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noConsole

Diagnostic Category: lint/suspicious/noConsole

Since: v1.6.0

Sources:

Disallow the use of console.

In a browser environment, it’s considered a best practice to log messages using console. Such messages are considered to be for debugging purposes and therefore not suitable to ship to the client. In general, calls using console should be stripped before being pushed to production.

Examples

Section titled Examples

Invalid

Section titled Invalid
console.error('hello world')
code-block.js:1:1 lint/suspicious/noConsole  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ Don’t use console.
  
  > 1 │ console.error(‘hello world’)
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ The use of console is often reserved for debugging.
  
  ℹ Unsafe fix: Remove console.
  
    1 │ console.error(‘hello·world’)
      │ ----------------------------

Options

Section titled Options

Use the options to explicitly allow a specific subset of console methods.

{
  "options": {
    "allow": ["assert", "error", "info", "warn"]
  }
}
console.error("error message"); // Allowed
console.warn("warning message"); // Allowed
console.info("info message"); // Allowed
console.log("log message");
console.assert(true, "explanation"); // Allowed
code-block.js:4:1 lint/suspicious/noConsole  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ Don’t use console.
  
    2 │ console.warn(“warning message”); // Allowed
    3 │ console.info(“info message”); // Allowed
  > 4 │ console.log(“log message”);
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    5 │ console.assert(true, “explanation”); // Allowed
    6 │ 
  
  ℹ The use of console is often reserved for debugging.
  
  ℹ Unsafe fix: Remove console.
  
    2 2 │   console.warn(“warning message”); // Allowed
    3 3 │   console.info(“info message”); // Allowed
    4   │ - console.log(“log·message”);
    5 4 │   console.assert(true, “explanation”); // Allowed
    6 5 │
Section titled Related links