• Home
• fr.sii.sonar
• sonar-web-frontend-js
• 2.0.0
• source code
• W122.html

×

Project download

Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance.
Project price only 1 $

You can buy this project and download/modify it how often you want.

rules.jshint.W122.html Maven / Gradle / Ivy

    
When do I get this error?
The "Invalid typeof value '{a}'" error is thrown when JSHint encounters a
comparison with a typeof expression on one side and an invalid string literal
on the other. In the following example we have a function that will return
true if the argument is of type "bool":
​x
 
1
function demo(a) {
2
    return typeof a === "bool";
3
}
4
​
JSHint found 1 error
Which linter should be used for this code snippet:
 JSLint JSHint ESLint
Which version of the linter should be used:
Update
Version 2.9.0
Line 2:
Invalid typeof value 'bool'

This functionality was introduced in JSHint 2.3.0. Prior versions do not raise
any error in this situation. Neither JSLint nor ESLint raises any error in this
situation.
Why do I get this error?
This error is raised to highlight code that is unlikely to work as you
expect. The typeof operator returns one of a few possible values that are
given by the ECMAScript specification (although in some situations in certain
browsers it will return one of two extra possibilities). The possible values are
as follows ([ES5 §11.4.3]):

"undefined" - when the operand has the undefined value

"boolean" - when the operand has a literal boolean value

"string" - when the operand has a literal string value

"number" - when the operand has a literal numeric value

"function" - when the operand is an object and implements the internal
[[Call]] property

"object" - when the operand has the null value or is an object that does
not implement the internal [[Call]] property


In certain situations the operator could also return "xml" or "unknown" but
you're unlikely to come across these. JSHint requires that any comparison with a
typeof expression uses one of these strings. If a different string is used the
condition will always evaluate to false since it is not possible for the
typeof operator to ever return the value you're using. To solve this issue
simply use a valid value:
4
 
1
function demo(a) {
2
    return typeof a === "boolean";
3
}
4
​
JSHint found no errors
Which linter should be used for this code snippet:
 JSLint JSHint ESLint
Which version of the linter should be used:
Update
Version 2.9.0

In JSHint 1.0.0 and above you have the ability to ignore any warning with a
special option syntax. The identifier of this warning is W122.
This means you can tell JSHint to not issue this warning with the /*jshint
-W122 */ directive. You can also set the sub option to true.