REF: remove _get_join_target (#43788)

Author: jbrockmendel

pandas/core/indexes/base.py

@@ -315,17 +315,17 @@ class Index(IndexOpsMixin, PandasObject):
     @final
     def _left_indexer_unique(self: _IndexT, other: _IndexT) -> npt.NDArray[np.intp]:
         # Caller is responsible for ensuring other.dtype == self.dtype
-        sv = self._get_join_target()
-        ov = other._get_join_target()
+        sv = self._get_engine_target()
+        ov = other._get_engine_target()
         return libjoin.left_join_indexer_unique(sv, ov)
 
     @final
     def _left_indexer(
         self: _IndexT, other: _IndexT
     ) -> tuple[ArrayLike, npt.NDArray[np.intp], npt.NDArray[np.intp]]:
         # Caller is responsible for ensuring other.dtype == self.dtype
-        sv = self._get_join_target()
-        ov = other._get_join_target()
+        sv = self._get_engine_target()
+        ov = other._get_engine_target()
         joined_ndarray, lidx, ridx = libjoin.left_join_indexer(sv, ov)
         joined = self._from_join_target(joined_ndarray)
         return joined, lidx, ridx
@@ -335,8 +335,8 @@ def _inner_indexer(
         self: _IndexT, other: _IndexT
     ) -> tuple[ArrayLike, npt.NDArray[np.intp], npt.NDArray[np.intp]]:
         # Caller is responsible for ensuring other.dtype == self.dtype
-        sv = self._get_join_target()
-        ov = other._get_join_target()
+        sv = self._get_engine_target()
+        ov = other._get_engine_target()
         joined_ndarray, lidx, ridx = libjoin.inner_join_indexer(sv, ov)
         joined = self._from_join_target(joined_ndarray)
         return joined, lidx, ridx
@@ -346,8 +346,8 @@ def _outer_indexer(
         self: _IndexT, other: _IndexT
     ) -> tuple[ArrayLike, npt.NDArray[np.intp], npt.NDArray[np.intp]]:
         # Caller is responsible for ensuring other.dtype == self.dtype
-        sv = self._get_join_target()
-        ov = other._get_join_target()
+        sv = self._get_engine_target()
+        ov = other._get_engine_target()
         joined_ndarray, lidx, ridx = libjoin.outer_join_indexer(sv, ov)
         joined = self._from_join_target(joined_ndarray)
         return joined, lidx, ridx
@@ -894,6 +894,8 @@ def ravel(self, order="C"):
             # Item "ndarray[Any, Any]" of "Union[ExtensionArray, ndarray[Any, Any]]"
             # has no attribute "_ndarray"
             values = self._data._ndarray  # type: ignore[union-attr]
+        elif is_interval_dtype(self.dtype):
+            values = np.asarray(self._data)
         else:
             values = self._get_engine_target()
         return values.ravel(order=order)
@@ -4618,12 +4620,6 @@ def _get_engine_target(self) -> np.ndarray:
         # ndarray]", expected "ndarray")
         return self._values  # type: ignore[return-value]
 
-    def _get_join_target(self) -> np.ndarray:
-        """
-        Get the ndarray that we will pass to libjoin functions.
-        """
-        return self._get_engine_target()
-
     def _from_join_target(self, result: np.ndarray) -> ArrayLike:
         """
         Cast the ndarray returned from one of the libjoin.foo_indexer functions

pandas/core/indexes/extension.py

@@ -243,9 +243,6 @@ def searchsorted(
 
     # ---------------------------------------------------------------------
 
-    def _get_engine_target(self) -> np.ndarray:
-        return np.asarray(self._data)
-
     def delete(self, loc):
         """
         Make new Index with passed location(-s) deleted

pandas/core/indexes/interval.py

@@ -892,11 +892,14 @@ def _is_all_dates(self) -> bool:
         """
         return False
 
-    def _get_join_target(self) -> np.ndarray:
+    def _get_engine_target(self) -> np.ndarray:
         # Note: we _could_ use libjoin functions by either casting to object
         #  dtype or constructing tuples (faster than constructing Intervals)
         #  but the libjoin fastpaths are no longer fast in these cases.
-        raise NotImplementedError("IntervalIndex does not use libjoin fastpaths")
+        raise NotImplementedError(
+            "IntervalIndex does not use libjoin fastpaths or pass values to "
+            "IndexEngine objects"
+        )
 
     def _from_join_target(self, result):
         raise NotImplementedError("IntervalIndex does not use libjoin fastpaths")