📎 Implement noMagicNumbers - eslint/no-magic-numbers, typescript-eslint/no-magic-numbers

[Conaclos]

Description

Implement eslint/no-magic-numbers and typescript-eslint/no-magic-numbers.

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See the related discussion for context.

The ESLint rule has many options.
I suggest implementing a single option ignoreIntegers (See the Options section) for the time being.

Here are the exceptions we should bake in:

• ignore assignment to constant-like variables, i.e. const, var, and static class properties

  const A = 0.25;
  const B = 0.25;
  class Foo {
    static C = 0.5;
  }

• Ignore common numbers
  We should always ignore 0/0n/0., and maybe 2/2n, 1/1n, and -1/-1n.

  -1; 0; 1; -1n; 0n; 1n;

  Should we ignore more integers?

• Ignore integer indexing (corresponds setting ESLints' ignoreArrayIndexes and ignoreTypeIndexes to true)

  arr[10];
  type Foo = Bar[10];
  type Baz = Parameters<Foo>[10];

• Ignore integer Enum values (corresponds setting ESLint's ignoreEnums to true)

  enum E {
    A = 3;
    B = 4;
  }

• ignore numeric types (corresponds setting ESLint's ignoreNumericLiteralTypes to true)

  type SmallPrimes = 2 | 3 | 5 | 7 | 11;
  function f(x: 100): 100 { return x }

• Ignore integer binary operations

  const x = 1 << 4;
  const x = a & 0xff;
  const x = a | 0x0f;

• Others?

Options

We could introduce an ignoreIntegers option (turned off by default).
When the option is set to true, all integers values are ignored:

1795;
1795n;

[Conaclos]

@fellipeutaka Could you add a comment on this task. I am not able to assign you to the task if you don't participate here.

[fellipeutaka]

@fellipeutaka Could you add a comment on this task. I am not able to assign you to the task if you don't participate here.

Oh, sorry. I'm ready to contribute to this task :)

[Conaclos]

Oh, sorry. I'm ready to contribute to this task :)

No problem. I was not aware of this limitation on GitHub ^^
I guess this is to avoid assigning a wrong person.