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noClassAssign (since v1.0.0)

Diagnostic Category: lint/suspicious/noClassAssign

Sources:

Disallow reassigning class members.

A class declaration creates a variable that we can modify, however, the modification is a mistake in most cases.

Examples

Section titled Examples

Invalid

Section titled Invalid
class A {}
A = 0;
suspicious/noClassAssign.js:2:1 lint/suspicious/noClassAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ 'A' is a class.
  
    1 │ class A {}
  > 2 │ A = 0;
      │ ^
    3 │ 
  
  ℹ 'A' is defined here.
  
  > 1 │ class A {}
      │       ^
    2 │ A = 0;
    3 │ 
  

A = 0;
class A {}
suspicious/noClassAssign.js:1:1 lint/suspicious/noClassAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ 'A' is a class.
  
  > 1 │ A = 0;
      │ ^
    2 │ class A {}
    3 │ 
  
  ℹ 'A' is defined here.
  
    1 │ A = 0;
  > 2 │ class A {}
      │       ^
    3 │ 
  

class A {
  b() {
    A = 0;
  }
}
suspicious/noClassAssign.js:3:3 lint/suspicious/noClassAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ 'A' is a class.
  
    1 │ class A {
    2 │ 	b() {
  > 3 │ 		A = 0;
      │ 		^
    4 │ 	}
    5 │ }
  
  ℹ 'A' is defined here.
  
  > 1 │ class A {
      │       ^
    2 │ 	b() {
    3 │ 		A = 0;
  

let A = class A {
  b() {
    A = 0;
    // `let A` is shadowed by the class name.
  }
}
suspicious/noClassAssign.js:3:3 lint/suspicious/noClassAssign ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ 'A' is a class.
  
    1 │ let A = class A {
    2 │ 	b() {
  > 3 │ 		A = 0;
      │ 		^
    4 │ 		// `let A` is shadowed by the class name.
    5 │ 	}
  
  ℹ 'A' is defined here.
  
  > 1 │ let A = class A {
      │               ^
    2 │ 	b() {
    3 │ 		A = 0;

Valid

Section titled Valid
let A = class A {}
A = 0; // A is a variable.
let A = class {
    b() {
        A = 0; // A is a variable.
    }
}
class A {
  b(A) {
    A = 0; // A is a parameter.
  }
}
Section titled Related links