eslint/max-depth Pedantic

What it does

Enforce a maximum depth that blocks can be nested. This rule helps to limit the complexity of nested blocks, improving readability and maintainability by ensuring that code does not become too deeply nested.

Why is this bad?

Many developers consider code difficult to read if blocks are nested beyond a certain depth. Excessive nesting can make it harder to follow the flow of the code, increasing cognitive load and making maintenance more error-prone. By enforcing a maximum block depth, this rule encourages cleaner, more readable code.

Examples

Examples of incorrect code for this rule with the default { "max": 3 } option:

function foo() {
  for (;;) { // Nested 1 deep
    while (true) { // Nested 2 deep
      if (true) { // Nested 3 deep
        if (true) { // Nested 4 deep }
      }
    }
  }
}

Examples of correct code for this rule with the default { "max": 3 } option:

function foo() {
  for (;;) { // Nested 1 deep
    while (true) { // Nested 2 deep
      if (true) { // Nested 3 deep }
    }
  }
}

Note that class static blocks do not count as nested blocks, and that the depth in them is calculated separately from the enclosing context.

Example:

function foo() {
  if (true) { // Nested 1 deep
    class C {
      static {
        if (true) { // Nested 1 deep
          if (true) { // Nested 2 deep }
        }
      }
    }
  }
}

Options

max

{ type: number, default: 4 }

The max enforces a maximum depth that blocks can be nested

Example:

"eslint/max-depth": ["error", 4]

"eslint/max-depth": [
  "error",
  {
    max: 4
  }
]

How to use

To enable this rule in the CLI or using the config file, you can use:

CLI

oxlint --deny max-depth

Config (.oxlintrc.json)

{
  "rules": {
    "max-depth": "error"
  }
}

References

• Rule Source