close_sinks

Close instances of dart:core Sink.

DO invoke close on instances of dart:core Sink.

Closing instances of Sink prevents memory leaks and unexpected behavior.

BAD:

class A {
  IOSink _sinkA;
  void init(filename) {
    _sinkA = File(filename).openWrite(); // LINT
  }
}

BAD:

void someFunction() {
  IOSink _sinkF; // LINT
}

GOOD:

class B {
  IOSink _sinkB;
  void init(filename) {
    _sinkB = File(filename).openWrite(); // OK
  }
​
  void dispose(filename) {
    _sinkB.close();
  }
}

GOOD:

void someFunctionOK() {
  IOSink _sinkFOK; // OK
  _sinkFOK.close();
}

Known limitations

This rule does not track all patterns of Sink instantiations and closures. See sdk#57882 for more information.

To enable the close_sinks rule, add close_sinks under linter > rules in your analysis_options.yaml file:

linter:
  rules:
    - close_sinks

If you're instead using the YAML map syntax to configure linter rules, add close_sinks: true under linter > rules:

linter:
  rules:
    close_sinks: true