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-rw-r--r--src/pkg/template/parse/Makefile14
-rw-r--r--src/pkg/template/parse/lex.go474
-rw-r--r--src/pkg/template/parse/lex_test.go209
-rw-r--r--src/pkg/template/parse/node.go469
-rw-r--r--src/pkg/template/parse/parse.go436
-rw-r--r--src/pkg/template/parse/parse_test.go259
-rw-r--r--src/pkg/template/parse/set.go50
7 files changed, 1911 insertions, 0 deletions
diff --git a/src/pkg/template/parse/Makefile b/src/pkg/template/parse/Makefile
new file mode 100644
index 000000000..fe6585809
--- /dev/null
+++ b/src/pkg/template/parse/Makefile
@@ -0,0 +1,14 @@
+# 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.
+
+include ../../../Make.inc
+
+TARG=template/parse
+GOFILES=\
+ lex.go\
+ node.go\
+ parse.go\
+ set.go\
+
+include ../../../Make.pkg
diff --git a/src/pkg/template/parse/lex.go b/src/pkg/template/parse/lex.go
new file mode 100644
index 000000000..7ec4e920b
--- /dev/null
+++ b/src/pkg/template/parse/lex.go
@@ -0,0 +1,474 @@
+// 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 (
+ "fmt"
+ "strings"
+ "unicode"
+ "utf8"
+)
+
+// item represents a token or text string returned from the scanner.
+type item struct {
+ typ itemType
+ val string
+}
+
+func (i item) String() string {
+ switch {
+ case i.typ == itemEOF:
+ return "EOF"
+ case i.typ == itemError:
+ return i.val
+ case i.typ > itemKeyword:
+ return fmt.Sprintf("<%s>", i.val)
+ case len(i.val) > 10:
+ return fmt.Sprintf("%.10q...", i.val)
+ }
+ return fmt.Sprintf("%q", i.val)
+}
+
+// itemType identifies the type of lex items.
+type itemType int
+
+const (
+ itemError itemType = iota // error occurred; value is text of error
+ itemBool // boolean constant
+ itemChar // printable ASCII character; grab bag for comma etc.
+ itemCharConstant // character constant
+ itemComplex // complex constant (1+2i); imaginary is just a number
+ itemColonEquals // colon-equals (':=') introducing a declaration
+ itemEOF
+ itemField // alphanumeric identifier, starting with '.', possibly chained ('.x.y')
+ itemIdentifier // alphanumeric identifier
+ itemLeftDelim // left action delimiter
+ itemNumber // simple number, including imaginary
+ itemPipe // pipe symbol
+ itemRawString // raw quoted string (includes quotes)
+ itemRightDelim // right action delimiter
+ itemString // quoted string (includes quotes)
+ itemText // plain text
+ itemVariable // variable starting with '$', such as '$' or '$1' or '$hello'.
+ // Keywords appear after all the rest.
+ itemKeyword // used only to delimit the keywords
+ itemDot // the cursor, spelled '.'.
+ itemDefine // define keyword
+ itemElse // else keyword
+ itemEnd // end keyword
+ itemIf // if keyword
+ itemRange // range keyword
+ itemTemplate // template keyword
+ itemWith // with keyword
+)
+
+// Make the types prettyprint.
+var itemName = map[itemType]string{
+ itemError: "error",
+ itemBool: "bool",
+ itemChar: "char",
+ itemCharConstant: "charconst",
+ itemComplex: "complex",
+ itemColonEquals: ":=",
+ itemEOF: "EOF",
+ itemField: "field",
+ itemIdentifier: "identifier",
+ itemLeftDelim: "left delim",
+ itemNumber: "number",
+ itemPipe: "pipe",
+ itemRawString: "raw string",
+ itemRightDelim: "right delim",
+ itemString: "string",
+ itemVariable: "variable",
+ // keywords
+ itemDot: ".",
+ itemDefine: "define",
+ itemElse: "else",
+ itemIf: "if",
+ itemEnd: "end",
+ itemRange: "range",
+ itemTemplate: "template",
+ itemWith: "with",
+}
+
+func (i itemType) String() string {
+ s := itemName[i]
+ if s == "" {
+ return fmt.Sprintf("item%d", int(i))
+ }
+ return s
+}
+
+var key = map[string]itemType{
+ ".": itemDot,
+ "define": itemDefine,
+ "else": itemElse,
+ "end": itemEnd,
+ "if": itemIf,
+ "range": itemRange,
+ "template": itemTemplate,
+ "with": itemWith,
+}
+
+const eof = -1
+
+// stateFn represents the state of the scanner as a function that returns the next state.
+type stateFn func(*lexer) stateFn
+
+// lexer holds the state of the scanner.
+type lexer struct {
+ name string // the name of the input; used only for error reports.
+ input string // the string being scanned.
+ state stateFn // the next lexing function to enter
+ pos int // current position in the input.
+ start int // start position of this item.
+ width int // width of last rune read from input.
+ items chan item // channel of scanned items.
+}
+
+// next returns the next rune in the input.
+func (l *lexer) next() (rune int) {
+ if l.pos >= len(l.input) {
+ l.width = 0
+ return eof
+ }
+ rune, l.width = utf8.DecodeRuneInString(l.input[l.pos:])
+ l.pos += l.width
+ return rune
+}
+
+// peek returns but does not consume the next rune in the input.
+func (l *lexer) peek() int {
+ rune := l.next()
+ l.backup()
+ return rune
+}
+
+// backup steps back one rune. Can only be called once per call of next.
+func (l *lexer) backup() {
+ l.pos -= l.width
+}
+
+// emit passes an item back to the client.
+func (l *lexer) emit(t itemType) {
+ l.items <- item{t, l.input[l.start:l.pos]}
+ l.start = l.pos
+}
+
+// ignore skips over the pending input before this point.
+func (l *lexer) ignore() {
+ l.start = l.pos
+}
+
+// accept consumes the next rune if it's from the valid set.
+func (l *lexer) accept(valid string) bool {
+ if strings.IndexRune(valid, l.next()) >= 0 {
+ return true
+ }
+ l.backup()
+ return false
+}
+
+// acceptRun consumes a run of runes from the valid set.
+func (l *lexer) acceptRun(valid string) {
+ for strings.IndexRune(valid, l.next()) >= 0 {
+ }
+ l.backup()
+}
+
+// lineNumber reports which line we're on. Doing it this way
+// means we don't have to worry about peek double counting.
+func (l *lexer) lineNumber() int {
+ return 1 + strings.Count(l.input[:l.pos], "\n")
+}
+
+// error returns an error token and terminates the scan by passing
+// back a nil pointer that will be the next state, terminating l.run.
+func (l *lexer) errorf(format string, args ...interface{}) stateFn {
+ l.items <- item{itemError, fmt.Sprintf(format, args...)}
+ return nil
+}
+
+// nextItem returns the next item from the input.
+func (l *lexer) nextItem() item {
+ for {
+ select {
+ case item := <-l.items:
+ return item
+ default:
+ l.state = l.state(l)
+ }
+ }
+ panic("not reached")
+}
+
+// lex creates a new scanner for the input string.
+func lex(name, input string) *lexer {
+ l := &lexer{
+ name: name,
+ input: input,
+ state: lexText,
+ items: make(chan item, 2), // Two items of buffering is sufficient for all state functions
+ }
+ return l
+}
+
+// state functions
+
+const (
+ leftDelim = "{{"
+ rightDelim = "}}"
+ leftComment = "{{/*"
+ rightComment = "*/}}"
+)
+
+// lexText scans until an opening action delimiter, "{{".
+func lexText(l *lexer) stateFn {
+ for {
+ if strings.HasPrefix(l.input[l.pos:], leftDelim) {
+ if l.pos > l.start {
+ l.emit(itemText)
+ }
+ return lexLeftDelim
+ }
+ if l.next() == eof {
+ break
+ }
+ }
+ // Correctly reached EOF.
+ if l.pos > l.start {
+ l.emit(itemText)
+ }
+ l.emit(itemEOF)
+ return nil
+}
+
+// lexLeftDelim scans the left delimiter, which is known to be present.
+func lexLeftDelim(l *lexer) stateFn {
+ if strings.HasPrefix(l.input[l.pos:], leftComment) {
+ return lexComment
+ }
+ l.pos += len(leftDelim)
+ l.emit(itemLeftDelim)
+ return lexInsideAction
+}
+
+// lexComment scans a comment. The left comment marker is known to be present.
+func lexComment(l *lexer) stateFn {
+ i := strings.Index(l.input[l.pos:], rightComment)
+ if i < 0 {
+ return l.errorf("unclosed comment")
+ }
+ l.pos += i + len(rightComment)
+ l.ignore()
+ return lexText
+}
+
+// lexRightDelim scans the right delimiter, which is known to be present.
+func lexRightDelim(l *lexer) stateFn {
+ l.pos += len(rightDelim)
+ l.emit(itemRightDelim)
+ return lexText
+}
+
+// lexInsideAction scans the elements inside action delimiters.
+func lexInsideAction(l *lexer) stateFn {
+ // Either number, quoted string, or identifier.
+ // Spaces separate and are ignored.
+ // Pipe symbols separate and are emitted.
+ for {
+ if strings.HasPrefix(l.input[l.pos:], rightDelim) {
+ return lexRightDelim
+ }
+ switch r := l.next(); {
+ case r == eof || r == '\n':
+ return l.errorf("unclosed action")
+ case isSpace(r):
+ l.ignore()
+ case r == ':':
+ if l.next() != '=' {
+ return l.errorf("expected :=")
+ }
+ l.emit(itemColonEquals)
+ case r == '|':
+ l.emit(itemPipe)
+ case r == '"':
+ return lexQuote
+ case r == '`':
+ return lexRawQuote
+ case r == '$':
+ return lexIdentifier
+ case r == '\'':
+ return lexChar
+ case r == '.':
+ // special look-ahead for ".field" so we don't break l.backup().
+ if l.pos < len(l.input) {
+ r := l.input[l.pos]
+ if r < '0' || '9' < r {
+ return lexIdentifier // itemDot comes from the keyword table.
+ }
+ }
+ fallthrough // '.' can start a number.
+ case r == '+' || r == '-' || ('0' <= r && r <= '9'):
+ l.backup()
+ return lexNumber
+ case isAlphaNumeric(r):
+ l.backup()
+ return lexIdentifier
+ case r <= unicode.MaxASCII && unicode.IsPrint(r):
+ l.emit(itemChar)
+ return lexInsideAction
+ default:
+ return l.errorf("unrecognized character in action: %#U", r)
+ }
+ }
+ return nil
+}
+
+// lexIdentifier scans an alphanumeric or field.
+func lexIdentifier(l *lexer) stateFn {
+Loop:
+ for {
+ switch r := l.next(); {
+ case isAlphaNumeric(r):
+ // absorb.
+ case r == '.' && (l.input[l.start] == '.' || l.input[l.start] == '$'):
+ // field chaining; absorb into one token.
+ default:
+ l.backup()
+ word := l.input[l.start:l.pos]
+ switch {
+ case key[word] > itemKeyword:
+ l.emit(key[word])
+ case word[0] == '.':
+ l.emit(itemField)
+ case word[0] == '$':
+ l.emit(itemVariable)
+ case word == "true", word == "false":
+ l.emit(itemBool)
+ default:
+ l.emit(itemIdentifier)
+ }
+ break Loop
+ }
+ }
+ return lexInsideAction
+}
+
+// lexChar scans a character constant. The initial quote is already
+// scanned. Syntax checking is done by the parse.
+func lexChar(l *lexer) stateFn {
+Loop:
+ for {
+ switch l.next() {
+ case '\\':
+ if r := l.next(); r != eof && r != '\n' {
+ break
+ }
+ fallthrough
+ case eof, '\n':
+ return l.errorf("unterminated character constant")
+ case '\'':
+ break Loop
+ }
+ }
+ l.emit(itemCharConstant)
+ return lexInsideAction
+}
+
+// lexNumber scans a number: decimal, octal, hex, float, or imaginary. This
+// isn't a perfect number scanner - for instance it accepts "." and "0x0.2"
+// and "089" - but when it's wrong the input is invalid and the parser (via
+// strconv) will notice.
+func lexNumber(l *lexer) stateFn {
+ if !l.scanNumber() {
+ return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+ }
+ if sign := l.peek(); sign == '+' || sign == '-' {
+ // Complex: 1+2i. No spaces, must end in 'i'.
+ if !l.scanNumber() || l.input[l.pos-1] != 'i' {
+ return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+ }
+ l.emit(itemComplex)
+ } else {
+ l.emit(itemNumber)
+ }
+ return lexInsideAction
+}
+
+func (l *lexer) scanNumber() bool {
+ // Optional leading sign.
+ l.accept("+-")
+ // Is it hex?
+ digits := "0123456789"
+ if l.accept("0") && l.accept("xX") {
+ digits = "0123456789abcdefABCDEF"
+ }
+ l.acceptRun(digits)
+ if l.accept(".") {
+ l.acceptRun(digits)
+ }
+ if l.accept("eE") {
+ l.accept("+-")
+ l.acceptRun("0123456789")
+ }
+ // Is it imaginary?
+ l.accept("i")
+ // Next thing mustn't be alphanumeric.
+ if isAlphaNumeric(l.peek()) {
+ l.next()
+ return false
+ }
+ return true
+}
+
+// lexQuote scans a quoted string.
+func lexQuote(l *lexer) stateFn {
+Loop:
+ for {
+ switch l.next() {
+ case '\\':
+ if r := l.next(); r != eof && r != '\n' {
+ break
+ }
+ fallthrough
+ case eof, '\n':
+ return l.errorf("unterminated quoted string")
+ case '"':
+ break Loop
+ }
+ }
+ l.emit(itemString)
+ return lexInsideAction
+}
+
+// lexRawQuote scans a raw quoted string.
+func lexRawQuote(l *lexer) stateFn {
+Loop:
+ for {
+ switch l.next() {
+ case eof, '\n':
+ return l.errorf("unterminated raw quoted string")
+ case '`':
+ break Loop
+ }
+ }
+ l.emit(itemRawString)
+ return lexInsideAction
+}
+
+// isSpace reports whether r is a space character.
+func isSpace(r int) bool {
+ switch r {
+ case ' ', '\t', '\n', '\r':
+ return true
+ }
+ return false
+}
+
+// isAlphaNumeric reports whether r is an alphabetic, digit, or underscore.
+func isAlphaNumeric(r int) bool {
+ return r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r)
+}
diff --git a/src/pkg/template/parse/lex_test.go b/src/pkg/template/parse/lex_test.go
new file mode 100644
index 000000000..2ad91d5fa
--- /dev/null
+++ b/src/pkg/template/parse/lex_test.go
@@ -0,0 +1,209 @@
+// 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 (
+ "reflect"
+ "testing"
+)
+
+type lexTest struct {
+ name string
+ input string
+ items []item
+}
+
+var (
+ tEOF = item{itemEOF, ""}
+ tLeft = item{itemLeftDelim, "{{"}
+ tRight = item{itemRightDelim, "}}"}
+ tRange = item{itemRange, "range"}
+ tPipe = item{itemPipe, "|"}
+ tFor = item{itemIdentifier, "for"}
+ tQuote = item{itemString, `"abc \n\t\" "`}
+ raw = "`" + `abc\n\t\" ` + "`"
+ tRawQuote = item{itemRawString, raw}
+)
+
+var lexTests = []lexTest{
+ {"empty", "", []item{tEOF}},
+ {"spaces", " \t\n", []item{{itemText, " \t\n"}, tEOF}},
+ {"text", `now is the time`, []item{{itemText, "now is the time"}, tEOF}},
+ {"text with comment", "hello-{{/* this is a comment */}}-world", []item{
+ {itemText, "hello-"},
+ {itemText, "-world"},
+ tEOF,
+ }},
+ {"punctuation", "{{,@%}}", []item{
+ tLeft,
+ {itemChar, ","},
+ {itemChar, "@"},
+ {itemChar, "%"},
+ tRight,
+ tEOF,
+ }},
+ {"empty action", `{{}}`, []item{tLeft, tRight, tEOF}},
+ {"for", `{{for }}`, []item{tLeft, tFor, tRight, tEOF}},
+ {"quote", `{{"abc \n\t\" "}}`, []item{tLeft, tQuote, tRight, tEOF}},
+ {"raw quote", "{{" + raw + "}}", []item{tLeft, tRawQuote, tRight, tEOF}},
+ {"numbers", "{{1 02 0x14 -7.2i 1e3 +1.2e-4 4.2i 1+2i}}", []item{
+ tLeft,
+ {itemNumber, "1"},
+ {itemNumber, "02"},
+ {itemNumber, "0x14"},
+ {itemNumber, "-7.2i"},
+ {itemNumber, "1e3"},
+ {itemNumber, "+1.2e-4"},
+ {itemNumber, "4.2i"},
+ {itemComplex, "1+2i"},
+ tRight,
+ tEOF,
+ }},
+ {"characters", `{{'a' '\n' '\'' '\\' '\u00FF' '\xFF' '本'}}`, []item{
+ tLeft,
+ {itemCharConstant, `'a'`},
+ {itemCharConstant, `'\n'`},
+ {itemCharConstant, `'\''`},
+ {itemCharConstant, `'\\'`},
+ {itemCharConstant, `'\u00FF'`},
+ {itemCharConstant, `'\xFF'`},
+ {itemCharConstant, `'本'`},
+ tRight,
+ tEOF,
+ }},
+ {"bools", "{{true false}}", []item{
+ tLeft,
+ {itemBool, "true"},
+ {itemBool, "false"},
+ tRight,
+ tEOF,
+ }},
+ {"dot", "{{.}}", []item{
+ tLeft,
+ {itemDot, "."},
+ tRight,
+ tEOF,
+ }},
+ {"dots", "{{.x . .2 .x.y}}", []item{
+ tLeft,
+ {itemField, ".x"},
+ {itemDot, "."},
+ {itemNumber, ".2"},
+ {itemField, ".x.y"},
+ tRight,
+ tEOF,
+ }},
+ {"keywords", "{{range if else end with}}", []item{
+ tLeft,
+ {itemRange, "range"},
+ {itemIf, "if"},
+ {itemElse, "else"},
+ {itemEnd, "end"},
+ {itemWith, "with"},
+ tRight,
+ tEOF,
+ }},
+ {"variables", "{{$c := printf $ $hello $23 $ $var.Field .Method}}", []item{
+ tLeft,
+ {itemVariable, "$c"},
+ {itemColonEquals, ":="},
+ {itemIdentifier, "printf"},
+ {itemVariable, "$"},
+ {itemVariable, "$hello"},
+ {itemVariable, "$23"},
+ {itemVariable, "$"},
+ {itemVariable, "$var.Field"},
+ {itemField, ".Method"},
+ tRight,
+ tEOF,
+ }},
+ {"pipeline", `intro {{echo hi 1.2 |noargs|args 1 "hi"}} outro`, []item{
+ {itemText, "intro "},
+ tLeft,
+ {itemIdentifier, "echo"},
+ {itemIdentifier, "hi"},
+ {itemNumber, "1.2"},
+ tPipe,
+ {itemIdentifier, "noargs"},
+ tPipe,
+ {itemIdentifier, "args"},
+ {itemNumber, "1"},
+ {itemString, `"hi"`},
+ tRight,
+ {itemText, " outro"},
+ tEOF,
+ }},
+ {"declaration", "{{$v := 3}}", []item{
+ tLeft,
+ {itemVariable, "$v"},
+ {itemColonEquals, ":="},
+ {itemNumber, "3"},
+ tRight,
+ tEOF,
+ }},
+ {"2 declarations", "{{$v , $w := 3}}", []item{
+ tLeft,
+ {itemVariable, "$v"},
+ {itemChar, ","},
+ {itemVariable, "$w"},
+ {itemColonEquals, ":="},
+ {itemNumber, "3"},
+ tRight,
+ tEOF,
+ }},
+ // errors
+ {"badchar", "#{{\x01}}", []item{
+ {itemText, "#"},
+ tLeft,
+ {itemError, "unrecognized character in action: U+0001"},
+ }},
+ {"unclosed action", "{{\n}}", []item{
+ tLeft,
+ {itemError, "unclosed action"},
+ }},
+ {"EOF in action", "{{range", []item{
+ tLeft,
+ tRange,
+ {itemError, "unclosed action"},
+ }},
+ {"unclosed quote", "{{\"\n\"}}", []item{
+ tLeft,
+ {itemError, "unterminated quoted string"},
+ }},
+ {"unclosed raw quote", "{{`xx\n`}}", []item{
+ tLeft,
+ {itemError, "unterminated raw quoted string"},
+ }},
+ {"unclosed char constant", "{{'\n}}", []item{
+ tLeft,
+ {itemError, "unterminated character constant"},
+ }},
+ {"bad number", "{{3k}}", []item{
+ tLeft,
+ {itemError, `bad number syntax: "3k"`},
+ }},
+}
+
+// collect gathers the emitted items into a slice.
+func collect(t *lexTest) (items []item) {
+ l := lex(t.name, t.input)
+ for {
+ item := l.nextItem()
+ items = append(items, item)
+ if item.typ == itemEOF || item.typ == itemError {
+ break
+ }
+ }
+ return
+}
+
+func TestLex(t *testing.T) {
+ for _, test := range lexTests {
+ items := collect(&test)
+ if !reflect.DeepEqual(items, test.items) {
+ t.Errorf("%s: got\n\t%v\nexpected\n\t%v", test.name, items, test.items)
+ }
+ }
+}
diff --git a/src/pkg/template/parse/node.go b/src/pkg/template/parse/node.go
new file mode 100644
index 000000000..a917418dc
--- /dev/null
+++ b/src/pkg/template/parse/node.go
@@ -0,0 +1,469 @@
+// 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.
+
+// Parse nodes.
+
+package parse
+
+import (
+ "bytes"
+ "fmt"
+ "os"
+ "strconv"
+ "strings"
+)
+
+// A node is an element in the parse tree. The interface is trivial.
+type Node interface {
+ Type() NodeType
+ String() string
+}
+
+// NodeType identifies the type of a parse tree node.
+type NodeType int
+
+// Type returns itself and provides an easy default implementation
+// for embedding in a Node. Embedded in all non-trivial Nodes.
+func (t NodeType) Type() NodeType {
+ return t
+}
+
+const (
+ NodeText NodeType = iota // Plain text.
+ NodeAction // A simple action such as field evaluation.
+ NodeBool // A boolean constant.
+ NodeCommand // An element of a pipeline.
+ NodeDot // The cursor, dot.
+ NodeElse // An else action.
+ NodeEnd // An end action.
+ NodeField // A field or method name.
+ NodeIdentifier // An identifier; always a function name.
+ NodeIf // An if action.
+ NodeList // A list of Nodes.
+ NodeNumber // A numerical constant.
+ NodePipe // A pipeline of commands.
+ NodeRange // A range action.
+ NodeString // A string constant.
+ NodeTemplate // A template invocation action.
+ NodeVariable // A $ variable.
+ NodeWith // A with action.
+)
+
+// Nodes.
+
+// ListNode holds a sequence of nodes.
+type ListNode struct {
+ NodeType
+ Nodes []Node // The element nodes in lexical order.
+}
+
+func newList() *ListNode {
+ return &ListNode{NodeType: NodeList}
+}
+
+func (l *ListNode) append(n Node) {
+ l.Nodes = append(l.Nodes, n)
+}
+
+func (l *ListNode) String() string {
+ b := new(bytes.Buffer)
+ fmt.Fprint(b, "[")
+ for _, n := range l.Nodes {
+ fmt.Fprint(b, n)
+ }
+ fmt.Fprint(b, "]")
+ return b.String()
+}
+
+// TextNode holds plain text.
+type TextNode struct {
+ NodeType
+ Text []byte // The text; may span newlines.
+}
+
+func newText(text string) *TextNode {
+ return &TextNode{NodeType: NodeText, Text: []byte(text)}
+}
+
+func (t *TextNode) String() string {
+ return fmt.Sprintf("(text: %q)", t.Text)
+}
+
+// PipeNode holds a pipeline with optional declaration
+type PipeNode struct {
+ NodeType
+ Line int // The line number in the input.
+ Decl []*VariableNode // Variable declarations in lexical order.
+ Cmds []*CommandNode // The commands in lexical order.
+}
+
+func newPipeline(line int, decl []*VariableNode) *PipeNode {
+ return &PipeNode{NodeType: NodePipe, Line: line, Decl: decl}
+}
+
+func (p *PipeNode) append(command *CommandNode) {
+ p.Cmds = append(p.Cmds, command)
+}
+
+func (p *PipeNode) String() string {
+ if p.Decl != nil {
+ return fmt.Sprintf("%v := %v", p.Decl, p.Cmds)
+ }
+ return fmt.Sprintf("%v", p.Cmds)
+}
+
+// ActionNode holds an action (something bounded by delimiters).
+// Control actions have their own nodes; ActionNode represents simple
+// ones such as field evaluations.
+type ActionNode struct {
+ NodeType
+ Line int // The line number in the input.
+ Pipe *PipeNode // The pipeline in the action.
+}
+
+func newAction(line int, pipe *PipeNode) *ActionNode {
+ return &ActionNode{NodeType: NodeAction, Line: line, Pipe: pipe}
+}
+
+func (a *ActionNode) String() string {
+ return fmt.Sprintf("(action: %v)", a.Pipe)
+}
+
+// CommandNode holds a command (a pipeline inside an evaluating action).
+type CommandNode struct {
+ NodeType
+ Args []Node // Arguments in lexical order: Identifier, field, or constant.
+}
+
+func newCommand() *CommandNode {
+ return &CommandNode{NodeType: NodeCommand}
+}
+
+func (c *CommandNode) append(arg Node) {
+ c.Args = append(c.Args, arg)
+}
+
+func (c *CommandNode) String() string {
+ return fmt.Sprintf("(command: %v)", c.Args)
+}
+
+// IdentifierNode holds an identifier.
+type IdentifierNode struct {
+ NodeType
+ Ident string // The identifier's name.
+}
+
+// NewIdentifier returns a new IdentifierNode with the given identifier name.
+func NewIdentifier(ident string) *IdentifierNode {
+ return &IdentifierNode{NodeType: NodeIdentifier, Ident: ident}
+}
+
+func (i *IdentifierNode) String() string {
+ return fmt.Sprintf("I=%s", i.Ident)
+}
+
+// VariableNode holds a list of variable names. The dollar sign is
+// part of the name.
+type VariableNode struct {
+ NodeType
+ Ident []string // Variable names in lexical order.
+}
+
+func newVariable(ident string) *VariableNode {
+ return &VariableNode{NodeType: NodeVariable, Ident: strings.Split(ident, ".")}
+}
+
+func (v *VariableNode) String() string {
+ return fmt.Sprintf("V=%s", v.Ident)
+}
+
+// DotNode holds the special identifier '.'. It is represented by a nil pointer.
+type DotNode bool
+
+func newDot() *DotNode {
+ return nil
+}
+
+func (d *DotNode) Type() NodeType {
+ return NodeDot
+}
+
+func (d *DotNode) String() string {
+ return "{{<.>}}"
+}
+
+// FieldNode holds a field (identifier starting with '.').
+// The names may be chained ('.x.y').
+// The period is dropped from each ident.
+type FieldNode struct {
+ NodeType
+ Ident []string // The identifiers in lexical order.
+}
+
+func newField(ident string) *FieldNode {
+ return &FieldNode{NodeType: NodeField, Ident: strings.Split(ident[1:], ".")} // [1:] to drop leading period
+}
+
+func (f *FieldNode) String() string {
+ return fmt.Sprintf("F=%s", f.Ident)
+}
+
+// BoolNode holds a boolean constant.
+type BoolNode struct {
+ NodeType
+ True bool // The value of the boolean constant.
+}
+
+func newBool(true bool) *BoolNode {
+ return &BoolNode{NodeType: NodeBool, True: true}
+}
+
+func (b *BoolNode) String() string {
+ return fmt.Sprintf("B=%t", b.True)
+}
+
+// NumberNode holds a number: signed or unsigned integer, float, or complex.
+// The value is parsed and stored under all the types that can represent the value.
+// This simulates in a small amount of code the behavior of Go's ideal constants.
+type NumberNode struct {
+ NodeType
+ IsInt bool // Number has an integral value.
+ IsUint bool // Number has an unsigned integral value.
+ IsFloat bool // Number has a floating-point value.
+ IsComplex bool // Number is complex.
+ Int64 int64 // The signed integer value.
+ Uint64 uint64 // The unsigned integer value.
+ Float64 float64 // The floating-point value.
+ Complex128 complex128 // The complex value.
+ Text string // The original textual representation from the input.
+}
+
+func newNumber(text string, typ itemType) (*NumberNode, os.Error) {
+ n := &NumberNode{NodeType: NodeNumber, Text: text}
+ switch typ {
+ case itemCharConstant:
+ rune, _, tail, err := strconv.UnquoteChar(text[1:], text[0])
+ if err != nil {
+ return nil, err
+ }
+ if tail != "'" {
+ return nil, fmt.Errorf("malformed character constant: %s", text)
+ }
+ n.Int64 = int64(rune)
+ n.IsInt = true
+ n.Uint64 = uint64(rune)
+ n.IsUint = true
+ n.Float64 = float64(rune) // odd but those are the rules.
+ n.IsFloat = true
+ return n, nil
+ case itemComplex:
+ // fmt.Sscan can parse the pair, so let it do the work.
+ if _, err := fmt.Sscan(text, &n.Complex128); err != nil {
+ return nil, err
+ }
+ n.IsComplex = true
+ n.simplifyComplex()
+ return n, nil
+ }
+ // Imaginary constants can only be complex unless they are zero.
+ if len(text) > 0 && text[len(text)-1] == 'i' {
+ f, err := strconv.Atof64(text[:len(text)-1])
+ if err == nil {
+ n.IsComplex = true
+ n.Complex128 = complex(0, f)
+ n.simplifyComplex()
+ return n, nil
+ }
+ }
+ // Do integer test first so we get 0x123 etc.
+ u, err := strconv.Btoui64(text, 0) // will fail for -0; fixed below.
+ if err == nil {
+ n.IsUint = true
+ n.Uint64 = u
+ }
+ i, err := strconv.Btoi64(text, 0)
+ if err == nil {
+ n.IsInt = true
+ n.Int64 = i
+ if i == 0 {
+ n.IsUint = true // in case of -0.
+ n.Uint64 = u
+ }
+ }
+ // If an integer extraction succeeded, promote the float.
+ if n.IsInt {
+ n.IsFloat = true
+ n.Float64 = float64(n.Int64)
+ } else if n.IsUint {
+ n.IsFloat = true
+ n.Float64 = float64(n.Uint64)
+ } else {
+ f, err := strconv.Atof64(text)
+ if err == nil {
+ n.IsFloat = true
+ n.Float64 = f
+ // If a floating-point extraction succeeded, extract the int if needed.
+ if !n.IsInt && float64(int64(f)) == f {
+ n.IsInt = true
+ n.Int64 = int64(f)
+ }
+ if !n.IsUint && float64(uint64(f)) == f {
+ n.IsUint = true
+ n.Uint64 = uint64(f)
+ }
+ }
+ }
+ if !n.IsInt && !n.IsUint && !n.IsFloat {
+ return nil, fmt.Errorf("illegal number syntax: %q", text)
+ }
+ return n, nil
+}
+
+// simplifyComplex pulls out any other types that are represented by the complex number.
+// These all require that the imaginary part be zero.
+func (n *NumberNode) simplifyComplex() {
+ n.IsFloat = imag(n.Complex128) == 0
+ if n.IsFloat {
+ n.Float64 = real(n.Complex128)
+ n.IsInt = float64(int64(n.Float64)) == n.Float64
+ if n.IsInt {
+ n.Int64 = int64(n.Float64)
+ }
+ n.IsUint = float64(uint64(n.Float64)) == n.Float64
+ if n.IsUint {
+ n.Uint64 = uint64(n.Float64)
+ }
+ }
+}
+
+func (n *NumberNode) String() string {
+ return fmt.Sprintf("N=%s", n.Text)
+}
+
+// StringNode holds a string constant. The value has been "unquoted".
+type StringNode struct {
+ NodeType
+ Quoted string // The original text of the string, with quotes.
+ Text string // The string, after quote processing.
+}
+
+func newString(orig, text string) *StringNode {
+ return &StringNode{NodeType: NodeString, Quoted: orig, Text: text}
+}
+
+func (s *StringNode) String() string {
+ return fmt.Sprintf("S=%#q", s.Text)
+}
+
+// EndNode represents an {{end}} action. It is represented by a nil pointer.
+type EndNode bool
+
+func newEnd() *EndNode {
+ return nil
+}
+
+func (e *EndNode) Type() NodeType {
+ return NodeEnd
+}
+
+func (e *EndNode) String() string {
+ return "{{end}}"
+}
+
+// ElseNode represents an {{else}} action.
+type ElseNode struct {
+ NodeType
+ Line int // The line number in the input.
+}
+
+func newElse(line int) *ElseNode {
+ return &ElseNode{NodeType: NodeElse, Line: line}
+}
+
+func (e *ElseNode) Type() NodeType {
+ return NodeElse
+}
+
+func (e *ElseNode) String() string {
+ return "{{else}}"
+}
+
+// IfNode represents an {{if}} action and its commands.
+type IfNode struct {
+ NodeType
+ Line int // The line number in the input.
+ Pipe *PipeNode // The pipeline to be evaluated.
+ List *ListNode // What to execute if the value is non-empty.
+ ElseList *ListNode // What to execute if the value is empty (nil if absent).
+}
+
+func newIf(line int, pipe *PipeNode, list, elseList *ListNode) *IfNode {
+ return &IfNode{NodeType: NodeIf, Line: line, Pipe: pipe, List: list, ElseList: elseList}
+}
+
+func (i *IfNode) String() string {
+ if i.ElseList != nil {
+ return fmt.Sprintf("({{if %s}} %s {{else}} %s)", i.Pipe, i.List, i.ElseList)
+ }
+ return fmt.Sprintf("({{if %s}} %s)", i.Pipe, i.List)
+}
+
+// RangeNode represents a {{range}} action and its commands.
+type RangeNode struct {
+ NodeType
+ Line int // The line number in the input.
+ Pipe *PipeNode // The pipeline to be evaluated.
+ List *ListNode // What to execute if the value is non-empty.
+ ElseList *ListNode // What to execute if the value is empty (nil if absent).
+}
+
+func newRange(line int, pipe *PipeNode, list, elseList *ListNode) *RangeNode {
+ return &RangeNode{NodeType: NodeRange, Line: line, Pipe: pipe, List: list, ElseList: elseList}
+}
+
+func (r *RangeNode) String() string {
+ if r.ElseList != nil {
+ return fmt.Sprintf("({{range %s}} %s {{else}} %s)", r.Pipe, r.List, r.ElseList)
+ }
+ return fmt.Sprintf("({{range %s}} %s)", r.Pipe, r.List)
+}
+
+// TemplateNode represents a {{template}} action.
+type TemplateNode struct {
+ NodeType
+ Line int // The line number in the input.
+ Name string // The name of the template (unquoted).
+ Pipe *PipeNode // The command to evaluate as dot for the template.
+}
+
+func newTemplate(line int, name string, pipe *PipeNode) *TemplateNode {
+ return &TemplateNode{NodeType: NodeTemplate, Line: line, Name: name, Pipe: pipe}
+}
+
+func (t *TemplateNode) String() string {
+ if t.Pipe == nil {
+ return fmt.Sprintf("{{template %q}}", t.Name)
+ }
+ return fmt.Sprintf("{{template %q %s}}", t.Name, t.Pipe)
+}
+
+// WithNode represents a {{with}} action and its commands.
+type WithNode struct {
+ NodeType
+ Line int // The line number in the input.
+ Pipe *PipeNode // The pipeline to be evaluated.
+ List *ListNode // What to execute if the value is non-empty.
+ ElseList *ListNode // What to execute if the value is empty (nil if absent).
+}
+
+func newWith(line int, pipe *PipeNode, list, elseList *ListNode) *WithNode {
+ return &WithNode{NodeType: NodeWith, Line: line, Pipe: pipe, List: list, ElseList: elseList}
+}
+
+func (w *WithNode) String() string {
+ if w.ElseList != nil {
+ return fmt.Sprintf("({{with %s}} %s {{else}} %s)", w.Pipe, w.List, w.ElseList)
+ }
+ return fmt.Sprintf("({{with %s}} %s)", w.Pipe, w.List)
+}
diff --git a/src/pkg/template/parse/parse.go b/src/pkg/template/parse/parse.go
new file mode 100644
index 000000000..9a411a3f3
--- /dev/null
+++ b/src/pkg/template/parse/parse.go
@@ -0,0 +1,436 @@
+// 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 builds parse trees for templates. The grammar is defined
+// in the documents for the template package.
+package parse
+
+import (
+ "fmt"
+ "os"
+ "runtime"
+ "strconv"
+ "unicode"
+)
+
+// Tree is the representation of a parsed template.
+type Tree struct {
+ Name string // Name is the name of the template.
+ Root *ListNode // Root is the top-level root of the parse tree.
+ // Parsing only; cleared after parse.
+ funcs []map[string]interface{}
+ lex *lexer
+ token [2]item // two-token lookahead for parser.
+ peekCount int
+ vars []string // variables defined at the moment.
+}
+
+// next returns the next token.
+func (t *Tree) next() item {
+ if t.peekCount > 0 {
+ t.peekCount--
+ } else {
+ t.token[0] = t.lex.nextItem()
+ }
+ return t.token[t.peekCount]
+}
+
+// backup backs the input stream up one token.
+func (t *Tree) backup() {
+ t.peekCount++
+}
+
+// backup2 backs the input stream up two tokens
+func (t *Tree) backup2(t1 item) {
+ t.token[1] = t1
+ t.peekCount = 2
+}
+
+// peek returns but does not consume the next token.
+func (t *Tree) peek() item {
+ if t.peekCount > 0 {
+ return t.token[t.peekCount-1]
+ }
+ t.peekCount = 1
+ t.token[0] = t.lex.nextItem()
+ return t.token[0]
+}
+
+// Parsing.
+
+// New allocates a new template with the given name.
+func New(name string, funcs ...map[string]interface{}) *Tree {
+ return &Tree{
+ Name: name,
+ funcs: funcs,
+ }
+}
+
+// errorf formats the error and terminates processing.
+func (t *Tree) errorf(format string, args ...interface{}) {
+ t.Root = nil
+ format = fmt.Sprintf("template: %s:%d: %s", t.Name, t.lex.lineNumber(), format)
+ panic(fmt.Errorf(format, args...))
+}
+
+// error terminates processing.
+func (t *Tree) error(err os.Error) {
+ t.errorf("%s", err)
+}
+
+// expect consumes the next token and guarantees it has the required type.
+func (t *Tree) expect(expected itemType, context string) item {
+ token := t.next()
+ if token.typ != expected {
+ t.errorf("expected %s in %s; got %s", expected, context, token)
+ }
+ return token
+}
+
+// unexpected complains about the token and terminates processing.
+func (t *Tree) unexpected(token item, context string) {
+ t.errorf("unexpected %s in %s", token, context)
+}
+
+// recover is the handler that turns panics into returns from the top level of Parse.
+func (t *Tree) recover(errp *os.Error) {
+ e := recover()
+ if e != nil {
+ if _, ok := e.(runtime.Error); ok {
+ panic(e)
+ }
+ if t != nil {
+ t.stopParse()
+ }
+ *errp = e.(os.Error)
+ }
+ return
+}
+
+// startParse starts the template parsing from the lexer.
+func (t *Tree) startParse(funcs []map[string]interface{}, lex *lexer) {
+ t.Root = nil
+ t.lex = lex
+ t.vars = []string{"$"}
+ t.funcs = funcs
+}
+
+// stopParse terminates parsing.
+func (t *Tree) stopParse() {
+ t.lex = nil
+ t.vars = nil
+ t.funcs = nil
+}
+
+// atEOF returns true if, possibly after spaces, we're at EOF.
+func (t *Tree) atEOF() bool {
+ for {
+ token := t.peek()
+ switch token.typ {
+ case itemEOF:
+ return true
+ case itemText:
+ for _, r := range token.val {
+ if !unicode.IsSpace(r) {
+ return false
+ }
+ }
+ t.next() // skip spaces.
+ continue
+ }
+ break
+ }
+ return false
+}
+
+// Parse parses the template definition string to construct an internal
+// representation of the template for execution.
+func (t *Tree) Parse(s string, funcs ...map[string]interface{}) (tree *Tree, err os.Error) {
+ defer t.recover(&err)
+ t.startParse(funcs, lex(t.Name, s))
+ t.parse(true)
+ t.stopParse()
+ return t, nil
+}
+
+// parse is the helper for Parse.
+// It triggers an error if we expect EOF but don't reach it.
+func (t *Tree) parse(toEOF bool) (next Node) {
+ t.Root, next = t.itemList(true)
+ if toEOF && next != nil {
+ t.errorf("unexpected %s", next)
+ }
+ return next
+}
+
+// itemList:
+// textOrAction*
+// Terminates at EOF and at {{end}} or {{else}}, which is returned separately.
+// The toEOF flag tells whether we expect to reach EOF.
+func (t *Tree) itemList(toEOF bool) (list *ListNode, next Node) {
+ list = newList()
+ for t.peek().typ != itemEOF {
+ n := t.textOrAction()
+ switch n.Type() {
+ case NodeEnd, NodeElse:
+ return list, n
+ }
+ list.append(n)
+ }
+ if !toEOF {
+ t.unexpected(t.next(), "input")
+ }
+ return list, nil
+}
+
+// textOrAction:
+// text | action
+func (t *Tree) textOrAction() Node {
+ switch token := t.next(); token.typ {
+ case itemText:
+ return newText(token.val)
+ case itemLeftDelim:
+ return t.action()
+ default:
+ t.unexpected(token, "input")
+ }
+ return nil
+}
+
+// Action:
+// control
+// command ("|" command)*
+// Left delim is past. Now get actions.
+// First word could be a keyword such as range.
+func (t *Tree) action() (n Node) {
+ switch token := t.next(); token.typ {
+ case itemElse:
+ return t.elseControl()
+ case itemEnd:
+ return t.endControl()
+ case itemIf:
+ return t.ifControl()
+ case itemRange:
+ return t.rangeControl()
+ case itemTemplate:
+ return t.templateControl()
+ case itemWith:
+ return t.withControl()
+ }
+ t.backup()
+ // Do not pop variables; they persist until "end".
+ return newAction(t.lex.lineNumber(), t.pipeline("command"))
+}
+
+// Pipeline:
+// field or command
+// pipeline "|" pipeline
+func (t *Tree) pipeline(context string) (pipe *PipeNode) {
+ var decl []*VariableNode
+ // Are there declarations?
+ for {
+ if v := t.peek(); v.typ == itemVariable {
+ t.next()
+ if next := t.peek(); next.typ == itemColonEquals || next.typ == itemChar {
+ t.next()
+ variable := newVariable(v.val)
+ if len(variable.Ident) != 1 {
+ t.errorf("illegal variable in declaration: %s", v.val)
+ }
+ decl = append(decl, variable)
+ t.vars = append(t.vars, v.val)
+ if next.typ == itemChar && next.val == "," {
+ if context == "range" && len(decl) < 2 {
+ continue
+ }
+ t.errorf("too many declarations in %s", context)
+ }
+ } else {
+ t.backup2(v)
+ }
+ }
+ break
+ }
+ pipe = newPipeline(t.lex.lineNumber(), decl)
+ for {
+ switch token := t.next(); token.typ {
+ case itemRightDelim:
+ if len(pipe.Cmds) == 0 {
+ t.errorf("missing value for %s", context)
+ }
+ return
+ case itemBool, itemCharConstant, itemComplex, itemDot, itemField, itemIdentifier,
+ itemVariable, itemNumber, itemRawString, itemString:
+ t.backup()
+ pipe.append(t.command())
+ default:
+ t.unexpected(token, context)
+ }
+ }
+ return
+}
+
+func (t *Tree) parseControl(context string) (lineNum int, pipe *PipeNode, list, elseList *ListNode) {
+ lineNum = t.lex.lineNumber()
+ defer t.popVars(len(t.vars))
+ pipe = t.pipeline(context)
+ var next Node
+ list, next = t.itemList(false)
+ switch next.Type() {
+ case NodeEnd: //done
+ case NodeElse:
+ elseList, next = t.itemList(false)
+ if next.Type() != NodeEnd {
+ t.errorf("expected end; found %s", next)
+ }
+ elseList = elseList
+ }
+ return lineNum, pipe, list, elseList
+}
+
+// If:
+// {{if pipeline}} itemList {{end}}
+// {{if pipeline}} itemList {{else}} itemList {{end}}
+// If keyword is past.
+func (t *Tree) ifControl() Node {
+ return newIf(t.parseControl("if"))
+}
+
+// Range:
+// {{range pipeline}} itemList {{end}}
+// {{range pipeline}} itemList {{else}} itemList {{end}}
+// Range keyword is past.
+func (t *Tree) rangeControl() Node {
+ return newRange(t.parseControl("range"))
+}
+
+// With:
+// {{with pipeline}} itemList {{end}}
+// {{with pipeline}} itemList {{else}} itemList {{end}}
+// If keyword is past.
+func (t *Tree) withControl() Node {
+ return newWith(t.parseControl("with"))
+}
+
+// End:
+// {{end}}
+// End keyword is past.
+func (t *Tree) endControl() Node {
+ t.expect(itemRightDelim, "end")
+ return newEnd()
+}
+
+// Else:
+// {{else}}
+// Else keyword is past.
+func (t *Tree) elseControl() Node {
+ t.expect(itemRightDelim, "else")
+ return newElse(t.lex.lineNumber())
+}
+
+// Template:
+// {{template stringValue pipeline}}
+// Template keyword is past. The name must be something that can evaluate
+// to a string.
+func (t *Tree) templateControl() Node {
+ var name string
+ switch token := t.next(); token.typ {
+ case itemString, itemRawString:
+ s, err := strconv.Unquote(token.val)
+ if err != nil {
+ t.error(err)
+ }
+ name = s
+ default:
+ t.unexpected(token, "template invocation")
+ }
+ var pipe *PipeNode
+ if t.next().typ != itemRightDelim {
+ t.backup()
+ // Do not pop variables; they persist until "end".
+ pipe = t.pipeline("template")
+ }
+ return newTemplate(t.lex.lineNumber(), name, pipe)
+}
+
+// command:
+// space-separated arguments up to a pipeline character or right delimiter.
+// we consume the pipe character but leave the right delim to terminate the action.
+func (t *Tree) command() *CommandNode {
+ cmd := newCommand()
+Loop:
+ for {
+ switch token := t.next(); token.typ {
+ case itemRightDelim:
+ t.backup()
+ break Loop
+ case itemPipe:
+ break Loop
+ case itemError:
+ t.errorf("%s", token.val)
+ case itemIdentifier:
+ if !t.hasFunction(token.val) {
+ t.errorf("function %q not defined", token.val)
+ }
+ cmd.append(NewIdentifier(token.val))
+ case itemDot:
+ cmd.append(newDot())
+ case itemVariable:
+ cmd.append(t.useVar(token.val))
+ case itemField:
+ cmd.append(newField(token.val))
+ case itemBool:
+ cmd.append(newBool(token.val == "true"))
+ case itemCharConstant, itemComplex, itemNumber:
+ number, err := newNumber(token.val, token.typ)
+ if err != nil {
+ t.error(err)
+ }
+ cmd.append(number)
+ case itemString, itemRawString:
+ s, err := strconv.Unquote(token.val)
+ if err != nil {
+ t.error(err)
+ }
+ cmd.append(newString(token.val, s))
+ default:
+ t.unexpected(token, "command")
+ }
+ }
+ if len(cmd.Args) == 0 {
+ t.errorf("empty command")
+ }
+ return cmd
+}
+
+// hasFunction reports if a function name exists in the Tree's maps.
+func (t *Tree) hasFunction(name string) bool {
+ for _, funcMap := range t.funcs {
+ if funcMap == nil {
+ continue
+ }
+ if funcMap[name] != nil {
+ return true
+ }
+ }
+ return false
+}
+
+// popVars trims the variable list to the specified length
+func (t *Tree) popVars(n int) {
+ t.vars = t.vars[:n]
+}
+
+// useVar returns a node for a variable reference. It errors if the
+// variable is not defined.
+func (t *Tree) useVar(name string) Node {
+ v := newVariable(name)
+ for _, varName := range t.vars {
+ if varName == v.Ident[0] {
+ return v
+ }
+ }
+ t.errorf("undefined variable %q", v.Ident[0])
+ return nil
+}
diff --git a/src/pkg/template/parse/parse_test.go b/src/pkg/template/parse/parse_test.go
new file mode 100644
index 000000000..1928c319d
--- /dev/null
+++ b/src/pkg/template/parse/parse_test.go
@@ -0,0 +1,259 @@
+// 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"
+ "testing"
+)
+
+var debug = flag.Bool("debug", false, "show the errors produced by the 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(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
+}
+
+const (
+ noError = true
+ hasError = false
+)
+
+var parseTests = []parseTest{
+ {"empty", "", noError,
+ `[]`},
+ {"comment", "{{/*\n\n\n*/}}", noError,
+ `[]`},
+ {"spaces", " \t\n", noError,
+ `[(text: " \t\n")]`},
+ {"text", "some text", noError,
+ `[(text: "some text")]`},
+ {"emptyAction", "{{}}", hasError,
+ `[(action: [])]`},
+ {"field", "{{.X}}", noError,
+ `[(action: [(command: [F=[X]])])]`},
+ {"simple command", "{{printf}}", noError,
+ `[(action: [(command: [I=printf])])]`},
+ {"$ invocation", "{{$}}", noError,
+ "[(action: [(command: [V=[$]])])]"},
+ {"variable invocation", "{{with $x := 3}}{{$x 23}}{{end}}", noError,
+ "[({{with [V=[$x]] := [(command: [N=3])]}} [(action: [(command: [V=[$x] N=23])])])]"},
+ {"variable with fields", "{{$.I}}", noError,
+ "[(action: [(command: [V=[$ I]])])]"},
+ {"multi-word command", "{{printf `%d` 23}}", noError,
+ "[(action: [(command: [I=printf S=`%d` N=23])])]"},
+ {"pipeline", "{{.X|.Y}}", noError,
+ `[(action: [(command: [F=[X]]) (command: [F=[Y]])])]`},
+ {"pipeline with decl", "{{$x := .X|.Y}}", noError,
+ `[(action: [V=[$x]] := [(command: [F=[X]]) (command: [F=[Y]])])]`},
+ {"declaration", "{{.X|.Y}}", noError,
+ `[(action: [(command: [F=[X]]) (command: [F=[Y]])])]`},
+ {"simple if", "{{if .X}}hello{{end}}", noError,
+ `[({{if [(command: [F=[X]])]}} [(text: "hello")])]`},
+ {"if with else", "{{if .X}}true{{else}}false{{end}}", noError,
+ `[({{if [(command: [F=[X]])]}} [(text: "true")] {{else}} [(text: "false")])]`},
+ {"simple range", "{{range .X}}hello{{end}}", noError,
+ `[({{range [(command: [F=[X]])]}} [(text: "hello")])]`},
+ {"chained field range", "{{range .X.Y.Z}}hello{{end}}", noError,
+ `[({{range [(command: [F=[X Y Z]])]}} [(text: "hello")])]`},
+ {"nested range", "{{range .X}}hello{{range .Y}}goodbye{{end}}{{end}}", noError,
+ `[({{range [(command: [F=[X]])]}} [(text: "hello")({{range [(command: [F=[Y]])]}} [(text: "goodbye")])])]`},
+ {"range with else", "{{range .X}}true{{else}}false{{end}}", noError,
+ `[({{range [(command: [F=[X]])]}} [(text: "true")] {{else}} [(text: "false")])]`},
+ {"range over pipeline", "{{range .X|.M}}true{{else}}false{{end}}", noError,
+ `[({{range [(command: [F=[X]]) (command: [F=[M]])]}} [(text: "true")] {{else}} [(text: "false")])]`},
+ {"range []int", "{{range .SI}}{{.}}{{end}}", noError,
+ `[({{range [(command: [F=[SI]])]}} [(action: [(command: [{{<.>}}])])])]`},
+ {"constants", "{{range .SI 1 -3.2i true false 'a'}}{{end}}", noError,
+ `[({{range [(command: [F=[SI] N=1 N=-3.2i B=true B=false N='a'])]}} [])]`},
+ {"template", "{{template `x`}}", noError,
+ `[{{template "x"}}]`},
+ {"template with arg", "{{template `x` .Y}}", noError,
+ `[{{template "x" [(command: [F=[Y]])]}}]`},
+ {"with", "{{with .X}}hello{{end}}", noError,
+ `[({{with [(command: [F=[X]])]}} [(text: "hello")])]`},
+ {"with with else", "{{with .X}}hello{{else}}goodbye{{end}}", noError,
+ `[({{with [(command: [F=[X]])]}} [(text: "hello")] {{else}} [(text: "goodbye")])]`},
+ // 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, ""},
+}
+
+var builtins = map[string]interface{}{
+ "printf": fmt.Sprintf,
+}
+
+func TestParse(t *testing.T) {
+ for _, test := range parseTests {
+ tmpl, err := New(test.name).Parse(test.input, 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
+ }
+ 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)
+ }
+ }
+}
diff --git a/src/pkg/template/parse/set.go b/src/pkg/template/parse/set.go
new file mode 100644
index 000000000..4820da925
--- /dev/null
+++ b/src/pkg/template/parse/set.go
@@ -0,0 +1,50 @@
+// 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 (
+ "fmt"
+ "os"
+ "strconv"
+)
+
+// Set returns a slice of Trees created by parsing the template set
+// definition in the argument string. If an error is encountered,
+// parsing stops and an empty slice is returned with the error.
+func Set(text string, funcs ...map[string]interface{}) (tree map[string]*Tree, err os.Error) {
+ tree = make(map[string]*Tree)
+ defer (*Tree)(nil).recover(&err)
+ lex := lex("set", text)
+ const context = "define clause"
+ for {
+ t := New("set") // name will be updated once we know it.
+ t.startParse(funcs, lex)
+ // Expect EOF or "{{ define name }}".
+ if t.atEOF() {
+ break
+ }
+ t.expect(itemLeftDelim, context)
+ t.expect(itemDefine, context)
+ name := t.expect(itemString, context)
+ t.Name, err = strconv.Unquote(name.val)
+ if err != nil {
+ t.error(err)
+ }
+ t.expect(itemRightDelim, context)
+ end := t.parse(false)
+ if end == nil {
+ t.errorf("unexpected EOF in %s", context)
+ }
+ if end.Type() != NodeEnd {
+ t.errorf("unexpected %s in %s", end, context)
+ }
+ t.stopParse()
+ if _, present := tree[t.Name]; present {
+ return nil, fmt.Errorf("template: %q multiply defined", name)
+ }
+ tree[t.Name] = t
+ }
+ return
+}
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-30 15:27:38 +0000