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require-break

Requires that each non-fallthrough case of a switch statement has a break statement.

Rule Details​

The no-fallthrough core ESLint rule helps to ensure that switch statements do not accidentally "fall through", which is a common mistake. It does this by ensuring that you put a break statement (or a return/throw) in every non-empty switch case.

However, it does not enforce a break statement on the final case. This makes sense, because there is nothing that the final case could ever fallthrough to. With that said, it can still be desirable to enforce a break statement for the final case. Doing this makes switch arms look more consistent, makes switch arms more resilient to reorganization, and reduces Git noise when a new switch case is added at the bottom. (This is similar to the benefits provided by trailing commas.)

This rule enforces break statements on the final case.

Note that this rule will still apply even if the final case is a default case, and this is intentional. Assuming that default cases are always at the bottom of a switch statement (using the default-case-last rule), default cases are distinct from other case statements in that they would not ever need to be reorganized or have something added underneath. So, the reasons for wanting a break statement in a default case are less intuitive. First, having "empty" default cases are sometimes required in order to satisfy the @typescript-eslint/switch-exhaustiveness-check rule (e.g. when you only want to define behavior for 2 out of 10 enum members). In these cases, a break statement is useful to order to avoid triggering the no-empty rule and to avoid the appearance of the arm being unfinished. Thus, since break statements might be desired for otherwise-empty default cases, it can make sense to enforce them in every default case across a codebase for consistency.

// Bad
switch (foo) {
  case 1: {
    doSomething1();
    break;
  }

  case 2: {
    doSomething2();
  }
}

// Good
switch (foo) {
  case 1: {
    doSomething1();
    break;
  }

  case 2: {
    doSomething2();
    break;
  }
}

Options and Defaults​

{
  "rules": {
    "complete/require-break": "error"
  }
}

This rule is not configurable.

Resources​