91 lines
2.0 KiB
Plaintext
91 lines
2.0 KiB
Plaintext
== Why is this an issue?
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A ``++Select++`` or a chain of ``++If++``/``++Elseif++`` statements is evaluated from top to bottom. At most, only one branch will be executed: the first one with a condition that evaluates to ``++true++``.
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Therefore, duplicating a condition automatically leads to dead code. Usually, this is due to a copy/paste error. At best, it's simply dead code and at worst, it's a bug that is likely to induce further bugs as the code is maintained, and obviously it could lead to unexpected behavior.
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=== Noncompliant code example
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[source,rpg]
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----
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C IF X = 1
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C EXSR SR01
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C ELSEIF X = 1 Noncompliant
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C EXSR SR02
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C ENDIF
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----
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[source,rpg]
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----
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/free
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IF param = 1;
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doX();
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ELSEIF param = 2;
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doY();
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ELSEIF param = 1; // Noncompliant
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doZ();
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ENDIF;
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SELECT;
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WHEN param = 1;
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doX();
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WHEN param = 2;
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doY();
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WHEN param = 1; // Noncompliant
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doZ();
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ENDSL;
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/end-free
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----
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=== Compliant solution
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[source,rpg]
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----
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C IF X = 1
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C EXSR SR01
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C ELSEIF X = 2
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C EXSR SR02
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C ENDIF
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----
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[source,rpg]
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----
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/free
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IF param = 1;
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doX();
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ELSEIF param = 2;
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doY();
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ELSEIF param = 3;
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doZ();
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ENDIF;
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SELECT;
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WHEN param = 1;
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doX();
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WHEN param = 2;
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doY();
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WHEN param = 3;
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doZ();
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ENDSL;
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/end-free
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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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include::../message.adoc[]
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include::../highlighting.adoc[]
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'''
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== Comments And Links
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(visible only on this page)
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include::../comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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