Make 'request' a reserved name for fixtures

src/_pytest/compat.py

@@ -50,11 +50,11 @@ def iscoroutinefunction(func):
     )
 
 
-def getlocation(function, curdir):
+def getlocation(function, curdir=None):
     function = get_real_func(function)
     fn = py.path.local(inspect.getfile(function))
     lineno = function.__code__.co_firstlineno
-    if fn.relto(curdir):
+    if curdir is not None and fn.relto(curdir):
         fn = fn.relto(curdir)
     return "%s:%d" % (fn, lineno + 1)
 

src/_pytest/config/__init__.py

@@ -18,6 +18,7 @@ from pluggy import PluginManager
 
 import _pytest._code
 import _pytest.assertion
+import _pytest.deprecated
 import _pytest.hookspec  # the extension point definitions
 from .exceptions import PrintHelp
 from .exceptions import UsageError

src/_pytest/deprecated.py

@@ -19,11 +19,6 @@ DEPRECATED_EXTERNAL_PLUGINS = {
 }
 
 
-FIXTURE_NAMED_REQUEST = PytestDeprecationWarning(
-    "'request' is a reserved name for fixtures and will raise an error in future versions"
-)
-
-
 FUNCARGNAMES = PytestDeprecationWarning(
     "The `funcargnames` attribute was an alias for `fixturenames`, "
     "since pytest 2.3 - use the newer attribute instead."

src/_pytest/fixtures.py

@@ -2,7 +2,6 @@ import functools
 import inspect
 import itertools
 import sys
-import warnings
 from collections import defaultdict
 from collections import deque
 from collections import OrderedDict
@@ -26,7 +25,6 @@ from _pytest.compat import getlocation
 from _pytest.compat import is_generator
 from _pytest.compat import NOTSET
 from _pytest.compat import safe_getattr
-from _pytest.deprecated import FIXTURE_NAMED_REQUEST
 from _pytest.outcomes import fail
 from _pytest.outcomes import TEST_OUTCOME
 
@@ -971,7 +969,13 @@ class FixtureFunctionMarker:
 
         name = self.name or function.__name__
         if name == "request":
-            warnings.warn(FIXTURE_NAMED_REQUEST)
+            location = getlocation(function)
+            fail(
+                "'request' is a reserved word for fixtures, use another name:\n  {}".format(
+                    location
+                ),
+                pytrace=False,
+            )
         function._pytestfixturefunction = self
         return function