Merge pull request #5223 from 5uper5hoot/patch-1

 Clarify docs for pytest.raises `match`.

Author: nicoddemus

src/_pytest/python_api.py

@@ -558,7 +558,13 @@ def raises(expected_exception, *args, **kwargs):
     Assert that a code block/function call raises ``expected_exception``
     or raise a failure exception otherwise.
 
-    :kwparam match: if specified, asserts that the exception matches a text or regex
+    :kwparam match: if specified, a string containing a regular expression,
+        or a regular expression object, that is tested against the string
+        representation of the exception using ``re.match``. To match a literal
+        string that may contain `special characters`__, the pattern can
+        first be escaped with ``re.escape``.
+
+    __ https://docs.python.org/3/library/re.html#regular-expression-syntax
 
     :kwparam message: **(deprecated since 4.1)** if specified, provides a custom failure message
         if the exception is not raised. See :ref:`the deprecation docs <raises message deprecated>` for a workaround.