From 12fd316de829b994d6e3d1fc14c59d8e8bf34500 Mon Sep 17 00:00:00 2001
From: Kendall Masse <kendall.masse@gmail.com>
Date: Tue, 12 Mar 2019 16:45:23 -0400
Subject: [PATCH] BUG: Fix error in replace with strings that are large numbers
 (#25616) (#25644)

---
 doc/source/whatsnew/v0.24.2.rst     |  2 ++
 pandas/core/internals/blocks.py     |  4 ++--
 pandas/tests/series/test_replace.py | 14 ++++++++++++++
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/doc/source/whatsnew/v0.24.2.rst b/doc/source/whatsnew/v0.24.2.rst
index c07959c758780..5b5c9c78d10da 100644
--- a/doc/source/whatsnew/v0.24.2.rst
+++ b/doc/source/whatsnew/v0.24.2.rst
@@ -33,6 +33,7 @@ Fixed Regressions
 - Fixed regression in :class:`Categorical`, where constructing it from a categorical ``Series`` and an explicit ``categories=`` that differed from that in the ``Series`` created an invalid object which could trigger segfaults. (:issue:`25318`)
 - Fixed regression in :func:`to_timedelta` losing precision when converting floating data to ``Timedelta`` data (:issue:`25077`).
 - Fixed pip installing from source into an environment without NumPy (:issue:`25193`)
+- Fixed regression in :meth:`DataFrame.replace` where large strings of numbers would be coerced into ``int64``, causing an ``OverflowError`` (:issue:`25616`)
 - Fixed regression in :func:`factorize` when passing a custom ``na_sentinel`` value with ``sort=True`` (:issue:`25409`).
 - Fixed regression in :meth:`DataFrame.to_csv` writing duplicate line endings with gzip compress (:issue:`25311`)
 
@@ -90,6 +91,7 @@ A total of 25 people contributed patches to this release. People with a "+" by t
 * Joris Van den Bossche
 * Josh
 * Justin Zheng
+* Kendall Masse
 * Matthew Roeschke
 * Max Bolingbroke +
 * rbenes +
diff --git a/pandas/core/internals/blocks.py b/pandas/core/internals/blocks.py
index ada663556899b..0375f782badcc 100644
--- a/pandas/core/internals/blocks.py
+++ b/pandas/core/internals/blocks.py
@@ -1079,7 +1079,7 @@ def coerce_to_target_dtype(self, other):
 
         try:
             return self.astype(dtype)
-        except (ValueError, TypeError):
+        except (ValueError, TypeError, OverflowError):
             pass
 
         return self.astype(object)
@@ -3210,7 +3210,7 @@ def _putmask_smart(v, m, n):
                 nv = v.copy()
                 nv[m] = nn_at
                 return nv
-    except (ValueError, IndexError, TypeError):
+    except (ValueError, IndexError, TypeError, OverflowError):
         pass
 
     n = np.asarray(n)
diff --git a/pandas/tests/series/test_replace.py b/pandas/tests/series/test_replace.py
index 40b28047080da..2e7b746f6c9f2 100644
--- a/pandas/tests/series/test_replace.py
+++ b/pandas/tests/series/test_replace.py
@@ -280,3 +280,17 @@ def test_replace_mixed_types_with_string(self):
         result = s.replace([2, '4'], np.nan)
         expected = pd.Series([1, np.nan, 3, np.nan, 4, 5])
         tm.assert_series_equal(expected, result)
+
+    def test_replace_with_no_overflowerror(self):
+        # GH 25616
+        # casts to object without Exception from OverflowError
+        s = pd.Series([0, 1, 2, 3, 4])
+        result = s.replace([3], ['100000000000000000000'])
+        expected = pd.Series([0, 1, 2, '100000000000000000000', 4])
+        tm.assert_series_equal(result, expected)
+
+        s = pd.Series([0, '100000000000000000000',
+                      '100000000000000000001'])
+        result = s.replace(['100000000000000000000'], [1])
+        expected = pd.Series([0, 1, '100000000000000000001'])
+        tm.assert_series_equal(result, expected)