d3cfe19d7e
Co-authored-by: Marco Borgeaud <89914223+marco-antognini-sonarsource@users.noreply.github.com>
85 lines
2.7 KiB
Plaintext
85 lines
2.7 KiB
Plaintext
== Why is this an issue?
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Both ``++if-else++`` chains and ``++switch++`` statements are used for conditional branching, but they differ in their syntax and the way they handle multiple conditions.
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* In an ``++if-else++`` chain, each condition is checked in order, and only the block associated with the first true condition is executed. If no condition is true, the code inside the ``++else++`` block (if present) will be executed.
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* In a ``++switch++`` statement, the expression is evaluated once, and its value is compared against each case. If a matching case is found, the corresponding block of code is executed. The ``++break++`` statement is used to exit the ``++switch++`` block after a match. If no case matches the expression, the code inside the ``++default++`` block (if present) will be executed.
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Having the same condition in both ``++if-else++`` chains and ``++switch++`` cases can lead to unreachable code and a potential source of bugs. It defeats the purpose of conditional branching and can make the code harder to read and maintain.
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[source,javascript,diff-id=1,diff-type=noncompliant]
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----
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if (event === 1) {
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openWindow();
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} else if (event === 2) {
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closeWindow();
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} else if (event === 1) { // Noncompliant: Duplicated condition 'event === 1'
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moveWindowToTheBackground();
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}
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switch (event) {
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case 1:
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openWindow();
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break;
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case 2:
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closeWindow();
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break;
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case 1: // Noncompliant: Duplicated case '1'
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moveWindowToTheBackground();
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break;
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}
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----
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Carefully review your conditions and ensure that they are not duplicated across the ``++if-else++`` chain or ``++switch++`` statement. Use distinct conditions and default blocks to cover all scenarios without redundant checks.
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[source,javascript,diff-id=1,diff-type=compliant]
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----
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if (event === 1) {
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openWindow();
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} else if (event === 2) {
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closeWindow();
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} else if (event === 3) {
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moveWindowToTheBackground();
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}
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switch (event) {
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case 1:
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openWindow();
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break;
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case 2:
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closeWindow();
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break;
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case 3:
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moveWindowToTheBackground();
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break;
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}
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----
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== Resources
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=== Documentation
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* MDN web docs - link:++https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/if...else++[``++if...else++``]
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* MDN web docs - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/switch[``++switch++``]
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* Wikipedia - https://en.wikipedia.org/wiki/Unreachable_code[Unreachable code]
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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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This branch duplicates the one on line n.
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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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