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noMisrefactoredShorthandAssign (since v1.3.0)

Diagnostic Category: lint/suspicious/noMisrefactoredShorthandAssign

Sources:

Disallow shorthand assign when variable appears on both sides.

This rule helps to avoid potential bugs related to incorrect assignments or unintended side effects that may occur during refactoring.

Examples

Section titled Examples

Invalid

Section titled Invalid
a += a + b
code-block.js:1:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Variable appears on both sides of an assignment operation.
  
  > 1 │ a += a + b
      │ ^^^^^^^^^^
    2 │ 
  
  ℹ This assignment might be the result of a wrong refactoring.
  
  ℹ Unsafe fix: Use a += b instead.
  
    1 │ a·+=·a·+·b
      │      ---- 

a -= a - b
code-block.js:1:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Variable appears on both sides of an assignment operation.
  
  > 1 │ a -= a - b
      │ ^^^^^^^^^^
    2 │ 
  
  ℹ This assignment might be the result of a wrong refactoring.
  
  ℹ Unsafe fix: Use a -= b instead.
  
    1 │ a·-=·a·-·b
      │      ---- 

a *= a * b
code-block.js:1:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Variable appears on both sides of an assignment operation.
  
  > 1 │ a *= a * b
      │ ^^^^^^^^^^
    2 │ 
  
  ℹ This assignment might be the result of a wrong refactoring.
  
  ℹ Unsafe fix: Use a *= b instead.
  
    1 │ a·*=·a·*·b
      │      ----

Valid

Section titled Valid
a += b
a = a + b
a = a - b
Section titled Related links