bool isMountedCheck()

in lib/src/rules/use_build_context_synchronously.dart [187:262]
60 lines of code
22 McCabe index (conditional complexity)

  bool isMountedCheck(Statement statement, {bool positiveCheck = false}) {
    // This is intentionally naive.  Using a simple 'mounted' property check
    // as a signal plays nicely w/ unanticipated framework classes that provide
    // their own mounted checks.  The cost of this generality is the possibility
    // of false negatives.
    if (statement is IfStatement) {
      var condition = statement.condition;

      Expression check;
      if (condition is PrefixExpression) {
        if (positiveCheck && condition.isNot) {
          return false;
        }
        check = condition.operand;
      } else {
        check = condition;
      }

      bool checksMounted(Expression check) {
        if (check is BinaryExpression) {
          // (condition && context.mounted)
          if (positiveCheck) {
            if (check.isAnd) {
              return checksMounted(check.leftOperand) ||
                  checksMounted(check.rightOperand);
            }
          } else {
            // (condition || !mounted)
            if (check.isOr) {
              return checksMounted(check.leftOperand) ||
                  checksMounted(check.rightOperand);
            }
          }
        }

        // stateContext.mounted => mounted
        if (check is PrefixedIdentifier) {
          // ignore: parameter_assignments
          check = check.identifier;
        }
        if (check is SimpleIdentifier) {
          return check.name == 'mounted';
        }
        if (check is PrefixExpression) {
          // (condition || !mounted)
          if (!positiveCheck && check.isNot) {
            return checksMounted(check.operand);
          }
        }

        return false;
      }

      if (checksMounted(check)) {
        // In the positive case it's sufficient to know we're in a positively
        // guarded block.
        if (positiveCheck) {
          return true;
        }
        var then = statement.thenStatement;
        return terminatesControl(then);
      }
    } else if (statement is TryStatement) {
      var statements = statement.finallyBlock?.statements;
      if (statements == null) {
        return false;
      }
      for (var i = statements.length - 1; i >= 0; i--) {
        var s = statements[i];
        if (isMountedCheck(s)) {
          return true;
        }
      }
    }
    return false;
  }