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.
60 lines
1.6 KiB
Plaintext
60 lines
1.6 KiB
Plaintext
== Why is this an issue?
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Once you've made a selection, you typically want to know whether it actually found anything. Since selectors _always_ return an object (the set of selected DOM elements), the best way to see whether your selection found anything is to test the returned object's ``++.length++`` property.
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=== Noncompliant code example
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[source,javascript]
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----
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if ( $( "div.foo" ) ) { // Noncompliant
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// this code always runs, even when the selector didn't match any elements
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// ...
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}
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----
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=== Compliant solution
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[source,javascript]
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----
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// Testing whether a selection contains elements.
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if ( $( "div.foo" ).length > 0) {
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// this code only runs if elements were found
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// ...
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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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Use the "length" property to see whether this selection contains elements.
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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 26 Mar 2015, 17:11:46 Linda Martin wrote:
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\[~ann.campbell.2] Assigned for review and completion. The description is a copy/paste of \https://learn.jquery.com/using-jquery-core/selecting-elements/, I was afraid that if I started to rephrase it would not make any sens anymore.
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=== on 27 Mar 2015, 15:24:13 Ann Campbell wrote:
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double-check me, please [~linda.martin]
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=== on 19 May 2015, 15:54:00 Linda Martin wrote:
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Reviewed.
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=== on 24 Apr 2017, 10:24:45 Elena Vilchik wrote:
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\[~ann.campbell.2] why minor?
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=== on 1 Nov 2019, 17:29:53 Elena Vilchik wrote:
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See \https://github.com/SonarSource/SonarJS/issues/1698
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endif::env-github,rspecator-view[]
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