TST: Remove bare pytest.raises

pandas/core/ops/array_ops.py

@@ -95,7 +95,9 @@ def masked_arith_op(x, y, op):
 
     else:
         if not is_scalar(y):
-            raise TypeError(type(y))
+            raise TypeError(
+                "Cannot broadcast np.ndarray with operand of type " + str(type(y))
+            )
 
         # mask is only meaningful for x
         result = np.empty(x.size, dtype=x.dtype)

pandas/tests/arithmetic/test_numeric.py

@@ -135,10 +135,11 @@ def test_div_td64arr(self, left, box_cls):
         result = right // left
         tm.assert_equal(result, expected)
 
-        with pytest.raises(TypeError):
+        msg = "Cannot divide"
+        with pytest.raises(TypeError, match=msg):
             left / right
 
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             left // right
 
     # TODO: de-duplicate with test_numeric_arr_mul_tdscalar
@@ -187,7 +188,8 @@ def test_numeric_arr_rdiv_tdscalar(self, three_days, numeric_idx, box):
         result = three_days / index
         tm.assert_equal(result, expected)
 
-        with pytest.raises(TypeError):
+        msg = "cannot use operands with types dtype"
+        with pytest.raises(TypeError, match=msg):
             index / three_days
 
     @pytest.mark.parametrize(
@@ -205,13 +207,19 @@ def test_numeric_arr_rdiv_tdscalar(self, three_days, numeric_idx, box):
     )
     def test_add_sub_timedeltalike_invalid(self, numeric_idx, other, box):
         left = tm.box_expected(numeric_idx, box)
-        with pytest.raises(TypeError):
+        msg = (
+            "unsupported operand type|"
+            "Addition/subtraction of integers and integer-arrays|"
+            "Instead of adding/subtracting|"
+            "cannot use operands with types dtype"
+        )
+        with pytest.raises(TypeError, match=msg):
             left + other
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             other + left
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             left - other
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             other - left
 
     @pytest.mark.parametrize(
@@ -229,13 +237,18 @@ def test_add_sub_datetimelike_invalid(self, numeric_idx, other, box):
         #  NullFrequencyError instead of TypeError so is excluded.
         left = tm.box_expected(numeric_idx, box)
 
-        with pytest.raises(TypeError):
+        msg = (
+            "unsupported operand type|"
+            "Cannot (add|subtract) NaT (to|from) ndarray|"
+            "Addition/subtraction of integers and integer-arrays"
+        )
+        with pytest.raises(TypeError, match=msg):
             left + other
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             other + left
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             left - other
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             other - left
 
 
@@ -607,14 +620,16 @@ def test_mul_index(self, numeric_idx):
 
     def test_mul_datelike_raises(self, numeric_idx):
         idx = numeric_idx
-        with pytest.raises(TypeError):
+        msg = "cannot perform __rmul__ with this index type"
+        with pytest.raises(TypeError, match=msg):
             idx * pd.date_range("20130101", periods=5)
 
     def test_mul_size_mismatch_raises(self, numeric_idx):
         idx = numeric_idx
-        with pytest.raises(ValueError):
+        msg = "operands could not be broadcast together"
+        with pytest.raises(ValueError, match=msg):
             idx * idx[0:3]
-        with pytest.raises(ValueError):
+        with pytest.raises(ValueError, match=msg):
             idx * np.array([1, 2])
 
     @pytest.mark.parametrize("op", [operator.pow, ops.rpow])
@@ -792,10 +807,11 @@ def test_series_frame_radd_bug(self):
 
         # really raise this time
         now = pd.Timestamp.now().to_pydatetime()
-        with pytest.raises(TypeError):
+        msg = "unsupported operand type"
+        with pytest.raises(TypeError, match=msg):
             now + ts
 
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             ts + now
 
     # TODO: This came from series.test.test_operators, needs cleanup
@@ -816,7 +832,8 @@ def test_datetime64_with_index(self):
         result = ser - ser.index
         tm.assert_series_equal(result, expected)
 
-        with pytest.raises(TypeError):
+        msg = "cannot subtract period"
+        with pytest.raises(TypeError, match=msg):
             # GH#18850
             result = ser - ser.index.to_period()
 

pandas/tests/arithmetic/test_object.py

@@ -155,9 +155,10 @@ def test_objarr_add_invalid(self, op, box_with_array):
         obj_ser.name = "objects"
 
         obj_ser = tm.box_expected(obj_ser, box)
-        with pytest.raises(Exception):
+        msg = "can only concatenate str|unsupported operand type|must be str"
+        with pytest.raises(Exception, match=msg):
             op(obj_ser, 1)
-        with pytest.raises(Exception):
+        with pytest.raises(Exception, match=msg):
             op(obj_ser, np.array(1, dtype=np.int64))
 
     # TODO: Moved from tests.series.test_operators; needs cleanup
@@ -281,13 +282,15 @@ def test_add(self):
 
     def test_sub_fail(self):
         index = tm.makeStringIndex(100)
-        with pytest.raises(TypeError):
+
+        msg = "unsupported operand type|Cannot broadcast"
+        with pytest.raises(TypeError, match=msg):
             index - "a"
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             index - index
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             index - index.tolist()
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             index.tolist() - index
 
     def test_sub_object(self):
@@ -301,10 +304,11 @@ def test_sub_object(self):
         result = index - pd.Index([Decimal(1), Decimal(1)])
         tm.assert_index_equal(result, expected)
 
-        with pytest.raises(TypeError):
+        msg = "unsupported operand type"
+        with pytest.raises(TypeError, match=msg):
             index - "foo"
 
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             index - np.array([2, "foo"])
 
     def test_rsub_object(self):
@@ -318,8 +322,9 @@ def test_rsub_object(self):
         result = np.array([Decimal(2), Decimal(2)]) - index
         tm.assert_index_equal(result, expected)
 
-        with pytest.raises(TypeError):
+        msg = "unsupported operand type"
+        with pytest.raises(TypeError, match=msg):
             "foo" - index
 
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             np.array([True, pd.Timestamp.now()]) - index

pandas/tests/arithmetic/test_timedelta64.py

@@ -48,7 +48,8 @@ def test_compare_timedelta64_zerodim(self, box_with_array):
         expected = tm.box_expected(expected, xbox)
         tm.assert_equal(res, expected)
 
-        with pytest.raises(TypeError):
+        msg = "Invalid comparison between dtype"
+        with pytest.raises(TypeError, match=msg):
             # zero-dim of wrong dtype should still raise
             tdi >= np.array(4)
 
@@ -442,7 +443,8 @@ def test_addition_ops(self):
             tdi[0:1] + dti
 
         # random indexes
-        with pytest.raises(TypeError):
+        msg = "Addition/subtraction of integers and integer-arrays"
+        with pytest.raises(TypeError, match=msg):
             tdi + pd.Int64Index([1, 2, 3])
 
         # this is a union!
@@ -604,6 +606,7 @@ def test_tdi_add_timestamp_nat_masking(self):
     def test_tdi_add_overflow(self):
         # See GH#14068
         # preliminary test scalar analogue of vectorized tests below
+        # TODO: Make raised error message more informative and test
         with pytest.raises(OutOfBoundsDatetime):
             pd.to_timedelta(106580, "D") + Timestamp("2000")
         with pytest.raises(OutOfBoundsDatetime):
@@ -700,13 +703,14 @@ def test_timedelta_ops_with_missing_values(self):
         actual = -timedelta_NaT + s1
         tm.assert_series_equal(actual, sn)
 
-        with pytest.raises(TypeError):
+        msg = "unsupported operand type"
+        with pytest.raises(TypeError, match=msg):
             s1 + np.nan
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             np.nan + s1
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             s1 - np.nan
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             -np.nan + s1
 
         actual = s1 + pd.NaT
@@ -738,9 +742,10 @@ def test_timedelta_ops_with_missing_values(self):
         actual = df1 - timedelta_NaT
         tm.assert_frame_equal(actual, dfn)
 
-        with pytest.raises(TypeError):
+        msg = "cannot subtract a datelike from|unsupported operand type"
+        with pytest.raises(TypeError, match=msg):
             df1 + np.nan
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             df1 - np.nan
 
         actual = df1 + pd.NaT  # NaT is datetime, not timedelta
@@ -957,7 +962,8 @@ def test_td64arr_add_sub_datetimelike_scalar(self, ts, box_with_array):
         tm.assert_equal(ts - tdarr, expected2)
         tm.assert_equal(ts + (-tdarr), expected2)
 
-        with pytest.raises(TypeError):
+        msg = "cannot subtract a datelike"
+        with pytest.raises(TypeError, match=msg):
             tdarr - ts
 
     def test_tdi_sub_dt64_array(self, box_with_array):
@@ -969,7 +975,8 @@ def test_tdi_sub_dt64_array(self, box_with_array):
         tdi = tm.box_expected(tdi, box_with_array)
         expected = tm.box_expected(expected, box_with_array)
 
-        with pytest.raises(TypeError):
+        msg = "cannot subtract a datelike from"
+        with pytest.raises(TypeError, match=msg):
             tdi - dtarr
 
         # TimedeltaIndex.__rsub__
@@ -1025,7 +1032,8 @@ def test_td64arr_sub_periodlike(self, box_with_array, tdi_freq, pi_freq):
 
         # TODO: parametrize over box for pi?
         tdi = tm.box_expected(tdi, box_with_array)
-        with pytest.raises(TypeError):
+        msg = "cannot subtract|unsupported operand type"
+        with pytest.raises(TypeError, match=msg):
             tdi - pi
 
         # FIXME: don't leave commented-out
@@ -1034,9 +1042,9 @@ def test_td64arr_sub_periodlike(self, box_with_array, tdi_freq, pi_freq):
         #    pi - tdi
 
         # GH#13078 subtraction of Period scalar not supported
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             tdi - pi[0]
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             pi[0] - tdi
 
     @pytest.mark.parametrize(
@@ -1499,16 +1507,17 @@ def test_td64arr_addsub_anchored_offset_arraylike(self, obox, box_with_array):
 
         # addition/subtraction ops with anchored offsets should issue
         # a PerformanceWarning and _then_ raise a TypeError.
-        with pytest.raises(TypeError):
+        msg = "has incorrect type|cannot add the type MonthEnd"
+        with pytest.raises(TypeError, match=msg):
             with tm.assert_produces_warning(PerformanceWarning):
                 tdi + anchored
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             with tm.assert_produces_warning(PerformanceWarning):
                 anchored + tdi
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             with tm.assert_produces_warning(PerformanceWarning):
                 tdi - anchored
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError, match=msg):
             with tm.assert_produces_warning(PerformanceWarning):
                 anchored - tdi
 
@@ -1533,7 +1542,8 @@ def test_td64arr_add_sub_object_array(self, box_with_array):
         expected = tm.box_expected(expected, box_with_array)
         tm.assert_equal(result, expected)
 
-        with pytest.raises(TypeError):
+        msg = "unsupported operand type|cannot subtract a datelike"
+        with pytest.raises(TypeError, match=msg):
             with tm.assert_produces_warning(warn):
                 tdarr - other
 
@@ -1588,7 +1598,8 @@ def test_td64arr_mul_int(self, box_with_array):
     def test_td64arr_mul_tdlike_scalar_raises(self, two_hours, box_with_array):
         rng = timedelta_range("1 days", "10 days", name="foo")
         rng = tm.box_expected(rng, box_with_array)
-        with pytest.raises(TypeError):
+        msg = "argument must be an integer|cannot use operands with types dtype"
+        with pytest.raises(TypeError, match=msg):
             rng * two_hours
 
     def test_tdi_mul_int_array_zerodim(self, box_with_array):
@@ -1777,12 +1788,13 @@ def test_tdarr_div_length_mismatch(self, box_with_array):
         mismatched = [1, 2, 3, 4]
 
         rng = tm.box_expected(rng, box_with_array)
+        msg = "Cannot divide vectors|Unable to coerce to Series"
         for obj in [mismatched, mismatched[:2]]:
             # one shorter, one longer
             for other in [obj, np.array(obj), pd.Index(obj)]:
-                with pytest.raises(ValueError):
+                with pytest.raises(ValueError, match=msg):
                     rng / other
-                with pytest.raises(ValueError):
+                with pytest.raises(ValueError, match=msg):
                     other / rng
 
     # ------------------------------------------------------------------
@@ -1908,7 +1920,8 @@ def test_td64arr_mod_int(self, box_with_array):
         result = tdarr % 2
         tm.assert_equal(result, expected)
 
-        with pytest.raises(TypeError):
+        msg = "Cannot divide int by"
+        with pytest.raises(TypeError, match=msg):
             2 % tdarr
 
         if box_with_array is pd.DataFrame:
@@ -1957,15 +1970,21 @@ def test_td64arr_mul_tdscalar_invalid(self, box_with_array, scalar_td):
     def test_td64arr_mul_too_short_raises(self, box_with_array):
         idx = TimedeltaIndex(np.arange(5, dtype="int64"))
         idx = tm.box_expected(idx, box_with_array)
-        with pytest.raises(TypeError):
+        msg = (
+            "cannot use operands with types dtype|"
+            "Cannot multiply with unequal lengths|"
+            "Unable to coerce to Series"
+        )
+        with pytest.raises(TypeError, match=msg):
             idx * idx[:3]
-        with pytest.raises(ValueError):
+        with pytest.raises(ValueError, match=msg):
             idx * np.array([1, 2])
 
     def test_td64arr_mul_td64arr_raises(self, box_with_array):
         idx = TimedeltaIndex(np.arange(5, dtype="int64"))
         idx = tm.box_expected(idx, box_with_array)
-        with pytest.raises(TypeError):
+        msg = "cannot use operands with types dtype"
+        with pytest.raises(TypeError, match=msg):
             idx * idx
 
     # ------------------------------------------------------------------

pandas/tests/arrays/interval/test_interval.py

@@ -152,7 +152,7 @@ def test_arrow_array():
     assert result.equals(expected)
 
     # unsupported conversions
-    with pytest.raises(TypeError):
+    with pytest.raises(TypeError, match="Not supported to convert IntervalArray"):
         pa.array(intervals, type="float64")
 
     with pytest.raises(TypeError, match="different 'subtype'"):