COMPAT: numpy test warnings (pandas-dev#30345)

Author: nschloe

pandas/tests/arrays/test_integer.py

@@ -935,6 +935,8 @@ def test_astype_nansafe():
 
 
 @pytest.mark.parametrize("ufunc", [np.abs, np.sign])
+# np.sign emits a warning with nans, <https://github.com/numpy/numpy/issues/15127>
+@pytest.mark.filterwarnings("ignore:invalid value encountered in sign")
 def test_ufuncs_single_int(ufunc):
     a = integer_array([1, 2, -3, np.nan])
     result = ufunc(a)

pandas/tests/plotting/test_datetimelike.py

@@ -43,7 +43,13 @@ def setup_method(self, method):
     def teardown_method(self, method):
         tm.close()
 
+    # Ignore warning
+    # ```
+    # Converting to PeriodArray/Index representation will drop timezone information.
+    # ```
+    # which occurs for UTC-like timezones.
     @pytest.mark.slow
+    @pytest.mark.filterwarnings("ignore:msg:UserWarning")
     def test_ts_plot_with_tz(self, tz_aware_fixture):
         # GH2877, GH17173
         tz = tz_aware_fixture