src/pkg/text/template/parse/parse_test.go - go - 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 parse

 import (
 	"flag"
 	"fmt"
 	"strings"
 	"testing"
 )

 var debug = flag.Bool("debug", false, "show the errors produced by the main tests")

 type numberTest struct {
 	text      string
 	isInt     bool
 	isUint    bool
 	isFloat   bool
 	isComplex bool
 	int64
 	uint64
 	float64
 	complex128
 }

 var numberTests = []numberTest{
 	// basics
 	{"0", true, true, true, false, 0, 0, 0, 0},
 	{"-0", true, true, true, false, 0, 0, 0, 0}, // check that -0 is a uint.
 	{"73", true, true, true, false, 73, 73, 73, 0},
 	{"073", true, true, true, false, 073, 073, 073, 0},
 	{"0x73", true, true, true, false, 0x73, 0x73, 0x73, 0},
 	{"-73", true, false, true, false, -73, 0, -73, 0},
 	{"+73", true, false, true, false, 73, 0, 73, 0},
 	{"100", true, true, true, false, 100, 100, 100, 0},
 	{"1e9", true, true, true, false, 1e9, 1e9, 1e9, 0},
 	{"-1e9", true, false, true, false, -1e9, 0, -1e9, 0},
 	{"-1.2", false, false, true, false, 0, 0, -1.2, 0},
 	{"1e19", false, true, true, false, 0, 1e19, 1e19, 0},
 	{"-1e19", false, false, true, false, 0, 0, -1e19, 0},
 	{"4i", false, false, false, true, 0, 0, 0, 4i},
 	{"-1.2+4.2i", false, false, false, true, 0, 0, 0, -1.2 + 4.2i},
 	{"073i", false, false, false, true, 0, 0, 0, 73i}, // not octal!
 	// complex with 0 imaginary are float (and maybe integer)
 	{"0i", true, true, true, true, 0, 0, 0, 0},
 	{"-1.2+0i", false, false, true, true, 0, 0, -1.2, -1.2},
 	{"-12+0i", true, false, true, true, -12, 0, -12, -12},
 	{"13+0i", true, true, true, true, 13, 13, 13, 13},
 	// funny bases
 	{"0123", true, true, true, false, 0123, 0123, 0123, 0},
 	{"-0x0", true, true, true, false, 0, 0, 0, 0},
 	{"0xdeadbeef", true, true, true, false, 0xdeadbeef, 0xdeadbeef, 0xdeadbeef, 0},
 	// character constants
 	{`'a'`, true, true, true, false, 'a', 'a', 'a', 0},
 	{`'\n'`, true, true, true, false, '\n', '\n', '\n', 0},
 	{`'\\'`, true, true, true, false, '\\', '\\', '\\', 0},
 	{`'\''`, true, true, true, false, '\'', '\'', '\'', 0},
 	{`'\xFF'`, true, true, true, false, 0xFF, 0xFF, 0xFF, 0},
 	{`'パ'`, true, true, true, false, 0x30d1, 0x30d1, 0x30d1, 0},
 	{`'\u30d1'`, true, true, true, false, 0x30d1, 0x30d1, 0x30d1, 0},
 	{`'\U000030d1'`, true, true, true, false, 0x30d1, 0x30d1, 0x30d1, 0},
 	// some broken syntax
 	{text: "+-2"},
 	{text: "0x123."},
 	{text: "1e."},
 	{text: "0xi."},
 	{text: "1+2."},
 	{text: "'x"},
 	{text: "'xx'"},
 }

 func TestNumberParse(t *testing.T) {
 	for _, test := range numberTests {
 		// If fmt.Sscan thinks it's complex, it's complex.  We can't trust the output
 		// because imaginary comes out as a number.
 		var c complex128
 		typ := itemNumber
 		if test.text[0] == '\'' {
 			typ = itemCharConstant
 		} else {
 			_, err := fmt.Sscan(test.text, &c)
 			if err == nil {
 				typ = itemComplex
 			}
 		}
 		n, err := newNumber(0, test.text, typ)
 		ok := test.isInt || test.isUint || test.isFloat || test.isComplex
 		if ok && err != nil {
 			t.Errorf("unexpected error for %q: %s", test.text, err)
 			continue
 		}
 		if !ok && err == nil {
 			t.Errorf("expected error for %q", test.text)
 			continue
 		}
 		if !ok {
 			if *debug {
 				fmt.Printf("%s\n\t%s\n", test.text, err)
 			}
 			continue
 		}
 		if n.IsComplex != test.isComplex {
 			t.Errorf("complex incorrect for %q; should be %t", test.text, test.isComplex)
 		}
 		if test.isInt {
 			if !n.IsInt {
 				t.Errorf("expected integer for %q", test.text)
 			}
 			if n.Int64 != test.int64 {
 				t.Errorf("int64 for %q should be %d Is %d", test.text, test.int64, n.Int64)
 			}
 		} else if n.IsInt {
 			t.Errorf("did not expect integer for %q", test.text)
 		}
 		if test.isUint {
 			if !n.IsUint {
 				t.Errorf("expected unsigned integer for %q", test.text)
 			}
 			if n.Uint64 != test.uint64 {
 				t.Errorf("uint64 for %q should be %d Is %d", test.text, test.uint64, n.Uint64)
 			}
 		} else if n.IsUint {
 			t.Errorf("did not expect unsigned integer for %q", test.text)
 		}
 		if test.isFloat {
 			if !n.IsFloat {
 				t.Errorf("expected float for %q", test.text)
 			}
 			if n.Float64 != test.float64 {
 				t.Errorf("float64 for %q should be %g Is %g", test.text, test.float64, n.Float64)
 			}
 		} else if n.IsFloat {
 			t.Errorf("did not expect float for %q", test.text)
 		}
 		if test.isComplex {
 			if !n.IsComplex {
 				t.Errorf("expected complex for %q", test.text)
 			}
 			if n.Complex128 != test.complex128 {
 				t.Errorf("complex128 for %q should be %g Is %g", test.text, test.complex128, n.Complex128)
 			}
 		} else if n.IsComplex {
 			t.Errorf("did not expect complex for %q", test.text)
 		}
 	}
 }

 type parseTest struct {
 	name   string
 	input  string
 	ok     bool
 	result string // what the user would see in an error message.
 }

 const (
 	noError  = true
 	hasError = false
 )

 var parseTests = []parseTest{
 	{"empty", "", noError,
 		``},
 	{"comment", "{{/*\n\n\n*/}}", noError,
 		``},
 	{"spaces", " \t\n", noError,
 		`" \t\n"`},
 	{"text", "some text", noError,
 		`"some text"`},
 	{"emptyAction", "{{}}", hasError,
 		`{{}}`},
 	{"field", "{{.X}}", noError,
 		`{{.X}}`},
 	{"simple command", "{{printf}}", noError,
 		`{{printf}}`},
 	{"$ invocation", "{{$}}", noError,
 		"{{$}}"},
 	{"variable invocation", "{{with $x := 3}}{{$x 23}}{{end}}", noError,
 		"{{with $x := 3}}{{$x 23}}{{end}}"},
 	{"variable with fields", "{{$.I}}", noError,
 		"{{$.I}}"},
 	{"multi-word command", "{{printf `%d` 23}}", noError,
 		"{{printf `%d` 23}}"},
 	{"pipeline", "{{.X|.Y}}", noError,
 		`{{.X | .Y}}`},
 	{"pipeline with decl", "{{$x := .X|.Y}}", noError,
 		`{{$x := .X | .Y}}`},
 	{"nested pipeline", "{{.X (.Y .Z) (.A | .B .C) (.E)}}", noError,
 		`{{.X (.Y .Z) (.A | .B .C) (.E)}}`},
 	{"field applied to parentheses", "{{(.Y .Z).Field}}", noError,
 		`{{(.Y .Z).Field}}`},
 	{"simple if", "{{if .X}}hello{{end}}", noError,
 		`{{if .X}}"hello"{{end}}`},
 	{"if with else", "{{if .X}}true{{else}}false{{end}}", noError,
 		`{{if .X}}"true"{{else}}"false"{{end}}`},
 	{"if with else if", "{{if .X}}true{{else if .Y}}false{{end}}", noError,
 		`{{if .X}}"true"{{else}}{{if .Y}}"false"{{end}}{{end}}`},
 	{"if else chain", "+{{if .X}}X{{else if .Y}}Y{{else if .Z}}Z{{end}}+", noError,
 		`"+"{{if .X}}"X"{{else}}{{if .Y}}"Y"{{else}}{{if .Z}}"Z"{{end}}{{end}}{{end}}"+"`},
 	{"simple range", "{{range .X}}hello{{end}}", noError,
 		`{{range .X}}"hello"{{end}}`},
 	{"chained field range", "{{range .X.Y.Z}}hello{{end}}", noError,
 		`{{range .X.Y.Z}}"hello"{{end}}`},
 	{"nested range", "{{range .X}}hello{{range .Y}}goodbye{{end}}{{end}}", noError,
 		`{{range .X}}"hello"{{range .Y}}"goodbye"{{end}}{{end}}`},
 	{"range with else", "{{range .X}}true{{else}}false{{end}}", noError,
 		`{{range .X}}"true"{{else}}"false"{{end}}`},
 	{"range over pipeline", "{{range .X|.M}}true{{else}}false{{end}}", noError,
 		`{{range .X | .M}}"true"{{else}}"false"{{end}}`},
 	{"range []int", "{{range .SI}}{{.}}{{end}}", noError,
 		`{{range .SI}}{{.}}{{end}}`},
 	{"range 1 var", "{{range $x := .SI}}{{.}}{{end}}", noError,
 		`{{range $x := .SI}}{{.}}{{end}}`},
 	{"range 2 vars", "{{range $x, $y := .SI}}{{.}}{{end}}", noError,
 		`{{range $x, $y := .SI}}{{.}}{{end}}`},
 	{"constants", "{{range .SI 1 -3.2i true false 'a' nil}}{{end}}", noError,
 		`{{range .SI 1 -3.2i true false 'a' nil}}{{end}}`},
 	{"template", "{{template `x`}}", noError,
 		`{{template "x"}}`},
 	{"template with arg", "{{template `x` .Y}}", noError,
 		`{{template "x" .Y}}`},
 	{"with", "{{with .X}}hello{{end}}", noError,
 		`{{with .X}}"hello"{{end}}`},
 	{"with with else", "{{with .X}}hello{{else}}goodbye{{end}}", noError,
 		`{{with .X}}"hello"{{else}}"goodbye"{{end}}`},
 	// Errors.
 	{"unclosed action", "hello{{range", hasError, ""},
 	{"unmatched end", "{{end}}", hasError, ""},
 	{"missing end", "hello{{range .x}}", hasError, ""},
 	{"missing end after else", "hello{{range .x}}{{else}}", hasError, ""},
 	{"undefined function", "hello{{undefined}}", hasError, ""},
 	{"undefined variable", "{{$x}}", hasError, ""},
 	{"variable undefined after end", "{{with $x := 4}}{{end}}{{$x}}", hasError, ""},
 	{"variable undefined in template", "{{template $v}}", hasError, ""},
 	{"declare with field", "{{with $x.Y := 4}}{{end}}", hasError, ""},
 	{"template with field ref", "{{template .X}}", hasError, ""},
 	{"template with var", "{{template $v}}", hasError, ""},
 	{"invalid punctuation", "{{printf 3, 4}}", hasError, ""},
 	{"multidecl outside range", "{{with $v, $u := 3}}{{end}}", hasError, ""},
 	{"too many decls in range", "{{range $u, $v, $w := 3}}{{end}}", hasError, ""},
 	{"dot applied to parentheses", "{{printf (printf .).}}", hasError, ""},
 	{"adjacent args", "{{printf 3`x`}}", hasError, ""},
 	{"adjacent args with .", "{{printf `x`.}}", hasError, ""},
 	{"extra end after if", "{{if .X}}a{{else if .Y}}b{{end}}{{end}}", hasError, ""},
 	// Equals (and other chars) do not assignments make (yet).
 	{"bug0a", "{{$x := 0}}{{$x}}", noError, "{{$x := 0}}{{$x}}"},
 	{"bug0b", "{{$x = 1}}{{$x}}", hasError, ""},
 	{"bug0c", "{{$x ! 2}}{{$x}}", hasError, ""},
 	{"bug0d", "{{$x % 3}}{{$x}}", hasError, ""},
 	// Check the parse fails for := rather than comma.
 	{"bug0e", "{{range $x := $y := 3}}{{end}}", hasError, ""},
 	// Another bug: variable read must ignore following punctuation.
 	{"bug1a", "{{$x:=.}}{{$x!2}}", hasError, ""},                     // ! is just illegal here.
 	{"bug1b", "{{$x:=.}}{{$x+2}}", hasError, ""},                     // $x+2 should not parse as ($x) (+2).
 	{"bug1c", "{{$x:=.}}{{$x +2}}", noError, "{{$x := .}}{{$x +2}}"}, // It's OK with a space.
 }

 var builtins = map[string]interface{}{
 	"printf": fmt.Sprintf,
 }

 func testParse(doCopy bool, t *testing.T) {
 	textFormat = "%q"
 	defer func() { textFormat = "%s" }()
 	for _, test := range parseTests {
 		tmpl, err := New(test.name).Parse(test.input, "", "", make(map[string]*Tree), builtins)
 		switch {
 		case err == nil && !test.ok:
 			t.Errorf("%q: expected error; got none", test.name)
 			continue
 		case err != nil && test.ok:
 			t.Errorf("%q: unexpected error: %v", test.name, err)
 			continue
 		case err != nil && !test.ok:
 			// expected error, got one
 			if *debug {
 				fmt.Printf("%s: %s\n\t%s\n", test.name, test.input, err)
 			}
 			continue
 		}
 		var result string
 		if doCopy {
 			result = tmpl.Root.Copy().String()
 		} else {
 			result = tmpl.Root.String()
 		}
 		if result != test.result {
 			t.Errorf("%s=(%q): got\n\t%v\nexpected\n\t%v", test.name, test.input, result, test.result)
 		}
 	}
 }

 func TestParse(t *testing.T) {
 	testParse(false, t)
 }

 // Same as TestParse, but we copy the node first
 func TestParseCopy(t *testing.T) {
 	testParse(true, t)
 }

 type isEmptyTest struct {
 	name  string
 	input string
 	empty bool
 }

 var isEmptyTests = []isEmptyTest{
 	{"empty", ``, true},
 	{"nonempty", `hello`, false},
 	{"spaces only", " \t\n \t\n", true},
 	{"definition", `{{define "x"}}something{{end}}`, true},
 	{"definitions and space", "{{define `x`}}something{{end}}\n\n{{define `y`}}something{{end}}\n\n", true},
 	{"definitions and text", "{{define `x`}}something{{end}}\nx\n{{define `y`}}something{{end}}\ny\n", false},
 	{"definition and action", "{{define `x`}}something{{end}}{{if 3}}foo{{end}}", false},
 }

 func TestIsEmpty(t *testing.T) {
 	if !IsEmptyTree(nil) {
 		t.Errorf("nil tree is not empty")
 	}
 	for _, test := range isEmptyTests {
 		tree, err := New("root").Parse(test.input, "", "", make(map[string]*Tree), nil)
 		if err != nil {
 			t.Errorf("%q: unexpected error: %v", test.name, err)
 			continue
 		}
 		if empty := IsEmptyTree(tree.Root); empty != test.empty {
 			t.Errorf("%q: expected %t got %t", test.name, test.empty, empty)
 		}
 	}
 }

 func TestErrorContextWithTreeCopy(t *testing.T) {
 	tree, err := New("root").Parse("{{if true}}{{end}}", "", "", make(map[string]*Tree), nil)
 	if err != nil {
 		t.Fatalf("unexpected tree parse failure: %v", err)
 	}
 	treeCopy := tree.Copy()
 	wantLocation, wantContext := tree.ErrorContext(tree.Root.Nodes[0])
 	gotLocation, gotContext := treeCopy.ErrorContext(treeCopy.Root.Nodes[0])
 	if wantLocation != gotLocation {
 		t.Errorf("wrong error location want %q got %q", wantLocation, gotLocation)
 	}
 	if wantContext != gotContext {
 		t.Errorf("wrong error location want %q got %q", wantContext, gotContext)
 	}
 }

 // All failures, and the result is a string that must appear in the error message.
 var errorTests = []parseTest{
 	// Check line numbers are accurate.
 	{"unclosed1",
 		"line1\n{{",
 		hasError, `unclosed1:2: unexpected unclosed action in command`},
 	{"unclosed2",
 		"line1\n{{define `x`}}line2\n{{",
 		hasError, `unclosed2:3: unexpected unclosed action in command`},
 	// Specific errors.
 	{"function",
 		"{{foo}}",
 		hasError, `function "foo" not defined`},
 	{"comment",
 		"{{/*}}",
 		hasError, `unclosed comment`},
 	{"lparen",
 		"{{.X (1 2 3}}",
 		hasError, `unclosed left paren`},
 	{"rparen",
 		"{{.X 1 2 3)}}",
 		hasError, `unexpected ")"`},
 	{"space",
 		"{{`x`3}}",
 		hasError, `missing space?`},
 	{"idchar",
 		"{{a#}}",
 		hasError, `'#'`},
 	{"charconst",
 		"{{'a}}",
 		hasError, `unterminated character constant`},
 	{"stringconst",
 		`{{"a}}`,
 		hasError, `unterminated quoted string`},
 	{"rawstringconst",
 		"{{`a}}",
 		hasError, `unterminated raw quoted string`},
 	{"number",
 		"{{0xi}}",
 		hasError, `number syntax`},
 	{"multidefine",
 		"{{define `a`}}a{{end}}{{define `a`}}b{{end}}",
 		hasError, `multiple definition of template`},
 	{"eof",
 		"{{range .X}}",
 		hasError, `unexpected EOF`},
 	{"variable",
 		// Declare $x so it's defined, to avoid that error, and then check we don't parse a declaration.
 		"{{$x := 23}}{{with $x.y := 3}}{{$x 23}}{{end}}",
 		hasError, `unexpected ":="`},
 	{"multidecl",
 		"{{$a,$b,$c := 23}}",
 		hasError, `too many declarations`},
 	{"undefvar",
 		"{{$a}}",
 		hasError, `undefined variable`},
 }

 func TestErrors(t *testing.T) {
 	for _, test := range errorTests {
 		_, err := New(test.name).Parse(test.input, "", "", make(map[string]*Tree))
 		if err == nil {
 			t.Errorf("%q: expected error", test.name)
 			continue
 		}
 		if !strings.Contains(err.Error(), test.result) {
 			t.Errorf("%q: error %q does not contain %q", test.name, err, test.result)
 		}
 	}
 }
	// 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 parse

	import (
	"flag"
	"fmt"
	"strings"
	"testing"
	)

	var debug = flag.Bool("debug", false, "show the errors produced by the main tests")

	type numberTest struct {
	text string
	isInt bool
	isUint bool
	isFloat bool
	isComplex bool
	int64
	uint64
	float64
	complex128
	}

	var numberTests = []numberTest{
	// basics
	{"0", true, true, true, false, 0, 0, 0, 0},
	{"-0", true, true, true, false, 0, 0, 0, 0}, // check that -0 is a uint.
	{"73", true, true, true, false, 73, 73, 73, 0},
	{"073", true, true, true, false, 073, 073, 073, 0},
	{"0x73", true, true, true, false, 0x73, 0x73, 0x73, 0},
	{"-73", true, false, true, false, -73, 0, -73, 0},
	{"+73", true, false, true, false, 73, 0, 73, 0},
	{"100", true, true, true, false, 100, 100, 100, 0},
	{"1e9", true, true, true, false, 1e9, 1e9, 1e9, 0},
	{"-1e9", true, false, true, false, -1e9, 0, -1e9, 0},
	{"-1.2", false, false, true, false, 0, 0, -1.2, 0},
	{"1e19", false, true, true, false, 0, 1e19, 1e19, 0},
	{"-1e19", false, false, true, false, 0, 0, -1e19, 0},
	{"4i", false, false, false, true, 0, 0, 0, 4i},
	{"-1.2+4.2i", false, false, false, true, 0, 0, 0, -1.2 + 4.2i},
	{"073i", false, false, false, true, 0, 0, 0, 73i}, // not octal!
	// complex with 0 imaginary are float (and maybe integer)
	{"0i", true, true, true, true, 0, 0, 0, 0},
	{"-1.2+0i", false, false, true, true, 0, 0, -1.2, -1.2},
	{"-12+0i", true, false, true, true, -12, 0, -12, -12},
	{"13+0i", true, true, true, true, 13, 13, 13, 13},
	// funny bases
	{"0123", true, true, true, false, 0123, 0123, 0123, 0},
	{"-0x0", true, true, true, false, 0, 0, 0, 0},
	{"0xdeadbeef", true, true, true, false, 0xdeadbeef, 0xdeadbeef, 0xdeadbeef, 0},
	// character constants
	{`'a'`, true, true, true, false, 'a', 'a', 'a', 0},
	{`'\n'`, true, true, true, false, '\n', '\n', '\n', 0},
	{`'\\'`, true, true, true, false, '\\', '\\', '\\', 0},
	{`'\''`, true, true, true, false, '\'', '\'', '\'', 0},
	{`'\xFF'`, true, true, true, false, 0xFF, 0xFF, 0xFF, 0},
	{`'パ'`, true, true, true, false, 0x30d1, 0x30d1, 0x30d1, 0},
	{`'\u30d1'`, true, true, true, false, 0x30d1, 0x30d1, 0x30d1, 0},
	{`'\U000030d1'`, true, true, true, false, 0x30d1, 0x30d1, 0x30d1, 0},
	// some broken syntax
	{text: "+-2"},
	{text: "0x123."},
	{text: "1e."},
	{text: "0xi."},
	{text: "1+2."},
	{text: "'x"},
	{text: "'xx'"},
	}

	func TestNumberParse(t *testing.T) {
	for _, test := range numberTests {
	// If fmt.Sscan thinks it's complex, it's complex. We can't trust the output
	// because imaginary comes out as a number.
	var c complex128
	typ := itemNumber
	if test.text[0] == '\'' {
	typ = itemCharConstant
	} else {
	_, err := fmt.Sscan(test.text, &c)
	if err == nil {
	typ = itemComplex
	}
	}
	n, err := newNumber(0, test.text, typ)
	ok := test.isInt \|\| test.isUint \|\| test.isFloat \|\| test.isComplex
	if ok && err != nil {
	t.Errorf("unexpected error for %q: %s", test.text, err)
	continue
	}
	if !ok && err == nil {
	t.Errorf("expected error for %q", test.text)
	continue
	}
	if !ok {
	if *debug {
	fmt.Printf("%s\n\t%s\n", test.text, err)
	}
	continue
	}
	if n.IsComplex != test.isComplex {
	t.Errorf("complex incorrect for %q; should be %t", test.text, test.isComplex)
	}
	if test.isInt {
	if !n.IsInt {
	t.Errorf("expected integer for %q", test.text)
	}
	if n.Int64 != test.int64 {
	t.Errorf("int64 for %q should be %d Is %d", test.text, test.int64, n.Int64)
	}
	} else if n.IsInt {
	t.Errorf("did not expect integer for %q", test.text)
	}
	if test.isUint {
	if !n.IsUint {
	t.Errorf("expected unsigned integer for %q", test.text)
	}
	if n.Uint64 != test.uint64 {
	t.Errorf("uint64 for %q should be %d Is %d", test.text, test.uint64, n.Uint64)
	}
	} else if n.IsUint {
	t.Errorf("did not expect unsigned integer for %q", test.text)
	}
	if test.isFloat {
	if !n.IsFloat {
	t.Errorf("expected float for %q", test.text)
	}
	if n.Float64 != test.float64 {
	t.Errorf("float64 for %q should be %g Is %g", test.text, test.float64, n.Float64)
	}
	} else if n.IsFloat {
	t.Errorf("did not expect float for %q", test.text)
	}
	if test.isComplex {
	if !n.IsComplex {
	t.Errorf("expected complex for %q", test.text)
	}
	if n.Complex128 != test.complex128 {
	t.Errorf("complex128 for %q should be %g Is %g", test.text, test.complex128, n.Complex128)
	}
	} else if n.IsComplex {
	t.Errorf("did not expect complex for %q", test.text)
	}
	}
	}

	type parseTest struct {
	name string
	input string
	ok bool
	result string // what the user would see in an error message.
	}

	const (
	noError = true
	hasError = false
	)

	var parseTests = []parseTest{
	{"empty", "", noError,
	``},
	{"comment", "{{/\n\n\n/}}", noError,
	``},
	{"spaces", " \t\n", noError,
	`" \t\n"`},
	{"text", "some text", noError,
	`"some text"`},
	{"emptyAction", "{{}}", hasError,
	`{{}}`},
	{"field", "{{.X}}", noError,
	`{{.X}}`},
	{"simple command", "{{printf}}", noError,
	`{{printf}}`},
	{"$ invocation", "{{$}}", noError,
	"{{$}}"},
	{"variable invocation", "{{with $x := 3}}{{$x 23}}{{end}}", noError,
	"{{with $x := 3}}{{$x 23}}{{end}}"},
	{"variable with fields", "{{$.I}}", noError,
	"{{$.I}}"},
	{"multi-word command", "{{printf `%d` 23}}", noError,
	"{{printf `%d` 23}}"},
	{"pipeline", "{{.X\|.Y}}", noError,
	`{{.X \| .Y}}`},
	{"pipeline with decl", "{{$x := .X\|.Y}}", noError,
	`{{$x := .X \| .Y}}`},
	{"nested pipeline", "{{.X (.Y .Z) (.A \| .B .C) (.E)}}", noError,
	`{{.X (.Y .Z) (.A \| .B .C) (.E)}}`},
	{"field applied to parentheses", "{{(.Y .Z).Field}}", noError,
	`{{(.Y .Z).Field}}`},
	{"simple if", "{{if .X}}hello{{end}}", noError,
	`{{if .X}}"hello"{{end}}`},
	{"if with else", "{{if .X}}true{{else}}false{{end}}", noError,
	`{{if .X}}"true"{{else}}"false"{{end}}`},
	{"if with else if", "{{if .X}}true{{else if .Y}}false{{end}}", noError,
	`{{if .X}}"true"{{else}}{{if .Y}}"false"{{end}}{{end}}`},
	{"if else chain", "+{{if .X}}X{{else if .Y}}Y{{else if .Z}}Z{{end}}+", noError,
	`"+"{{if .X}}"X"{{else}}{{if .Y}}"Y"{{else}}{{if .Z}}"Z"{{end}}{{end}}{{end}}"+"`},
	{"simple range", "{{range .X}}hello{{end}}", noError,
	`{{range .X}}"hello"{{end}}`},
	{"chained field range", "{{range .X.Y.Z}}hello{{end}}", noError,
	`{{range .X.Y.Z}}"hello"{{end}}`},
	{"nested range", "{{range .X}}hello{{range .Y}}goodbye{{end}}{{end}}", noError,
	`{{range .X}}"hello"{{range .Y}}"goodbye"{{end}}{{end}}`},
	{"range with else", "{{range .X}}true{{else}}false{{end}}", noError,
	`{{range .X}}"true"{{else}}"false"{{end}}`},
	{"range over pipeline", "{{range .X\|.M}}true{{else}}false{{end}}", noError,
	`{{range .X \| .M}}"true"{{else}}"false"{{end}}`},
	{"range []int", "{{range .SI}}{{.}}{{end}}", noError,
	`{{range .SI}}{{.}}{{end}}`},
	{"range 1 var", "{{range $x := .SI}}{{.}}{{end}}", noError,
	`{{range $x := .SI}}{{.}}{{end}}`},
	{"range 2 vars", "{{range $x, $y := .SI}}{{.}}{{end}}", noError,
	`{{range $x, $y := .SI}}{{.}}{{end}}`},
	{"constants", "{{range .SI 1 -3.2i true false 'a' nil}}{{end}}", noError,
	`{{range .SI 1 -3.2i true false 'a' nil}}{{end}}`},
	{"template", "{{template `x`}}", noError,
	`{{template "x"}}`},
	{"template with arg", "{{template `x` .Y}}", noError,
	`{{template "x" .Y}}`},
	{"with", "{{with .X}}hello{{end}}", noError,
	`{{with .X}}"hello"{{end}}`},
	{"with with else", "{{with .X}}hello{{else}}goodbye{{end}}", noError,
	`{{with .X}}"hello"{{else}}"goodbye"{{end}}`},
	// Errors.
	{"unclosed action", "hello{{range", hasError, ""},
	{"unmatched end", "{{end}}", hasError, ""},
	{"missing end", "hello{{range .x}}", hasError, ""},
	{"missing end after else", "hello{{range .x}}{{else}}", hasError, ""},
	{"undefined function", "hello{{undefined}}", hasError, ""},
	{"undefined variable", "{{$x}}", hasError, ""},
	{"variable undefined after end", "{{with $x := 4}}{{end}}{{$x}}", hasError, ""},
	{"variable undefined in template", "{{template $v}}", hasError, ""},
	{"declare with field", "{{with $x.Y := 4}}{{end}}", hasError, ""},
	{"template with field ref", "{{template .X}}", hasError, ""},
	{"template with var", "{{template $v}}", hasError, ""},
	{"invalid punctuation", "{{printf 3, 4}}", hasError, ""},
	{"multidecl outside range", "{{with $v, $u := 3}}{{end}}", hasError, ""},
	{"too many decls in range", "{{range $u, $v, $w := 3}}{{end}}", hasError, ""},
	{"dot applied to parentheses", "{{printf (printf .).}}", hasError, ""},
	{"adjacent args", "{{printf 3`x`}}", hasError, ""},
	{"adjacent args with .", "{{printf `x`.}}", hasError, ""},
	{"extra end after if", "{{if .X}}a{{else if .Y}}b{{end}}{{end}}", hasError, ""},
	// Equals (and other chars) do not assignments make (yet).
	{"bug0a", "{{$x := 0}}{{$x}}", noError, "{{$x := 0}}{{$x}}"},
	{"bug0b", "{{$x = 1}}{{$x}}", hasError, ""},
	{"bug0c", "{{$x ! 2}}{{$x}}", hasError, ""},
	{"bug0d", "{{$x % 3}}{{$x}}", hasError, ""},
	// Check the parse fails for := rather than comma.
	{"bug0e", "{{range $x := $y := 3}}{{end}}", hasError, ""},
	// Another bug: variable read must ignore following punctuation.
	{"bug1a", "{{$x:=.}}{{$x!2}}", hasError, ""}, // ! is just illegal here.
	{"bug1b", "{{$x:=.}}{{$x+2}}", hasError, ""}, // $x+2 should not parse as ($x) (+2).
	{"bug1c", "{{$x:=.}}{{$x +2}}", noError, "{{$x := .}}{{$x +2}}"}, // It's OK with a space.
	}

	var builtins = map[string]interface{}{
	"printf": fmt.Sprintf,
	}

	func testParse(doCopy bool, t *testing.T) {
	textFormat = "%q"
	defer func() { textFormat = "%s" }()
	for _, test := range parseTests {
	tmpl, err := New(test.name).Parse(test.input, "", "", make(map[string]*Tree), builtins)
	switch {
	case err == nil && !test.ok:
	t.Errorf("%q: expected error; got none", test.name)
	continue
	case err != nil && test.ok:
	t.Errorf("%q: unexpected error: %v", test.name, err)
	continue
	case err != nil && !test.ok:
	// expected error, got one
	if *debug {
	fmt.Printf("%s: %s\n\t%s\n", test.name, test.input, err)
	}
	continue
	}
	var result string
	if doCopy {
	result = tmpl.Root.Copy().String()
	} else {
	result = tmpl.Root.String()
	}
	if result != test.result {
	t.Errorf("%s=(%q): got\n\t%v\nexpected\n\t%v", test.name, test.input, result, test.result)
	}
	}
	}

	func TestParse(t *testing.T) {
	testParse(false, t)
	}

	// Same as TestParse, but we copy the node first
	func TestParseCopy(t *testing.T) {
	testParse(true, t)
	}

	type isEmptyTest struct {
	name string
	input string
	empty bool
	}

	var isEmptyTests = []isEmptyTest{
	{"empty", ``, true},
	{"nonempty", `hello`, false},
	{"spaces only", " \t\n \t\n", true},
	{"definition", `{{define "x"}}something{{end}}`, true},
	{"definitions and space", "{{define `x`}}something{{end}}\n\n{{define `y`}}something{{end}}\n\n", true},
	{"definitions and text", "{{define `x`}}something{{end}}\nx\n{{define `y`}}something{{end}}\ny\n", false},
	{"definition and action", "{{define `x`}}something{{end}}{{if 3}}foo{{end}}", false},
	}

	func TestIsEmpty(t *testing.T) {
	if !IsEmptyTree(nil) {
	t.Errorf("nil tree is not empty")
	}
	for _, test := range isEmptyTests {
	tree, err := New("root").Parse(test.input, "", "", make(map[string]*Tree), nil)
	if err != nil {
	t.Errorf("%q: unexpected error: %v", test.name, err)
	continue
	}
	if empty := IsEmptyTree(tree.Root); empty != test.empty {
	t.Errorf("%q: expected %t got %t", test.name, test.empty, empty)
	}
	}
	}

	func TestErrorContextWithTreeCopy(t *testing.T) {
	tree, err := New("root").Parse("{{if true}}{{end}}", "", "", make(map[string]*Tree), nil)
	if err != nil {
	t.Fatalf("unexpected tree parse failure: %v", err)
	}
	treeCopy := tree.Copy()
	wantLocation, wantContext := tree.ErrorContext(tree.Root.Nodes[0])
	gotLocation, gotContext := treeCopy.ErrorContext(treeCopy.Root.Nodes[0])
	if wantLocation != gotLocation {
	t.Errorf("wrong error location want %q got %q", wantLocation, gotLocation)
	}
	if wantContext != gotContext {
	t.Errorf("wrong error location want %q got %q", wantContext, gotContext)
	}
	}

	// All failures, and the result is a string that must appear in the error message.
	var errorTests = []parseTest{
	// Check line numbers are accurate.
	{"unclosed1",
	"line1\n{{",
	hasError, `unclosed1:2: unexpected unclosed action in command`},
	{"unclosed2",
	"line1\n{{define `x`}}line2\n{{",
	hasError, `unclosed2:3: unexpected unclosed action in command`},
	// Specific errors.
	{"function",
	"{{foo}}",
	hasError, `function "foo" not defined`},
	{"comment",
	"{{/*}}",
	hasError, `unclosed comment`},
	{"lparen",
	"{{.X (1 2 3}}",
	hasError, `unclosed left paren`},
	{"rparen",
	"{{.X 1 2 3)}}",
	hasError, `unexpected ")"`},
	{"space",
	"{{`x`3}}",
	hasError, `missing space?`},
	{"idchar",
	"{{a#}}",
	hasError, `'#'`},
	{"charconst",
	"{{'a}}",
	hasError, `unterminated character constant`},
	{"stringconst",
	`{{"a}}`,
	hasError, `unterminated quoted string`},
	{"rawstringconst",
	"{{`a}}",
	hasError, `unterminated raw quoted string`},
	{"number",
	"{{0xi}}",
	hasError, `number syntax`},
	{"multidefine",
	"{{define `a`}}a{{end}}{{define `a`}}b{{end}}",
	hasError, `multiple definition of template`},
	{"eof",
	"{{range .X}}",
	hasError, `unexpected EOF`},
	{"variable",
	// Declare $x so it's defined, to avoid that error, and then check we don't parse a declaration.
	"{{$x := 23}}{{with $x.y := 3}}{{$x 23}}{{end}}",
	hasError, `unexpected ":="`},
	{"multidecl",
	"{{$a,$b,$c := 23}}",
	hasError, `too many declarations`},
	{"undefvar",
	"{{$a}}",
	hasError, `undefined variable`},
	}

	func TestErrors(t *testing.T) {
	for _, test := range errorTests {
	_, err := New(test.name).Parse(test.input, "", "", make(map[string]*Tree))
	if err == nil {
	t.Errorf("%q: expected error", test.name)
	continue
	}
	if !strings.Contains(err.Error(), test.result) {
	t.Errorf("%q: error %q does not contain %q", test.name, err, test.result)
	}
	}
	}