Source file src/html/template/exec_test.go

Documentation: html/template

		 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  // Tests for template execution, copied from text/template.
		 6  
		 7  package template
		 8  
		 9  import (
		10  	"bytes"
		11  	"errors"
		12  	"flag"
		13  	"fmt"
		14  	"io"
		15  	"reflect"
		16  	"strings"
		17  	"sync"
		18  	"testing"
		19  	"text/template"
		20  )
		21  
		22  var debug = flag.Bool("debug", false, "show the errors produced by the tests")
		23  
		24  // T has lots of interesting pieces to use to test execution.
		25  type T struct {
		26  	// Basics
		27  	True				bool
		28  	I					 int
		29  	U16				 uint16
		30  	X, S				string
		31  	FloatZero	 float64
		32  	ComplexZero complex128
		33  	// Nested structs.
		34  	U *U
		35  	// Struct with String method.
		36  	V0		 V
		37  	V1, V2 *V
		38  	// Struct with Error method.
		39  	W0		 W
		40  	W1, W2 *W
		41  	// Slices
		42  	SI			[]int
		43  	SICap	 []int
		44  	SIEmpty []int
		45  	SB			[]bool
		46  	// Arrays
		47  	AI [3]int
		48  	// Maps
		49  	MSI			map[string]int
		50  	MSIone	 map[string]int // one element, for deterministic output
		51  	MSIEmpty map[string]int
		52  	MXI			map[interface{}]int
		53  	MII			map[int]int
		54  	MI32S		map[int32]string
		55  	MI64S		map[int64]string
		56  	MUI32S	 map[uint32]string
		57  	MUI64S	 map[uint64]string
		58  	MI8S		 map[int8]string
		59  	MUI8S		map[uint8]string
		60  	SMSI		 []map[string]int
		61  	// Empty interfaces; used to see if we can dig inside one.
		62  	Empty0 interface{} // nil
		63  	Empty1 interface{}
		64  	Empty2 interface{}
		65  	Empty3 interface{}
		66  	Empty4 interface{}
		67  	// Non-empty interfaces.
		68  	NonEmptyInterface				 I
		69  	NonEmptyInterfacePtS			*I
		70  	NonEmptyInterfaceNil			I
		71  	NonEmptyInterfaceTypedNil I
		72  	// Stringer.
		73  	Str fmt.Stringer
		74  	Err error
		75  	// Pointers
		76  	PI	*int
		77  	PS	*string
		78  	PSI *[]int
		79  	NIL *int
		80  	// Function (not method)
		81  	BinaryFunc			func(string, string) string
		82  	VariadicFunc		func(...string) string
		83  	VariadicFuncInt func(int, ...string) string
		84  	NilOKFunc			 func(*int) bool
		85  	ErrFunc				 func() (string, error)
		86  	PanicFunc			 func() string
		87  	// Template to test evaluation of templates.
		88  	Tmpl *Template
		89  	// Unexported field; cannot be accessed by template.
		90  	unexported int
		91  }
		92  
		93  type S []string
		94  
		95  func (S) Method0() string {
		96  	return "M0"
		97  }
		98  
		99  type U struct {
	 100  	V string
	 101  }
	 102  
	 103  type V struct {
	 104  	j int
	 105  }
	 106  
	 107  func (v *V) String() string {
	 108  	if v == nil {
	 109  		return "nilV"
	 110  	}
	 111  	return fmt.Sprintf("<%d>", v.j)
	 112  }
	 113  
	 114  type W struct {
	 115  	k int
	 116  }
	 117  
	 118  func (w *W) Error() string {
	 119  	if w == nil {
	 120  		return "nilW"
	 121  	}
	 122  	return fmt.Sprintf("[%d]", w.k)
	 123  }
	 124  
	 125  var siVal = I(S{"a", "b"})
	 126  
	 127  var tVal = &T{
	 128  	True:	 true,
	 129  	I:			17,
	 130  	U16:		16,
	 131  	X:			"x",
	 132  	S:			"xyz",
	 133  	U:			&U{"v"},
	 134  	V0:		 V{6666},
	 135  	V1:		 &V{7777}, // leave V2 as nil
	 136  	W0:		 W{888},
	 137  	W1:		 &W{999}, // leave W2 as nil
	 138  	SI:		 []int{3, 4, 5},
	 139  	SICap:	make([]int, 5, 10),
	 140  	AI:		 [3]int{3, 4, 5},
	 141  	SB:		 []bool{true, false},
	 142  	MSI:		map[string]int{"one": 1, "two": 2, "three": 3},
	 143  	MSIone: map[string]int{"one": 1},
	 144  	MXI:		map[interface{}]int{"one": 1},
	 145  	MII:		map[int]int{1: 1},
	 146  	MI32S:	map[int32]string{1: "one", 2: "two"},
	 147  	MI64S:	map[int64]string{2: "i642", 3: "i643"},
	 148  	MUI32S: map[uint32]string{2: "u322", 3: "u323"},
	 149  	MUI64S: map[uint64]string{2: "ui642", 3: "ui643"},
	 150  	MI8S:	 map[int8]string{2: "i82", 3: "i83"},
	 151  	MUI8S:	map[uint8]string{2: "u82", 3: "u83"},
	 152  	SMSI: []map[string]int{
	 153  		{"one": 1, "two": 2},
	 154  		{"eleven": 11, "twelve": 12},
	 155  	},
	 156  	Empty1:										3,
	 157  	Empty2:										"empty2",
	 158  	Empty3:										[]int{7, 8},
	 159  	Empty4:										&U{"UinEmpty"},
	 160  	NonEmptyInterface:				 &T{X: "x"},
	 161  	NonEmptyInterfacePtS:			&siVal,
	 162  	NonEmptyInterfaceTypedNil: (*T)(nil),
	 163  	Str:											 bytes.NewBuffer([]byte("foozle")),
	 164  	Err:											 errors.New("erroozle"),
	 165  	PI:												newInt(23),
	 166  	PS:												newString("a string"),
	 167  	PSI:											 newIntSlice(21, 22, 23),
	 168  	BinaryFunc:								func(a, b string) string { return fmt.Sprintf("[%s=%s]", a, b) },
	 169  	VariadicFunc:							func(s ...string) string { return fmt.Sprint("<", strings.Join(s, "+"), ">") },
	 170  	VariadicFuncInt:					 func(a int, s ...string) string { return fmt.Sprint(a, "=<", strings.Join(s, "+"), ">") },
	 171  	NilOKFunc:								 func(s *int) bool { return s == nil },
	 172  	ErrFunc:									 func() (string, error) { return "bla", nil },
	 173  	PanicFunc:								 func() string { panic("test panic") },
	 174  	Tmpl:											Must(New("x").Parse("test template")), // "x" is the value of .X
	 175  }
	 176  
	 177  var tSliceOfNil = []*T{nil}
	 178  
	 179  // A non-empty interface.
	 180  type I interface {
	 181  	Method0() string
	 182  }
	 183  
	 184  var iVal I = tVal
	 185  
	 186  // Helpers for creation.
	 187  func newInt(n int) *int {
	 188  	return &n
	 189  }
	 190  
	 191  func newString(s string) *string {
	 192  	return &s
	 193  }
	 194  
	 195  func newIntSlice(n ...int) *[]int {
	 196  	p := new([]int)
	 197  	*p = make([]int, len(n))
	 198  	copy(*p, n)
	 199  	return p
	 200  }
	 201  
	 202  // Simple methods with and without arguments.
	 203  func (t *T) Method0() string {
	 204  	return "M0"
	 205  }
	 206  
	 207  func (t *T) Method1(a int) int {
	 208  	return a
	 209  }
	 210  
	 211  func (t *T) Method2(a uint16, b string) string {
	 212  	return fmt.Sprintf("Method2: %d %s", a, b)
	 213  }
	 214  
	 215  func (t *T) Method3(v interface{}) string {
	 216  	return fmt.Sprintf("Method3: %v", v)
	 217  }
	 218  
	 219  func (t *T) Copy() *T {
	 220  	n := new(T)
	 221  	*n = *t
	 222  	return n
	 223  }
	 224  
	 225  func (t *T) MAdd(a int, b []int) []int {
	 226  	v := make([]int, len(b))
	 227  	for i, x := range b {
	 228  		v[i] = x + a
	 229  	}
	 230  	return v
	 231  }
	 232  
	 233  var myError = errors.New("my error")
	 234  
	 235  // MyError returns a value and an error according to its argument.
	 236  func (t *T) MyError(error bool) (bool, error) {
	 237  	if error {
	 238  		return true, myError
	 239  	}
	 240  	return false, nil
	 241  }
	 242  
	 243  // A few methods to test chaining.
	 244  func (t *T) GetU() *U {
	 245  	return t.U
	 246  }
	 247  
	 248  func (u *U) TrueFalse(b bool) string {
	 249  	if b {
	 250  		return "true"
	 251  	}
	 252  	return ""
	 253  }
	 254  
	 255  func typeOf(arg interface{}) string {
	 256  	return fmt.Sprintf("%T", arg)
	 257  }
	 258  
	 259  type execTest struct {
	 260  	name	 string
	 261  	input	string
	 262  	output string
	 263  	data	 interface{}
	 264  	ok		 bool
	 265  }
	 266  
	 267  // bigInt and bigUint are hex string representing numbers either side
	 268  // of the max int boundary.
	 269  // We do it this way so the test doesn't depend on ints being 32 bits.
	 270  var (
	 271  	bigInt	= fmt.Sprintf("0x%x", int(1<<uint(reflect.TypeOf(0).Bits()-1)-1))
	 272  	bigUint = fmt.Sprintf("0x%x", uint(1<<uint(reflect.TypeOf(0).Bits()-1)))
	 273  )
	 274  
	 275  var execTests = []execTest{
	 276  	// Trivial cases.
	 277  	{"empty", "", "", nil, true},
	 278  	{"text", "some text", "some text", nil, true},
	 279  	{"nil action", "{{nil}}", "", nil, false},
	 280  
	 281  	// Ideal constants.
	 282  	{"ideal int", "{{typeOf 3}}", "int", 0, true},
	 283  	{"ideal float", "{{typeOf 1.0}}", "float64", 0, true},
	 284  	{"ideal exp float", "{{typeOf 1e1}}", "float64", 0, true},
	 285  	{"ideal complex", "{{typeOf 1i}}", "complex128", 0, true},
	 286  	{"ideal int", "{{typeOf " + bigInt + "}}", "int", 0, true},
	 287  	{"ideal too big", "{{typeOf " + bigUint + "}}", "", 0, false},
	 288  	{"ideal nil without type", "{{nil}}", "", 0, false},
	 289  
	 290  	// Fields of structs.
	 291  	{".X", "-{{.X}}-", "-x-", tVal, true},
	 292  	{".U.V", "-{{.U.V}}-", "-v-", tVal, true},
	 293  	{".unexported", "{{.unexported}}", "", tVal, false},
	 294  
	 295  	// Fields on maps.
	 296  	{"map .one", "{{.MSI.one}}", "1", tVal, true},
	 297  	{"map .two", "{{.MSI.two}}", "2", tVal, true},
	 298  	{"map .NO", "{{.MSI.NO}}", "", tVal, true}, // NOTE: <no value> in text/template
	 299  	{"map .one interface", "{{.MXI.one}}", "1", tVal, true},
	 300  	{"map .WRONG args", "{{.MSI.one 1}}", "", tVal, false},
	 301  	{"map .WRONG type", "{{.MII.one}}", "", tVal, false},
	 302  
	 303  	// Dots of all kinds to test basic evaluation.
	 304  	{"dot int", "<{{.}}>", "&lt;13>", 13, true},
	 305  	{"dot uint", "<{{.}}>", "&lt;14>", uint(14), true},
	 306  	{"dot float", "<{{.}}>", "&lt;15.1>", 15.1, true},
	 307  	{"dot bool", "<{{.}}>", "&lt;true>", true, true},
	 308  	{"dot complex", "<{{.}}>", "&lt;(16.2-17i)>", 16.2 - 17i, true},
	 309  	{"dot string", "<{{.}}>", "&lt;hello>", "hello", true},
	 310  	{"dot slice", "<{{.}}>", "&lt;[-1 -2 -3]>", []int{-1, -2, -3}, true},
	 311  	{"dot map", "<{{.}}>", "&lt;map[two:22]>", map[string]int{"two": 22}, true},
	 312  	{"dot struct", "<{{.}}>", "&lt;{7 seven}>", struct {
	 313  		a int
	 314  		b string
	 315  	}{7, "seven"}, true},
	 316  
	 317  	// Variables.
	 318  	{"$ int", "{{$}}", "123", 123, true},
	 319  	{"$.I", "{{$.I}}", "17", tVal, true},
	 320  	{"$.U.V", "{{$.U.V}}", "v", tVal, true},
	 321  	{"declare in action", "{{$x := $.U.V}}{{$x}}", "v", tVal, true},
	 322  	{"simple assignment", "{{$x := 2}}{{$x = 3}}{{$x}}", "3", tVal, true},
	 323  	{"nested assignment",
	 324  		"{{$x := 2}}{{if true}}{{$x = 3}}{{end}}{{$x}}",
	 325  		"3", tVal, true},
	 326  	{"nested assignment changes the last declaration",
	 327  		"{{$x := 1}}{{if true}}{{$x := 2}}{{if true}}{{$x = 3}}{{end}}{{end}}{{$x}}",
	 328  		"1", tVal, true},
	 329  
	 330  	// Type with String method.
	 331  	{"V{6666}.String()", "-{{.V0}}-", "-{6666}-", tVal, true}, //	NOTE: -<6666>- in text/template
	 332  	{"&V{7777}.String()", "-{{.V1}}-", "-&lt;7777&gt;-", tVal, true},
	 333  	{"(*V)(nil).String()", "-{{.V2}}-", "-nilV-", tVal, true},
	 334  
	 335  	// Type with Error method.
	 336  	{"W{888}.Error()", "-{{.W0}}-", "-{888}-", tVal, true}, // NOTE: -[888] in text/template
	 337  	{"&W{999}.Error()", "-{{.W1}}-", "-[999]-", tVal, true},
	 338  	{"(*W)(nil).Error()", "-{{.W2}}-", "-nilW-", tVal, true},
	 339  
	 340  	// Pointers.
	 341  	{"*int", "{{.PI}}", "23", tVal, true},
	 342  	{"*string", "{{.PS}}", "a string", tVal, true},
	 343  	{"*[]int", "{{.PSI}}", "[21 22 23]", tVal, true},
	 344  	{"*[]int[1]", "{{index .PSI 1}}", "22", tVal, true},
	 345  	{"NIL", "{{.NIL}}", "&lt;nil&gt;", tVal, true},
	 346  
	 347  	// Empty interfaces holding values.
	 348  	{"empty nil", "{{.Empty0}}", "", tVal, true}, // NOTE: <no value> in text/template
	 349  	{"empty with int", "{{.Empty1}}", "3", tVal, true},
	 350  	{"empty with string", "{{.Empty2}}", "empty2", tVal, true},
	 351  	{"empty with slice", "{{.Empty3}}", "[7 8]", tVal, true},
	 352  	{"empty with struct", "{{.Empty4}}", "{UinEmpty}", tVal, true},
	 353  	{"empty with struct, field", "{{.Empty4.V}}", "UinEmpty", tVal, true},
	 354  
	 355  	// Edge cases with <no value> with an interface value
	 356  	{"field on interface", "{{.foo}}", "", nil, true},									// NOTE: <no value> in text/template
	 357  	{"field on parenthesized interface", "{{(.).foo}}", "", nil, true}, // NOTE: <no value> in text/template
	 358  
	 359  	// Issue 31810: Parenthesized first element of pipeline with arguments.
	 360  	// See also TestIssue31810.
	 361  	{"unparenthesized non-function", "{{1 2}}", "", nil, false},
	 362  	{"parenthesized non-function", "{{(1) 2}}", "", nil, false},
	 363  	{"parenthesized non-function with no args", "{{(1)}}", "1", nil, true}, // This is fine.
	 364  
	 365  	// Method calls.
	 366  	{".Method0", "-{{.Method0}}-", "-M0-", tVal, true},
	 367  	{".Method1(1234)", "-{{.Method1 1234}}-", "-1234-", tVal, true},
	 368  	{".Method1(.I)", "-{{.Method1 .I}}-", "-17-", tVal, true},
	 369  	{".Method2(3, .X)", "-{{.Method2 3 .X}}-", "-Method2: 3 x-", tVal, true},
	 370  	{".Method2(.U16, `str`)", "-{{.Method2 .U16 `str`}}-", "-Method2: 16 str-", tVal, true},
	 371  	{".Method2(.U16, $x)", "{{if $x := .X}}-{{.Method2 .U16 $x}}{{end}}-", "-Method2: 16 x-", tVal, true},
	 372  	{".Method3(nil constant)", "-{{.Method3 nil}}-", "-Method3: &lt;nil&gt;-", tVal, true},
	 373  	{".Method3(nil value)", "-{{.Method3 .MXI.unset}}-", "-Method3: &lt;nil&gt;-", tVal, true},
	 374  	{"method on var", "{{if $x := .}}-{{$x.Method2 .U16 $x.X}}{{end}}-", "-Method2: 16 x-", tVal, true},
	 375  	{"method on chained var",
	 376  		"{{range .MSIone}}{{if $.U.TrueFalse $.True}}{{$.U.TrueFalse $.True}}{{else}}WRONG{{end}}{{end}}",
	 377  		"true", tVal, true},
	 378  	{"chained method",
	 379  		"{{range .MSIone}}{{if $.GetU.TrueFalse $.True}}{{$.U.TrueFalse $.True}}{{else}}WRONG{{end}}{{end}}",
	 380  		"true", tVal, true},
	 381  	{"chained method on variable",
	 382  		"{{with $x := .}}{{with .SI}}{{$.GetU.TrueFalse $.True}}{{end}}{{end}}",
	 383  		"true", tVal, true},
	 384  	{".NilOKFunc not nil", "{{call .NilOKFunc .PI}}", "false", tVal, true},
	 385  	{".NilOKFunc nil", "{{call .NilOKFunc nil}}", "true", tVal, true},
	 386  	{"method on nil value from slice", "-{{range .}}{{.Method1 1234}}{{end}}-", "-1234-", tSliceOfNil, true},
	 387  	{"method on typed nil interface value", "{{.NonEmptyInterfaceTypedNil.Method0}}", "M0", tVal, true},
	 388  
	 389  	// Function call builtin.
	 390  	{".BinaryFunc", "{{call .BinaryFunc `1` `2`}}", "[1=2]", tVal, true},
	 391  	{".VariadicFunc0", "{{call .VariadicFunc}}", "&lt;&gt;", tVal, true},
	 392  	{".VariadicFunc2", "{{call .VariadicFunc `he` `llo`}}", "&lt;he&#43;llo&gt;", tVal, true},
	 393  	{".VariadicFuncInt", "{{call .VariadicFuncInt 33 `he` `llo`}}", "33=&lt;he&#43;llo&gt;", tVal, true},
	 394  	{"if .BinaryFunc call", "{{ if .BinaryFunc}}{{call .BinaryFunc `1` `2`}}{{end}}", "[1=2]", tVal, true},
	 395  	{"if not .BinaryFunc call", "{{ if not .BinaryFunc}}{{call .BinaryFunc `1` `2`}}{{else}}No{{end}}", "No", tVal, true},
	 396  	{"Interface Call", `{{stringer .S}}`, "foozle", map[string]interface{}{"S": bytes.NewBufferString("foozle")}, true},
	 397  	{".ErrFunc", "{{call .ErrFunc}}", "bla", tVal, true},
	 398  	{"call nil", "{{call nil}}", "", tVal, false},
	 399  
	 400  	// Erroneous function calls (check args).
	 401  	{".BinaryFuncTooFew", "{{call .BinaryFunc `1`}}", "", tVal, false},
	 402  	{".BinaryFuncTooMany", "{{call .BinaryFunc `1` `2` `3`}}", "", tVal, false},
	 403  	{".BinaryFuncBad0", "{{call .BinaryFunc 1 3}}", "", tVal, false},
	 404  	{".BinaryFuncBad1", "{{call .BinaryFunc `1` 3}}", "", tVal, false},
	 405  	{".VariadicFuncBad0", "{{call .VariadicFunc 3}}", "", tVal, false},
	 406  	{".VariadicFuncIntBad0", "{{call .VariadicFuncInt}}", "", tVal, false},
	 407  	{".VariadicFuncIntBad`", "{{call .VariadicFuncInt `x`}}", "", tVal, false},
	 408  	{".VariadicFuncNilBad", "{{call .VariadicFunc nil}}", "", tVal, false},
	 409  
	 410  	// Pipelines.
	 411  	{"pipeline", "-{{.Method0 | .Method2 .U16}}-", "-Method2: 16 M0-", tVal, true},
	 412  	{"pipeline func", "-{{call .VariadicFunc `llo` | call .VariadicFunc `he` }}-", "-&lt;he&#43;&lt;llo&gt;&gt;-", tVal, true},
	 413  
	 414  	// Nil values aren't missing arguments.
	 415  	{"nil pipeline", "{{ .Empty0 | call .NilOKFunc }}", "true", tVal, true},
	 416  	{"nil call arg", "{{ call .NilOKFunc .Empty0 }}", "true", tVal, true},
	 417  	{"bad nil pipeline", "{{ .Empty0 | .VariadicFunc }}", "", tVal, false},
	 418  
	 419  	// Parenthesized expressions
	 420  	{"parens in pipeline", "{{printf `%d %d %d` (1) (2 | add 3) (add 4 (add 5 6))}}", "1 5 15", tVal, true},
	 421  
	 422  	// Parenthesized expressions with field accesses
	 423  	{"parens: $ in paren", "{{($).X}}", "x", tVal, true},
	 424  	{"parens: $.GetU in paren", "{{($.GetU).V}}", "v", tVal, true},
	 425  	{"parens: $ in paren in pipe", "{{($ | echo).X}}", "x", tVal, true},
	 426  	{"parens: spaces and args", `{{(makemap "up" "down" "left" "right").left}}`, "right", tVal, true},
	 427  
	 428  	// If.
	 429  	{"if true", "{{if true}}TRUE{{end}}", "TRUE", tVal, true},
	 430  	{"if false", "{{if false}}TRUE{{else}}FALSE{{end}}", "FALSE", tVal, true},
	 431  	{"if nil", "{{if nil}}TRUE{{end}}", "", tVal, false},
	 432  	{"if on typed nil interface value", "{{if .NonEmptyInterfaceTypedNil}}TRUE{{ end }}", "", tVal, true},
	 433  	{"if 1", "{{if 1}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true},
	 434  	{"if 0", "{{if 0}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true},
	 435  	{"if 1.5", "{{if 1.5}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true},
	 436  	{"if 0.0", "{{if .FloatZero}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true},
	 437  	{"if 1.5i", "{{if 1.5i}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true},
	 438  	{"if 0.0i", "{{if .ComplexZero}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true},
	 439  	{"if emptystring", "{{if ``}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 440  	{"if string", "{{if `notempty`}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true},
	 441  	{"if emptyslice", "{{if .SIEmpty}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 442  	{"if slice", "{{if .SI}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true},
	 443  	{"if emptymap", "{{if .MSIEmpty}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 444  	{"if map", "{{if .MSI}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true},
	 445  	{"if map unset", "{{if .MXI.none}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true},
	 446  	{"if map not unset", "{{if not .MXI.none}}ZERO{{else}}NON-ZERO{{end}}", "ZERO", tVal, true},
	 447  	{"if $x with $y int", "{{if $x := true}}{{with $y := .I}}{{$x}},{{$y}}{{end}}{{end}}", "true,17", tVal, true},
	 448  	{"if $x with $x int", "{{if $x := true}}{{with $x := .I}}{{$x}},{{end}}{{$x}}{{end}}", "17,true", tVal, true},
	 449  	{"if else if", "{{if false}}FALSE{{else if true}}TRUE{{end}}", "TRUE", tVal, true},
	 450  	{"if else chain", "{{if eq 1 3}}1{{else if eq 2 3}}2{{else if eq 3 3}}3{{end}}", "3", tVal, true},
	 451  
	 452  	// Print etc.
	 453  	{"print", `{{print "hello, print"}}`, "hello, print", tVal, true},
	 454  	{"print 123", `{{print 1 2 3}}`, "1 2 3", tVal, true},
	 455  	{"print nil", `{{print nil}}`, "&lt;nil&gt;", tVal, true},
	 456  	{"println", `{{println 1 2 3}}`, "1 2 3\n", tVal, true},
	 457  	{"printf int", `{{printf "%04x" 127}}`, "007f", tVal, true},
	 458  	{"printf float", `{{printf "%g" 3.5}}`, "3.5", tVal, true},
	 459  	{"printf complex", `{{printf "%g" 1+7i}}`, "(1&#43;7i)", tVal, true},
	 460  	{"printf string", `{{printf "%s" "hello"}}`, "hello", tVal, true},
	 461  	{"printf function", `{{printf "%#q" zeroArgs}}`, "`zeroArgs`", tVal, true},
	 462  	{"printf field", `{{printf "%s" .U.V}}`, "v", tVal, true},
	 463  	{"printf method", `{{printf "%s" .Method0}}`, "M0", tVal, true},
	 464  	{"printf dot", `{{with .I}}{{printf "%d" .}}{{end}}`, "17", tVal, true},
	 465  	{"printf var", `{{with $x := .I}}{{printf "%d" $x}}{{end}}`, "17", tVal, true},
	 466  	{"printf lots", `{{printf "%d %s %g %s" 127 "hello" 7-3i .Method0}}`, "127 hello (7-3i) M0", tVal, true},
	 467  
	 468  	// HTML.
	 469  	{"html", `{{html "<script>alert(\"XSS\");</script>"}}`,
	 470  		"&lt;script&gt;alert(&#34;XSS&#34;);&lt;/script&gt;", nil, true},
	 471  	{"html pipeline", `{{printf "<script>alert(\"XSS\");</script>" | html}}`,
	 472  		"&lt;script&gt;alert(&#34;XSS&#34;);&lt;/script&gt;", nil, true},
	 473  	{"html", `{{html .PS}}`, "a string", tVal, true},
	 474  	{"html typed nil", `{{html .NIL}}`, "&lt;nil&gt;", tVal, true},
	 475  	{"html untyped nil", `{{html .Empty0}}`, "&lt;nil&gt;", tVal, true}, // NOTE: "&lt;no value&gt;" in text/template
	 476  
	 477  	// JavaScript.
	 478  	{"js", `{{js .}}`, `It\&#39;d be nice.`, `It'd be nice.`, true},
	 479  
	 480  	// URL query.
	 481  	{"urlquery", `{{"http://www.example.org/"|urlquery}}`, "http%3A%2F%2Fwww.example.org%2F", nil, true},
	 482  
	 483  	// Booleans
	 484  	{"not", "{{not true}} {{not false}}", "false true", nil, true},
	 485  	{"and", "{{and false 0}} {{and 1 0}} {{and 0 true}} {{and 1 1}}", "false 0 0 1", nil, true},
	 486  	{"or", "{{or 0 0}} {{or 1 0}} {{or 0 true}} {{or 1 1}}", "0 1 true 1", nil, true},
	 487  	{"boolean if", "{{if and true 1 `hi`}}TRUE{{else}}FALSE{{end}}", "TRUE", tVal, true},
	 488  	{"boolean if not", "{{if and true 1 `hi` | not}}TRUE{{else}}FALSE{{end}}", "FALSE", nil, true},
	 489  
	 490  	// Indexing.
	 491  	{"slice[0]", "{{index .SI 0}}", "3", tVal, true},
	 492  	{"slice[1]", "{{index .SI 1}}", "4", tVal, true},
	 493  	{"slice[HUGE]", "{{index .SI 10}}", "", tVal, false},
	 494  	{"slice[WRONG]", "{{index .SI `hello`}}", "", tVal, false},
	 495  	{"slice[nil]", "{{index .SI nil}}", "", tVal, false},
	 496  	{"map[one]", "{{index .MSI `one`}}", "1", tVal, true},
	 497  	{"map[two]", "{{index .MSI `two`}}", "2", tVal, true},
	 498  	{"map[NO]", "{{index .MSI `XXX`}}", "0", tVal, true},
	 499  	{"map[nil]", "{{index .MSI nil}}", "", tVal, false},
	 500  	{"map[``]", "{{index .MSI ``}}", "0", tVal, true},
	 501  	{"map[WRONG]", "{{index .MSI 10}}", "", tVal, false},
	 502  	{"double index", "{{index .SMSI 1 `eleven`}}", "11", tVal, true},
	 503  	{"nil[1]", "{{index nil 1}}", "", tVal, false},
	 504  	{"map MI64S", "{{index .MI64S 2}}", "i642", tVal, true},
	 505  	{"map MI32S", "{{index .MI32S 2}}", "two", tVal, true},
	 506  	{"map MUI64S", "{{index .MUI64S 3}}", "ui643", tVal, true},
	 507  	{"map MI8S", "{{index .MI8S 3}}", "i83", tVal, true},
	 508  	{"map MUI8S", "{{index .MUI8S 2}}", "u82", tVal, true},
	 509  	{"index of an interface field", "{{index .Empty3 0}}", "7", tVal, true},
	 510  
	 511  	// Slicing.
	 512  	{"slice[:]", "{{slice .SI}}", "[3 4 5]", tVal, true},
	 513  	{"slice[1:]", "{{slice .SI 1}}", "[4 5]", tVal, true},
	 514  	{"slice[1:2]", "{{slice .SI 1 2}}", "[4]", tVal, true},
	 515  	{"slice[-1:]", "{{slice .SI -1}}", "", tVal, false},
	 516  	{"slice[1:-2]", "{{slice .SI 1 -2}}", "", tVal, false},
	 517  	{"slice[1:2:-1]", "{{slice .SI 1 2 -1}}", "", tVal, false},
	 518  	{"slice[2:1]", "{{slice .SI 2 1}}", "", tVal, false},
	 519  	{"slice[2:2:1]", "{{slice .SI 2 2 1}}", "", tVal, false},
	 520  	{"out of range", "{{slice .SI 4 5}}", "", tVal, false},
	 521  	{"out of range", "{{slice .SI 2 2 5}}", "", tVal, false},
	 522  	{"len(s) < indexes < cap(s)", "{{slice .SICap 6 10}}", "[0 0 0 0]", tVal, true},
	 523  	{"len(s) < indexes < cap(s)", "{{slice .SICap 6 10 10}}", "[0 0 0 0]", tVal, true},
	 524  	{"indexes > cap(s)", "{{slice .SICap 10 11}}", "", tVal, false},
	 525  	{"indexes > cap(s)", "{{slice .SICap 6 10 11}}", "", tVal, false},
	 526  	{"array[:]", "{{slice .AI}}", "[3 4 5]", tVal, true},
	 527  	{"array[1:]", "{{slice .AI 1}}", "[4 5]", tVal, true},
	 528  	{"array[1:2]", "{{slice .AI 1 2}}", "[4]", tVal, true},
	 529  	{"string[:]", "{{slice .S}}", "xyz", tVal, true},
	 530  	{"string[0:1]", "{{slice .S 0 1}}", "x", tVal, true},
	 531  	{"string[1:]", "{{slice .S 1}}", "yz", tVal, true},
	 532  	{"string[1:2]", "{{slice .S 1 2}}", "y", tVal, true},
	 533  	{"out of range", "{{slice .S 1 5}}", "", tVal, false},
	 534  	{"3-index slice of string", "{{slice .S 1 2 2}}", "", tVal, false},
	 535  	{"slice of an interface field", "{{slice .Empty3 0 1}}", "[7]", tVal, true},
	 536  
	 537  	// Len.
	 538  	{"slice", "{{len .SI}}", "3", tVal, true},
	 539  	{"map", "{{len .MSI }}", "3", tVal, true},
	 540  	{"len of int", "{{len 3}}", "", tVal, false},
	 541  	{"len of nothing", "{{len .Empty0}}", "", tVal, false},
	 542  	{"len of an interface field", "{{len .Empty3}}", "2", tVal, true},
	 543  
	 544  	// With.
	 545  	{"with true", "{{with true}}{{.}}{{end}}", "true", tVal, true},
	 546  	{"with false", "{{with false}}{{.}}{{else}}FALSE{{end}}", "FALSE", tVal, true},
	 547  	{"with 1", "{{with 1}}{{.}}{{else}}ZERO{{end}}", "1", tVal, true},
	 548  	{"with 0", "{{with 0}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true},
	 549  	{"with 1.5", "{{with 1.5}}{{.}}{{else}}ZERO{{end}}", "1.5", tVal, true},
	 550  	{"with 0.0", "{{with .FloatZero}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true},
	 551  	{"with 1.5i", "{{with 1.5i}}{{.}}{{else}}ZERO{{end}}", "(0&#43;1.5i)", tVal, true},
	 552  	{"with 0.0i", "{{with .ComplexZero}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true},
	 553  	{"with emptystring", "{{with ``}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 554  	{"with string", "{{with `notempty`}}{{.}}{{else}}EMPTY{{end}}", "notempty", tVal, true},
	 555  	{"with emptyslice", "{{with .SIEmpty}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 556  	{"with slice", "{{with .SI}}{{.}}{{else}}EMPTY{{end}}", "[3 4 5]", tVal, true},
	 557  	{"with emptymap", "{{with .MSIEmpty}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 558  	{"with map", "{{with .MSIone}}{{.}}{{else}}EMPTY{{end}}", "map[one:1]", tVal, true},
	 559  	{"with empty interface, struct field", "{{with .Empty4}}{{.V}}{{end}}", "UinEmpty", tVal, true},
	 560  	{"with $x int", "{{with $x := .I}}{{$x}}{{end}}", "17", tVal, true},
	 561  	{"with $x struct.U.V", "{{with $x := $}}{{$x.U.V}}{{end}}", "v", tVal, true},
	 562  	{"with variable and action", "{{with $x := $}}{{$y := $.U.V}}{{$y}}{{end}}", "v", tVal, true},
	 563  	{"with on typed nil interface value", "{{with .NonEmptyInterfaceTypedNil}}TRUE{{ end }}", "", tVal, true},
	 564  
	 565  	// Range.
	 566  	{"range []int", "{{range .SI}}-{{.}}-{{end}}", "-3--4--5-", tVal, true},
	 567  	{"range empty no else", "{{range .SIEmpty}}-{{.}}-{{end}}", "", tVal, true},
	 568  	{"range []int else", "{{range .SI}}-{{.}}-{{else}}EMPTY{{end}}", "-3--4--5-", tVal, true},
	 569  	{"range empty else", "{{range .SIEmpty}}-{{.}}-{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 570  	{"range []bool", "{{range .SB}}-{{.}}-{{end}}", "-true--false-", tVal, true},
	 571  	{"range []int method", "{{range .SI | .MAdd .I}}-{{.}}-{{end}}", "-20--21--22-", tVal, true},
	 572  	{"range map", "{{range .MSI}}-{{.}}-{{end}}", "-1--3--2-", tVal, true},
	 573  	{"range empty map no else", "{{range .MSIEmpty}}-{{.}}-{{end}}", "", tVal, true},
	 574  	{"range map else", "{{range .MSI}}-{{.}}-{{else}}EMPTY{{end}}", "-1--3--2-", tVal, true},
	 575  	{"range empty map else", "{{range .MSIEmpty}}-{{.}}-{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
	 576  	{"range empty interface", "{{range .Empty3}}-{{.}}-{{else}}EMPTY{{end}}", "-7--8-", tVal, true},
	 577  	{"range empty nil", "{{range .Empty0}}-{{.}}-{{end}}", "", tVal, true},
	 578  	{"range $x SI", "{{range $x := .SI}}<{{$x}}>{{end}}", "&lt;3>&lt;4>&lt;5>", tVal, true},
	 579  	{"range $x $y SI", "{{range $x, $y := .SI}}<{{$x}}={{$y}}>{{end}}", "&lt;0=3>&lt;1=4>&lt;2=5>", tVal, true},
	 580  	{"range $x MSIone", "{{range $x := .MSIone}}<{{$x}}>{{end}}", "&lt;1>", tVal, true},
	 581  	{"range $x $y MSIone", "{{range $x, $y := .MSIone}}<{{$x}}={{$y}}>{{end}}", "&lt;one=1>", tVal, true},
	 582  	{"range $x PSI", "{{range $x := .PSI}}<{{$x}}>{{end}}", "&lt;21>&lt;22>&lt;23>", tVal, true},
	 583  	{"declare in range", "{{range $x := .PSI}}<{{$foo:=$x}}{{$x}}>{{end}}", "&lt;21>&lt;22>&lt;23>", tVal, true},
	 584  	{"range count", `{{range $i, $x := count 5}}[{{$i}}]{{$x}}{{end}}`, "[0]a[1]b[2]c[3]d[4]e", tVal, true},
	 585  	{"range nil count", `{{range $i, $x := count 0}}{{else}}empty{{end}}`, "empty", tVal, true},
	 586  
	 587  	// Cute examples.
	 588  	{"or as if true", `{{or .SI "slice is empty"}}`, "[3 4 5]", tVal, true},
	 589  	{"or as if false", `{{or .SIEmpty "slice is empty"}}`, "slice is empty", tVal, true},
	 590  
	 591  	// Error handling.
	 592  	{"error method, error", "{{.MyError true}}", "", tVal, false},
	 593  	{"error method, no error", "{{.MyError false}}", "false", tVal, true},
	 594  
	 595  	// Numbers
	 596  	{"decimal", "{{print 1234}}", "1234", tVal, true},
	 597  	{"decimal _", "{{print 12_34}}", "1234", tVal, true},
	 598  	{"binary", "{{print 0b101}}", "5", tVal, true},
	 599  	{"binary _", "{{print 0b_1_0_1}}", "5", tVal, true},
	 600  	{"BINARY", "{{print 0B101}}", "5", tVal, true},
	 601  	{"octal0", "{{print 0377}}", "255", tVal, true},
	 602  	{"octal", "{{print 0o377}}", "255", tVal, true},
	 603  	{"octal _", "{{print 0o_3_7_7}}", "255", tVal, true},
	 604  	{"OCTAL", "{{print 0O377}}", "255", tVal, true},
	 605  	{"hex", "{{print 0x123}}", "291", tVal, true},
	 606  	{"hex _", "{{print 0x1_23}}", "291", tVal, true},
	 607  	{"HEX", "{{print 0X123ABC}}", "1194684", tVal, true},
	 608  	{"float", "{{print 123.4}}", "123.4", tVal, true},
	 609  	{"float _", "{{print 0_0_1_2_3.4}}", "123.4", tVal, true},
	 610  	{"hex float", "{{print +0x1.ep+2}}", "7.5", tVal, true},
	 611  	{"hex float _", "{{print +0x_1.e_0p+0_2}}", "7.5", tVal, true},
	 612  	{"HEX float", "{{print +0X1.EP+2}}", "7.5", tVal, true},
	 613  	{"print multi", "{{print 1_2_3_4 7.5_00_00_00}}", "1234 7.5", tVal, true},
	 614  	{"print multi2", "{{print 1234 0x0_1.e_0p+02}}", "1234 7.5", tVal, true},
	 615  
	 616  	// Fixed bugs.
	 617  	// Must separate dot and receiver; otherwise args are evaluated with dot set to variable.
	 618  	{"bug0", "{{range .MSIone}}{{if $.Method1 .}}X{{end}}{{end}}", "X", tVal, true},
	 619  	// Do not loop endlessly in indirect for non-empty interfaces.
	 620  	// The bug appears with *interface only; looped forever.
	 621  	{"bug1", "{{.Method0}}", "M0", &iVal, true},
	 622  	// Was taking address of interface field, so method set was empty.
	 623  	{"bug2", "{{$.NonEmptyInterface.Method0}}", "M0", tVal, true},
	 624  	// Struct values were not legal in with - mere oversight.
	 625  	{"bug3", "{{with $}}{{.Method0}}{{end}}", "M0", tVal, true},
	 626  	// Nil interface values in if.
	 627  	{"bug4", "{{if .Empty0}}non-nil{{else}}nil{{end}}", "nil", tVal, true},
	 628  	// Stringer.
	 629  	{"bug5", "{{.Str}}", "foozle", tVal, true},
	 630  	{"bug5a", "{{.Err}}", "erroozle", tVal, true},
	 631  	// Args need to be indirected and dereferenced sometimes.
	 632  	{"bug6a", "{{vfunc .V0 .V1}}", "vfunc", tVal, true},
	 633  	{"bug6b", "{{vfunc .V0 .V0}}", "vfunc", tVal, true},
	 634  	{"bug6c", "{{vfunc .V1 .V0}}", "vfunc", tVal, true},
	 635  	{"bug6d", "{{vfunc .V1 .V1}}", "vfunc", tVal, true},
	 636  	// Legal parse but illegal execution: non-function should have no arguments.
	 637  	{"bug7a", "{{3 2}}", "", tVal, false},
	 638  	{"bug7b", "{{$x := 1}}{{$x 2}}", "", tVal, false},
	 639  	{"bug7c", "{{$x := 1}}{{3 | $x}}", "", tVal, false},
	 640  	// Pipelined arg was not being type-checked.
	 641  	{"bug8a", "{{3|oneArg}}", "", tVal, false},
	 642  	{"bug8b", "{{4|dddArg 3}}", "", tVal, false},
	 643  	// A bug was introduced that broke map lookups for lower-case names.
	 644  	{"bug9", "{{.cause}}", "neglect", map[string]string{"cause": "neglect"}, true},
	 645  	// Field chain starting with function did not work.
	 646  	{"bug10", "{{mapOfThree.three}}-{{(mapOfThree).three}}", "3-3", 0, true},
	 647  	// Dereferencing nil pointer while evaluating function arguments should not panic. Issue 7333.
	 648  	{"bug11", "{{valueString .PS}}", "", T{}, false},
	 649  	// 0xef gave constant type float64. Issue 8622.
	 650  	{"bug12xe", "{{printf `%T` 0xef}}", "int", T{}, true},
	 651  	{"bug12xE", "{{printf `%T` 0xEE}}", "int", T{}, true},
	 652  	{"bug12Xe", "{{printf `%T` 0Xef}}", "int", T{}, true},
	 653  	{"bug12XE", "{{printf `%T` 0XEE}}", "int", T{}, true},
	 654  	// Chained nodes did not work as arguments. Issue 8473.
	 655  	{"bug13", "{{print (.Copy).I}}", "17", tVal, true},
	 656  	// Didn't protect against nil or literal values in field chains.
	 657  	{"bug14a", "{{(nil).True}}", "", tVal, false},
	 658  	{"bug14b", "{{$x := nil}}{{$x.anything}}", "", tVal, false},
	 659  	{"bug14c", `{{$x := (1.0)}}{{$y := ("hello")}}{{$x.anything}}{{$y.true}}`, "", tVal, false},
	 660  	// Didn't call validateType on function results. Issue 10800.
	 661  	{"bug15", "{{valueString returnInt}}", "", tVal, false},
	 662  	// Variadic function corner cases. Issue 10946.
	 663  	{"bug16a", "{{true|printf}}", "", tVal, false},
	 664  	{"bug16b", "{{1|printf}}", "", tVal, false},
	 665  	{"bug16c", "{{1.1|printf}}", "", tVal, false},
	 666  	{"bug16d", "{{'x'|printf}}", "", tVal, false},
	 667  	{"bug16e", "{{0i|printf}}", "", tVal, false},
	 668  	{"bug16f", "{{true|twoArgs \"xxx\"}}", "", tVal, false},
	 669  	{"bug16g", "{{\"aaa\" |twoArgs \"bbb\"}}", "twoArgs=bbbaaa", tVal, true},
	 670  	{"bug16h", "{{1|oneArg}}", "", tVal, false},
	 671  	{"bug16i", "{{\"aaa\"|oneArg}}", "oneArg=aaa", tVal, true},
	 672  	{"bug16j", "{{1+2i|printf \"%v\"}}", "(1&#43;2i)", tVal, true},
	 673  	{"bug16k", "{{\"aaa\"|printf }}", "aaa", tVal, true},
	 674  	{"bug17a", "{{.NonEmptyInterface.X}}", "x", tVal, true},
	 675  	{"bug17b", "-{{.NonEmptyInterface.Method1 1234}}-", "-1234-", tVal, true},
	 676  	{"bug17c", "{{len .NonEmptyInterfacePtS}}", "2", tVal, true},
	 677  	{"bug17d", "{{index .NonEmptyInterfacePtS 0}}", "a", tVal, true},
	 678  	{"bug17e", "{{range .NonEmptyInterfacePtS}}-{{.}}-{{end}}", "-a--b-", tVal, true},
	 679  
	 680  	// More variadic function corner cases. Some runes would get evaluated
	 681  	// as constant floats instead of ints. Issue 34483.
	 682  	{"bug18a", "{{eq . '.'}}", "true", '.', true},
	 683  	{"bug18b", "{{eq . 'e'}}", "true", 'e', true},
	 684  	{"bug18c", "{{eq . 'P'}}", "true", 'P', true},
	 685  }
	 686  
	 687  func zeroArgs() string {
	 688  	return "zeroArgs"
	 689  }
	 690  
	 691  func oneArg(a string) string {
	 692  	return "oneArg=" + a
	 693  }
	 694  
	 695  func twoArgs(a, b string) string {
	 696  	return "twoArgs=" + a + b
	 697  }
	 698  
	 699  func dddArg(a int, b ...string) string {
	 700  	return fmt.Sprintln(a, b)
	 701  }
	 702  
	 703  // count returns a channel that will deliver n sequential 1-letter strings starting at "a"
	 704  func count(n int) chan string {
	 705  	if n == 0 {
	 706  		return nil
	 707  	}
	 708  	c := make(chan string)
	 709  	go func() {
	 710  		for i := 0; i < n; i++ {
	 711  			c <- "abcdefghijklmnop"[i : i+1]
	 712  		}
	 713  		close(c)
	 714  	}()
	 715  	return c
	 716  }
	 717  
	 718  // vfunc takes a *V and a V
	 719  func vfunc(V, *V) string {
	 720  	return "vfunc"
	 721  }
	 722  
	 723  // valueString takes a string, not a pointer.
	 724  func valueString(v string) string {
	 725  	return "value is ignored"
	 726  }
	 727  
	 728  // returnInt returns an int
	 729  func returnInt() int {
	 730  	return 7
	 731  }
	 732  
	 733  func add(args ...int) int {
	 734  	sum := 0
	 735  	for _, x := range args {
	 736  		sum += x
	 737  	}
	 738  	return sum
	 739  }
	 740  
	 741  func echo(arg interface{}) interface{} {
	 742  	return arg
	 743  }
	 744  
	 745  func makemap(arg ...string) map[string]string {
	 746  	if len(arg)%2 != 0 {
	 747  		panic("bad makemap")
	 748  	}
	 749  	m := make(map[string]string)
	 750  	for i := 0; i < len(arg); i += 2 {
	 751  		m[arg[i]] = arg[i+1]
	 752  	}
	 753  	return m
	 754  }
	 755  
	 756  func stringer(s fmt.Stringer) string {
	 757  	return s.String()
	 758  }
	 759  
	 760  func mapOfThree() interface{} {
	 761  	return map[string]int{"three": 3}
	 762  }
	 763  
	 764  func testExecute(execTests []execTest, template *Template, t *testing.T) {
	 765  	b := new(bytes.Buffer)
	 766  	funcs := FuncMap{
	 767  		"add":				 add,
	 768  		"count":			 count,
	 769  		"dddArg":			dddArg,
	 770  		"echo":				echo,
	 771  		"makemap":		 makemap,
	 772  		"mapOfThree":	mapOfThree,
	 773  		"oneArg":			oneArg,
	 774  		"returnInt":	 returnInt,
	 775  		"stringer":		stringer,
	 776  		"twoArgs":		 twoArgs,
	 777  		"typeOf":			typeOf,
	 778  		"valueString": valueString,
	 779  		"vfunc":			 vfunc,
	 780  		"zeroArgs":		zeroArgs,
	 781  	}
	 782  	for _, test := range execTests {
	 783  		var tmpl *Template
	 784  		var err error
	 785  		if template == nil {
	 786  			tmpl, err = New(test.name).Funcs(funcs).Parse(test.input)
	 787  		} else {
	 788  			tmpl, err = template.Clone()
	 789  			if err != nil {
	 790  				t.Errorf("%s: clone error: %s", test.name, err)
	 791  				continue
	 792  			}
	 793  			tmpl, err = tmpl.New(test.name).Funcs(funcs).Parse(test.input)
	 794  		}
	 795  		if err != nil {
	 796  			t.Errorf("%s: parse error: %s", test.name, err)
	 797  			continue
	 798  		}
	 799  		b.Reset()
	 800  		err = tmpl.Execute(b, test.data)
	 801  		switch {
	 802  		case !test.ok && err == nil:
	 803  			t.Errorf("%s: expected error; got none", test.name)
	 804  			continue
	 805  		case test.ok && err != nil:
	 806  			t.Errorf("%s: unexpected execute error: %s", test.name, err)
	 807  			continue
	 808  		case !test.ok && err != nil:
	 809  			// expected error, got one
	 810  			if *debug {
	 811  				fmt.Printf("%s: %s\n\t%s\n", test.name, test.input, err)
	 812  			}
	 813  		}
	 814  		result := b.String()
	 815  		if result != test.output {
	 816  			t.Errorf("%s: expected\n\t%q\ngot\n\t%q", test.name, test.output, result)
	 817  		}
	 818  	}
	 819  }
	 820  
	 821  func TestExecute(t *testing.T) {
	 822  	testExecute(execTests, nil, t)
	 823  }
	 824  
	 825  var delimPairs = []string{
	 826  	"", "", // default
	 827  	"{{", "}}", // same as default
	 828  	"|", "|", // same
	 829  	"(日)", "(本)", // peculiar
	 830  }
	 831  
	 832  func TestDelims(t *testing.T) {
	 833  	const hello = "Hello, world"
	 834  	var value = struct{ Str string }{hello}
	 835  	for i := 0; i < len(delimPairs); i += 2 {
	 836  		text := ".Str"
	 837  		left := delimPairs[i+0]
	 838  		trueLeft := left
	 839  		right := delimPairs[i+1]
	 840  		trueRight := right
	 841  		if left == "" { // default case
	 842  			trueLeft = "{{"
	 843  		}
	 844  		if right == "" { // default case
	 845  			trueRight = "}}"
	 846  		}
	 847  		text = trueLeft + text + trueRight
	 848  		// Now add a comment
	 849  		text += trueLeft + "/*comment*/" + trueRight
	 850  		// Now add	an action containing a string.
	 851  		text += trueLeft + `"` + trueLeft + `"` + trueRight
	 852  		// At this point text looks like `{{.Str}}{{/*comment*/}}{{"{{"}}`.
	 853  		tmpl, err := New("delims").Delims(left, right).Parse(text)
	 854  		if err != nil {
	 855  			t.Fatalf("delim %q text %q parse err %s", left, text, err)
	 856  		}
	 857  		var b = new(bytes.Buffer)
	 858  		err = tmpl.Execute(b, value)
	 859  		if err != nil {
	 860  			t.Fatalf("delim %q exec err %s", left, err)
	 861  		}
	 862  		if b.String() != hello+trueLeft {
	 863  			t.Errorf("expected %q got %q", hello+trueLeft, b.String())
	 864  		}
	 865  	}
	 866  }
	 867  
	 868  // Check that an error from a method flows back to the top.
	 869  func TestExecuteError(t *testing.T) {
	 870  	b := new(bytes.Buffer)
	 871  	tmpl := New("error")
	 872  	_, err := tmpl.Parse("{{.MyError true}}")
	 873  	if err != nil {
	 874  		t.Fatalf("parse error: %s", err)
	 875  	}
	 876  	err = tmpl.Execute(b, tVal)
	 877  	if err == nil {
	 878  		t.Errorf("expected error; got none")
	 879  	} else if !strings.Contains(err.Error(), myError.Error()) {
	 880  		if *debug {
	 881  			fmt.Printf("test execute error: %s\n", err)
	 882  		}
	 883  		t.Errorf("expected myError; got %s", err)
	 884  	}
	 885  }
	 886  
	 887  const execErrorText = `line 1
	 888  line 2
	 889  line 3
	 890  {{template "one" .}}
	 891  {{define "one"}}{{template "two" .}}{{end}}
	 892  {{define "two"}}{{template "three" .}}{{end}}
	 893  {{define "three"}}{{index "hi" $}}{{end}}`
	 894  
	 895  // Check that an error from a nested template contains all the relevant information.
	 896  func TestExecError(t *testing.T) {
	 897  	tmpl, err := New("top").Parse(execErrorText)
	 898  	if err != nil {
	 899  		t.Fatal("parse error:", err)
	 900  	}
	 901  	var b bytes.Buffer
	 902  	err = tmpl.Execute(&b, 5) // 5 is out of range indexing "hi"
	 903  	if err == nil {
	 904  		t.Fatal("expected error")
	 905  	}
	 906  	const want = `template: top:7:20: executing "three" at <index "hi" $>: error calling index: index out of range: 5`
	 907  	got := err.Error()
	 908  	if got != want {
	 909  		t.Errorf("expected\n%q\ngot\n%q", want, got)
	 910  	}
	 911  }
	 912  
	 913  func TestJSEscaping(t *testing.T) {
	 914  	testCases := []struct {
	 915  		in, exp string
	 916  	}{
	 917  		{`a`, `a`},
	 918  		{`'foo`, `\'foo`},
	 919  		{`Go "jump" \`, `Go \"jump\" \\`},
	 920  		{`Yukihiro says "今日は世界"`, `Yukihiro says \"今日は世界\"`},
	 921  		{"unprintable \uFDFF", `unprintable \uFDFF`},
	 922  		{`<html>`, `\u003Chtml\u003E`},
	 923  		{`no = in attributes`, `no \u003D in attributes`},
	 924  		{`&#x27; does not become HTML entity`, `\u0026#x27; does not become HTML entity`},
	 925  	}
	 926  	for _, tc := range testCases {
	 927  		s := JSEscapeString(tc.in)
	 928  		if s != tc.exp {
	 929  			t.Errorf("JS escaping [%s] got [%s] want [%s]", tc.in, s, tc.exp)
	 930  		}
	 931  	}
	 932  }
	 933  
	 934  // A nice example: walk a binary tree.
	 935  
	 936  type Tree struct {
	 937  	Val				 int
	 938  	Left, Right *Tree
	 939  }
	 940  
	 941  // Use different delimiters to test Set.Delims.
	 942  // Also test the trimming of leading and trailing spaces.
	 943  const treeTemplate = `
	 944  	(- define "tree" -)
	 945  	[
	 946  		(- .Val -)
	 947  		(- with .Left -)
	 948  			(template "tree" . -)
	 949  		(- end -)
	 950  		(- with .Right -)
	 951  			(- template "tree" . -)
	 952  		(- end -)
	 953  	]
	 954  	(- end -)
	 955  `
	 956  
	 957  func TestTree(t *testing.T) {
	 958  	var tree = &Tree{
	 959  		1,
	 960  		&Tree{
	 961  			2, &Tree{
	 962  				3,
	 963  				&Tree{
	 964  					4, nil, nil,
	 965  				},
	 966  				nil,
	 967  			},
	 968  			&Tree{
	 969  				5,
	 970  				&Tree{
	 971  					6, nil, nil,
	 972  				},
	 973  				nil,
	 974  			},
	 975  		},
	 976  		&Tree{
	 977  			7,
	 978  			&Tree{
	 979  				8,
	 980  				&Tree{
	 981  					9, nil, nil,
	 982  				},
	 983  				nil,
	 984  			},
	 985  			&Tree{
	 986  				10,
	 987  				&Tree{
	 988  					11, nil, nil,
	 989  				},
	 990  				nil,
	 991  			},
	 992  		},
	 993  	}
	 994  	tmpl, err := New("root").Delims("(", ")").Parse(treeTemplate)
	 995  	if err != nil {
	 996  		t.Fatal("parse error:", err)
	 997  	}
	 998  	var b bytes.Buffer
	 999  	const expect = "[1[2[3[4]][5[6]]][7[8[9]][10[11]]]]"
	1000  	// First by looking up the template.
	1001  	err = tmpl.Lookup("tree").Execute(&b, tree)
	1002  	if err != nil {
	1003  		t.Fatal("exec error:", err)
	1004  	}
	1005  	result := b.String()
	1006  	if result != expect {
	1007  		t.Errorf("expected %q got %q", expect, result)
	1008  	}
	1009  	// Then direct to execution.
	1010  	b.Reset()
	1011  	err = tmpl.ExecuteTemplate(&b, "tree", tree)
	1012  	if err != nil {
	1013  		t.Fatal("exec error:", err)
	1014  	}
	1015  	result = b.String()
	1016  	if result != expect {
	1017  		t.Errorf("expected %q got %q", expect, result)
	1018  	}
	1019  }
	1020  
	1021  func TestExecuteOnNewTemplate(t *testing.T) {
	1022  	// This is issue 3872.
	1023  	New("Name").Templates()
	1024  	// This is issue 11379.
	1025  	// new(Template).Templates() // TODO: crashes
	1026  	// new(Template).Parse("") // TODO: crashes
	1027  	// new(Template).New("abc").Parse("") // TODO: crashes
	1028  	// new(Template).Execute(nil, nil)								// TODO: crashes; returns an error (but does not crash)
	1029  	// new(Template).ExecuteTemplate(nil, "XXX", nil) // TODO: crashes; returns an error (but does not crash)
	1030  }
	1031  
	1032  const testTemplates = `{{define "one"}}one{{end}}{{define "two"}}two{{end}}`
	1033  
	1034  func TestMessageForExecuteEmpty(t *testing.T) {
	1035  	// Test a truly empty template.
	1036  	tmpl := New("empty")
	1037  	var b bytes.Buffer
	1038  	err := tmpl.Execute(&b, 0)
	1039  	if err == nil {
	1040  		t.Fatal("expected initial error")
	1041  	}
	1042  	got := err.Error()
	1043  	want := `template: "empty" is an incomplete or empty template` // NOTE: text/template has extra "empty: " in message
	1044  	if got != want {
	1045  		t.Errorf("expected error %s got %s", want, got)
	1046  	}
	1047  
	1048  	// Add a non-empty template to check that the error is helpful.
	1049  	tmpl = New("empty")
	1050  	tests, err := New("").Parse(testTemplates)
	1051  	if err != nil {
	1052  		t.Fatal(err)
	1053  	}
	1054  	tmpl.AddParseTree("secondary", tests.Tree)
	1055  	err = tmpl.Execute(&b, 0)
	1056  	if err == nil {
	1057  		t.Fatal("expected second error")
	1058  	}
	1059  	got = err.Error()
	1060  	if got != want {
	1061  		t.Errorf("expected error %s got %s", want, got)
	1062  	}
	1063  	// Make sure we can execute the secondary.
	1064  	err = tmpl.ExecuteTemplate(&b, "secondary", 0)
	1065  	if err != nil {
	1066  		t.Fatal(err)
	1067  	}
	1068  }
	1069  
	1070  func TestFinalForPrintf(t *testing.T) {
	1071  	tmpl, err := New("").Parse(`{{"x" | printf}}`)
	1072  	if err != nil {
	1073  		t.Fatal(err)
	1074  	}
	1075  	var b bytes.Buffer
	1076  	err = tmpl.Execute(&b, 0)
	1077  	if err != nil {
	1078  		t.Fatal(err)
	1079  	}
	1080  }
	1081  
	1082  type cmpTest struct {
	1083  	expr	string
	1084  	truth string
	1085  	ok		bool
	1086  }
	1087  
	1088  var cmpTests = []cmpTest{
	1089  	{"eq true true", "true", true},
	1090  	{"eq true false", "false", true},
	1091  	{"eq 1+2i 1+2i", "true", true},
	1092  	{"eq 1+2i 1+3i", "false", true},
	1093  	{"eq 1.5 1.5", "true", true},
	1094  	{"eq 1.5 2.5", "false", true},
	1095  	{"eq 1 1", "true", true},
	1096  	{"eq 1 2", "false", true},
	1097  	{"eq `xy` `xy`", "true", true},
	1098  	{"eq `xy` `xyz`", "false", true},
	1099  	{"eq .Uthree .Uthree", "true", true},
	1100  	{"eq .Uthree .Ufour", "false", true},
	1101  	{"eq 3 4 5 6 3", "true", true},
	1102  	{"eq 3 4 5 6 7", "false", true},
	1103  	{"ne true true", "false", true},
	1104  	{"ne true false", "true", true},
	1105  	{"ne 1+2i 1+2i", "false", true},
	1106  	{"ne 1+2i 1+3i", "true", true},
	1107  	{"ne 1.5 1.5", "false", true},
	1108  	{"ne 1.5 2.5", "true", true},
	1109  	{"ne 1 1", "false", true},
	1110  	{"ne 1 2", "true", true},
	1111  	{"ne `xy` `xy`", "false", true},
	1112  	{"ne `xy` `xyz`", "true", true},
	1113  	{"ne .Uthree .Uthree", "false", true},
	1114  	{"ne .Uthree .Ufour", "true", true},
	1115  	{"lt 1.5 1.5", "false", true},
	1116  	{"lt 1.5 2.5", "true", true},
	1117  	{"lt 1 1", "false", true},
	1118  	{"lt 1 2", "true", true},
	1119  	{"lt `xy` `xy`", "false", true},
	1120  	{"lt `xy` `xyz`", "true", true},
	1121  	{"lt .Uthree .Uthree", "false", true},
	1122  	{"lt .Uthree .Ufour", "true", true},
	1123  	{"le 1.5 1.5", "true", true},
	1124  	{"le 1.5 2.5", "true", true},
	1125  	{"le 2.5 1.5", "false", true},
	1126  	{"le 1 1", "true", true},
	1127  	{"le 1 2", "true", true},
	1128  	{"le 2 1", "false", true},
	1129  	{"le `xy` `xy`", "true", true},
	1130  	{"le `xy` `xyz`", "true", true},
	1131  	{"le `xyz` `xy`", "false", true},
	1132  	{"le .Uthree .Uthree", "true", true},
	1133  	{"le .Uthree .Ufour", "true", true},
	1134  	{"le .Ufour .Uthree", "false", true},
	1135  	{"gt 1.5 1.5", "false", true},
	1136  	{"gt 1.5 2.5", "false", true},
	1137  	{"gt 1 1", "false", true},
	1138  	{"gt 2 1", "true", true},
	1139  	{"gt 1 2", "false", true},
	1140  	{"gt `xy` `xy`", "false", true},
	1141  	{"gt `xy` `xyz`", "false", true},
	1142  	{"gt .Uthree .Uthree", "false", true},
	1143  	{"gt .Uthree .Ufour", "false", true},
	1144  	{"gt .Ufour .Uthree", "true", true},
	1145  	{"ge 1.5 1.5", "true", true},
	1146  	{"ge 1.5 2.5", "false", true},
	1147  	{"ge 2.5 1.5", "true", true},
	1148  	{"ge 1 1", "true", true},
	1149  	{"ge 1 2", "false", true},
	1150  	{"ge 2 1", "true", true},
	1151  	{"ge `xy` `xy`", "true", true},
	1152  	{"ge `xy` `xyz`", "false", true},
	1153  	{"ge `xyz` `xy`", "true", true},
	1154  	{"ge .Uthree .Uthree", "true", true},
	1155  	{"ge .Uthree .Ufour", "false", true},
	1156  	{"ge .Ufour .Uthree", "true", true},
	1157  	// Mixing signed and unsigned integers.
	1158  	{"eq .Uthree .Three", "true", true},
	1159  	{"eq .Three .Uthree", "true", true},
	1160  	{"le .Uthree .Three", "true", true},
	1161  	{"le .Three .Uthree", "true", true},
	1162  	{"ge .Uthree .Three", "true", true},
	1163  	{"ge .Three .Uthree", "true", true},
	1164  	{"lt .Uthree .Three", "false", true},
	1165  	{"lt .Three .Uthree", "false", true},
	1166  	{"gt .Uthree .Three", "false", true},
	1167  	{"gt .Three .Uthree", "false", true},
	1168  	{"eq .Ufour .Three", "false", true},
	1169  	{"lt .Ufour .Three", "false", true},
	1170  	{"gt .Ufour .Three", "true", true},
	1171  	{"eq .NegOne .Uthree", "false", true},
	1172  	{"eq .Uthree .NegOne", "false", true},
	1173  	{"ne .NegOne .Uthree", "true", true},
	1174  	{"ne .Uthree .NegOne", "true", true},
	1175  	{"lt .NegOne .Uthree", "true", true},
	1176  	{"lt .Uthree .NegOne", "false", true},
	1177  	{"le .NegOne .Uthree", "true", true},
	1178  	{"le .Uthree .NegOne", "false", true},
	1179  	{"gt .NegOne .Uthree", "false", true},
	1180  	{"gt .Uthree .NegOne", "true", true},
	1181  	{"ge .NegOne .Uthree", "false", true},
	1182  	{"ge .Uthree .NegOne", "true", true},
	1183  	{"eq (index `x` 0) 'x'", "true", true}, // The example that triggered this rule.
	1184  	{"eq (index `x` 0) 'y'", "false", true},
	1185  	{"eq .V1 .V2", "true", true},
	1186  	{"eq .Ptr .Ptr", "true", true},
	1187  	{"eq .Ptr .NilPtr", "false", true},
	1188  	{"eq .NilPtr .NilPtr", "true", true},
	1189  	{"eq .Iface1 .Iface1", "true", true},
	1190  	{"eq .Iface1 .Iface2", "false", true},
	1191  	{"eq .Iface2 .Iface2", "true", true},
	1192  	// Errors
	1193  	{"eq `xy` 1", "", false},			 // Different types.
	1194  	{"eq 2 2.0", "", false},				// Different types.
	1195  	{"lt true true", "", false},		// Unordered types.
	1196  	{"lt 1+0i 1+0i", "", false},		// Unordered types.
	1197  	{"eq .Ptr 1", "", false},			 // Incompatible types.
	1198  	{"eq .Ptr .NegOne", "", false}, // Incompatible types.
	1199  	{"eq .Map .Map", "", false},		// Uncomparable types.
	1200  	{"eq .Map .V1", "", false},		 // Uncomparable types.
	1201  }
	1202  
	1203  func TestComparison(t *testing.T) {
	1204  	b := new(bytes.Buffer)
	1205  	var cmpStruct = struct {
	1206  		Uthree, Ufour	uint
	1207  		NegOne, Three	int
	1208  		Ptr, NilPtr		*int
	1209  		Map						map[int]int
	1210  		V1, V2				 V
	1211  		Iface1, Iface2 fmt.Stringer
	1212  	}{
	1213  		Uthree: 3,
	1214  		Ufour:	4,
	1215  		NegOne: -1,
	1216  		Three:	3,
	1217  		Ptr:		new(int),
	1218  		Iface1: b,
	1219  	}
	1220  	for _, test := range cmpTests {
	1221  		text := fmt.Sprintf("{{if %s}}true{{else}}false{{end}}", test.expr)
	1222  		tmpl, err := New("empty").Parse(text)
	1223  		if err != nil {
	1224  			t.Fatalf("%q: %s", test.expr, err)
	1225  		}
	1226  		b.Reset()
	1227  		err = tmpl.Execute(b, &cmpStruct)
	1228  		if test.ok && err != nil {
	1229  			t.Errorf("%s errored incorrectly: %s", test.expr, err)
	1230  			continue
	1231  		}
	1232  		if !test.ok && err == nil {
	1233  			t.Errorf("%s did not error", test.expr)
	1234  			continue
	1235  		}
	1236  		if b.String() != test.truth {
	1237  			t.Errorf("%s: want %s; got %s", test.expr, test.truth, b.String())
	1238  		}
	1239  	}
	1240  }
	1241  
	1242  func TestMissingMapKey(t *testing.T) {
	1243  	data := map[string]int{
	1244  		"x": 99,
	1245  	}
	1246  	tmpl, err := New("t1").Parse("{{.x}} {{.y}}")
	1247  	if err != nil {
	1248  		t.Fatal(err)
	1249  	}
	1250  	var b bytes.Buffer
	1251  	// By default, just get "<no value>" // NOTE: not in html/template, get empty string
	1252  	err = tmpl.Execute(&b, data)
	1253  	if err != nil {
	1254  		t.Fatal(err)
	1255  	}
	1256  	want := "99 "
	1257  	got := b.String()
	1258  	if got != want {
	1259  		t.Errorf("got %q; expected %q", got, want)
	1260  	}
	1261  	// Same if we set the option explicitly to the default.
	1262  	tmpl.Option("missingkey=default")
	1263  	b.Reset()
	1264  	err = tmpl.Execute(&b, data)
	1265  	if err != nil {
	1266  		t.Fatal("default:", err)
	1267  	}
	1268  	got = b.String()
	1269  	if got != want {
	1270  		t.Errorf("got %q; expected %q", got, want)
	1271  	}
	1272  	// Next we ask for a zero value
	1273  	tmpl.Option("missingkey=zero")
	1274  	b.Reset()
	1275  	err = tmpl.Execute(&b, data)
	1276  	if err != nil {
	1277  		t.Fatal("zero:", err)
	1278  	}
	1279  	want = "99 0"
	1280  	got = b.String()
	1281  	if got != want {
	1282  		t.Errorf("got %q; expected %q", got, want)
	1283  	}
	1284  	// Now we ask for an error.
	1285  	tmpl.Option("missingkey=error")
	1286  	err = tmpl.Execute(&b, data)
	1287  	if err == nil {
	1288  		t.Errorf("expected error; got none")
	1289  	}
	1290  	// same Option, but now a nil interface: ask for an error
	1291  	err = tmpl.Execute(&b, nil)
	1292  	t.Log(err)
	1293  	if err == nil {
	1294  		t.Errorf("expected error for nil-interface; got none")
	1295  	}
	1296  }
	1297  
	1298  // Test that the error message for multiline unterminated string
	1299  // refers to the line number of the opening quote.
	1300  func TestUnterminatedStringError(t *testing.T) {
	1301  	_, err := New("X").Parse("hello\n\n{{`unterminated\n\n\n\n}}\n some more\n\n")
	1302  	if err == nil {
	1303  		t.Fatal("expected error")
	1304  	}
	1305  	str := err.Error()
	1306  	if !strings.Contains(str, "X:3: unterminated raw quoted string") {
	1307  		t.Fatalf("unexpected error: %s", str)
	1308  	}
	1309  }
	1310  
	1311  const alwaysErrorText = "always be failing"
	1312  
	1313  var alwaysError = errors.New(alwaysErrorText)
	1314  
	1315  type ErrorWriter int
	1316  
	1317  func (e ErrorWriter) Write(p []byte) (int, error) {
	1318  	return 0, alwaysError
	1319  }
	1320  
	1321  func TestExecuteGivesExecError(t *testing.T) {
	1322  	// First, a non-execution error shouldn't be an ExecError.
	1323  	tmpl, err := New("X").Parse("hello")
	1324  	if err != nil {
	1325  		t.Fatal(err)
	1326  	}
	1327  	err = tmpl.Execute(ErrorWriter(0), 0)
	1328  	if err == nil {
	1329  		t.Fatal("expected error; got none")
	1330  	}
	1331  	if err.Error() != alwaysErrorText {
	1332  		t.Errorf("expected %q error; got %q", alwaysErrorText, err)
	1333  	}
	1334  	// This one should be an ExecError.
	1335  	tmpl, err = New("X").Parse("hello, {{.X.Y}}")
	1336  	if err != nil {
	1337  		t.Fatal(err)
	1338  	}
	1339  	err = tmpl.Execute(io.Discard, 0)
	1340  	if err == nil {
	1341  		t.Fatal("expected error; got none")
	1342  	}
	1343  	eerr, ok := err.(template.ExecError)
	1344  	if !ok {
	1345  		t.Fatalf("did not expect ExecError %s", eerr)
	1346  	}
	1347  	expect := "field X in type int"
	1348  	if !strings.Contains(err.Error(), expect) {
	1349  		t.Errorf("expected %q; got %q", expect, err)
	1350  	}
	1351  }
	1352  
	1353  func funcNameTestFunc() int {
	1354  	return 0
	1355  }
	1356  
	1357  func TestGoodFuncNames(t *testing.T) {
	1358  	names := []string{
	1359  		"_",
	1360  		"a",
	1361  		"a1",
	1362  		"a1",
	1363  		"Ӵ",
	1364  	}
	1365  	for _, name := range names {
	1366  		tmpl := New("X").Funcs(
	1367  			FuncMap{
	1368  				name: funcNameTestFunc,
	1369  			},
	1370  		)
	1371  		if tmpl == nil {
	1372  			t.Fatalf("nil result for %q", name)
	1373  		}
	1374  	}
	1375  }
	1376  
	1377  func TestBadFuncNames(t *testing.T) {
	1378  	names := []string{
	1379  		"",
	1380  		"2",
	1381  		"a-b",
	1382  	}
	1383  	for _, name := range names {
	1384  		testBadFuncName(name, t)
	1385  	}
	1386  }
	1387  
	1388  func testBadFuncName(name string, t *testing.T) {
	1389  	t.Helper()
	1390  	defer func() {
	1391  		recover()
	1392  	}()
	1393  	New("X").Funcs(
	1394  		FuncMap{
	1395  			name: funcNameTestFunc,
	1396  		},
	1397  	)
	1398  	// If we get here, the name did not cause a panic, which is how Funcs
	1399  	// reports an error.
	1400  	t.Errorf("%q succeeded incorrectly as function name", name)
	1401  }
	1402  
	1403  func TestBlock(t *testing.T) {
	1404  	const (
	1405  		input	 = `a({{block "inner" .}}bar({{.}})baz{{end}})b`
	1406  		want		= `a(bar(hello)baz)b`
	1407  		overlay = `{{define "inner"}}foo({{.}})bar{{end}}`
	1408  		want2	 = `a(foo(goodbye)bar)b`
	1409  	)
	1410  	tmpl, err := New("outer").Parse(input)
	1411  	if err != nil {
	1412  		t.Fatal(err)
	1413  	}
	1414  	tmpl2, err := Must(tmpl.Clone()).Parse(overlay)
	1415  	if err != nil {
	1416  		t.Fatal(err)
	1417  	}
	1418  
	1419  	var buf bytes.Buffer
	1420  	if err := tmpl.Execute(&buf, "hello"); err != nil {
	1421  		t.Fatal(err)
	1422  	}
	1423  	if got := buf.String(); got != want {
	1424  		t.Errorf("got %q, want %q", got, want)
	1425  	}
	1426  
	1427  	buf.Reset()
	1428  	if err := tmpl2.Execute(&buf, "goodbye"); err != nil {
	1429  		t.Fatal(err)
	1430  	}
	1431  	if got := buf.String(); got != want2 {
	1432  		t.Errorf("got %q, want %q", got, want2)
	1433  	}
	1434  }
	1435  
	1436  func TestEvalFieldErrors(t *testing.T) {
	1437  	tests := []struct {
	1438  		name, src string
	1439  		value		 interface{}
	1440  		want			string
	1441  	}{
	1442  		{
	1443  			// Check that calling an invalid field on nil pointer
	1444  			// prints a field error instead of a distracting nil
	1445  			// pointer error. https://golang.org/issue/15125
	1446  			"MissingFieldOnNil",
	1447  			"{{.MissingField}}",
	1448  			(*T)(nil),
	1449  			"can't evaluate field MissingField in type *template.T",
	1450  		},
	1451  		{
	1452  			"MissingFieldOnNonNil",
	1453  			"{{.MissingField}}",
	1454  			&T{},
	1455  			"can't evaluate field MissingField in type *template.T",
	1456  		},
	1457  		{
	1458  			"ExistingFieldOnNil",
	1459  			"{{.X}}",
	1460  			(*T)(nil),
	1461  			"nil pointer evaluating *template.T.X",
	1462  		},
	1463  		{
	1464  			"MissingKeyOnNilMap",
	1465  			"{{.MissingKey}}",
	1466  			(*map[string]string)(nil),
	1467  			"nil pointer evaluating *map[string]string.MissingKey",
	1468  		},
	1469  		{
	1470  			"MissingKeyOnNilMapPtr",
	1471  			"{{.MissingKey}}",
	1472  			(*map[string]string)(nil),
	1473  			"nil pointer evaluating *map[string]string.MissingKey",
	1474  		},
	1475  		{
	1476  			"MissingKeyOnMapPtrToNil",
	1477  			"{{.MissingKey}}",
	1478  			&map[string]string{},
	1479  			"<nil>",
	1480  		},
	1481  	}
	1482  	for _, tc := range tests {
	1483  		t.Run(tc.name, func(t *testing.T) {
	1484  			tmpl := Must(New("tmpl").Parse(tc.src))
	1485  			err := tmpl.Execute(io.Discard, tc.value)
	1486  			got := "<nil>"
	1487  			if err != nil {
	1488  				got = err.Error()
	1489  			}
	1490  			if !strings.HasSuffix(got, tc.want) {
	1491  				t.Fatalf("got error %q, want %q", got, tc.want)
	1492  			}
	1493  		})
	1494  	}
	1495  }
	1496  
	1497  func TestMaxExecDepth(t *testing.T) {
	1498  	if testing.Short() {
	1499  		t.Skip("skipping in -short mode")
	1500  	}
	1501  	tmpl := Must(New("tmpl").Parse(`{{template "tmpl" .}}`))
	1502  	err := tmpl.Execute(io.Discard, nil)
	1503  	got := "<nil>"
	1504  	if err != nil {
	1505  		got = err.Error()
	1506  	}
	1507  	const want = "exceeded maximum template depth"
	1508  	if !strings.Contains(got, want) {
	1509  		t.Errorf("got error %q; want %q", got, want)
	1510  	}
	1511  }
	1512  
	1513  func TestAddrOfIndex(t *testing.T) {
	1514  	// golang.org/issue/14916.
	1515  	// Before index worked on reflect.Values, the .String could not be
	1516  	// found on the (incorrectly unaddressable) V value,
	1517  	// in contrast to range, which worked fine.
	1518  	// Also testing that passing a reflect.Value to tmpl.Execute works.
	1519  	texts := []string{
	1520  		`{{range .}}{{.String}}{{end}}`,
	1521  		`{{with index . 0}}{{.String}}{{end}}`,
	1522  	}
	1523  	for _, text := range texts {
	1524  		tmpl := Must(New("tmpl").Parse(text))
	1525  		var buf bytes.Buffer
	1526  		err := tmpl.Execute(&buf, reflect.ValueOf([]V{{1}}))
	1527  		if err != nil {
	1528  			t.Fatalf("%s: Execute: %v", text, err)
	1529  		}
	1530  		if buf.String() != "&lt;1&gt;" {
	1531  			t.Fatalf("%s: template output = %q, want %q", text, &buf, "&lt;1&gt;")
	1532  		}
	1533  	}
	1534  }
	1535  
	1536  func TestInterfaceValues(t *testing.T) {
	1537  	// golang.org/issue/17714.
	1538  	// Before index worked on reflect.Values, interface values
	1539  	// were always implicitly promoted to the underlying value,
	1540  	// except that nil interfaces were promoted to the zero reflect.Value.
	1541  	// Eliminating a round trip to interface{} and back to reflect.Value
	1542  	// eliminated this promotion, breaking these cases.
	1543  	tests := []struct {
	1544  		text string
	1545  		out	string
	1546  	}{
	1547  		{`{{index .Nil 1}}`, "ERROR: index of untyped nil"},
	1548  		{`{{index .Slice 2}}`, "2"},
	1549  		{`{{index .Slice .Two}}`, "2"},
	1550  		{`{{call .Nil 1}}`, "ERROR: call of nil"},
	1551  		{`{{call .PlusOne 1}}`, "2"},
	1552  		{`{{call .PlusOne .One}}`, "2"},
	1553  		{`{{and (index .Slice 0) true}}`, "0"},
	1554  		{`{{and .Zero true}}`, "0"},
	1555  		{`{{and (index .Slice 1) false}}`, "false"},
	1556  		{`{{and .One false}}`, "false"},
	1557  		{`{{or (index .Slice 0) false}}`, "false"},
	1558  		{`{{or .Zero false}}`, "false"},
	1559  		{`{{or (index .Slice 1) true}}`, "1"},
	1560  		{`{{or .One true}}`, "1"},
	1561  		{`{{not (index .Slice 0)}}`, "true"},
	1562  		{`{{not .Zero}}`, "true"},
	1563  		{`{{not (index .Slice 1)}}`, "false"},
	1564  		{`{{not .One}}`, "false"},
	1565  		{`{{eq (index .Slice 0) .Zero}}`, "true"},
	1566  		{`{{eq (index .Slice 1) .One}}`, "true"},
	1567  		{`{{ne (index .Slice 0) .Zero}}`, "false"},
	1568  		{`{{ne (index .Slice 1) .One}}`, "false"},
	1569  		{`{{ge (index .Slice 0) .One}}`, "false"},
	1570  		{`{{ge (index .Slice 1) .Zero}}`, "true"},
	1571  		{`{{gt (index .Slice 0) .One}}`, "false"},
	1572  		{`{{gt (index .Slice 1) .Zero}}`, "true"},
	1573  		{`{{le (index .Slice 0) .One}}`, "true"},
	1574  		{`{{le (index .Slice 1) .Zero}}`, "false"},
	1575  		{`{{lt (index .Slice 0) .One}}`, "true"},
	1576  		{`{{lt (index .Slice 1) .Zero}}`, "false"},
	1577  	}
	1578  
	1579  	for _, tt := range tests {
	1580  		tmpl := Must(New("tmpl").Parse(tt.text))
	1581  		var buf bytes.Buffer
	1582  		err := tmpl.Execute(&buf, map[string]interface{}{
	1583  			"PlusOne": func(n int) int {
	1584  				return n + 1
	1585  			},
	1586  			"Slice": []int{0, 1, 2, 3},
	1587  			"One":	 1,
	1588  			"Two":	 2,
	1589  			"Nil":	 nil,
	1590  			"Zero":	0,
	1591  		})
	1592  		if strings.HasPrefix(tt.out, "ERROR:") {
	1593  			e := strings.TrimSpace(strings.TrimPrefix(tt.out, "ERROR:"))
	1594  			if err == nil || !strings.Contains(err.Error(), e) {
	1595  				t.Errorf("%s: Execute: %v, want error %q", tt.text, err, e)
	1596  			}
	1597  			continue
	1598  		}
	1599  		if err != nil {
	1600  			t.Errorf("%s: Execute: %v", tt.text, err)
	1601  			continue
	1602  		}
	1603  		if buf.String() != tt.out {
	1604  			t.Errorf("%s: template output = %q, want %q", tt.text, &buf, tt.out)
	1605  		}
	1606  	}
	1607  }
	1608  
	1609  // Check that panics during calls are recovered and returned as errors.
	1610  func TestExecutePanicDuringCall(t *testing.T) {
	1611  	funcs := map[string]interface{}{
	1612  		"doPanic": func() string {
	1613  			panic("custom panic string")
	1614  		},
	1615  	}
	1616  	tests := []struct {
	1617  		name		string
	1618  		input	 string
	1619  		data		interface{}
	1620  		wantErr string
	1621  	}{
	1622  		{
	1623  			"direct func call panics",
	1624  			"{{doPanic}}", (*T)(nil),
	1625  			`template: t:1:2: executing "t" at <doPanic>: error calling doPanic: custom panic string`,
	1626  		},
	1627  		{
	1628  			"indirect func call panics",
	1629  			"{{call doPanic}}", (*T)(nil),
	1630  			`template: t:1:7: executing "t" at <doPanic>: error calling doPanic: custom panic string`,
	1631  		},
	1632  		{
	1633  			"direct method call panics",
	1634  			"{{.GetU}}", (*T)(nil),
	1635  			`template: t:1:2: executing "t" at <.GetU>: error calling GetU: runtime error: invalid memory address or nil pointer dereference`,
	1636  		},
	1637  		{
	1638  			"indirect method call panics",
	1639  			"{{call .GetU}}", (*T)(nil),
	1640  			`template: t:1:7: executing "t" at <.GetU>: error calling GetU: runtime error: invalid memory address or nil pointer dereference`,
	1641  		},
	1642  		{
	1643  			"func field call panics",
	1644  			"{{call .PanicFunc}}", tVal,
	1645  			`template: t:1:2: executing "t" at <call .PanicFunc>: error calling call: test panic`,
	1646  		},
	1647  		{
	1648  			"method call on nil interface",
	1649  			"{{.NonEmptyInterfaceNil.Method0}}", tVal,
	1650  			`template: t:1:23: executing "t" at <.NonEmptyInterfaceNil.Method0>: nil pointer evaluating template.I.Method0`,
	1651  		},
	1652  	}
	1653  	for _, tc := range tests {
	1654  		b := new(bytes.Buffer)
	1655  		tmpl, err := New("t").Funcs(funcs).Parse(tc.input)
	1656  		if err != nil {
	1657  			t.Fatalf("parse error: %s", err)
	1658  		}
	1659  		err = tmpl.Execute(b, tc.data)
	1660  		if err == nil {
	1661  			t.Errorf("%s: expected error; got none", tc.name)
	1662  		} else if !strings.Contains(err.Error(), tc.wantErr) {
	1663  			if *debug {
	1664  				fmt.Printf("%s: test execute error: %s\n", tc.name, err)
	1665  			}
	1666  			t.Errorf("%s: expected error:\n%s\ngot:\n%s", tc.name, tc.wantErr, err)
	1667  		}
	1668  	}
	1669  }
	1670  
	1671  // Issue 31810. Check that a parenthesized first argument behaves properly.
	1672  func TestIssue31810(t *testing.T) {
	1673  	t.Skip("broken in html/template")
	1674  
	1675  	// A simple value with no arguments is fine.
	1676  	var b bytes.Buffer
	1677  	const text = "{{ (.)	}}"
	1678  	tmpl, err := New("").Parse(text)
	1679  	if err != nil {
	1680  		t.Error(err)
	1681  	}
	1682  	err = tmpl.Execute(&b, "result")
	1683  	if err != nil {
	1684  		t.Error(err)
	1685  	}
	1686  	if b.String() != "result" {
	1687  		t.Errorf("%s got %q, expected %q", text, b.String(), "result")
	1688  	}
	1689  
	1690  	// Even a plain function fails - need to use call.
	1691  	f := func() string { return "result" }
	1692  	b.Reset()
	1693  	err = tmpl.Execute(&b, f)
	1694  	if err == nil {
	1695  		t.Error("expected error with no call, got none")
	1696  	}
	1697  
	1698  	// Works if the function is explicitly called.
	1699  	const textCall = "{{ (call .)	}}"
	1700  	tmpl, err = New("").Parse(textCall)
	1701  	b.Reset()
	1702  	err = tmpl.Execute(&b, f)
	1703  	if err != nil {
	1704  		t.Error(err)
	1705  	}
	1706  	if b.String() != "result" {
	1707  		t.Errorf("%s got %q, expected %q", textCall, b.String(), "result")
	1708  	}
	1709  }
	1710  
	1711  // Issue 39807. There was a race applying escapeTemplate.
	1712  
	1713  const raceText = `
	1714  {{- define "jstempl" -}}
	1715  var v = "v";
	1716  {{- end -}}
	1717  <script type="application/javascript">
	1718  {{ template "jstempl" $ }}
	1719  </script>
	1720  `
	1721  
	1722  func TestEscapeRace(t *testing.T) {
	1723  	tmpl := New("")
	1724  	_, err := tmpl.New("templ.html").Parse(raceText)
	1725  	if err != nil {
	1726  		t.Fatal(err)
	1727  	}
	1728  	const count = 20
	1729  	for i := 0; i < count; i++ {
	1730  		_, err := tmpl.New(fmt.Sprintf("x%d.html", i)).Parse(`{{ template "templ.html" .}}`)
	1731  		if err != nil {
	1732  			t.Fatal(err)
	1733  		}
	1734  	}
	1735  
	1736  	var wg sync.WaitGroup
	1737  	for i := 0; i < 10; i++ {
	1738  		wg.Add(1)
	1739  		go func() {
	1740  			defer wg.Done()
	1741  			for j := 0; j < count; j++ {
	1742  				sub := tmpl.Lookup(fmt.Sprintf("x%d.html", j))
	1743  				if err := sub.Execute(io.Discard, nil); err != nil {
	1744  					t.Error(err)
	1745  				}
	1746  			}
	1747  		}()
	1748  	}
	1749  	wg.Wait()
	1750  }
	1751  
	1752  func TestRecursiveExecute(t *testing.T) {
	1753  	tmpl := New("")
	1754  
	1755  	recur := func() (HTML, error) {
	1756  		var sb strings.Builder
	1757  		if err := tmpl.ExecuteTemplate(&sb, "subroutine", nil); err != nil {
	1758  			t.Fatal(err)
	1759  		}
	1760  		return HTML(sb.String()), nil
	1761  	}
	1762  
	1763  	m := FuncMap{
	1764  		"recur": recur,
	1765  	}
	1766  
	1767  	top, err := tmpl.New("x.html").Funcs(m).Parse(`{{recur}}`)
	1768  	if err != nil {
	1769  		t.Fatal(err)
	1770  	}
	1771  	_, err = tmpl.New("subroutine").Parse(`<a href="/x?p={{"'a<b'"}}">`)
	1772  	if err != nil {
	1773  		t.Fatal(err)
	1774  	}
	1775  	if err := top.Execute(io.Discard, nil); err != nil {
	1776  		t.Fatal(err)
	1777  	}
	1778  }
	1779  
	1780  // recursiveInvoker is for TestRecursiveExecuteViaMethod.
	1781  type recursiveInvoker struct {
	1782  	t		*testing.T
	1783  	tmpl *Template
	1784  }
	1785  
	1786  func (r *recursiveInvoker) Recur() (string, error) {
	1787  	var sb strings.Builder
	1788  	if err := r.tmpl.ExecuteTemplate(&sb, "subroutine", nil); err != nil {
	1789  		r.t.Fatal(err)
	1790  	}
	1791  	return sb.String(), nil
	1792  }
	1793  
	1794  func TestRecursiveExecuteViaMethod(t *testing.T) {
	1795  	tmpl := New("")
	1796  	top, err := tmpl.New("x.html").Parse(`{{.Recur}}`)
	1797  	if err != nil {
	1798  		t.Fatal(err)
	1799  	}
	1800  	_, err = tmpl.New("subroutine").Parse(`<a href="/x?p={{"'a<b'"}}">`)
	1801  	if err != nil {
	1802  		t.Fatal(err)
	1803  	}
	1804  	r := &recursiveInvoker{
	1805  		t:		t,
	1806  		tmpl: tmpl,
	1807  	}
	1808  	if err := top.Execute(io.Discard, r); err != nil {
	1809  		t.Fatal(err)
	1810  	}
	1811  }
	1812  
	1813  // Issue 43295.
	1814  func TestTemplateFuncsAfterClone(t *testing.T) {
	1815  	s := `{{ f . }}`
	1816  	want := "test"
	1817  	orig := New("orig").Funcs(map[string]interface{}{
	1818  		"f": func(in string) string {
	1819  			return in
	1820  		},
	1821  	}).New("child")
	1822  
	1823  	overviewTmpl := Must(Must(orig.Clone()).Parse(s))
	1824  	var out strings.Builder
	1825  	if err := overviewTmpl.Execute(&out, want); err != nil {
	1826  		t.Fatal(err)
	1827  	}
	1828  	if got := out.String(); got != want {
	1829  		t.Fatalf("got %q; want %q", got, want)
	1830  	}
	1831  }
	1832  

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