTemplate(ioutil.Discard, "a", nil)
 174         if err == nil {
 175                 t.Error("expected 'no such template' error")
 176         }
 177 }
 178
 179 // https://golang.org/issue/5980
 180 func TestFuncMapWorksAfterClone(t *testing.T) {
 181         funcs := FuncMap{"customFunc": func() (string, error) {
 182                 return "", errors.New("issue5980")
 183         }}
 184
 185         // get the expected error output (no clone)
 186         uncloned := Must(New("").Funcs(funcs).Parse("{{customFunc}}"))
 187         wantErr := uncloned.Execute(ioutil.Discard, nil)
 188
 189         // toClone must be the same as uncloned. It has to be recreated from scratch,
 190         // since cloning cannot occur after execution.
 191         toClone := Must(New("").Funcs(funcs).Parse("{{customFunc}}"))
 192         cloned := Must(toClone.Clone())
 193         gotErr := cloned.Execute(ioutil.Discard, nil)
 194
 195         if wantErr.Error() != gotErr.Error() {
 196                 t.Errorf("clone error message mismatch want %q got %q", wantErr, gotErr)
 197         }
 198 }
 199
 200 // https://golang.org/issue/16101
 201 func TestTemplateCloneExecuteRace(t *testing.T) {
 202         const (
 203                 input   = `<title>{{block "a" .}}a{{end}}</title><body>{{block "b" .}}b{{end}}<body>`
 204                 overlay = `{{define "b"}}A{{end}}`
 205         )
 206         outer := Must(New("outer").Parse(input))
 207         tmpl := Must(Must(outer.Clone()).Parse(overlay))
 208
 209         var wg sync.WaitGroup
 210         for i := 0; i < 10; i++ {
 211                 wg.Add(1)
 212                 go func() {
 213                         defer wg.Done()
 214                         for i := 0; i < 100; i++ {
 215                                 if err := tmpl.Execute(ioutil.Discard, "data"); err != nil {
 216                                         panic(err)
 217                                 }
 218                         }
 219                 }()
 220         }
 221         wg.Wait()
 222 }
 223
 224 func TestTemplateCloneLookup(t *testing.T) {
 225         // Template.escape makes an assumption that the template associated
 226         // with t.Name() is t. Check that this holds.
 227         tmpl := Must(New("x").Parse("a"))
 228         tmpl = Must(tmpl.Clone())
 229         if tmpl.Lookup(tmpl.Name()) != tmpl {
 230                 t.Error("after Clone, tmpl.Lookup(tmpl.Name()) != tmpl")
 231         }
 232 }
 233
 234 func TestCloneGrowth(t *testing.T) {
 235         tmpl := Must(New("root").Parse(`<title>{{block "B". }}Arg{{end}}</title>`))
 236         tmpl = Must(tmpl.Clone())
 237         Must(tmpl.Parse(`{{define "B"}}Text{{end}}`))
 238         for i := 0; i < 10; i++ {
 239                 tmpl.Execute(ioutil.Discard, nil)
 240         }
 241         if len(tmpl.DefinedTemplates()) > 200 {
 242                 t.Fatalf("too many templates: %v", len(tmpl.DefinedTemplates()))
 243         }
 244 }
 245
 246 // https://golang.org/issue/17735
 247 func TestCloneRedefinedName(t *testing.T) {
 248         const base = `
 249 {{ define "a" -}}<title>{{ template "b" . -}}</title>{{ end -}}
 250 {{ define "b" }}{{ end -}}
 251 `
 252         const page = `{{ template "a" . }}`
 253
 254         t1 := Must(New("a").Parse(base))
 255
 256         for i := 0; i < 2; i++ {
 257                 t2 := Must(t1.Clone())
 258                 t2 = Must(t2.New(fmt.Sprintf("%d", i)).Parse(page))
 259                 err := t2.Execute(ioutil.Discard, nil)
 260                 if err != nil {
 261                         t.Fatal(err)
 262                 }
 263         }
 264 }