1// Protocol Buffers for Go with Gadgets
2//
3// Copyright (c) 2013, The GoGo Authors. All rights reserved.
4// http://github.com/gogo/protobuf
5//
6// Redistribution and use in source and binary forms, with or without
7// modification, are permitted provided that the following conditions are
8// met:
9//
10//     * Redistributions of source code must retain the above copyright
11// notice, this list of conditions and the following disclaimer.
12//     * Redistributions in binary form must reproduce the above
13// copyright notice, this list of conditions and the following disclaimer
14// in the documentation and/or other materials provided with the
15// distribution.
16//
17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
29/*
30The enumstringer (experimental) plugin generates a String method for each enum.
31
32It is enabled by the following extensions:
33
34  - enum_stringer
35  - enum_stringer_all
36
37This package is subject to change.
38
39*/
40package enumstringer
41
42import (
43	"github.com/gogo/protobuf/gogoproto"
44	"github.com/gogo/protobuf/protoc-gen-gogo/generator"
45)
46
47type enumstringer struct {
48	*generator.Generator
49	generator.PluginImports
50	atleastOne bool
51	localName  string
52}
53
54func NewEnumStringer() *enumstringer {
55	return &enumstringer{}
56}
57
58func (p *enumstringer) Name() string {
59	return "enumstringer"
60}
61
62func (p *enumstringer) Init(g *generator.Generator) {
63	p.Generator = g
64}
65
66func (p *enumstringer) Generate(file *generator.FileDescriptor) {
67	p.PluginImports = generator.NewPluginImports(p.Generator)
68	p.atleastOne = false
69
70	p.localName = generator.FileName(file)
71
72	strconvPkg := p.NewImport("strconv")
73
74	for _, enum := range file.Enums() {
75		if !gogoproto.IsEnumStringer(file.FileDescriptorProto, enum.EnumDescriptorProto) {
76			continue
77		}
78		if gogoproto.IsGoEnumStringer(file.FileDescriptorProto, enum.EnumDescriptorProto) {
79			panic("Go enum stringer conflicts with new enumstringer plugin: please use gogoproto.goproto_enum_stringer or gogoproto.goproto_enum_string_all and set it to false")
80		}
81		p.atleastOne = true
82		ccTypeName := generator.CamelCaseSlice(enum.TypeName())
83		p.P("func (x ", ccTypeName, ") String() string {")
84		p.In()
85		p.P(`s, ok := `, ccTypeName, `_name[int32(x)]`)
86		p.P(`if ok {`)
87		p.In()
88		p.P(`return s`)
89		p.Out()
90		p.P(`}`)
91		p.P(`return `, strconvPkg.Use(), `.Itoa(int(x))`)
92		p.Out()
93		p.P(`}`)
94	}
95
96	if !p.atleastOne {
97		return
98	}
99
100}
101
102func init() {
103	generator.RegisterPlugin(NewEnumStringer())
104}
105