raise error if strftime called on out-of-python-range timestamps

Author: MarcoGorelli

pandas/_libs/tslibs/timestamps.pyx

@@ -1409,7 +1409,15 @@ class Timestamp(_Timestamp):
         >>> ts.strftime('%Y-%m-%d %X')
         '2020-03-14 15:32:52'
         """
-        return datetime.strftime(self, format)
+        try:
+            return self.to_pydatetime().strftime(format)
+        except ValueError as err:
+            raise ValueError(
+                "strftime not yet supported on Timestamps which "
+                "are outside the range of Python's standard library. "
+                "For now, please call the components you need (such as `.year` "
+                "and `.month`) and construct your string from there."
+            )
 
     # Issue 25016.
     @classmethod

pandas/tests/scalar/timestamp/test_timestamp.py

@@ -1104,3 +1104,15 @@ def test_utctimetuple():
     result = ts.utctimetuple()
     expected = time.struct_time((2000, 1, 1, 0, 0, 0, 5, 1, 0))
     assert result == expected
+
+
+def test_negative_dates():
+    # https://github.com/pandas-dev/pandas/issues/50787
+    ts = Timestamp("-2000-01-01")
+    msg = (
+        "^strftime not yet supported on Timestamps which are outside the range of "
+        "Python's standard library. For now, please call the components you need "
+        r"\(such as `.year` and `.month`\) and construct your string from there.$"
+    )
+    with pytest.raises(ValueError, match=msg):
+        ts.strftime("%Y")