implemented pyarrow timestamp support

Author: arthurlw

pandas/core/algorithms.py

@@ -59,6 +59,7 @@
 )
 from pandas.core.dtypes.concat import concat_compat
 from pandas.core.dtypes.dtypes import (
+    ArrowDtype,
     BaseMaskedDtype,
     CategoricalDtype,
     ExtensionDtype,
@@ -78,6 +79,7 @@
     na_value_for_dtype,
 )
 
+from pandas._libs.tslibs.timestamps import Timestamp
 from pandas.core.array_algos.take import take_nd
 from pandas.core.construction import (
     array as pd_array,
@@ -1691,6 +1693,14 @@ def map_array(
         if na_action == "ignore":
             mapper = mapper[mapper.index.notna()]
 
+        if isinstance(arr.dtype, ArrowDtype) and arr.dtype.name.startswith("timestamp"):
+            try:
+                # Convert elements to pandas.Timestamp (or datetime64[ns]) for dict lookup
+                arr = arr.astype("datetime64[ns]")
+            except Exception:
+                # fallback: safe, slow path
+                arr = np.array([Timestamp(x.as_py()) for x in arr])
+
         # Since values were input this means we came from either
         # a dict or a series and mapper should be an index
         indexer = mapper.index.get_indexer(arr)