Change Exception message

See pytest-dev#7489

AUTHORS

@@ -164,6 +164,7 @@ Kyle Altendorf
 Lawrence Mitchell
 Lee Kamentsky
 Lev Maximov
+Lewis Cowles
 Llandy Riveron Del Risco
 Loic Esteve
 Lukas Bednar

changelog/7489.improvement.rst

@@ -0,0 +1 @@
+The ``raises()`` method of ``_pytest.python_api`` has a clearer error message.

src/_pytest/_code/code.py

@@ -609,9 +609,10 @@ def match(self, regexp: "Union[str, Pattern]") -> "Literal[True]":
         If it matches `True` is returned, otherwise an `AssertionError` is raised.
         """
         __tracebackhide__ = True
-        assert re.search(
+        regextest = re.search(regexp, str(self.value))
+        assert regextest, "Regex pattern r{!r} does not match {!r}".format(
             regexp, str(self.value)
-        ), "Pattern {!r} does not match {!r}".format(regexp, str(self.value))
+        )
         # Return True to allow for "assert excinfo.match()".
         return True
 

testing/code/test_excinfo.py

@@ -423,7 +423,7 @@ def test_division_zero():
     result = testdir.runpytest()
     assert result.ret != 0
 
-    exc_msg = "Pattern '[[]123[]]+' does not match 'division by zero'"
+    exc_msg = "Regex pattern r'[[]123[]]+' does not match 'division by zero'"
     result.stdout.fnmatch_lines(["E * AssertionError: {}".format(exc_msg)])
     result.stdout.no_fnmatch_line("*__tracebackhide__ = True*")
 

testing/python/raises.py

@@ -197,7 +197,7 @@ def test_raises_match(self) -> None:
             int("asdf")
 
         msg = "with base 16"
-        expr = "Pattern {!r} does not match \"invalid literal for int() with base 10: 'asdf'\"".format(
+        expr = "Regex pattern r{!r} does not match \"invalid literal for int() with base 10: 'asdf'\"".format(
             msg
         )
         with pytest.raises(AssertionError, match=re.escape(expr)):
@@ -223,7 +223,7 @@ def test_match_failure_string_quoting(self):
             with pytest.raises(AssertionError, match="'foo"):
                 raise AssertionError("'bar")
         (msg,) = excinfo.value.args
-        assert msg == 'Pattern "\'foo" does not match "\'bar"'
+        assert msg == 'Regex pattern r"\'foo" does not match "\'bar"'
 
     def test_raises_match_wrong_type(self):
         """Raising an exception with the wrong type and match= given.