report-message-format.md

Enforce a consistent format for rule report messages (eslint-plugin/report-message-format)

It is sometimes desirable to maintain consistent formatting for all report messages. For example, you might want to mandate that all report messages begin with a capital letter and end with a period.

Rule Details

This rule aims to enforce a consistent format for rule report messages.

Options

This rule has a string option. The string should be a regular expression that all report messages must match.

For example, in order to mandate that all report messages begin with a capital letter and end with a period, you can use the following configuration:

{
  "rules": {
    "eslint-plugin/report-message-format": ["error", "^[A-Z].*\\.$"]
  },
  "plugins": ["eslint-plugin"]
}

Note that since this rule uses static analysis and does not actually run your code, it will attempt to match report messages before placeholders are inserted.

Examples of incorrect code for this rule:

/* eslint eslint-plugin/report-message-format: ["error", "^[A-Z].*\\.$"] */

module.exports = {
  meta: {},
  create(context) {
    context.report(node, 'this message does not match the regular expression.');

    context.report(node, 'Neither does this one');

    context.report(
      node,
      'This will get reported, regardless of the value of the {{placeholder}}',
      { placeholder: foo },
    );
  },
};

Examples of correct code for this rule:

module.exports = {
  meta: {},
  create(context) {
    context.report(node, 'This message matches the regular expression.');

    context.report(node, 'So does this one.');
  },
};

When Not To Use It

If you don't want to enforce consistent formatting for your report messages, you can turn off this rule.