feature: refactor api parse to g4 (#365)

* feature: refactor api parse to g4

* new g4 parser

* add CHANGE_LOG.MD

* refactor

* fix byte bug

* refactor

* optimized

* optimized

* revert

* update readme.md

* update readme.md

* update readme.md

* update readme.md

* remove no need

* fix java gen

* add upgrade

* resolve confilits

Co-authored-by: anqiansong <anqiansong@xiaoheiban.cn>

tools/goctl/api/parser/g4/ast/info.go

@@ -0,0 +1,67 @@
+package ast
+
+import (
+	"github.com/tal-tech/go-zero/tools/goctl/api/parser/g4/gen/api"
+)
+
+type InfoExpr struct {
+	Info Expr
+	Lp   Expr
+	Rp   Expr
+	Kvs  []*KvExpr
+}
+
+func (v *ApiVisitor) VisitInfoSpec(ctx *api.InfoSpecContext) interface{} {
+	var expr InfoExpr
+	expr.Info = v.newExprWithToken(ctx.GetInfoToken())
+	expr.Lp = v.newExprWithToken(ctx.GetLp())
+	expr.Rp = v.newExprWithToken(ctx.GetRp())
+	list := ctx.AllKvLit()
+	for _, each := range list {
+		kvExpr := each.Accept(v).(*KvExpr)
+		expr.Kvs = append(expr.Kvs, kvExpr)
+	}
+
+	if v.infoFlag {
+		v.panic(expr.Info, "duplicate declaration 'info'")
+	}
+
+	return &expr
+}
+
+func (i *InfoExpr) Format() error {
+	// todo
+	return nil
+}
+
+func (i *InfoExpr) Equal(v interface{}) bool {
+	if v == nil {
+		return false
+	}
+
+	info, ok := v.(*InfoExpr)
+	if !ok {
+		return false
+	}
+
+	if !i.Info.Equal(info.Info) {
+		return false
+	}
+
+	var expected, actual []*KvExpr
+	expected = append(expected, i.Kvs...)
+	actual = append(actual, info.Kvs...)
+
+	if len(expected) != len(actual) {
+		return false
+	}
+
+	for index, each := range expected {
+		ac := actual[index]
+		if !each.Equal(ac) {
+			return false
+		}
+	}
+
+	return true
+}