update

Author: TomAugspurger

doc/source/install.rst

@@ -286,6 +286,7 @@ psycopg2                                     PostgreSQL engine for sqlalchemy
 pyarrow                   0.9.0              Parquet and feather reading / writing
 pymysql                                      MySQL engine for sqlalchemy
 pyreadstat                                   SPSS files (.sav) reading
+pytables                  3.4.2              HDF5 reading / writing
 qtpy                                         Clipboard I/O
 s3fs                      0.0.8              Amazon S3 access
 xarray                    0.8.2              pandas-like API for N-dimensional data

pandas/compat/_optional.py

@@ -19,6 +19,7 @@
     "s3fs": "0.0.8",
     "scipy": "0.19.0",
     "sqlalchemy": "1.1.4",
+    "tables": "3.4.2",
     "xarray": "0.8.2",
     "xlrd": "1.1.0",
     "xlwt": "1.2.0",

pandas/io/pytables.py

@@ -19,6 +19,7 @@
 
 from pandas._libs import lib, writers as libwriters
 from pandas._libs.tslibs import timezones
+from pandas.compat._optional import import_optional_dependency
 from pandas.errors import PerformanceWarning
 
 from pandas.core.dtypes.common import (
@@ -448,11 +449,7 @@ def __init__(self, path, mode=None, complevel=None, complib=None,
         if 'format' in kwargs:
             raise ValueError('format is not a defined argument for HDFStore')
 
-        try:
-            import tables  # noqa
-        except ImportError as ex:  # pragma: no cover
-            raise ImportError('HDFStore requires PyTables, "{ex!s}" problem '
-                              'importing'.format(ex=ex))
+        tables = import_optional_dependency("tables")
 
         if complib is not None and complib not in tables.filters.all_complibs:
             raise ValueError(

pandas/tests/test_optional_dependency.py

@@ -4,7 +4,9 @@
 import pytest
 
 from pandas.compat._optional import VERSIONS, import_optional_dependency
+import pandas.util._test_decorators as td
 
+import pandas as pd
 import pandas.util.testing as tm
 
 
@@ -50,3 +52,11 @@ def test_no_version_raises():
 
     with pytest.raises(ImportError, match="Can't determine .* fakemodule"):
         import_optional_dependency(name)
+
+
+@td.skip_if_installed("tables")
+def test_pytables_raises():
+    df = pd.DataFrame({"A": [1, 2]})
+    with pytest.raises(ImportError, match="tables"):
+        with tm.ensure_clean("foo.h5") as path:
+            df.to_hdf(path, "df")

pandas/util/_test_decorators.py

@@ -99,6 +99,23 @@ def _skip_if_no_scipy():
                 safe_import('scipy.signal'))
 
 
+def skip_if_installed(
+    package: str,
+) -> MarkDecorator:
+    """
+    Skip a test if a package is installed.
+
+    Parameters
+    ----------
+    package : str
+        The name of the package.
+    """
+    return pytest.mark.skipif(
+        safe_import(package),
+        reason="Skipping because {} is installed.".format(package)
+    )
+
+
 def skip_if_no(
     package: str,
     min_version: Optional[str] = None