ignore arrow warnings and foward declare arrow

include/xlnt/utils/xlntarrow.hpp

@@ -1,12 +1,15 @@
 #include <iostream>
-#include <arrow/api.h>
 #include <xlnt/xlnt_config.hpp>
 
+namespace arrow {
+class Table;
+}
+
 namespace xlnt {
 namespace arrow {
 
 void XLNT_API xlsx2arrow(std::istream &s, ::arrow::Table &table);
 void XLNT_API arrow2xlsx(const ::arrow::Table &table, std::ostream &s);
 
-}
-}
+} // namespace arrow
+} // namespace xlnt

source/utils/xlntarrow.cpp

@@ -1,3 +1,10 @@
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wsign-conversion"
+#pragma clang diagnostic ignored "-Wswitch-enum"
+#pragma clang diagnostic ignored "-Wshadow"
+#include <arrow/api.h>
+#pragma clang diagnostic pop
+
 #include <xlnt/cell/cell.hpp>
 #include <xlnt/cell/cell_reference.hpp>
 #include <xlnt/workbook/streaming_workbook_reader.hpp>

xlntpyarrow/xlntpyarrow.cpp

@@ -1,9 +1,12 @@
 #include <iostream>
 #include <memory>
 #include <vector>
-#include <xlnt/utils/xlntarrow.hpp>
+
+#include <arrow/api.h>
+#include <Python.h> // must be included after Arrow
+
 #include <python_streambuf.hpp>
-#include <Python.h>
+#include <xlnt/utils/xlntarrow.hpp>
 
 PyObject *xlsx2arrow(PyObject *file)
 {