add Parent field to all Visitee (emicklei#68)

* add Parent field to all Visitee

comment.go

@@ -141,3 +141,6 @@ func mergeOrReturnComment(elements []Visitee, lit string, pos scanner.Position)
 	last.Merge(com)
 	return nil
 }
+
+// parent is part of elementContainer
+func (c *Comment) parent(Visitee) {}

enum.go

@@ -33,6 +33,7 @@ type Enum struct {
 	Comment  *Comment
 	Name     string
 	Elements []Visitee
+	Parent   Visitee
 }
 
 // Accept dispatches the call to the visitor.
@@ -47,6 +48,7 @@ func (e *Enum) Doc() *Comment {
 
 // addElement is part of elementContainer
 func (e *Enum) addElement(v Visitee) {
+	v.parent(e)
 	e.Elements = append(e.Elements, v)
 }
 
@@ -79,7 +81,7 @@ func (e *Enum) parse(p *Parser) error {
 		switch tok {
 		case tCOMMENT:
 			if com := mergeOrReturnComment(e.elements(), lit, pos); com != nil { // not merged?
-				e.Elements = append(e.Elements, com)
+				e.addElement(com)
 			}
 		case tOPTION:
 			v := new(Option)
@@ -89,7 +91,7 @@ func (e *Enum) parse(p *Parser) error {
 			if err != nil {
 				return err
 			}
-			e.Elements = append(e.Elements, v)
+			e.addElement(v)
 		case tRIGHTCURLY, tEOF:
 			goto done
 		case tSEMICOLON:
@@ -103,7 +105,7 @@ func (e *Enum) parse(p *Parser) error {
 			if err != nil {
 				return err
 			}
-			e.Elements = append(e.Elements, f)
+			e.addElement(f)
 		}
 	}
 done:
@@ -113,6 +115,9 @@ done:
 	return nil
 }
 
+// parent is part of elementContainer
+func (e *Enum) parent(p Visitee) { e.Parent = p }
+
 // EnumField is part of the body of an Enum.
 type EnumField struct {
 	Position scanner.Position
@@ -123,6 +128,7 @@ type EnumField struct {
 	ValueOption   *Option
 	Elements      []Visitee // such as Option and Comment
 	InlineComment *Comment
+	Parent        Visitee
 }
 
 // Accept dispatches the call to the visitor.
@@ -169,7 +175,7 @@ func (f *EnumField) parse(p *Parser) error {
 			}
 			// update deprecated field with the last option found
 			f.ValueOption = o
-			f.Elements = append(f.Elements, o)
+			f.addElement(o)
 			pos, tok, lit = p.next()
 			if tok == tCOMMA {
 				continue
@@ -184,3 +190,11 @@ func (f *EnumField) parse(p *Parser) error {
 	}
 	return nil
 }
+
+// addElement is part of elementContainer
+func (f *EnumField) addElement(v Visitee) {
+	v.parent(f)
+	f.Elements = append(f.Elements, v)
+}
+
+func (f *EnumField) parent(v Visitee) { f.Parent = v }

extensions.go

@@ -34,6 +34,7 @@ type Extensions struct {
 	Comment       *Comment
 	Ranges        []Range
 	InlineComment *Comment
+	Parent        Visitee
 }
 
 // inlineComment is part of commentInliner.
@@ -55,3 +56,6 @@ func (e *Extensions) parse(p *Parser) error {
 	e.Ranges = list
 	return nil
 }
+
+// parent is part of elementContainer
+func (e *Extensions) parent(p Visitee) { e.Parent = p }

field.go

@@ -36,6 +36,7 @@ type Field struct {
 	Sequence      int
 	Options       []*Option
 	InlineComment *Comment
+	Parent        Visitee
 }
 
 // inlineComment is part of commentInliner.
@@ -175,3 +176,5 @@ func (f *MapField) parse(p *Parser) error {
 	}
 	return parseFieldAfterType(f.Field, p)
 }
+
+func (f *Field) parent(v Visitee) { f.Parent = v }

group.go

@@ -38,6 +38,7 @@ type Group struct {
 	Required bool
 	Sequence int
 	Elements []Visitee
+	Parent   Visitee
 }
 
 // Accept dispatches the call to the visitor.
@@ -47,6 +48,7 @@ func (g *Group) Accept(v Visitor) {
 
 // addElement is part of elementContainer
 func (g *Group) addElement(v Visitee) {
+	v.parent(g)
 	g.Elements = append(g.Elements, v)
 }
 
@@ -92,3 +94,5 @@ func (g *Group) parse(p *Parser) error {
 	}
 	return parseMessageBody(p, g)
 }
+
+func (g *Group) parent(v Visitee) { g.Parent = v }

import.go

@@ -34,6 +34,7 @@ type Import struct {
 	Filename      string
 	Kind          string // weak, public, <empty>
 	InlineComment *Comment
+	Parent        Visitee
 }
 
 func (i *Import) parse(p *Parser) error {
@@ -67,3 +68,5 @@ func (i *Import) inlineComment(c *Comment) {
 func (i *Import) Doc() *Comment {
 	return i.Comment
 }
+
+func (i *Import) parent(v Visitee) { i.Parent = v }

message.go

@@ -34,6 +34,7 @@ type Message struct {
 	Name     string
 	IsExtend bool
 	Elements []Visitee
+	Parent   Visitee
 }
 
 func (m *Message) groupName() string {
@@ -209,6 +210,7 @@ func (m *Message) Accept(v Visitor) {
 
 // addElement is part of elementContainer
 func (m *Message) addElement(v Visitee) {
+	v.parent(m)
 	m.Elements = append(m.Elements, v)
 }
 
@@ -226,3 +228,5 @@ func (m *Message) takeLastComment(expectedOnLine int) (last *Comment) {
 func (m *Message) Doc() *Comment {
 	return m.Comment
 }
+
+func (m *Message) parent(v Visitee) { m.Parent = v }

oneof.go

@@ -33,10 +33,12 @@ type Oneof struct {
 	Comment  *Comment
 	Name     string
 	Elements []Visitee
+	Parent   Visitee
 }
 
 // addElement is part of elementContainer
 func (o *Oneof) addElement(v Visitee) {
+	v.parent(o)
 	o.Elements = append(o.Elements, v)
 }
 
@@ -71,7 +73,7 @@ func (o *Oneof) parse(p *Parser) error {
 		switch tok {
 		case tCOMMENT:
 			if com := mergeOrReturnComment(o.elements(), lit, pos); com != nil { // not merged?
-				o.Elements = append(o.Elements, com)
+				o.addElement(com)
 			}
 		case tIDENT:
 			f := newOneOfField()
@@ -81,23 +83,23 @@ func (o *Oneof) parse(p *Parser) error {
 			if err := parseFieldAfterType(f.Field, p); err != nil {
 				return err
 			}
-			o.Elements = append(o.Elements, f)
+			o.addElement(f)
 		case tGROUP:
 			g := new(Group)
 			g.Position = pos
 			g.Comment, o.Elements = takeLastCommentIfEndsOnLine(o.elements(), pos.Line-1)
 			if err := g.parse(p); err != nil {
 				return err
 			}
-			o.Elements = append(o.Elements, g)
+			o.addElement(g)
 		case tOPTION:
 			opt := new(Option)
 			opt.Position = pos
 			opt.Comment, o.Elements = takeLastCommentIfEndsOnLine(o.elements(), pos.Line-1)
 			if err := opt.parse(p); err != nil {
 				return err
 			}
-			o.Elements = append(o.Elements, opt)
+			o.addElement(opt)
 		case tSEMICOLON:
 			maybeScanInlineComment(p, o)
 			// continue
@@ -134,3 +136,5 @@ func (o *OneOfField) Accept(v Visitor) {
 func (o *OneOfField) Doc() *Comment {
 	return o.Comment
 }
+
+func (o *Oneof) parent(v Visitee) { o.Parent = v }

option.go

@@ -38,6 +38,7 @@ type Option struct {
 	IsEmbedded          bool
 	AggregatedConstants []*NamedLiteral
 	InlineComment       *Comment
+	Parent              Visitee
 }
 
 // parse reads an Option body
@@ -233,3 +234,5 @@ func parseAggregateConstants(p *Parser, container interface{}) (list []*NamedLit
 		list = append(list, &NamedLiteral{Name: key, Literal: l, PrintsColon: printsColon})
 	}
 }
+
+func (o *Option) parent(v Visitee) { o.Parent = v }

package.go

@@ -31,6 +31,7 @@ type Package struct {
 	Comment       *Comment
 	Name          string
 	InlineComment *Comment
+	Parent        Visitee
 }
 
 // Doc is part of Documented
@@ -58,3 +59,5 @@ func (p *Package) Accept(v Visitor) {
 func (p *Package) inlineComment(c *Comment) {
 	p.InlineComment = c
 }
+
+func (p *Package) parent(v Visitee) { p.Parent = v }

parent_accessor.go

@@ -0,0 +1,88 @@
+// Copyright (c) 2018 Ernest Micklei
+//
+// MIT License
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package proto
+
+func getParent(child Visitee) Visitee {
+	if child == nil {
+		return nil
+	}
+	pa := new(parentAccessor)
+	child.Accept(pa)
+	return pa.parent
+}
+
+type parentAccessor struct {
+	parent Visitee
+}
+
+func (p *parentAccessor) VisitMessage(m *Message) {
+	p.parent = m.Parent
+}
+func (p *parentAccessor) VisitService(v *Service) {
+	p.parent = v.Parent
+}
+func (p *parentAccessor) VisitSyntax(s *Syntax) {
+	p.parent = s.Parent
+}
+func (p *parentAccessor) VisitPackage(pkg *Package) {
+	p.parent = pkg.Parent
+}
+func (p *parentAccessor) VisitOption(o *Option) {
+	p.parent = o.Parent
+}
+func (p *parentAccessor) VisitImport(i *Import) {
+	p.parent = i.Parent
+}
+func (p *parentAccessor) VisitNormalField(i *NormalField) {
+	p.parent = i.Parent
+}
+func (p *parentAccessor) VisitEnumField(i *EnumField) {
+	p.parent = i.Parent
+}
+func (p *parentAccessor) VisitEnum(e *Enum) {
+	p.parent = e.Parent
+}
+func (p *parentAccessor) VisitComment(e *Comment) {}
+func (p *parentAccessor) VisitOneof(o *Oneof) {
+	p.parent = o.Parent
+}
+func (p *parentAccessor) VisitOneofField(o *OneOfField) {
+	p.parent = o.Parent
+}
+func (p *parentAccessor) VisitReserved(rs *Reserved) {
+	p.parent = rs.Parent
+}
+func (p *parentAccessor) VisitRPC(rpc *RPC) {
+	p.parent = rpc.Parent
+}
+func (p *parentAccessor) VisitMapField(f *MapField) {
+	p.parent = f.Parent
+}
+func (p *parentAccessor) VisitGroup(g *Group) {
+	p.parent = g.Parent
+}
+func (p *parentAccessor) VisitExtensions(e *Extensions) {
+	p.parent = e.Parent
+}
+func (p *parentAccessor) VisitProto(*Proto) {}