go.dev/cmd/internal/html/template/content_test.go - website - Git at Google

 // Copyright 2011 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 template

 import (
 	"bytes"
 	"fmt"
 	"strings"
 	"testing"
 )

 func TestTypedContent(t *testing.T) {
 	data := []interface{}{
 		`<b> "foo%" O'Reilly &bar;`,
 		CSS(`a[href =~ "//example.com"]#foo`),
 		HTML(`Hello, <b>World</b> &amp;tc!`),
 		HTMLAttr(` dir="ltr"`),
 		JS(`c && alert("Hello, World!");`),
 		JSStr(`Hello, World & O'Reilly\u0021`),
 		URL(`greeting=H%69,&addressee=(World)`),
 		Srcset(`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`),
 		URL(`,foo/,`),
 	}

 	// For each content sensitive escaper, see how it does on
 	// each of the typed strings above.
 	tests := []struct {
 		// A template containing a single {{.}}.
 		input string
 		want  []string
 	}{
 		{
 			`<style>{{.}} { color: blue }</style>`,
 			[]string{
 				`ZgotmplZ`,
 				// Allowed but not escaped.
 				`a[href =~ "//example.com"]#foo`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 			},
 		},
 		{
 			`<div style="{{.}}">`,
 			[]string{
 				`ZgotmplZ`,
 				// Allowed and HTML escaped.
 				`a[href =~ &#34;//example.com&#34;]#foo`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 			},
 		},
 		{
 			`{{.}}`,
 			[]string{
 				`&lt;b&gt; &#34;foo%&#34; O&#39;Reilly &amp;bar;`,
 				`a[href =~ &#34;//example.com&#34;]#foo`,
 				// Not escaped.
 				`Hello, <b>World</b> &amp;tc!`,
 				` dir=&#34;ltr&#34;`,
 				`c &amp;&amp; alert(&#34;Hello, World!&#34;);`,
 				`Hello, World &amp; O&#39;Reilly\u0021`,
 				`greeting=H%69,&amp;addressee=(World)`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`,foo/,`,
 			},
 		},
 		{
 			`<a{{.}}>`,
 			[]string{
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				// Allowed and HTML escaped.
 				` dir="ltr"`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 				`ZgotmplZ`,
 			},
 		},
 		{
 			`<a title={{.}}>`,
 			[]string{
 				`&lt;b&gt;&#32;&#34;foo%&#34;&#32;O&#39;Reilly&#32;&amp;bar;`,
 				`a[href&#32;&#61;~&#32;&#34;//example.com&#34;]#foo`,
 				// Tags stripped, spaces escaped, entity not re-escaped.
 				`Hello,&#32;World&#32;&amp;tc!`,
 				`&#32;dir&#61;&#34;ltr&#34;`,
 				`c&#32;&amp;&amp;&#32;alert(&#34;Hello,&#32;World!&#34;);`,
 				`Hello,&#32;World&#32;&amp;&#32;O&#39;Reilly\u0021`,
 				`greeting&#61;H%69,&amp;addressee&#61;(World)`,
 				`greeting&#61;H%69,&amp;addressee&#61;(World)&#32;2x,&#32;https://golang.org/favicon.ico&#32;500.5w`,
 				`,foo/,`,
 			},
 		},
 		{
 			`<a title='{{.}}'>`,
 			[]string{
 				`&lt;b&gt; &#34;foo%&#34; O&#39;Reilly &amp;bar;`,
 				`a[href =~ &#34;//example.com&#34;]#foo`,
 				// Tags stripped, entity not re-escaped.
 				`Hello, World &amp;tc!`,
 				` dir=&#34;ltr&#34;`,
 				`c &amp;&amp; alert(&#34;Hello, World!&#34;);`,
 				`Hello, World &amp; O&#39;Reilly\u0021`,
 				`greeting=H%69,&amp;addressee=(World)`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`,foo/,`,
 			},
 		},
 		{
 			`<textarea>{{.}}</textarea>`,
 			[]string{
 				`&lt;b&gt; &#34;foo%&#34; O&#39;Reilly &amp;bar;`,
 				`a[href =~ &#34;//example.com&#34;]#foo`,
 				// Angle brackets escaped to prevent injection of close tags, entity not re-escaped.
 				`Hello, &lt;b&gt;World&lt;/b&gt; &amp;tc!`,
 				` dir=&#34;ltr&#34;`,
 				`c &amp;&amp; alert(&#34;Hello, World!&#34;);`,
 				`Hello, World &amp; O&#39;Reilly\u0021`,
 				`greeting=H%69,&amp;addressee=(World)`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`,foo/,`,
 			},
 		},
 		{
 			`<script>alert({{.}})</script>`,
 			[]string{
 				`"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`,
 				`"a[href =~ \"//example.com\"]#foo"`,
 				`"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`,
 				`" dir=\"ltr\""`,
 				// Not escaped.
 				`c && alert("Hello, World!");`,
 				// Escape sequence not over-escaped.
 				`"Hello, World & O'Reilly\u0021"`,
 				`"greeting=H%69,\u0026addressee=(World)"`,
 				`"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`,
 				`",foo/,"`,
 			},
 		},
 		{
 			`<button onclick="alert({{.}})">`,
 			[]string{
 				`&#34;\u003cb\u003e \&#34;foo%\&#34; O&#39;Reilly \u0026bar;&#34;`,
 				`&#34;a[href =~ \&#34;//example.com\&#34;]#foo&#34;`,
 				`&#34;Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!&#34;`,
 				`&#34; dir=\&#34;ltr\&#34;&#34;`,
 				// Not JS escaped but HTML escaped.
 				`c &amp;&amp; alert(&#34;Hello, World!&#34;);`,
 				// Escape sequence not over-escaped.
 				`&#34;Hello, World &amp; O&#39;Reilly\u0021&#34;`,
 				`&#34;greeting=H%69,\u0026addressee=(World)&#34;`,
 				`&#34;greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w&#34;`,
 				`&#34;,foo/,&#34;`,
 			},
 		},
 		{
 			`<script>alert("{{.}}")</script>`,
 			[]string{
 				`\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`,
 				`a[href =~ \u0022\/\/example.com\u0022]#foo`,
 				`Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`,
 				` dir=\u0022ltr\u0022`,
 				`c \u0026\u0026 alert(\u0022Hello, World!\u0022);`,
 				// Escape sequence not over-escaped.
 				`Hello, World \u0026 O\u0027Reilly\u0021`,
 				`greeting=H%69,\u0026addressee=(World)`,
 				`greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`,
 				`,foo\/,`,
 			},
 		},
 		{
 			`<script type="text/javascript">alert("{{.}}")</script>`,
 			[]string{
 				`\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`,
 				`a[href =~ \u0022\/\/example.com\u0022]#foo`,
 				`Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`,
 				` dir=\u0022ltr\u0022`,
 				`c \u0026\u0026 alert(\u0022Hello, World!\u0022);`,
 				// Escape sequence not over-escaped.
 				`Hello, World \u0026 O\u0027Reilly\u0021`,
 				`greeting=H%69,\u0026addressee=(World)`,
 				`greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`,
 				`,foo\/,`,
 			},
 		},
 		{
 			`<script type="text/javascript">alert({{.}})</script>`,
 			[]string{
 				`"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`,
 				`"a[href =~ \"//example.com\"]#foo"`,
 				`"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`,
 				`" dir=\"ltr\""`,
 				// Not escaped.
 				`c && alert("Hello, World!");`,
 				// Escape sequence not over-escaped.
 				`"Hello, World & O'Reilly\u0021"`,
 				`"greeting=H%69,\u0026addressee=(World)"`,
 				`"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`,
 				`",foo/,"`,
 			},
 		},
 		{
 			// Not treated as JS. The output is same as for <div>{{.}}</div>
 			`<script type="golang.org/x/website/go.dev/cmd/internal/text/template">{{.}}</script>`,
 			[]string{
 				`&lt;b&gt; &#34;foo%&#34; O&#39;Reilly &amp;bar;`,
 				`a[href =~ &#34;//example.com&#34;]#foo`,
 				// Not escaped.
 				`Hello, <b>World</b> &amp;tc!`,
 				` dir=&#34;ltr&#34;`,
 				`c &amp;&amp; alert(&#34;Hello, World!&#34;);`,
 				`Hello, World &amp; O&#39;Reilly\u0021`,
 				`greeting=H%69,&amp;addressee=(World)`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`,foo/,`,
 			},
 		},
 		{
 			`<button onclick='alert("{{.}}")'>`,
 			[]string{
 				`\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`,
 				`a[href =~ \u0022\/\/example.com\u0022]#foo`,
 				`Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`,
 				` dir=\u0022ltr\u0022`,
 				`c \u0026\u0026 alert(\u0022Hello, World!\u0022);`,
 				// Escape sequence not over-escaped.
 				`Hello, World \u0026 O\u0027Reilly\u0021`,
 				`greeting=H%69,\u0026addressee=(World)`,
 				`greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`,
 				`,foo\/,`,
 			},
 		},
 		{
 			`<a href="?q={{.}}">`,
 			[]string{
 				`%3cb%3e%20%22foo%25%22%20O%27Reilly%20%26bar%3b`,
 				`a%5bhref%20%3d~%20%22%2f%2fexample.com%22%5d%23foo`,
 				`Hello%2c%20%3cb%3eWorld%3c%2fb%3e%20%26amp%3btc%21`,
 				`%20dir%3d%22ltr%22`,
 				`c%20%26%26%20alert%28%22Hello%2c%20World%21%22%29%3b`,
 				`Hello%2c%20World%20%26%20O%27Reilly%5cu0021`,
 				// Quotes and parens are escaped but %69 is not over-escaped. HTML escaping is done.
 				`greeting=H%69,&amp;addressee=%28World%29`,
 				`greeting%3dH%2569%2c%26addressee%3d%28World%29%202x%2c%20https%3a%2f%2fgolang.org%2ffavicon.ico%20500.5w`,
 				`,foo/,`,
 			},
 		},
 		{
 			`<style>body { background: url('?img={{.}}') }</style>`,
 			[]string{
 				`%3cb%3e%20%22foo%25%22%20O%27Reilly%20%26bar%3b`,
 				`a%5bhref%20%3d~%20%22%2f%2fexample.com%22%5d%23foo`,
 				`Hello%2c%20%3cb%3eWorld%3c%2fb%3e%20%26amp%3btc%21`,
 				`%20dir%3d%22ltr%22`,
 				`c%20%26%26%20alert%28%22Hello%2c%20World%21%22%29%3b`,
 				`Hello%2c%20World%20%26%20O%27Reilly%5cu0021`,
 				// Quotes and parens are escaped but %69 is not over-escaped. HTML escaping is not done.
 				`greeting=H%69,&addressee=%28World%29`,
 				`greeting%3dH%2569%2c%26addressee%3d%28World%29%202x%2c%20https%3a%2f%2fgolang.org%2ffavicon.ico%20500.5w`,
 				`,foo/,`,
 			},
 		},
 		{
 			`<img srcset="{{.}}">`,
 			[]string{
 				`#ZgotmplZ`,
 				`#ZgotmplZ`,
 				// Commas are not esacped
 				`Hello,#ZgotmplZ`,
 				// Leading spaces are not percent escapes.
 				` dir=%22ltr%22`,
 				// Spaces after commas are not percent escaped.
 				`#ZgotmplZ, World!%22%29;`,
 				`Hello,#ZgotmplZ`,
 				`greeting=H%69%2c&amp;addressee=%28World%29`,
 				// Metadata is not escaped.
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`%2cfoo/%2c`,
 			},
 		},
 		{
 			`<img srcset={{.}}>`,
 			[]string{
 				`#ZgotmplZ`,
 				`#ZgotmplZ`,
 				`Hello,#ZgotmplZ`,
 				// Spaces are HTML escaped not %-escaped
 				`&#32;dir&#61;%22ltr%22`,
 				`#ZgotmplZ,&#32;World!%22%29;`,
 				`Hello,#ZgotmplZ`,
 				`greeting&#61;H%69%2c&amp;addressee&#61;%28World%29`,
 				`greeting&#61;H%69,&amp;addressee&#61;(World)&#32;2x,&#32;https://golang.org/favicon.ico&#32;500.5w`,
 				// Commas are escaped.
 				`%2cfoo/%2c`,
 			},
 		},
 		{
 			`<img srcset="{{.}} 2x, https://golang.org/ 500.5w">`,
 			[]string{
 				`#ZgotmplZ`,
 				`#ZgotmplZ`,
 				`Hello,#ZgotmplZ`,
 				` dir=%22ltr%22`,
 				`#ZgotmplZ, World!%22%29;`,
 				`Hello,#ZgotmplZ`,
 				`greeting=H%69%2c&amp;addressee=%28World%29`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`%2cfoo/%2c`,
 			},
 		},
 		{
 			`<img srcset="http://godoc.org/ {{.}}, https://golang.org/ 500.5w">`,
 			[]string{
 				`#ZgotmplZ`,
 				`#ZgotmplZ`,
 				`Hello,#ZgotmplZ`,
 				` dir=%22ltr%22`,
 				`#ZgotmplZ, World!%22%29;`,
 				`Hello,#ZgotmplZ`,
 				`greeting=H%69%2c&amp;addressee=%28World%29`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`%2cfoo/%2c`,
 			},
 		},
 		{
 			`<img srcset="http://godoc.org/?q={{.}} 2x, https://golang.org/ 500.5w">`,
 			[]string{
 				`#ZgotmplZ`,
 				`#ZgotmplZ`,
 				`Hello,#ZgotmplZ`,
 				` dir=%22ltr%22`,
 				`#ZgotmplZ, World!%22%29;`,
 				`Hello,#ZgotmplZ`,
 				`greeting=H%69%2c&amp;addressee=%28World%29`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`%2cfoo/%2c`,
 			},
 		},
 		{
 			`<img srcset="http://godoc.org/ 2x, {{.}} 500.5w">`,
 			[]string{
 				`#ZgotmplZ`,
 				`#ZgotmplZ`,
 				`Hello,#ZgotmplZ`,
 				` dir=%22ltr%22`,
 				`#ZgotmplZ, World!%22%29;`,
 				`Hello,#ZgotmplZ`,
 				`greeting=H%69%2c&amp;addressee=%28World%29`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`%2cfoo/%2c`,
 			},
 		},
 		{
 			`<img srcset="http://godoc.org/ 2x, https://golang.org/ {{.}}">`,
 			[]string{
 				`#ZgotmplZ`,
 				`#ZgotmplZ`,
 				`Hello,#ZgotmplZ`,
 				` dir=%22ltr%22`,
 				`#ZgotmplZ, World!%22%29;`,
 				`Hello,#ZgotmplZ`,
 				`greeting=H%69%2c&amp;addressee=%28World%29`,
 				`greeting=H%69,&amp;addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
 				`%2cfoo/%2c`,
 			},
 		},
 	}

 	for _, test := range tests {
 		tmpl := Must(New("x").Parse(test.input))
 		pre := strings.Index(test.input, "{{.}}")
 		post := len(test.input) - (pre + 5)
 		var b bytes.Buffer
 		for i, x := range data {
 			b.Reset()
 			if err := tmpl.Execute(&b, x); err != nil {
 				t.Errorf("%q with %v: %s", test.input, x, err)
 				continue
 			}
 			if want, got := test.want[i], b.String()[pre:b.Len()-post]; want != got {
 				t.Errorf("%q with %v:\nwant\n\t%q,\ngot\n\t%q\n", test.input, x, want, got)
 				continue
 			}
 		}
 	}
 }

 // Test that we print using the String method. Was issue 3073.
 type myStringer struct {
 	v int
 }

 func (s *myStringer) String() string {
 	return fmt.Sprintf("string=%d", s.v)
 }

 type errorer struct {
 	v int
 }

 func (s *errorer) Error() string {
 	return fmt.Sprintf("error=%d", s.v)
 }

 func TestStringer(t *testing.T) {
 	s := &myStringer{3}
 	b := new(bytes.Buffer)
 	tmpl := Must(New("x").Parse("{{.}}"))
 	if err := tmpl.Execute(b, s); err != nil {
 		t.Fatal(err)
 	}
 	var expect = "string=3"
 	if b.String() != expect {
 		t.Errorf("expected %q got %q", expect, b.String())
 	}
 	e := &errorer{7}
 	b.Reset()
 	if err := tmpl.Execute(b, e); err != nil {
 		t.Fatal(err)
 	}
 	expect = "error=7"
 	if b.String() != expect {
 		t.Errorf("expected %q got %q", expect, b.String())
 	}
 }

 // https://golang.org/issue/5982
 func TestEscapingNilNonemptyInterfaces(t *testing.T) {
 	tmpl := Must(New("x").Parse("{{.E}}"))

 	got := new(bytes.Buffer)
 	testData := struct{ E error }{} // any non-empty interface here will do; error is just ready at hand
 	tmpl.Execute(got, testData)

 	// A non-empty interface should print like an empty interface.
 	want := new(bytes.Buffer)
 	data := struct{ E interface{} }{}
 	tmpl.Execute(want, data)

 	if !bytes.Equal(want.Bytes(), got.Bytes()) {
 		t.Errorf("expected %q got %q", string(want.Bytes()), string(got.Bytes()))
 	}
 }
	// Copyright 2011 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 template

	import (
	"bytes"
	"fmt"
	"strings"
	"testing"
	)

	func TestTypedContent(t *testing.T) {
	data := []interface{}{
	`<b> "foo%" O'Reilly &bar;`,
	CSS(`a[href =~ "//example.com"]#foo`),
	HTML(`Hello, <b>World</b> &tc!`),
	HTMLAttr(` dir="ltr"`),
	JS(`c && alert("Hello, World!");`),
	JSStr(`Hello, World & O'Reilly\u0021`),
	URL(`greeting=H%69,&addressee=(World)`),
	Srcset(`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`),
	URL(`,foo/,`),
	}

	// For each content sensitive escaper, see how it does on
	// each of the typed strings above.
	tests := []struct {
	// A template containing a single {{.}}.
	input string
	want []string
	}{
	{
	`<style>{{.}} { color: blue }</style>`,
	[]string{
	`ZgotmplZ`,
	// Allowed but not escaped.
	`a[href =~ "//example.com"]#foo`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	},
	},
	{
	`<div style="{{.}}">`,
	[]string{
	`ZgotmplZ`,
	// Allowed and HTML escaped.
	`a[href =~ "//example.com"]#foo`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	},
	},
	{
	`{{.}}`,
	[]string{
	`<b> "foo%" O'Reilly &bar;`,
	`a[href =~ "//example.com"]#foo`,
	// Not escaped.
	`Hello, <b>World</b> &tc!`,
	` dir="ltr"`,
	`c && alert("Hello, World!");`,
	`Hello, World & O'Reilly\u0021`,
	`greeting=H%69,&addressee=(World)`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`,foo/,`,
	},
	},
	{
	`<a{{.}}>`,
	[]string{
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	// Allowed and HTML escaped.
	` dir="ltr"`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	`ZgotmplZ`,
	},
	},
	{
	`<a title={{.}}>`,
	[]string{
	`<b> "foo%" O'Reilly &bar;`,
	`a[href =~ "//example.com"]#foo`,
	// Tags stripped, spaces escaped, entity not re-escaped.
	`Hello, World &tc!`,
	` dir="ltr"`,
	`c && alert("Hello, World!");`,
	`Hello, World & O'Reilly\u0021`,
	`greeting=H%69,&addressee=(World)`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`,foo/,`,
	},
	},
	{
	`<a title='{{.}}'>`,
	[]string{
	`<b> "foo%" O'Reilly &bar;`,
	`a[href =~ "//example.com"]#foo`,
	// Tags stripped, entity not re-escaped.
	`Hello, World &tc!`,
	` dir="ltr"`,
	`c && alert("Hello, World!");`,
	`Hello, World & O'Reilly\u0021`,
	`greeting=H%69,&addressee=(World)`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`,foo/,`,
	},
	},
	{
	`<textarea>{{.}}</textarea>`,
	[]string{
	`<b> "foo%" O'Reilly &bar;`,
	`a[href =~ "//example.com"]#foo`,
	// Angle brackets escaped to prevent injection of close tags, entity not re-escaped.
	`Hello, <b>World</b> &tc!`,
	` dir="ltr"`,
	`c && alert("Hello, World!");`,
	`Hello, World & O'Reilly\u0021`,
	`greeting=H%69,&addressee=(World)`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`,foo/,`,
	},
	},
	{
	`<script>alert({{.}})</script>`,
	[]string{
	`"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`,
	`"a[href =~ \"//example.com\"]#foo"`,
	`"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`,
	`" dir=\"ltr\""`,
	// Not escaped.
	`c && alert("Hello, World!");`,
	// Escape sequence not over-escaped.
	`"Hello, World & O'Reilly\u0021"`,
	`"greeting=H%69,\u0026addressee=(World)"`,
	`"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`,
	`",foo/,"`,
	},
	},
	{
	`<button onclick="alert({{.}})">`,
	[]string{
	`"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`,
	`"a[href =~ \"//example.com\"]#foo"`,
	`"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`,
	`" dir=\"ltr\""`,
	// Not JS escaped but HTML escaped.
	`c && alert("Hello, World!");`,
	// Escape sequence not over-escaped.
	`"Hello, World & O'Reilly\u0021"`,
	`"greeting=H%69,\u0026addressee=(World)"`,
	`"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`,
	`",foo/,"`,
	},
	},
	{
	`<script>alert("{{.}}")</script>`,
	[]string{
	`\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`,
	`a[href =~ \u0022\/\/example.com\u0022]#foo`,
	`Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`,
	` dir=\u0022ltr\u0022`,
	`c \u0026\u0026 alert(\u0022Hello, World!\u0022);`,
	// Escape sequence not over-escaped.
	`Hello, World \u0026 O\u0027Reilly\u0021`,
	`greeting=H%69,\u0026addressee=(World)`,
	`greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`,
	`,foo\/,`,
	},
	},
	{
	`<script type="text/javascript">alert("{{.}}")</script>`,
	[]string{
	`\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`,
	`a[href =~ \u0022\/\/example.com\u0022]#foo`,
	`Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`,
	` dir=\u0022ltr\u0022`,
	`c \u0026\u0026 alert(\u0022Hello, World!\u0022);`,
	// Escape sequence not over-escaped.
	`Hello, World \u0026 O\u0027Reilly\u0021`,
	`greeting=H%69,\u0026addressee=(World)`,
	`greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`,
	`,foo\/,`,
	},
	},
	{
	`<script type="text/javascript">alert({{.}})</script>`,
	[]string{
	`"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`,
	`"a[href =~ \"//example.com\"]#foo"`,
	`"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`,
	`" dir=\"ltr\""`,
	// Not escaped.
	`c && alert("Hello, World!");`,
	// Escape sequence not over-escaped.
	`"Hello, World & O'Reilly\u0021"`,
	`"greeting=H%69,\u0026addressee=(World)"`,
	`"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`,
	`",foo/,"`,
	},
	},
	{
	// Not treated as JS. The output is same as for <div>{{.}}</div>
	`<script type="golang.org/x/website/go.dev/cmd/internal/text/template">{{.}}</script>`,
	[]string{
	`<b> "foo%" O'Reilly &bar;`,
	`a[href =~ "//example.com"]#foo`,
	// Not escaped.
	`Hello, <b>World</b> &tc!`,
	` dir="ltr"`,
	`c && alert("Hello, World!");`,
	`Hello, World & O'Reilly\u0021`,
	`greeting=H%69,&addressee=(World)`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`,foo/,`,
	},
	},
	{
	`<button onclick='alert("{{.}}")'>`,
	[]string{
	`\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`,
	`a[href =~ \u0022\/\/example.com\u0022]#foo`,
	`Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`,
	` dir=\u0022ltr\u0022`,
	`c \u0026\u0026 alert(\u0022Hello, World!\u0022);`,
	// Escape sequence not over-escaped.
	`Hello, World \u0026 O\u0027Reilly\u0021`,
	`greeting=H%69,\u0026addressee=(World)`,
	`greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`,
	`,foo\/,`,
	},
	},
	{
	`<a href="?q={{.}}">`,
	[]string{
	`%3cb%3e%20%22foo%25%22%20O%27Reilly%20%26bar%3b`,
	`a%5bhref%20%3d~%20%22%2f%2fexample.com%22%5d%23foo`,
	`Hello%2c%20%3cb%3eWorld%3c%2fb%3e%20%26amp%3btc%21`,
	`%20dir%3d%22ltr%22`,
	`c%20%26%26%20alert%28%22Hello%2c%20World%21%22%29%3b`,
	`Hello%2c%20World%20%26%20O%27Reilly%5cu0021`,
	// Quotes and parens are escaped but %69 is not over-escaped. HTML escaping is done.
	`greeting=H%69,&addressee=%28World%29`,
	`greeting%3dH%2569%2c%26addressee%3d%28World%29%202x%2c%20https%3a%2f%2fgolang.org%2ffavicon.ico%20500.5w`,
	`,foo/,`,
	},
	},
	{
	`<style>body { background: url('?img={{.}}') }</style>`,
	[]string{
	`%3cb%3e%20%22foo%25%22%20O%27Reilly%20%26bar%3b`,
	`a%5bhref%20%3d~%20%22%2f%2fexample.com%22%5d%23foo`,
	`Hello%2c%20%3cb%3eWorld%3c%2fb%3e%20%26amp%3btc%21`,
	`%20dir%3d%22ltr%22`,
	`c%20%26%26%20alert%28%22Hello%2c%20World%21%22%29%3b`,
	`Hello%2c%20World%20%26%20O%27Reilly%5cu0021`,
	// Quotes and parens are escaped but %69 is not over-escaped. HTML escaping is not done.
	`greeting=H%69,&addressee=%28World%29`,
	`greeting%3dH%2569%2c%26addressee%3d%28World%29%202x%2c%20https%3a%2f%2fgolang.org%2ffavicon.ico%20500.5w`,
	`,foo/,`,
	},
	},
	{
	`<img srcset="{{.}}">`,
	[]string{
	`#ZgotmplZ`,
	`#ZgotmplZ`,
	// Commas are not esacped
	`Hello,#ZgotmplZ`,
	// Leading spaces are not percent escapes.
	` dir=%22ltr%22`,
	// Spaces after commas are not percent escaped.
	`#ZgotmplZ, World!%22%29;`,
	`Hello,#ZgotmplZ`,
	`greeting=H%69%2c&addressee=%28World%29`,
	// Metadata is not escaped.
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`%2cfoo/%2c`,
	},
	},
	{
	`<img srcset={{.}}>`,
	[]string{
	`#ZgotmplZ`,
	`#ZgotmplZ`,
	`Hello,#ZgotmplZ`,
	// Spaces are HTML escaped not %-escaped
	` dir=%22ltr%22`,
	`#ZgotmplZ, World!%22%29;`,
	`Hello,#ZgotmplZ`,
	`greeting=H%69%2c&addressee=%28World%29`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	// Commas are escaped.
	`%2cfoo/%2c`,
	},
	},
	{
	`<img srcset="{{.}} 2x, https://golang.org/ 500.5w">`,
	[]string{
	`#ZgotmplZ`,
	`#ZgotmplZ`,
	`Hello,#ZgotmplZ`,
	` dir=%22ltr%22`,
	`#ZgotmplZ, World!%22%29;`,
	`Hello,#ZgotmplZ`,
	`greeting=H%69%2c&addressee=%28World%29`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`%2cfoo/%2c`,
	},
	},
	{
	`<img srcset="http://godoc.org/ {{.}}, https://golang.org/ 500.5w">`,
	[]string{
	`#ZgotmplZ`,
	`#ZgotmplZ`,
	`Hello,#ZgotmplZ`,
	` dir=%22ltr%22`,
	`#ZgotmplZ, World!%22%29;`,
	`Hello,#ZgotmplZ`,
	`greeting=H%69%2c&addressee=%28World%29`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`%2cfoo/%2c`,
	},
	},
	{
	`<img srcset="http://godoc.org/?q={{.}} 2x, https://golang.org/ 500.5w">`,
	[]string{
	`#ZgotmplZ`,
	`#ZgotmplZ`,
	`Hello,#ZgotmplZ`,
	` dir=%22ltr%22`,
	`#ZgotmplZ, World!%22%29;`,
	`Hello,#ZgotmplZ`,
	`greeting=H%69%2c&addressee=%28World%29`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`%2cfoo/%2c`,
	},
	},
	{
	`<img srcset="http://godoc.org/ 2x, {{.}} 500.5w">`,
	[]string{
	`#ZgotmplZ`,
	`#ZgotmplZ`,
	`Hello,#ZgotmplZ`,
	` dir=%22ltr%22`,
	`#ZgotmplZ, World!%22%29;`,
	`Hello,#ZgotmplZ`,
	`greeting=H%69%2c&addressee=%28World%29`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`%2cfoo/%2c`,
	},
	},
	{
	`<img srcset="http://godoc.org/ 2x, https://golang.org/ {{.}}">`,
	[]string{
	`#ZgotmplZ`,
	`#ZgotmplZ`,
	`Hello,#ZgotmplZ`,
	` dir=%22ltr%22`,
	`#ZgotmplZ, World!%22%29;`,
	`Hello,#ZgotmplZ`,
	`greeting=H%69%2c&addressee=%28World%29`,
	`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`,
	`%2cfoo/%2c`,
	},
	},
	}

	for _, test := range tests {
	tmpl := Must(New("x").Parse(test.input))
	pre := strings.Index(test.input, "{{.}}")
	post := len(test.input) - (pre + 5)
	var b bytes.Buffer
	for i, x := range data {
	b.Reset()
	if err := tmpl.Execute(&b, x); err != nil {
	t.Errorf("%q with %v: %s", test.input, x, err)
	continue
	}
	if want, got := test.want[i], b.String()[pre:b.Len()-post]; want != got {
	t.Errorf("%q with %v:\nwant\n\t%q,\ngot\n\t%q\n", test.input, x, want, got)
	continue
	}
	}
	}
	}

	// Test that we print using the String method. Was issue 3073.
	type myStringer struct {
	v int
	}

	func (s *myStringer) String() string {
	return fmt.Sprintf("string=%d", s.v)
	}

	type errorer struct {
	v int
	}

	func (s *errorer) Error() string {
	return fmt.Sprintf("error=%d", s.v)
	}

	func TestStringer(t *testing.T) {
	s := &myStringer{3}
	b := new(bytes.Buffer)
	tmpl := Must(New("x").Parse("{{.}}"))
	if err := tmpl.Execute(b, s); err != nil {
	t.Fatal(err)
	}
	var expect = "string=3"
	if b.String() != expect {
	t.Errorf("expected %q got %q", expect, b.String())
	}
	e := &errorer{7}
	b.Reset()
	if err := tmpl.Execute(b, e); err != nil {
	t.Fatal(err)
	}
	expect = "error=7"
	if b.String() != expect {
	t.Errorf("expected %q got %q", expect, b.String())
	}
	}

	// https://golang.org/issue/5982
	func TestEscapingNilNonemptyInterfaces(t *testing.T) {
	tmpl := Must(New("x").Parse("{{.E}}"))

	got := new(bytes.Buffer)
	testData := struct{ E error }{} // any non-empty interface here will do; error is just ready at hand
	tmpl.Execute(got, testData)

	// A non-empty interface should print like an empty interface.
	want := new(bytes.Buffer)
	data := struct{ E interface{} }{}
	tmpl.Execute(want, data)

	if !bytes.Equal(want.Bytes(), got.Bytes()) {
	t.Errorf("expected %q got %q", string(want.Bytes()), string(got.Bytes()))
	}
	}