BUG: Handle NaN values for datetime and timedelta dtypes in BlockManager

Author: fbourgey

pandas/core/internals/managers.py

@@ -1800,6 +1800,8 @@ def as_array(
                 arr = np.asarray(blk.values, dtype=dtype)
             else:
                 arr = np.array(blk.values, dtype=dtype, copy=copy)
+            if passed_nan and blk.dtype.kind in ["m", "M"]:
+                arr[isna(blk.values)] = na_value
 
             if not copy:
                 arr = arr.view()
@@ -1865,6 +1867,8 @@ def _interleave(
             else:
                 arr = blk.get_values(dtype)
             result[rl.indexer] = arr
+            if na_value is not lib.no_default and blk.dtype.kind in ["m", "M"]:
+                result[rl.indexer][isna(arr)] = na_value
             itemmask[rl.indexer] = 1
 
         if not itemmask.all():