⏎ Lint Rules

noFunctionAssign (since v0.7.0)

This rule is recommended by Rome.

Disallow reassigning function declarations.

Examples

Invalid

function foo() { };
foo = bar;

correctness/noFunctionAssign.js:1:10 lint/correctness/noFunctionAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Do not reassign a function declaration.
  
  > 1 │ function foo() { };
      │          ^^^
    2 │ foo = bar;
    3 │ 
  
  ℹ Reassigned here.
  
    1 │ function foo() { };
  > 2 │ foo = bar;
      │ ^^^
    3 │ 
  
  ℹ Use a local variable instead.
  

function foo() {
    foo = bar;
 }

correctness/noFunctionAssign.js:1:10 lint/correctness/noFunctionAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Do not reassign a function declaration.
  
  > 1 │ function foo() {
      │          ^^^
    2 │     foo = bar;
    3 │  }
  
  ℹ Reassigned here.
  
    1 │ function foo() {
  > 2 │     foo = bar;
      │     ^^^
    3 │  }
    4 │ 
  
  ℹ Use a local variable instead.
  

foo = bar;
function foo() { };

correctness/noFunctionAssign.js:2:10 lint/correctness/noFunctionAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Do not reassign a function declaration.
  
    1 │ foo = bar;
  > 2 │ function foo() { };
      │          ^^^
    3 │ 
  
  ℹ Reassigned here.
  
  > 1 │ foo = bar;
      │ ^^^
    2 │ function foo() { };
    3 │ 
  
  ℹ Reassignment happens here because the function declaration is hoisted.
  
  ℹ Use a local variable instead.
  

[foo] = bar;
function foo() { };

correctness/noFunctionAssign.js:2:10 lint/correctness/noFunctionAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Do not reassign a function declaration.
  
    1 │ [foo] = bar;
  > 2 │ function foo() { };
      │          ^^^
    3 │ 
  
  ℹ Reassigned here.
  
  > 1 │ [foo] = bar;
      │  ^^^
    2 │ function foo() { };
    3 │ 
  
  ℹ Reassignment happens here because the function declaration is hoisted.
  
  ℹ Use a local variable instead.
  

({ x: foo = 0 } = bar);
function foo() { };

correctness/noFunctionAssign.js:2:10 lint/correctness/noFunctionAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Do not reassign a function declaration.
  
    1 │ ({ x: foo = 0 } = bar);
  > 2 │ function foo() { };
      │          ^^^
    3 │ 
  
  ℹ Reassigned here.
  
  > 1 │ ({ x: foo = 0 } = bar);
      │       ^^^
    2 │ function foo() { };
    3 │ 
  
  ℹ Reassignment happens here because the function declaration is hoisted.
  
  ℹ Use a local variable instead.
  

function foo() {
    [foo] = bar;
 }

correctness/noFunctionAssign.js:1:10 lint/correctness/noFunctionAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Do not reassign a function declaration.
  
  > 1 │ function foo() {
      │          ^^^
    2 │     [foo] = bar;
    3 │  }
  
  ℹ Reassigned here.
  
    1 │ function foo() {
  > 2 │     [foo] = bar;
      │      ^^^
    3 │  }
    4 │ 
  
  ℹ Use a local variable instead.
  

(function () {
    ({ x: foo = 0 } = bar);
    function foo() { };
 })();

correctness/noFunctionAssign.js:3:14 lint/correctness/noFunctionAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Do not reassign a function declaration.
  
    1 │ (function () {
    2 │     ({ x: foo = 0 } = bar);
  > 3 │     function foo() { };
      │              ^^^
    4 │  })();
    5 │ 
  
  ℹ Reassigned here.
  
    1 │ (function () {
  > 2 │     ({ x: foo = 0 } = bar);
      │           ^^^
    3 │     function foo() { };
    4 │  })();
  
  ℹ Reassignment happens here because the function declaration is hoisted.
  
  ℹ Use a local variable instead.
  

Valid

function foo() {
    var foo = bar;
 }

function foo(foo) {
    foo = bar;
 }

function foo() {
    var foo;
    foo = bar;
 }

var foo = () => {};
foo = bar;

var foo = function() {};
foo = bar;

var foo = function() {
    foo = bar;
 };

import bar from 'bar';
function foo() {
    var foo = bar;
}