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handle-throwing-invocations

added in: 1.19.0
warning
Pro+

Warns when an invocation's declaration is annotated with @Throws() but the potential exception is not handled.

info

To use the @Throws() annotation, install the dart-code-metrics-annotations package.

And to get warnings for missing or unnecessary @Throws() annotations, enable the prefer-correct-throws rule.

Example​

❌ Bad:

void fn() {
  someFunction(); // LINT: This invocation is annotated with @Throws and can throw an exception. Try handing this exception or annotating the outer declaration with @Throws.

  try {
    someFunction(); // LINT: This invocation is annotated with @Throws and can throw an exception. Try handing this exception or annotating the outer declaration with @Throws.
  } on Exception catch (_) {}

  @Throws({IndexError})
  final local = someFunction;

  local(); // LINT: This invocation is annotated with @Throws and can throw an exception. Try handing this exception or annotating the outer declaration with @Throws.
}

@Throws({TypeError})
void nestedIncorrect() {
  someFunction(); // LINT: This invocation is annotated with @Throws and can throw an exception. Try handing this exception or annotating the outer declaration with @Throws.
}

void fn(@Throws() void Function() callback) {
  callback(); // LINT: This invocation is annotated with @Throws and can throw an exception. Try handing this exception or annotating the outer declaration with @Throws.
}

@Throws({IndexError})
void someFunction() {
  ...
}

✅ Good:

void fn() {
  try {
    someFunction();
  } on IndexError catch (_) {}

  try {
    someFunction();
  } catch (_) {}
}

@Throws()
void nested() {
  someFunction();
}

void fn(@Throws() void Function() callback) {
  try {
    callback();
  } catch (_) {}
}

@Throws({IndexError})
void someFunction() {
  ...
}

Additional Resources​