From da0de55275f00f94eb84831f12e7dbe66c213734 Mon Sep 17 00:00:00 2001
From: Jon Mease <jonmmease@gmail.com>
Date: Sat, 30 Sep 2023 13:33:34 -0400
Subject: [PATCH] Fix encoding type inference for boolean columns when pyarrow
 is installed (#3210)

* Work around https://github.com/pandas-dev/pandas/issues/55332

* Only test boolean column with pandas >= 1.0.0
---
 altair/utils/core.py     | 6 ++++--
 tests/utils/test_core.py | 8 ++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/altair/utils/core.py b/altair/utils/core.py
index fa83665f5..45033572a 100644
--- a/altair/utils/core.py
+++ b/altair/utils/core.py
@@ -588,8 +588,10 @@ def parse_shorthand(
                     column = dfi.get_column_by_name(unescaped_field)
                     try:
                         attrs["type"] = infer_vegalite_type_for_dfi_column(column)
-                    except NotImplementedError:
-                        # Fall back to pandas-based inference
+                    except (NotImplementedError, AttributeError):
+                        # Fall back to pandas-based inference.
+                        # Note: The AttributeError catch is a workaround for
+                        # https://github.com/pandas-dev/pandas/issues/55332
                         if isinstance(data, pd.DataFrame):
                             attrs["type"] = infer_vegalite_type(data[unescaped_field])
                         else:
diff --git a/tests/utils/test_core.py b/tests/utils/test_core.py
index 75db18769..27cd3b7ee 100644
--- a/tests/utils/test_core.py
+++ b/tests/utils/test_core.py
@@ -1,4 +1,6 @@
 import types
+from packaging.version import Version
+from importlib.metadata import version as importlib_version
 
 import numpy as np
 import pandas as pd
@@ -16,6 +18,8 @@
 except ImportError:
     pa = None
 
+PANDAS_VERSION = Version(importlib_version("pandas"))
+
 
 FAKE_CHANNELS_MODULE = f'''
 """Fake channels module for utility tests."""
@@ -160,6 +164,10 @@ def check(s, data, **kwargs):
     check("month(z)", data, timeUnit="month", field="z", type="temporal")
     check("month(t)", data, timeUnit="month", field="t", type="temporal")
 
+    if PANDAS_VERSION >= Version("1.0.0"):
+        data["b"] = pd.Series([True, False, True, False, None], dtype="boolean")
+        check("b", data, field="b", type="nominal")
+
 
 @pytest.mark.skipif(pa is None, reason="pyarrow not installed")
 def test_parse_shorthand_for_arrow_timestamp():