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.
68 lines
1.6 KiB
Plaintext
68 lines
1.6 KiB
Plaintext
== Why is this an issue?
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When either the equality operator in a test for ``++null++`` or ``++undefined++``, or the logical operator that follows it is reversed, the code has the appearance of safely null-testing the object before dereferencing it. Unfortunately the effect is just the opposite - the object is null-tested and then dereferenced only if it is ``++null++``/``++undefined++``, leading to a guaranteed ``++TypeError++``.
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=== Noncompliant code example
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[source,javascript]
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----
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if (str == null && str.length == 0) {
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console.log("String is empty");
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}
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if (str == undefined && str.length == 0) {
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console.log("String is empty");
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}
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if (str != null || str.length > 0) {
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console.log("String is not empty");
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}
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if (str != undefined || str.length > 0) {
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console.log("String is not empty");
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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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if (str != null && str.length == 0) {
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console.log("String is empty");
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}
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if (str != undefined && str.length == 0) {
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console.log("String is empty");
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}
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if (str == null || str.length > 0) {
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console.log("String is not empty");
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}
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if (str == undefined || str.length > 0) {
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console.log("String is not empty");
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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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include::../message.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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=== on 10 Mar 2015, 14:56:30 Ann Campbell wrote:
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submitted for your approval [~linda.martin]
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=== on 10 Mar 2015, 15:14:19 Linda Martin wrote:
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Perfect !
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include::../comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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