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.
62 lines
1.3 KiB
Plaintext
62 lines
1.3 KiB
Plaintext
== Why is this an issue?
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``++GetHashCode++`` is used to file an object in a ``++Dictionary++`` or ``++Hashtable++``. If ``++GetHashCode++`` uses non-``++readonly++`` fields and those fields change after the object is stored, the object immediately becomes mis-filed in the ``++Hashtable++``. Any subsequent test to see if the object is in the ``++Hashtable++`` will return a false negative.
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=== Noncompliant code example
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[source,csharp]
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----
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public class Person
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{
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public int age;
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public string name;
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public override int GetHashCode()
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{
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int hash = 12;
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hash += this.age.GetHashCode(); // Noncompliant
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hash += this.name.GetHashCode(); // Noncompliant
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return hash;
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}
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----
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=== Compliant solution
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[source,csharp]
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----
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public class Person
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{
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public readonly DateTime birthday;
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public string name;
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public override int GetHashCode()
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{
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int hash = 12;
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hash += this.birthday.GetHashCode();
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return hash;
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}
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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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Refactor 'GetHashCode' to not reference mutable fields.
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=== Highlighting
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* primary: method name
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* secondary: uses of mutable fields
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** message: Remove this use of "xxx" or make it "readonly".
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endif::env-github,rspecator-view[]
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