exp/template: add template sets, allowing templates to reference one another
R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4673042
diff --git a/src/pkg/exp/template/Makefile b/src/pkg/exp/template/Makefile
index a2d39e2..50a0bd7 100644
--- a/src/pkg/exp/template/Makefile
+++ b/src/pkg/exp/template/Makefile
@@ -9,5 +9,6 @@
exec.go\
lex.go\
parse.go\
+ set.go\
include ../../../Make.pkg
diff --git a/src/pkg/exp/template/exec.go b/src/pkg/exp/template/exec.go
index 27c1b09..3eaecd1 100644
--- a/src/pkg/exp/template/exec.go
+++ b/src/pkg/exp/template/exec.go
@@ -9,6 +9,7 @@
"io"
"os"
"reflect"
+ "strings"
)
// state represents the state of an execution. It's not part of the
@@ -17,6 +18,7 @@
type state struct {
tmpl *Template
wr io.Writer
+ set *Set
line int // line number for errors
}
@@ -33,11 +35,19 @@
// Execute applies a parsed template to the specified data object,
// writing the output to wr.
-func (t *Template) Execute(wr io.Writer, data interface{}) (err os.Error) {
+func (t *Template) Execute(wr io.Writer, data interface{}) os.Error {
+ return t.ExecuteInSet(wr, data, nil)
+}
+
+// ExecuteInSet applies a parsed template to the specified data object,
+// writing the output to wr. Nested template invocations will be resolved
+// from the specified set.
+func (t *Template) ExecuteInSet(wr io.Writer, data interface{}, set *Set) (err os.Error) {
defer t.recover(&err)
state := &state{
tmpl: t,
wr: wr,
+ set: set,
line: 1,
}
if t.root == nil {
@@ -49,7 +59,6 @@
// Walk functions step through the major pieces of the template structure,
// generating output as they go.
-
func (s *state) walk(data reflect.Value, n node) {
switch n := n.(type) {
case *actionNode:
@@ -59,17 +68,56 @@
for _, node := range n.nodes {
s.walk(data, node)
}
+ case *ifNode:
+ s.walkIfOrWith(nodeIf, data, n.pipeline, n.list, n.elseList)
case *rangeNode:
s.walkRange(data, n)
case *textNode:
if _, err := s.wr.Write(n.text); err != nil {
s.error(err)
}
+ case *templateNode:
+ s.walkTemplate(data, n)
+ case *withNode:
+ s.walkIfOrWith(nodeWith, data, n.pipeline, n.list, n.elseList)
default:
s.errorf("unknown node: %s", n)
}
}
+// walkIfOrWith walks an 'if' or 'with' node. The two control structures
+// are identical in behavior except that 'with' sets dot.
+func (s *state) walkIfOrWith(typ nodeType, data reflect.Value, pipe []*commandNode, list, elseList *listNode) {
+ val := s.evalPipeline(data, pipe)
+ truth := false
+ switch val.Kind() {
+ case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+ truth = val.Len() > 0
+ case reflect.Bool:
+ truth = val.Bool()
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ truth = val.Int() != 0
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ truth = val.Uint() != 0
+ case reflect.Float32, reflect.Float64:
+ truth = val.Float() != 0
+ case reflect.Complex64, reflect.Complex128:
+ truth = val.Complex() != 0
+ case reflect.Chan, reflect.Func, reflect.Ptr:
+ truth = !val.IsNil()
+ default:
+ s.errorf("if/with can't use value of type %T", val.Interface())
+ }
+ if truth {
+ if typ == nodeWith {
+ data = val
+ }
+ s.walk(data, list)
+ } else if elseList != nil {
+ s.walk(data, elseList)
+ }
+}
+
func (s *state) walkRange(data reflect.Value, r *rangeNode) {
val := s.evalPipeline(data, r.pipeline)
switch val.Kind() {
@@ -97,6 +145,21 @@
}
}
+func (s *state) walkTemplate(data reflect.Value, t *templateNode) {
+ name := s.evalArg(data, reflect.TypeOf("string"), t.name).String()
+ if s.set == nil {
+ s.errorf("no set defined in which to invoke template named %q", name)
+ }
+ tmpl := s.set.tmpl[name]
+ if tmpl == nil {
+ s.errorf("template %q not in set", name)
+ }
+ data = s.evalPipeline(data, t.pipeline)
+ newState := *s
+ newState.tmpl = tmpl
+ newState.walk(data, tmpl.root)
+}
+
// Eval functions evaluate pipelines, commands, and their elements and extract
// values from the data structure by examining fields, calling methods, and so on.
// The printing of those values happens only through walk functions.
@@ -110,16 +173,38 @@
}
func (s *state) evalCommand(data reflect.Value, cmd *commandNode, final reflect.Value) reflect.Value {
- switch field := cmd.args[0].(type) {
- case *dotNode:
- if final.IsValid() {
- s.errorf("can't give argument to dot")
- }
- return data
- case *fieldNode:
+ firstWord := cmd.args[0]
+ if field, ok := firstWord.(*fieldNode); ok {
return s.evalFieldNode(data, field, cmd.args, final)
}
- s.errorf("%s not a field", cmd.args[0])
+ if len(cmd.args) > 1 || final.IsValid() {
+ // TODO: functions
+ s.errorf("can't give argument to non-method %s", cmd.args[0])
+ }
+ switch word := cmd.args[0].(type) {
+ case *dotNode:
+ return data
+ case *boolNode:
+ return reflect.ValueOf(word.true)
+ case *numberNode:
+ // These are ideal constants but we don't know the type
+ // and we have no context. (If it was a method argument,
+ // we'd know what we need.) The syntax guides us to some extent.
+ switch {
+ case word.isComplex:
+ return reflect.ValueOf(word.complex128) // incontrovertible.
+ case word.isFloat && strings.IndexAny(word.text, ".eE") >= 0:
+ return reflect.ValueOf(word.float64)
+ case word.isInt:
+ return reflect.ValueOf(word.int64)
+ case word.isUint:
+ return reflect.ValueOf(word.uint64)
+ }
+ case *stringNode:
+ return reflect.ValueOf(word.text)
+ default:
+ s.errorf("can't handle command %q", firstWord)
+ }
panic("not reached")
}
@@ -148,7 +233,7 @@
}
s.errorf("%s has no field %s", data.Type(), fieldName)
default:
- s.errorf("can't evaluate field %s of type %s", fieldName, data.Type())
+ s.errorf("can't evaluate field %s of type %s", fieldName, data.Type())
}
panic("not reached")
}
@@ -282,7 +367,7 @@
}
func (s *state) evalFloat(v reflect.Value, typ reflect.Type, n node) reflect.Value {
- if n, ok := n.(*numberNode); ok && n.isFloat && !n.imaginary {
+ if n, ok := n.(*numberNode); ok && n.isFloat {
value := reflect.New(typ).Elem()
value.SetFloat(n.float64)
return value
@@ -292,9 +377,9 @@
}
func (s *state) evalComplex(v reflect.Value, typ reflect.Type, n node) reflect.Value {
- if n, ok := n.(*numberNode); ok && n.isFloat && n.imaginary {
+ if n, ok := n.(*numberNode); ok && n.isComplex {
value := reflect.New(typ).Elem()
- value.SetComplex(complex(0, n.float64))
+ value.SetComplex(n.complex128)
return value
}
s.errorf("expected complex; found %s", n)
diff --git a/src/pkg/exp/template/exec_test.go b/src/pkg/exp/template/exec_test.go
index bd21125..6e4da69 100644
--- a/src/pkg/exp/template/exec_test.go
+++ b/src/pkg/exp/template/exec_test.go
@@ -16,17 +16,20 @@
// T has lots of interesting pieces to use to test execution.
type T struct {
// Basics
- I int
- U16 uint16
- X string
+ I int
+ U16 uint16
+ X string
+ FloatZero float64
+ ComplexZero float64
// Nested structs.
U *U
// Slices
- SI []int
- SEmpty []int
- SB []bool
+ SI []int
+ SIEmpty []int
+ SB []bool
// Maps
MSI map[string]int
+ MSIone map[string]int // one element, for deterministic output
MSIEmpty map[string]int
}
@@ -76,13 +79,14 @@
}
var tVal = &T{
- I: 17,
- U16: 16,
- X: "x",
- U: &U{"v"},
- SI: []int{3, 4, 5},
- SB: []bool{true, false},
- MSI: map[string]int{"one": 1, "two": 2, "three": 3},
+ I: 17,
+ U16: 16,
+ X: "x",
+ U: &U{"v"},
+ SI: []int{3, 4, 5},
+ SB: []bool{true, false},
+ MSI: map[string]int{"one": 1, "two": 2, "three": 3},
+ MSIone: map[string]int{"one": 1},
}
type execTest struct {
@@ -94,31 +98,80 @@
}
var execTests = []execTest{
+ // Trivial cases.
{"empty", "", "", nil, true},
{"text", "some text", "some text", nil, true},
+ // Fields of structs.
{".X", "-{{.X}}-", "-x-", tVal, true},
{".U.V", "-{{.U.V}}-", "-v-", tVal, true},
+ // Dots of all kinds to test basic evaluation.
+ {"dot int", "<{{.}}>", "<13>", 13, true},
+ {"dot uint", "<{{.}}>", "<14>", uint(14), true},
+ {"dot float", "<{{.}}>", "<15.1>", 15.1, true},
+ {"dot bool", "<{{.}}>", "<true>", true, true},
+ {"dot complex", "<{{.}}>", "<(16.2-17i)>", 16.2 - 17i, true},
+ {"dot string", "<{{.}}>", "<hello>", "hello", true},
+ {"dot slice", "<{{.}}>", "<[-1 -2 -3]>", []int{-1, -2, -3}, true},
+ {"dot map", "<{{.}}>", "<map[two:22 one:11]>", map[string]int{"one": 11, "two": 22}, true},
+ {"dot struct", "<{{.}}>", "<{7 seven}>", struct {
+ a int
+ b string
+ }{7, "seven"}, true},
+ // Method calls.
{".Method0", "-{{.Method0}}-", "-resultOfMethod0-", tVal, true},
{".Method1(1234)", "-{{.Method1 1234}}-", "-1234-", tVal, true},
{".Method1(.I)", "-{{.Method1 .I}}-", "-17-", tVal, true},
{".Method2(3, .X)", "-{{.Method2 3 .X}}-", "-Method2: 3 x-", tVal, true},
{".Method2(.U16, `str`)", "-{{.Method2 .U16 `str`}}-", "-Method2: 16 str-", tVal, true},
+ // Pipelines.
{"pipeline", "-{{.Method0 | .Method2 .U16}}-", "-Method2: 16 resultOfMethod0-", tVal, true},
+ // If.
+ {"if true", "{{if true}}TRUE{{end}}", "TRUE", tVal, true},
+ {"if false", "{{if false}}TRUE{{else}}FALSE{{end}}", "FALSE", tVal, true},
+ {"if 1", "{{if 1}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true},
+ {"if 0", "{{if 0}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true},
+ {"if 1.5", "{{if 1.5}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true},
+ {"if 0.0", "{{if .FloatZero}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true},
+ {"if 1.5i", "{{if 1.5i}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true},
+ {"if 0.0i", "{{if .ComplexZero}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true},
+ {"if emptystring", "{{if ``}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ {"if string", "{{if `notempty`}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true},
+ {"if emptyslice", "{{if .SIEmpty}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ {"if slice", "{{if .SI}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true},
+ {"if emptymap", "{{if .MSIEmpty}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ {"if map", "{{if .MSI}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true},
+ // With.
+ {"with true", "{{with true}}{{.}}{{end}}", "true", tVal, true},
+ {"with false", "{{with false}}{{.}}{{else}}FALSE{{end}}", "FALSE", tVal, true},
+ {"with 1", "{{with 1}}{{.}}{{else}}ZERO{{end}}", "1", tVal, true},
+ {"with 0", "{{with 0}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true},
+ {"with 1.5", "{{with 1.5}}{{.}}{{else}}ZERO{{end}}", "1.5", tVal, true},
+ {"with 0.0", "{{with .FloatZero}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true},
+ {"with 1.5i", "{{with 1.5i}}{{.}}{{else}}ZERO{{end}}", "(0+1.5i)", tVal, true},
+ {"with 0.0i", "{{with .ComplexZero}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true},
+ {"with emptystring", "{{with ``}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ {"with string", "{{with `notempty`}}{{.}}{{else}}EMPTY{{end}}", "notempty", tVal, true},
+ {"with emptyslice", "{{with .SIEmpty}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ {"with slice", "{{with .SI}}{{.}}{{else}}EMPTY{{end}}", "[3 4 5]", tVal, true},
+ {"with emptymap", "{{with .MSIEmpty}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ {"with map", "{{with .MSIone}}{{.}}{{else}}EMPTY{{end}}", "map[one:1]", tVal, true},
+ // Range.
{"range []int", "{{range .SI}}-{{.}}-{{end}}", "-3--4--5-", tVal, true},
- {"range empty no else", "{{range .SEmpty}}-{{.}}-{{end}}", "", tVal, true},
+ {"range empty no else", "{{range .SIEmpty}}-{{.}}-{{end}}", "", tVal, true},
{"range []int else", "{{range .SI}}-{{.}}-{{else}}EMPTY{{end}}", "-3--4--5-", tVal, true},
- {"range empty else", "{{range .SEmpty}}-{{.}}-{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ {"range empty else", "{{range .SIEmpty}}-{{.}}-{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
{"range []bool", "{{range .SB}}-{{.}}-{{end}}", "-true--false-", tVal, true},
{"range []int method", "{{range .SI | .MAdd .I}}-{{.}}-{{end}}", "-20--21--22-", tVal, true},
{"range map", "{{range .MSI | .MSort}}-{{.}}-{{end}}", "-one--three--two-", tVal, true},
{"range empty map no else", "{{range .MSIEmpty}}-{{.}}-{{end}}", "", tVal, true},
{"range map else", "{{range .MSI | .MSort}}-{{.}}-{{else}}EMPTY{{end}}", "-one--three--two-", tVal, true},
{"range empty map else", "{{range .MSIEmpty}}-{{.}}-{{else}}EMPTY{{end}}", "EMPTY", tVal, true},
+ // Error handling.
{"error method, error", "{{.EPERM true}}", "", tVal, false},
{"error method, no error", "{{.EPERM false}}", "false", tVal, true},
}
-func TestExecute(t *testing.T) {
+func testExecute(execTests []execTest, set *Set, t *testing.T) {
b := new(bytes.Buffer)
for _, test := range execTests {
tmpl := New(test.name)
@@ -128,7 +181,7 @@
continue
}
b.Reset()
- err = tmpl.Execute(b, test.data)
+ err = tmpl.ExecuteInSet(b, test.data, set)
switch {
case !test.ok && err == nil:
t.Errorf("%s: expected error; got none", test.name)
@@ -146,6 +199,10 @@
}
}
+func TestExecute(t *testing.T) {
+ testExecute(execTests, nil, t)
+}
+
// Check that an error from a method flows back to the top.
func TestExecuteError(t *testing.T) {
b := new(bytes.Buffer)
diff --git a/src/pkg/exp/template/parse.go b/src/pkg/exp/template/parse.go
index f169555..74b5f2c 100644
--- a/src/pkg/exp/template/parse.go
+++ b/src/pkg/exp/template/parse.go
@@ -11,6 +11,7 @@
"runtime"
"strconv"
"strings"
+ "unicode"
)
// Template is the representation of a parsed template.
@@ -19,7 +20,7 @@
root *listNode
// Parsing.
lex *lexer
- tokens chan item
+ tokens <-chan item
token item // token lookahead for parser
havePeek bool
}
@@ -70,10 +71,13 @@
nodeEnd
nodeField
nodeIdentifier
+ nodeIf
nodeList
nodeNumber
nodeRange
nodeString
+ nodeTemplate
+ nodeWith
)
// Nodes.
@@ -215,31 +219,40 @@
return fmt.Sprintf("B=false")
}
-// numberNode holds a number, signed or unsigned, integer, floating, or imaginary.
+// numberNode holds a number, signed or unsigned integer, floating, 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.
-// TODO: booleans, complex numbers.
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
- imaginary bool // number is imaginary
- int64 // the signed integer value
- uint64 // the unsigned integer value
- float64 // the positive floating-point value
- text string
+ 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 // the signed integer value
+ uint64 // the unsigned integer value
+ float64 // the floating-point value
+ complex128 // the complex value
+ text string
}
-func newNumber(text string) (*numberNode, os.Error) {
+func newNumber(text string, isComplex bool) (*numberNode, os.Error) {
n := &numberNode{nodeType: nodeNumber, text: text}
- // Imaginary constants can only be floating-point.
+ if isComplex {
+ // 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.imaginary = true
- n.isFloat = true
- n.float64 = f
+ n.isComplex = true
+ n.complex128 = complex(0, f)
+ n.simplifyComplex()
return n, nil
}
}
@@ -287,6 +300,23 @@
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)
}
@@ -337,6 +367,26 @@
func (e *elseNode) String() string {
return "{{else}}"
}
+// ifNode represents an {{if}} action and its commands.
+// TODO: what should evaluation look like? is a pipeline enough?
+type ifNode struct {
+ nodeType
+ line int
+ pipeline []*commandNode
+ list *listNode
+ elseList *listNode
+}
+
+func newIf(line int, pipeline []*commandNode, list, elseList *listNode) *ifNode {
+ return &ifNode{nodeType: nodeIf, line: line, pipeline: pipeline, list: list, elseList: elseList}
+}
+
+func (i *ifNode) String() string {
+ if i.elseList != nil {
+ return fmt.Sprintf("({{if %s}} %s {{else}} %s)", i.pipeline, i.list, i.elseList)
+ }
+ return fmt.Sprintf("({{if %s}} %s)", i.pipeline, i.list)
+}
// rangeNode represents a {{range}} action and its commands.
type rangeNode struct {
@@ -347,8 +397,8 @@
elseList *listNode
}
-func newRange(line int, pipeline []*commandNode, list *listNode) *rangeNode {
- return &rangeNode{nodeType: nodeRange, line: line, pipeline: pipeline, list: list}
+func newRange(line int, pipeline []*commandNode, list, elseList *listNode) *rangeNode {
+ return &rangeNode{nodeType: nodeRange, line: line, pipeline: pipeline, list: list, elseList: elseList}
}
func (r *rangeNode) String() string {
@@ -358,6 +408,43 @@
return fmt.Sprintf("({{range %s}} %s)", r.pipeline, r.list)
}
+// templateNode represents a {{template}} action.
+type templateNode struct {
+ nodeType
+ line int
+ name node
+ pipeline []*commandNode
+}
+
+func newTemplate(line int, name node, pipeline []*commandNode) *templateNode {
+ return &templateNode{nodeType: nodeTemplate, line: line, name: name, pipeline: pipeline}
+}
+
+func (t *templateNode) String() string {
+ return fmt.Sprintf("{{template %s %s}}", t.name, t.pipeline)
+}
+
+// withNode represents a {{with}} action and its commands.
+type withNode struct {
+ nodeType
+ line int
+ pipeline []*commandNode
+ list *listNode
+ elseList *listNode
+}
+
+func newWith(line int, pipeline []*commandNode, list, elseList *listNode) *withNode {
+ return &withNode{nodeType: nodeWith, line: line, pipeline: pipeline, list: list, elseList: elseList}
+}
+
+func (w *withNode) String() string {
+ if w.elseList != nil {
+ return fmt.Sprintf("({{with %s}} %s {{else}} %s)", w.pipeline, w.list, w.elseList)
+ }
+ return fmt.Sprintf("({{with %s}} %s)", w.pipeline, w.list)
+}
+
+
// Parsing.
// New allocates a new template with the given name.
@@ -400,24 +487,62 @@
if _, ok := e.(runtime.Error); ok {
panic(e)
}
- t.root, t.lex, t.tokens = nil, nil, nil
+ t.stopParse()
+ t.root = nil
*errp = e.(os.Error)
}
return
}
+// startParse starts the template parsing from the lexer.
+func (t *Template) startParse(lex *lexer, tokens <-chan item) {
+ t.root = nil
+ t.lex, t.tokens = lex, tokens
+}
+
+// stopParse terminates parsing.
+func (t *Template) stopParse() {
+ t.lex, t.tokens = nil, nil
+}
+
+// atEOF returns true if, possibly after spaces, we're at EOF.
+func (t *Template) 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 *Template) Parse(s string) (err os.Error) {
- t.lex, t.tokens = lex(t.name, s)
+ t.startParse(lex(t.name, s))
defer t.recover(&err)
- var next node
+ t.parse(true)
+ t.stopParse()
+ return
+}
+
+// parse is the helper for Parse. It triggers an error if we expect EOF but don't reach it.
+func (t *Template) parse(toEOF bool) (next node) {
t.root, next = t.itemList(true)
- if next != nil {
+ if toEOF && next != nil {
t.errorf("unexpected %s", next)
}
- t.lex, t.tokens = nil, nil
- return nil
+ return next
}
// itemList:
@@ -461,12 +586,18 @@
// First word could be a keyword such as range.
func (t *Template) action() (n node) {
switch token := t.next(); token.typ {
- case itemRange:
- return t.rangeControl()
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()
return newAction(t.lex.lineNumber(), t.pipeline("command"))
@@ -479,14 +610,13 @@
for {
switch token := t.next(); token.typ {
case itemRightMeta:
- return
- case itemIdentifier, itemField, itemDot:
- t.backup()
- cmd, err := t.command()
- if err != nil {
- t.error(err)
+ if len(pipe) == 0 {
+ t.errorf("missing value for %s", context)
}
- pipe = append(pipe, cmd)
+ return
+ case itemBool, itemComplex, itemDot, itemField, itemIdentifier, itemNumber, itemRawString, itemString:
+ t.backup()
+ pipe = append(pipe, t.command())
default:
t.unexpected(token, context)
}
@@ -494,26 +624,47 @@
return
}
-// Range:
-// {{range field}} itemList {{end}}
-// {{range field}} itemList {{else}} itemList {{end}}
-// Range keyword is past.
-func (t *Template) rangeControl() node {
- pipeline := t.pipeline("range")
- list, next := t.itemList(false)
- r := newRange(t.lex.lineNumber(), pipeline, list)
+func (t *Template) parseControl(context string) (lineNum int, pipe []*commandNode, list, elseList *listNode) {
+ pipe = t.pipeline(context)
+ var next node
+ list, next = t.itemList(false)
switch next.typ() {
case nodeEnd: //done
case nodeElse:
- elseList, next := t.itemList(false)
+ elseList, next = t.itemList(false)
if next.typ() != nodeEnd {
t.errorf("expected end; found %s", next)
}
- r.elseList = elseList
+ elseList = elseList
}
- return r
+ return lineNum, pipe, list, elseList
}
+// If:
+// {{if pipeline}} itemList {{end}}
+// {{if pipeline}} itemList {{else}} itemList {{end}}
+// If keyword is past.
+func (t *Template) ifControl() node {
+ return newIf(t.parseControl("if"))
+}
+
+// Range:
+// {{range pipeline}} itemList {{end}}
+// {{range pipeline}} itemList {{else}} itemList {{end}}
+// Range keyword is past.
+func (t *Template) rangeControl() node {
+ return newRange(t.parseControl("range"))
+}
+
+// With:
+// {{with pipeline}} itemList {{end}}
+// {{with pipeline}} itemList {{else}} itemList {{end}}
+// If keyword is past.
+func (t *Template) withControl() node {
+ return newWith(t.parseControl("with"))
+}
+
+
// End:
// {{end}}
// End keyword is past.
@@ -530,10 +681,36 @@
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 *Template) templateControl() node {
+ var name node
+ switch token := t.next(); token.typ {
+ case itemIdentifier:
+ name = newIdentifier(token.val)
+ case itemDot:
+ name = newDot()
+ case itemField:
+ name = newField(token.val)
+ case itemString, itemRawString:
+ s, err := strconv.Unquote(token.val)
+ if err != nil {
+ t.error(err)
+ }
+ name = newString(s)
+ default:
+ t.unexpected(token, "template invocation")
+ }
+ pipeline := t.pipeline("template")
+ return newTemplate(t.lex.lineNumber(), name, pipeline)
+}
+
// command:
// space-separated arguments up to a pipeline character or right metacharacter.
// we consume the pipe character but leave the right meta to terminate the action.
-func (t *Template) command() (*commandNode, os.Error) {
+func (t *Template) command() *commandNode {
cmd := newCommand()
Loop:
for {
@@ -544,7 +721,7 @@
case itemPipe:
break Loop
case itemError:
- return nil, os.NewError(token.val)
+ t.errorf("%s", token.val)
case itemIdentifier:
cmd.append(newIdentifier(token.val))
case itemDot:
@@ -553,22 +730,16 @@
cmd.append(newField(token.val))
case itemBool:
cmd.append(newBool(token.val == "true"))
- case itemNumber:
- if len(cmd.args) == 0 {
- t.errorf("command cannot be %q", token.val)
- }
- number, err := newNumber(token.val)
+ case itemComplex, itemNumber:
+ number, err := newNumber(token.val, token.typ == itemComplex)
if err != nil {
t.error(err)
}
cmd.append(number)
case itemString, itemRawString:
- if len(cmd.args) == 0 {
- t.errorf("command cannot be %q", token.val)
- }
s, err := strconv.Unquote(token.val)
if err != nil {
- return nil, err
+ t.error(err)
}
cmd.append(newString(s))
default:
@@ -578,5 +749,5 @@
if len(cmd.args) == 0 {
t.errorf("empty command")
}
- return cmd, nil
+ return cmd
}
diff --git a/src/pkg/exp/template/parse_test.go b/src/pkg/exp/template/parse_test.go
index b1da989..5c780cd2 100644
--- a/src/pkg/exp/template/parse_test.go
+++ b/src/pkg/exp/template/parse_test.go
@@ -16,41 +16,53 @@
isInt bool
isUint bool
isFloat bool
- imaginary bool
+ isComplex bool
int64
uint64
float64
+ complex128
}
var numberTests = []numberTest{
// basics
- {"0", true, true, true, false, 0, 0, 0},
- {"-0", true, true, true, false, 0, 0, 0}, // check that -0 is a uint.
- {"73", true, true, true, false, 73, 73, 73},
- {"-73", true, false, true, false, -73, 0, -73},
- {"+73", true, false, true, false, 73, 0, 73},
- {"100", true, true, true, false, 100, 100, 100},
- {"1e9", true, true, true, false, 1e9, 1e9, 1e9},
- {"-1e9", true, false, true, false, -1e9, 0, -1e9},
- {"-1.2", false, false, true, false, 0, 0, -1.2},
- {"1e19", false, true, true, false, 0, 1e19, 1e19},
- {"-1e19", false, false, true, false, 0, 0, -1e19},
- {"4i", false, false, true, true, 0, 0, 4},
+ {"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},
+ {"-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},
+ // 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},
- {"-0x0", true, true, true, false, 0, 0, 0},
- {"0xdeadbeef", true, true, true, false, 0xdeadbeef, 0xdeadbeef, 0xdeadbeef},
+ {"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},
// some broken syntax
{text: "+-2"},
{text: "0x123."},
{text: "1e."},
{text: "0xi."},
+ {text: "1+2."},
}
func TestNumberParse(t *testing.T) {
for _, test := range numberTests {
- n, err := newNumber(test.text)
- ok := test.isInt || test.isUint || test.isFloat
+ // 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
+ _, err := fmt.Sscan(test.text, &c)
+ n, err := newNumber(test.text, err == nil)
+ ok := test.isInt || test.isUint || test.isFloat || test.isComplex
if ok && err != nil {
t.Errorf("unexpected error for %q", test.text)
continue
@@ -62,8 +74,8 @@
if !ok {
continue
}
- if n.imaginary != test.imaginary {
- t.Errorf("imaginary incorrect for %q; should be %t", test.text, test.imaginary)
+ if n.isComplex != test.isComplex {
+ t.Errorf("complex incorrect for %q; should be %t", test.text, test.isComplex)
}
if test.isInt {
if !n.isInt {
@@ -95,17 +107,19 @@
} 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)
+ }
}
}
-func num(s string) *numberNode {
- n, err := newNumber(s)
- if err != nil {
- panic(err)
- }
- return n
-}
-
type parseTest struct {
name string
input string
@@ -125,7 +139,7 @@
`[(text: " \t\n")]`},
{"text", "some text", noError,
`[(text: "some text")]`},
- {"emptyMeta", "{{}}", noError,
+ {"emptyMeta", "{{}}", hasError,
`[(action: [])]`},
{"field", "{{.X}}", noError,
`[(action: [(command: [F=[X]])])]`},
@@ -139,6 +153,10 @@
"[(action: [(command: [I=hello S=`quoted text`])])]"},
{"pipeline", "{{hello|world}}", noError,
`[(action: [(command: [I=hello]) (command: [I=world])])]`},
+ {"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,
@@ -153,6 +171,12 @@
`[({{range [(command: [F=[SI]])]}} [(action: [(command: [{{<.>}}])])])]`},
{"constants", "{{range .SI 1 -3.2i true false }}{{end}}", noError,
`[({{range [(command: [F=[SI] N=1 N=-3.2i B=true B=false])]}} [])]`},
+ {"template", "{{template foo .X}}", noError,
+ "[{{template I=foo [(command: [F=[X]])]}}]"},
+ {"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, ""},
{"missing end", "hello{{range .x}}", hasError, ""},
diff --git a/src/pkg/exp/template/set.go b/src/pkg/exp/template/set.go
new file mode 100644
index 0000000..13d93d0
--- /dev/null
+++ b/src/pkg/exp/template/set.go
@@ -0,0 +1,71 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+ "os"
+ "runtime"
+ "strconv"
+)
+
+// Set holds a set of related templates that can refer to one another by name.
+// A template may be a member of multiple sets.
+type Set struct {
+ tmpl map[string]*Template
+}
+
+// NewSet allocates a new, empty template set.
+func NewSet() *Set {
+ return &Set{
+ tmpl: make(map[string]*Template),
+ }
+}
+
+// recover is the handler that turns panics into returns from the top
+// level of Parse.
+func (s *Set) recover(errp *os.Error) {
+ e := recover()
+ if e != nil {
+ if _, ok := e.(runtime.Error); ok {
+ panic(e)
+ }
+ s.tmpl = nil
+ *errp = e.(os.Error)
+ }
+ return
+}
+
+// Parse parses the file into a set of named templates.
+func (s *Set) Parse(text string) (err os.Error) {
+ defer s.recover(&err)
+ lex, tokens := lex("set", text)
+ const context = "define clause"
+ for {
+ t := New("set") // name will be updated once we know it.
+ t.startParse(lex, tokens)
+ // Expect EOF or "{{ define name }}".
+ if t.atEOF() {
+ return
+ }
+ t.expect(itemLeftMeta, 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(itemRightMeta, context)
+ end := t.parse(false)
+ if end == nil {
+ t.errorf("unexpected EOF in %s", context)
+ }
+ if end.typ() != nodeEnd {
+ t.errorf("unexpected %s in %s", end, context)
+ }
+ t.stopParse()
+ s.tmpl[t.name] = t
+ }
+ return nil
+}
diff --git a/src/pkg/exp/template/set_test.go b/src/pkg/exp/template/set_test.go
new file mode 100644
index 0000000..873d261
--- /dev/null
+++ b/src/pkg/exp/template/set_test.go
@@ -0,0 +1,101 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+ "fmt"
+ "testing"
+)
+
+type setParseTest struct {
+ name string
+ input string
+ ok bool
+ names []string
+ results []string
+}
+
+var setParseTests = []setParseTest{
+ {"empty", "", noError,
+ nil,
+ nil},
+ {"one", `{{define "foo"}} FOO {{end}}`, noError,
+ []string{"foo"},
+ []string{`[(text: " FOO ")]`}},
+ {"two", `{{define "foo"}} FOO {{end}}{{define "bar"}} BAR {{end}}`, noError,
+ []string{"foo", "bar"},
+ []string{`[(text: " FOO ")]`, `[(text: " BAR ")]`}},
+ // errors
+ {"missing end", `{{define "foo"}} FOO `, hasError,
+ nil,
+ nil},
+ {"malformed name", `{{define "foo}} FOO `, hasError,
+ nil,
+ nil},
+}
+
+func TestSetParse(t *testing.T) {
+ for _, test := range setParseTests {
+ set := NewSet()
+ err := set.Parse(test.input)
+ 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 dumpErrors {
+ fmt.Printf("%s: %s\n\t%s\n", test.name, test.input, err)
+ }
+ continue
+ }
+ if len(set.tmpl) != len(test.names) {
+ t.Errorf("%s: wrong number of templates; wanted %d got %d", test.name, len(test.names), len(set.tmpl))
+ continue
+ }
+ for i, name := range test.names {
+ tmpl, ok := set.tmpl[name]
+ if !ok {
+ t.Errorf("%s: can't find template %q", test.name, name)
+ continue
+ }
+ result := tmpl.root.String()
+ if result != test.results[i] {
+ t.Errorf("%s=(%q): got\n\t%v\nexpected\n\t%v", test.name, test.input, result, test.results[i])
+ }
+ }
+ }
+}
+
+
+var setExecTests = []execTest{
+ {"empty", "", "", nil, true},
+ {"text", "some text", "some text", nil, true},
+ {"invoke text", `{{template "text" .SI}}`, "TEXT", tVal, true},
+ {"invoke dot int", `{{template "dot" .I}}`, "17", tVal, true},
+ {"invoke dot []int", `{{template "dot" .SI}}`, "[3 4 5]", tVal, true},
+ {"invoke dotV", `{{template "dotV" .U}}`, "v", tVal, true},
+ {"invoke nested int", `{{template "nested" .I}}`, "17", tVal, true},
+}
+
+const setText = `
+ {{define "text"}}TEXT{{end}}
+ {{define "dotV"}}{{.V}}{{end}}
+ {{define "dot"}}{{.}}{{end}}
+ {{define "nested"}}{{template "dot" .}}{{end}}
+`
+
+func TestSetExecute(t *testing.T) {
+ // Declare a set with a couple of templates first.
+ set := NewSet()
+ err := set.Parse(setText)
+ if err != nil {
+ t.Fatalf("error parsing set: %s", err)
+ }
+ testExecute(setExecTests, set, t)
+}
