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There is a newer version: 5.0.0.6962

Why is this an issue?
Nested code blocks can be used to create a new scope: variables declared within that block cannot be accessed from the outside, and their lifetime
end at the end of the block. However, this only happens when you use ES6 let or const keywords, a class declaration or a
function declaration (in strict mode). Otherwise, the nested block is redundant and should be removed.
Exceptions
The rule does not apply to the following cases:

   Block statements containing variable declarations using let or const keywords or class declarations are not redundant
  as they create a new scope. 

{
    let x = 1;
}


   The same applies to function declarations in strict
  mode 

"use strict";
{
    function foo() {}
}


   The rule also does not apply to the blocks that are part of the control flow. 

if (condition) {
    doSomething();
}

How to fix it
The nested code blocks should be extracted into separate methods.
Code examples
Noncompliant code example
{   // Noncompliant: redundant code block
    var foo = bar();
}

if (condition) {
    doSomething();
    {   // Noncompliant: redundant code block
        doOtherStuff();
    }
}

Compliant solution
var foo = bar();

if (condition) {
    doSomething();
    doOtherStuff();
}

Resources
Documentation

   Wikipedia - Single Responsibility Principle 
   MDN web docs - block statement 
   MDN web docs - var 
   MDN web docs - let 
   MDN web docs - const 
   MDN web docs - class declaration 
   MDN web docs - function declaration 
   MDN web docs - strict mode