/
main.go
153 lines (131 loc) · 3.26 KB
/
main.go
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package main
import (
"bytes"
"fmt"
"io"
"math"
"os"
"strings"
"github.com/gopherjs/gopherjs/js"
"mvdan.cc/sh/syntax"
)
func main() {
exps := js.Module.Get("exports")
exps.Set("syntax", map[string]interface{}{})
stx := exps.Get("syntax")
// Type helpers just for JS
stx.Set("NodeType", func(v interface{}) string {
if v == nil {
return "nil"
}
node, ok := v.(syntax.Node)
if !ok {
throw("NodeType requires a Node argument")
}
typ := fmt.Sprintf("%T", node)
if i := strings.LastIndexAny(typ, "*.]"); i >= 0 {
typ = typ[i+1:]
}
return typ
})
// Parser
stx.Set("NewParser", func(options ...func(interface{})) *js.Object {
p := syntax.NewParser()
jp := js.MakeFullWrapper(jsParser{p})
// Apply the options after we've wrapped the parser, as
// otherwise we cannot internalise the value.
for _, opt := range options {
opt(jp)
}
return jp
})
stx.Set("KeepComments", func(v interface{}) {
syntax.KeepComments(v.(jsParser).Parser)
})
stx.Set("Variant", func(l syntax.LangVariant) func(interface{}) {
if math.IsNaN(float64(l)) {
throw("Variant requires a LangVariant argument")
}
return func(v interface{}) {
syntax.Variant(l)(v.(jsParser).Parser)
}
})
stx.Set("LangBash", syntax.LangBash)
stx.Set("LangPOSIX", syntax.LangPOSIX)
stx.Set("LangMirBSDKorn", syntax.LangMirBSDKorn)
stx.Set("StopAt", func(word string) func(interface{}) {
return func(v interface{}) {
syntax.StopAt(word)(v.(jsParser).Parser)
}
})
// Printer
stx.Set("NewPrinter", func() *js.Object {
p := syntax.NewPrinter()
return js.MakeFullWrapper(jsPrinter{p})
})
// Syntax utilities
stx.Set("Walk", func(node syntax.Node, jsFn func(*js.Object) bool) {
f := func(node syntax.Node) bool {
if node == nil {
return jsFn(nil)
}
return jsFn(js.MakeFullWrapper(node))
}
syntax.Walk(node, f)
})
stx.Set("DebugPrint", func(node syntax.Node) {
syntax.DebugPrint(os.Stdout, node)
})
}
func throw(v interface{}) {
js.Global.Call("$throwRuntimeError", fmt.Sprint(v))
}
// streamReader is an io.Readder wrapper for Node's stream.Readable. See
// https://nodejs.org/api/stream.html#stream_class_stream_readable
// TODO: support https://streams.spec.whatwg.org/#rs-class too?
type streamReader struct {
stream *js.Object
}
func (r streamReader) Read(p []byte) (n int, err error) {
obj := r.stream.Call("read", len(p))
if obj == nil {
return 0, io.EOF
}
bs := []byte(obj.String())
return copy(p, bs), nil
}
type jsParser struct {
*syntax.Parser
}
func adaptReader(src *js.Object) io.Reader {
if src.Get("read") != js.Undefined {
return streamReader{stream: src}
}
return strings.NewReader(src.String())
}
func (p jsParser) Parse(src *js.Object, name string) *js.Object {
f, err := p.Parser.Parse(adaptReader(src), name)
if err != nil {
throw(err)
}
return js.MakeFullWrapper(f)
}
func (p jsParser) Incomplete() bool {
return p.Parser.Incomplete()
}
func (p jsParser) Interactive(src *js.Object, fn func([]*syntax.Stmt) bool) {
err := p.Parser.Interactive(adaptReader(src), fn)
if err != nil {
throw(err)
}
}
type jsPrinter struct {
*syntax.Printer
}
func (p jsPrinter) Print(file *syntax.File) string {
var buf bytes.Buffer
if err := p.Printer.Print(&buf, file); err != nil {
throw(err)
}
return buf.String()
}