16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
88 lines
2.0 KiB
Plaintext
88 lines
2.0 KiB
Plaintext
== Why is this an issue?
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Once you modify a closure, any use of it could provide unexpected results.
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=== Noncompliant code example
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[source,csharp]
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----
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var x = 0;
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Func<int> f1 = () => x; // Noncompliant
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x = 1;
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Console.WriteLine(f1());
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var input = new[] { 1, 2, 3 };
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var fs = new List<Func<int>>();
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for (var i = 0; i < input.Length; i++) {
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Func<int> f = () => input[i]; // Noncompliant
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fs.Add(f);
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}
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Console.WriteLine(fs[0]()); //Access to modified closure yields Exception
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----
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=== Compliant solution
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[source,csharp]
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----
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var x = 0;
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var xx = x;
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Func<int> f = () => xx;
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x = 1;
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Console.WriteLine(f());
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var input = new[] { 1, 2, 3 };
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var fs = new List<Func<int>>();
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for (var i = 0; i < input.Length; i++) {
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var ii = i;
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Func<int> f = () => input[ii];
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fs.Add(f);
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}
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Console.WriteLine(fs[0]());
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----
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or
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[source,csharp]
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----
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var input = new[] { 1, 2, 3 };
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var fs = input.Select(t => (Func<int>) (() => t)).ToList();
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Console.WriteLine(fs[0]());
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Remove the access to the modified closure.
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'''
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== Comments And Links
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(visible only on this page)
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=== on 20 Mar 2015, 16:08:06 Ann Campbell wrote:
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\[~tamas.vajk] is the problem really in accessing the modified closure, or is the problem that the closure was modified at all?
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=== on 23 Mar 2015, 07:28:58 Tamas Vajk wrote:
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\[~ann.campbell.2] the problem is that the closure was modified, and then it was used.
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=== on 8 Jun 2015, 11:44:37 Tamas Vajk wrote:
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\[~ann.campbell.2] this RSPEC doesn't seem to be finished, it is missing a lot of metadata (sqale, severity, ...)
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=== on 8 Jun 2015, 12:27:22 Ann Campbell wrote:
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Sorry about that [~tamas.vajk]. Take a look now.
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Also, I've set this rule to Blocker. Do you think that's too severe?
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=== on 9 Jun 2015, 06:53:16 Tamas Vajk wrote:
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\[~ann.campbell.2] Thanks, it looks good. The blocker severity seems okay, the rule detects bugs.
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endif::env-github,rspecator-view[]
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