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
|
//
// System.Diagnostics.Contracts.Internal.ContractHelper.cs
//
// Authors:
// Chris Bacon (chrisbacon76@gmail.com)
//
// Copyright 2010 Novell (http://www.novell.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.
//
#if NET_4_0
using System;
using System.Text;
using System.Reflection;
using System.Runtime.ConstrainedExecution;
namespace System.Diagnostics.Contracts.Internal
{
#if NET_4_5
[Obsolete ("Type has been moved to System.Runtime.CompilerServices")]
#endif
public static class ContractHelper
{
[ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
[DebuggerNonUserCode]
public static string RaiseContractFailedEvent (ContractFailureKind failureKind, string userMessage, string conditionText, Exception innerException)
{
StringBuilder msg = new StringBuilder (60);
switch (failureKind) {
case ContractFailureKind.Assert:
msg.Append ("Assertion failed");
break;
case ContractFailureKind.Assume:
msg.Append ("Assumption failed");
break;
case ContractFailureKind.Invariant:
msg.Append ("Invariant failed");
break;
case ContractFailureKind.Postcondition:
msg.Append ("Postcondition failed");
break;
case ContractFailureKind.PostconditionOnException:
msg.Append ("Postcondition failed after throwing an exception");
break;
case ContractFailureKind.Precondition:
msg.Append ("Precondition failed");
break;
default:
throw new NotSupportedException ("Not supported: " + failureKind);
}
if (conditionText != null) {
msg.Append (": ");
msg.Append (conditionText);
} else {
msg.Append ('.');
}
if (userMessage != null) {
msg.Append (" ");
msg.Append (userMessage);
}
string msgString = msg.ToString ();
Exception handlerException = null;
bool unwind = false, handled = false;
var contractFailed = Contract.InternalContractFailedEvent;
if (contractFailed != null) {
// Execute all event handlers
var handlers = contractFailed.GetInvocationList ();
var e = new ContractFailedEventArgs (failureKind, msgString, conditionText, innerException);
foreach (var handler in handlers) {
try {
handler.DynamicInvoke (null, e);
} catch (Exception ex) {
e.SetUnwind ();
// If multiple handlers throw an exception then the specification states that it
// is undetermined which one becomes the InnerException.
handlerException = ex.InnerException;
}
}
unwind = e.Unwind;
handled = e.Handled;
}
if (unwind) {
Exception ex = innerException ?? handlerException;
throw new ContractException (msgString, failureKind, conditionText, userMessage, ex);
}
return handled ? null : msgString;
}
[ReliabilityContract (Consistency.WillNotCorruptState, Cer.Success)]
[DebuggerNonUserCode]
public static void TriggerFailure (ContractFailureKind kind, string displayMessage, string userMessage, string conditionText, Exception innerException)
{
StringBuilder msg = new StringBuilder (50);
if (conditionText != null) {
msg.Append ("Expression: ");
msg.AppendLine (conditionText);
}
msg.Append ("Description: ");
if (displayMessage != null) {
msg.Append (displayMessage);
}
if (Environment.UserInteractive) {
// FIXME: This should trigger an assertion.
// But code will never get here at the moment, as Environment.UserInteractive currently
// always returns false.
throw new ContractShouldAssertException (msg.ToString ());
} else {
// Note that FailFast() currently throws a NotImplementedException()
Environment.FailFast(msg.ToString()/*, new ExecutionEngineException()*/);
}
}
}
}
#endif
|
