private static boolean isNotZeroCheck(@NotNull PsiStatement statement, @NotNull PsiVariable last) {
    PsiIfStatement ifStatement = tryCast(statement, PsiIfStatement.class);
    if (ifStatement == null || ifStatement.getElseBranch() != null) return false;
    PsiBinaryExpression binaryExpression = tryCast(ifStatement.getCondition(), PsiBinaryExpression.class);
    if (binaryExpression == null) return false;
    if (!ExpressionUtils.isReferenceTo(ExpressionUtils.getValueComparedWithZero(binaryExpression, JavaTokenType.NE), last)) return false;
    PsiStatement thenStmt = ControlFlowUtils.stripBraces(ifStatement.getThenBranch());
    if (!(thenStmt instanceof PsiReturnStatement)) return false;
    return ExpressionUtils.isReferenceTo(((PsiReturnStatement)thenStmt).getReturnValue(), last);
  }
private static boolean isNotZeroCheck(@NotNull PsiStatement statement, @NotNull PsiVariable last)