Rule: max-line-length

Requires lines to be under a certain max length.

Rationale

Limiting the length of a line of code improves code readability. It also makes comparing code side-by-side easier and improves compatibility with various editors, IDEs, and diff viewers.

Config

It can take one argument, which can be any of the following:

• integer indicating maximum length of lines.
• object with keys:
  • limit - number greater than 0 defining the max line length
  • ignore-pattern - string defining ignore pattern for this rule, being parsed by new RegExp(). For example:
    • // pattern will ignore all in-line comments.
    • ^import pattern will ignore all import statements.
    • ^export {(.*?)} pattern will ignore all multiple export statements.
    • class [a-zA-Z]+ implements pattern will ignore all class declarations implementing interfaces.
    • ^import |^export {(.*?)}|class [a-zA-Z]+ implements |// pattern will ignore all the cases listed above.
  • check-strings - determines if strings should be checked, false by default.
  • check-regex - determines if regular expressions should be checked, false by default.

Config examples

"max-line-length": [true, 120]

"max-line-length": [
  true,
  {
    "limit": 120,
    "ignore-pattern": "^import |^export {(.*?)}",
    "check-strings": true,
    "check-regex": true
  }
]

Schema

{
  "type": "array",
  "items": {
    "oneOf": [
      {
        "type": "number"
      },
      {
        "type": "object",
        "properties": {
          "limit": {
            "type": "number"
          },
          "ignore-pattern": {
            "type": "string"
          },
          "check-strings": {
            "type": "boolean"
          },
          "check-regex": {
            "type": "boolean"
          }
        },
        "additionalProperties": false
      }
    ]
  },
  "minLength": 1,
  "maxLength": 2
}