ENH: Support for list of formats in pd.to_datetime() (pandas-dev#55226) pandas-dev#55698

Author: gusthavoMFS

pandas/core/tools/datetimes.py

@@ -1145,7 +1145,16 @@ def to_datetime(
         if not cache_array.empty:
             result = _convert_and_box_cache(argc, cache_array)
         else:
-            result = convert_listlike(argc, format)
+            #CHANGED HERE
+            if isinstance(format, (list, tuple)):
+                format = np.array(format, dtype="O")
+                return_list = [] # return list
+                for i, fmt in enumerate(format):
+                    return_temp = convert_listlike(argc[i],fmt) # return object of convert_listlike
+                    return_list.append(return_temp) # add in return list 
+                result = DatetimeIndex(return_list) # transformed object in datetimeindex
+            else:
+                result = convert_listlike(argc, format)
     else:
         result = convert_listlike(np.array([arg]), format)[0]
         if isinstance(arg, bool) and isinstance(result, np.bool_):

pandas/tests/tools/test_to_datetime.py

@@ -1090,7 +1090,20 @@ def test_to_datetime_now_with_format(self, format, expected_ds, string, attribut
             [expected_ds, getattr(Timestamp, attribute)()], dtype="datetime64[ns, UTC]"
         )
         assert (expected - result).max().total_seconds() < 1
-
+    
+    
+    def test_to_datetime_where_formart_is_list(self):
+        # https://github.com/pandas-dev/pandas/issues/55226
+        data = ['2023-10-12','2023-10-13 14:30:00']
+        all_formats = ['%Y-m-%d','%Y-%m-%d %H:%M:%S']
+        result = to_datetime(data,format=all_formats)
+        expect = DatetimeIndex(
+            [to_datetime(data[0],all_formats[0]),to_datetime(data[1],all_formats[1])], dtype="datetime64[ns]"
+        )
+        
+        tm.assert_index_equal(result,expect)
+    
+    
     @pytest.mark.parametrize(
         "dt", [np.datetime64("2000-01-01"), np.datetime64("2000-01-02")]
     )