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Severity: warning
Category: lint
Stage: Stage 3

Description

The debugger statement pauses execution in a JavaScript debugger. It is a development-only tool and must not appear in committed source code. When the code is deployed without a debugger attached the debugger statement is silently ignored, but it indicates an incomplete cleanup of a debugging session and may cause unexpected pauses in environments where a debugger is attached (e.g., browser DevTools left open, Node.js --inspect flag).

The lint pass flags every debugger statement unconditionally, regardless of the surrounding context (inside conditionals, dead branches, or test files).

Example

// ✗ lint warning
function processOrder(order: Order) {
  debugger                  // SJS-L005
  const total = order.items.reduce((s, i) => s + i.price, 0)
  return total
}

Fix

Remove the debugger statement:

// ✓ correct
function processOrder(order: Order) {
  const total = order.items.reduce((s, i) => s + i.price, 0)
  return total
}

Use conditional breakpoints in your debugger tooling, or structured logging, rather than embedding debugger statements in source.

Auto-fix

This diagnostic is auto-fixable. Running superjs fix removes every debugger statement (the statement and its trailing newline are deleted).

Configuration

Configurable in superjs.config.json:

{
  "lint": {
    "L005": "error" | "warn" | "off"
  }
}

Default: "warn" in standard mode, "error" in --strict mode.

Related codes

  • SJS-L001 — prefer const — let binding is never reassigned
Documentation