eslint/docs/rules/no-useless-catch.md

   1 # Disallow unnecessary catch clauses (no-useless-catch)
   2
   3 A `catch` clause that only rethrows the original error is redundant, and has no effect on the runtime behavior of the program. These redundant clauses can be a source of confusion and code bloat, so it's better to disallow these unnecessary `catch` clauses.
   4
   5 ## Rule Details
   6
   7 This rule reports `catch` clauses that only `throw` the caught error.
   8
   9 Examples of **incorrect** code for this rule:
  10
  11 ```js
  12 /*eslint no-useless-catch: "error"*/
  13
  14 try {
  15   doSomethingThatMightThrow();
  16 } catch (e) {
  17   throw e;
  18 }
  19
  20 try {
  21   doSomethingThatMightThrow();
  22 } catch (e) {
  23   throw e;
  24 } finally {
  25   cleanUp();
  26 }
  27 ```
  28
  29 Examples of **correct** code for this rule:
  30
  31 ```js
  32 /*eslint no-useless-catch: "error"*/
  33
  34 try {
  35   doSomethingThatMightThrow();
  36 } catch (e) {
  37   doSomethingBeforeRethrow();
  38   throw e;
  39 }
  40
  41 try {
  42   doSomethingThatMightThrow();
  43 } catch (e) {
  44   handleError(e);
  45 }
  46
  47 try {
  48   doSomethingThatMightThrow();
  49 } finally {
  50   cleanUp();
  51 }
  52 ```
  53
  54 ## When Not To Use It
  55
  56 If you don't want to be notified about unnecessary catch clauses, you can safely disable this rule.