diff --git a/src/_pytest/compat.py b/src/_pytest/compat.py
index 6a62e88cfca..f0b0d548f07 100644
--- a/src/_pytest/compat.py
+++ b/src/_pytest/compat.py
@@ -307,7 +307,7 @@ def get_real_method(obj, holder):
     return obj
 
 
-def getfslineno(obj):
+def getfslineno(obj) -> Tuple[Union[str, py.path.local], int]:
     # xxx let decorators etc specify a sane ordering
     obj = get_real_func(obj)
     if hasattr(obj, "place_as"):
diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index 7cbb676bd70..8817c57495a 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -82,8 +82,8 @@ def parse(self, args, namespace=None):
 
         self.optparser = self._getparser()
         try_argcomplete(self.optparser)
-        args = [str(x) if isinstance(x, py.path.local) else x for x in args]
-        return self.optparser.parse_args(args, namespace=namespace)
+        strargs = [str(x) if isinstance(x, py.path.local) else x for x in args]
+        return self.optparser.parse_args(strargs, namespace=namespace)
 
     def _getparser(self) -> "MyOptionParser":
         from _pytest._argcomplete import filescompleter
@@ -124,8 +124,8 @@ def parse_known_and_unknown_args(
         the remaining arguments unknown at this point.
         """
         optparser = self._getparser()
-        args = [str(x) if isinstance(x, py.path.local) else x for x in args]
-        return optparser.parse_known_args(args, namespace=namespace)
+        strargs = [str(x) if isinstance(x, py.path.local) else x for x in args]
+        return optparser.parse_known_args(strargs, namespace=namespace)
 
     def addini(self, name, help, type=None, default=None):
         """ register an ini-file option.
diff --git a/src/_pytest/config/findpaths.py b/src/_pytest/config/findpaths.py
index 707ce969d93..fb84160c1ff 100644
--- a/src/_pytest/config/findpaths.py
+++ b/src/_pytest/config/findpaths.py
@@ -1,6 +1,9 @@
 import os
+from typing import Any
+from typing import Iterable
 from typing import List
 from typing import Optional
+from typing import Tuple
 
 import py
 
@@ -60,7 +63,7 @@ def getcfg(args, config=None):
     return None, None, None
 
 
-def get_common_ancestor(paths):
+def get_common_ancestor(paths: Iterable[py.path.local]) -> py.path.local:
     common_ancestor = None
     for path in paths:
         if not path.exists():
@@ -113,7 +116,7 @@ def determine_setup(
     args: List[str],
     rootdir_cmd_arg: Optional[str] = None,
     config: Optional["Config"] = None,
-):
+) -> Tuple[py.path.local, Optional[str], Any]:
     dirs = get_dirs_from_args(args)
     if inifile:
         iniconfig = py.iniconfig.IniConfig(inifile)
diff --git a/src/_pytest/doctest.py b/src/_pytest/doctest.py
index e62c5e17ea4..d7ca888cc5f 100644
--- a/src/_pytest/doctest.py
+++ b/src/_pytest/doctest.py
@@ -308,7 +308,7 @@ def repr_failure(self, excinfo):
         else:
             return super().repr_failure(excinfo)
 
-    def reportinfo(self) -> Tuple[str, int, str]:
+    def reportinfo(self) -> Tuple[py.path.local, int, str]:
         return self.fspath, self.dtest.lineno, "[doctest] %s" % self.name
 
 
diff --git a/src/_pytest/fixtures.py b/src/_pytest/fixtures.py
index bae3d071674..f0a1a2ed078 100644
--- a/src/_pytest/fixtures.py
+++ b/src/_pytest/fixtures.py
@@ -351,7 +351,7 @@ def __init__(self, pyfuncitem):
         self.fixturename = None
         #: Scope string, one of "function", "class", "module", "session"
         self.scope = "function"
-        self._fixture_defs = {}  # argname -> FixtureDef
+        self._fixture_defs = {}  # type: Dict[str, FixtureDef]
         fixtureinfo = pyfuncitem._fixtureinfo
         self._arg2fixturedefs = fixtureinfo.name2fixturedefs.copy()
         self._arg2index = {}
@@ -426,7 +426,8 @@ def module(self):
     @scopeproperty()
     def fspath(self) -> py.path.local:
         """ the file system path of the test module which collected this test. """
-        return self._pyfuncitem.fspath
+        # TODO: Remove ignore once _pyfuncitem is properly typed.
+        return self._pyfuncitem.fspath  # type: ignore
 
     @property
     def keywords(self):
@@ -549,7 +550,9 @@ def _compute_fixture_value(self, fixturedef):
                 source_lineno = frameinfo.lineno
                 source_path = py.path.local(source_path)
                 if source_path.relto(funcitem.config.rootdir):
-                    source_path = source_path.relto(funcitem.config.rootdir)
+                    source_path_str = source_path.relto(funcitem.config.rootdir)
+                else:
+                    source_path_str = str(source_path)
                 msg = (
                     "The requested fixture has no parameter defined for test:\n"
                     "    {}\n\n"
@@ -558,7 +561,7 @@ def _compute_fixture_value(self, fixturedef):
                         funcitem.nodeid,
                         fixturedef.argname,
                         getlocation(fixturedef.func, funcitem.config.rootdir),
-                        source_path,
+                        source_path_str,
                         source_lineno,
                     )
                 )
diff --git a/src/_pytest/main.py b/src/_pytest/main.py
index 5137713d95c..ae115b1f8a9 100644
--- a/src/_pytest/main.py
+++ b/src/_pytest/main.py
@@ -376,9 +376,9 @@ class Failed(Exception):
 
 @attr.s
 class _bestrelpath_cache(dict):
-    path = attr.ib()
+    path = attr.ib(type=py.path.local)
 
-    def __missing__(self, path: str) -> str:
+    def __missing__(self, path: py.path.local) -> str:
         r = self.path.bestrelpath(path)  # type: str
         self[path] = r
         return r
@@ -412,7 +412,7 @@ def __init__(self, config: Config) -> None:
 
         self._bestrelpathcache = _bestrelpath_cache(
             config.rootdir
-        )  # type: Dict[str, str]
+        )  # type: Dict[py.path.local, str]
 
         self.config.pluginmanager.register(self, name="session")
 
@@ -425,7 +425,7 @@ def __repr__(self):
             self.testscollected,
         )
 
-    def _node_location_to_relpath(self, node_path: str) -> str:
+    def _node_location_to_relpath(self, node_path: py.path.local) -> str:
         # bestrelpath is a quite slow function
         return self._bestrelpathcache[node_path]
 
diff --git a/src/_pytest/nodes.py b/src/_pytest/nodes.py
index 3cfbf46264c..ab976efae72 100644
--- a/src/_pytest/nodes.py
+++ b/src/_pytest/nodes.py
@@ -462,6 +462,10 @@ def reportinfo(self) -> Tuple[Union[py.path.local, str], Optional[int], str]:
     @cached_property
     def location(self) -> Tuple[str, Optional[int], str]:
         location = self.reportinfo()
-        fspath = self.session._node_location_to_relpath(location[0])
+        if isinstance(location[0], py.path.local):
+            fspath = location[0]
+        else:
+            fspath = py.path.local(location[0])
+        relfspath = self.session._node_location_to_relpath(fspath)
         assert type(location[2]) is str
-        return (fspath, location[1], location[2])
+        return (relfspath, location[1], location[2])
diff --git a/src/_pytest/python.py b/src/_pytest/python.py
index bc35ccf5f10..82dca3bcc9b 100644
--- a/src/_pytest/python.py
+++ b/src/_pytest/python.py
@@ -12,6 +12,7 @@
 from textwrap import dedent
 from typing import List
 from typing import Tuple
+from typing import Union
 
 import py
 
@@ -280,15 +281,16 @@ def getmodpath(self, stopatmodule=True, includemodule=False):
         parts.reverse()
         return ".".join(parts)
 
-    def reportinfo(self) -> Tuple[str, int, str]:
+    def reportinfo(self) -> Tuple[Union[py.path.local, str], int, str]:
         # XXX caching?
         obj = self.obj
         compat_co_firstlineno = getattr(obj, "compat_co_firstlineno", None)
         if isinstance(compat_co_firstlineno, int):
             # nose compatibility
-            fspath = sys.modules[obj.__module__].__file__
-            if fspath.endswith(".pyc"):
-                fspath = fspath[:-1]
+            file_path = sys.modules[obj.__module__].__file__
+            if file_path.endswith(".pyc"):
+                file_path = file_path[:-1]
+            fspath = file_path  # type: Union[py.path.local, str]
             lineno = compat_co_firstlineno
         else:
             fspath, lineno = getfslineno(obj)
@@ -367,7 +369,12 @@ def collect(self):
                 if not isinstance(res, list):
                     res = [res]
                 values.extend(res)
-        values.sort(key=lambda item: item.reportinfo()[:2])
+
+        def sort_key(item):
+            fspath, lineno, _ = item.reportinfo()
+            return (str(fspath), lineno)
+
+        values.sort(key=sort_key)
         return values
 
     def _makeitem(self, name, obj):
diff --git a/testing/test_nose.py b/testing/test_nose.py
index 469c127afc4..b6200c6c9ad 100644
--- a/testing/test_nose.py
+++ b/testing/test_nose.py
@@ -377,15 +377,48 @@ def test_io(self):
     result.stdout.fnmatch_lines(["* 1 skipped *"])
 
 
-def test_issue_6517(testdir):
+def test_raises(testdir):
     testdir.makepyfile(
         """
         from nose.tools import raises
 
         @raises(RuntimeError)
-        def test_fail_without_tcp():
+        def test_raises_runtimeerror():
             raise RuntimeError
+
+        @raises(Exception)
+        def test_raises_baseexception_not_caught():
+            raise BaseException
+
+        @raises(BaseException)
+        def test_raises_baseexception_caught():
+            raise BaseException
         """
     )
-    result = testdir.runpytest()
-    result.stdout.fnmatch_lines(["* 1 passed *"])
+    result = testdir.runpytest("-vv")
+    result.stdout.fnmatch_lines(
+        [
+            "test_raises.py::test_raises_runtimeerror PASSED*",
+            "test_raises.py::test_raises_baseexception_not_caught FAILED*",
+            "test_raises.py::test_raises_baseexception_caught PASSED*",
+            "*= FAILURES =*",
+            "*_ test_raises_baseexception_not_caught _*",
+            "",
+            "arg = (), kw = {}",
+            "",
+            "    def newfunc(*arg, **kw):",
+            "        try:",
+            ">           func(*arg, **kw)",
+            "",
+            "*/nose/*: ",
+            "_ _ *",
+            "",
+            "    @raises(Exception)",
+            "    def test_raises_baseexception_not_caught():",
+            ">       raise BaseException",
+            "E       BaseException",
+            "",
+            "test_raises.py:9: BaseException",
+            "* 1 failed, 2 passed *",
+        ]
+    )