From e38e854f7023cc70c71b3ccf1ff35e9d73448671 Mon Sep 17 00:00:00 2001
From: Matthew Roeschke <10647082+mroeschke@users.noreply.github.com>
Date: Mon, 22 Apr 2024 10:43:11 -0700
Subject: [PATCH] REF: Defer creating Index._engine until needed

---
 pandas/core/frame.py        | 3 +--
 pandas/core/indexes/base.py | 3 ++-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 0185ca8241617..91b18dbe0bb1f 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -4012,7 +4012,6 @@ def _get_value(self, index, col, takeable: bool = False) -> Scalar:
             return series._values[index]
 
         series = self._get_item(col)
-        engine = self.index._engine
 
         if not isinstance(self.index, MultiIndex):
             # CategoricalIndex: Trying to use the engine fastpath may give incorrect
@@ -4023,7 +4022,7 @@ def _get_value(self, index, col, takeable: bool = False) -> Scalar:
 
         # For MultiIndex going through engine effectively restricts us to
         #  same-length tuples; see test_get_set_value_no_partial_indexing
-        loc = engine.get_loc(index)
+        loc = self.index._engine.get_loc(index)
         return series._values[loc]
 
     def isetitem(self, loc, value) -> None:
diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 69f916bb3f769..9036123f3cb67 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -832,7 +832,8 @@ def _reset_identity(self) -> None:
 
     @final
     def _cleanup(self) -> None:
-        self._engine.clear_mapping()
+        if "_engine" in self._cache:
+            self._engine.clear_mapping()
 
     @cache_readonly
     def _engine(