glob/cmd/globdraw/main.go

91 lines
2.1 KiB
Go

package main
import (
"bytes"
"flag"
"fmt"
"github.com/gobwas/glob"
"github.com/gobwas/glob/match"
"math/rand"
"os"
"strings"
"unicode/utf8"
)
func draw(pattern string, m match.Matcher) string {
return fmt.Sprintf(`digraph G {graph[label="%s"];%s}`, pattern, graphviz(m, fmt.Sprintf("%x", rand.Int63())))
}
func graphviz(m match.Matcher, id string) string {
buf := &bytes.Buffer{}
switch matcher := m.(type) {
case match.BTree:
fmt.Fprintf(buf, `"%s"[label="%s"];`, id, matcher.Value.String())
for _, m := range []match.Matcher{matcher.Left, matcher.Right} {
switch n := m.(type) {
case nil:
rnd := rand.Int63()
fmt.Fprintf(buf, `"%x"[label="<nil>"];`, rnd)
fmt.Fprintf(buf, `"%s"->"%x";`, id, rnd)
default:
sub := fmt.Sprintf("%x", rand.Int63())
fmt.Fprintf(buf, `"%s"->"%s";`, id, sub)
fmt.Fprintf(buf, graphviz(n, sub))
}
}
case match.AnyOf:
fmt.Fprintf(buf, `"%s"[label="AnyOf"];`, id)
for _, m := range matcher.Matchers {
rnd := rand.Int63()
fmt.Fprintf(buf, graphviz(m, fmt.Sprintf("%x", rnd)))
fmt.Fprintf(buf, `"%s"->"%x";`, id, rnd)
}
case match.EveryOf:
fmt.Fprintf(buf, `"%s"[label="EveryOf"];`, id)
for _, m := range matcher.Matchers {
rnd := rand.Int63()
fmt.Fprintf(buf, graphviz(m, fmt.Sprintf("%x", rnd)))
fmt.Fprintf(buf, `"%s"->"%x";`, id, rnd)
}
default:
fmt.Fprintf(buf, `"%s"[label="%s"];`, id, m.String())
}
return buf.String()
}
func main() {
pattern := flag.String("p", "", "pattern to draw")
sep := flag.String("s", "", "comma separated list of separators characters")
flag.Parse()
if *pattern == "" {
flag.Usage()
os.Exit(1)
}
var separators []rune
for _, c := range strings.Split(*sep, ",") {
if r, w := utf8.DecodeRuneInString(c); len(c) > w {
fmt.Println("only single charactered separators are allowed")
os.Exit(1)
} else {
separators = append(separators, r)
}
}
glob, err := glob.Compile(*pattern, separators...)
if err != nil {
fmt.Println("could not compile pattern:", err)
os.Exit(1)
}
matcher := glob.(match.Matcher)
fmt.Fprint(os.Stdout, draw(*pattern, matcher))
}