1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
//
// SimplifyAnonymousMethodToDelegateIssue.cs
//
// Author:
// Mike Krüger <mkrueger@xamarin.com>
//
// Copyright (c) 2013 Xamarin Inc. (http://xamarin.com)
//
// 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.
using System;
using System.Collections.Generic;
using System.Linq;
using ICSharpCode.NRefactory.PatternMatching;
using ICSharpCode.NRefactory.Semantics;
using ICSharpCode.NRefactory.CSharp.Resolver;
using ICSharpCode.NRefactory.TypeSystem;
using ICSharpCode.NRefactory.Refactoring;
namespace ICSharpCode.NRefactory.CSharp.Refactoring
{
[IssueDescription("Simplify anonymous method to delegate",
Description = "Shows anonymous methods that can be simplified.",
Category = IssueCategories.CodeQualityIssues,
Severity = Severity.Warning,
ResharperDisableKeyword = "ConvertClosureToMethodGroup")]
public class SimplifyAnonymousMethodToDelegateIssue : ICodeIssueProvider
{
public IEnumerable<CodeIssue> GetIssues(BaseRefactoringContext context)
{
return new GatherVisitor(context).GetIssues();
}
class GatherVisitor : GatherVisitorBase<SimplifyAnonymousMethodToDelegateIssue>
{
public GatherVisitor (BaseRefactoringContext ctx) : base (ctx)
{
}
static Pattern pattern = new Choice {
new BlockStatement {
new ReturnStatement (new AnyNode ("invoke"))
},
new AnyNode ("invoke")
};
static InvocationExpression AnalyzeBody(AstNode body)
{
var m = pattern.Match(body);
if (m.Success)
return m.Get("invoke").Single () as InvocationExpression;
return null;
}
static bool IsSimpleTarget(Expression target)
{
if (target is IdentifierExpression)
return true;
var mref = target as MemberReferenceExpression;
if (mref != null)
return IsSimpleTarget (mref.Target);
var pref = target as PointerReferenceExpression;
if (pref != null)
return IsSimpleTarget (pref.Target);
return false;
}
void AnalyzeExpression(AstNode expression, AstNode body, AstNodeCollection<ParameterDeclaration> parameters)
{
var invocation = AnalyzeBody(body);
if (invocation == null)
return;
if (!IsSimpleTarget (invocation.Target))
return;
var rr = ctx.Resolve (invocation) as CSharpInvocationResolveResult;
if (rr == null)
return;
var lambdaParameters = parameters.ToList();
var arguments = rr.GetArgumentsForCall();
if (lambdaParameters.Count != arguments.Count)
return;
for (int i = 0; i < arguments.Count; i++) {
var arg = UnpackImplicitIdentityOrReferenceConversion(arguments[i]) as LocalResolveResult;
if (arg == null || arg.Variable.Name != lambdaParameters[i].Name)
return;
}
var returnConv = ctx.GetConversion(invocation);
if (returnConv.IsExplicit || !(returnConv.IsIdentityConversion || returnConv.IsReferenceConversion))
return;
AddIssue(expression, ctx.TranslateString("Expression can be reduced to delegate"), script => {
var validTypes = CreateFieldAction.GetValidTypes (ctx.Resolver, expression).ToList ();
if (validTypes.Any (t => t.FullName == "System.Func" && t.TypeParameterCount == 1 + parameters.Count) && validTypes.Any (t => t.FullName == "System.Action")) {
if (rr != null && rr.Member.ReturnType.Kind != TypeKind.Void) {
var builder = ctx.CreateTypeSystemAstBuilder (expression);
var type = builder.ConvertType(new TopLevelTypeName("System", "Func", 1));
var args = type.GetChildrenByRole(Roles.TypeArgument);
args.Clear ();
foreach (var pde in parameters) {
args.Add (builder.ConvertType (ctx.Resolve (pde).Type));
}
args.Add (builder.ConvertType (rr.Member.ReturnType));
script.Replace(expression, new CastExpression (type, invocation.Target.Clone()));
return;
}
}
script.Replace(expression, invocation.Target.Clone());
});
}
static ResolveResult UnpackImplicitIdentityOrReferenceConversion(ResolveResult rr)
{
var crr = rr as ConversionResolveResult;
if (crr != null && crr.Conversion.IsImplicit && (crr.Conversion.IsIdentityConversion || crr.Conversion.IsReferenceConversion))
return crr.Input;
return rr;
}
public override void VisitLambdaExpression(LambdaExpression lambdaExpression)
{
base.VisitLambdaExpression(lambdaExpression);
AnalyzeExpression(lambdaExpression, lambdaExpression.Body, lambdaExpression.Parameters);
}
public override void VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression)
{
base.VisitAnonymousMethodExpression(anonymousMethodExpression);
AnalyzeExpression(anonymousMethodExpression, anonymousMethodExpression.Body, anonymousMethodExpression.Parameters);
}
}
}
}
|
