List variable decralation in package

pkgvars.go

package main

import (
	"fmt"
	"go/ast"
	"go/parser"
	"go/token"
	"os"
	"strings"
)

func main() {
	fset := token.NewFileSet() // positions are relative to fset
	pkgs, _ := parser.ParseDir(fset, os.Args[1], nil, 0)

	for pname, p := range pkgs {
		if !strings.HasSuffix(pname, "_test") {
			for _, f := range p.Files {
				for _, d := range f.Decls {
					switch gd := d.(type) {
					case *ast.GenDecl:
						if gd.Tok == token.VAR {
							for _, s := range gd.Specs {
								fmt.Println(s.(*ast.ValueSpec).Names[0].Name)
							}
						}
					}
				}
			}
		}
	}
}