diff --git a/doc/en/example/assertion/global_testmodule_config/conftest.py b/doc/en/example/assertion/global_testmodule_config/conftest.py
index 4859bea78..3597ec06d 100644
--- a/doc/en/example/assertion/global_testmodule_config/conftest.py
+++ b/doc/en/example/assertion/global_testmodule_config/conftest.py
@@ -10,4 +10,4 @@ def pytest_runtest_setup(item):
             return
         mod = item.getparent(pytest.Module).obj
         if hasattr(mod, "hello"):
-            print("mod.hello %r" % (mod.hello,))
+            print("mod.hello {!r}".format(mod.hello))
diff --git a/doc/en/example/multipython.py b/doc/en/example/multipython.py
index 299833f71..5e12c9b03 100644
--- a/doc/en/example/multipython.py
+++ b/doc/en/example/multipython.py
@@ -2,9 +2,10 @@
 module containing a parametrized tests testing cross-python
 serialization via the pickle module.
 """
+import textwrap
+
 import py
 import pytest
-import _pytest._code
 
 pythonlist = ["python2.7", "python3.4", "python3.5"]
 
@@ -24,42 +25,44 @@ class Python(object):
     def __init__(self, version, picklefile):
         self.pythonpath = py.path.local.sysfind(version)
         if not self.pythonpath:
-            pytest.skip("%r not found" % (version,))
+            pytest.skip("{!r} not found".format(version))
         self.picklefile = picklefile
 
     def dumps(self, obj):
         dumpfile = self.picklefile.dirpath("dump.py")
         dumpfile.write(
-            _pytest._code.Source(
-                """
-            import pickle
-            f = open(%r, 'wb')
-            s = pickle.dump(%r, f, protocol=2)
-            f.close()
-        """
-                % (str(self.picklefile), obj)
+            textwrap.dedent(
+                """\
+                import pickle
+                f = open({!r}, 'wb')
+                s = pickle.dump({!r}, f, protocol=2)
+                f.close()
+                """.format(
+                    str(self.picklefile), obj
+                )
             )
         )
-        py.process.cmdexec("%s %s" % (self.pythonpath, dumpfile))
+        py.process.cmdexec("{} {}".format(self.pythonpath, dumpfile))
 
     def load_and_is_true(self, expression):
         loadfile = self.picklefile.dirpath("load.py")
         loadfile.write(
-            _pytest._code.Source(
-                """
-            import pickle
-            f = open(%r, 'rb')
-            obj = pickle.load(f)
-            f.close()
-            res = eval(%r)
-            if not res:
-                raise SystemExit(1)
-        """
-                % (str(self.picklefile), expression)
+            textwrap.dedent(
+                """\
+                import pickle
+                f = open({!r}, 'rb')
+                obj = pickle.load(f)
+                f.close()
+                res = eval({!r})
+                if not res:
+                    raise SystemExit(1)
+                """.format(
+                    str(self.picklefile), expression
+                )
             )
         )
         print(loadfile)
-        py.process.cmdexec("%s %s" % (self.pythonpath, loadfile))
+        py.process.cmdexec("{} {}".format(self.pythonpath, loadfile))
 
 
 @pytest.mark.parametrize("obj", [42, {}, {1: 3}])
diff --git a/src/_pytest/_code/_py2traceback.py b/src/_pytest/_code/_py2traceback.py
index 2dd100c33..cceed40ed 100644
--- a/src/_pytest/_code/_py2traceback.py
+++ b/src/_pytest/_code/_py2traceback.py
@@ -2,7 +2,7 @@
 # CHANGES:
 # - some_str is replaced, trying to create unicode strings
 #
-from __future__ import absolute_import, division, print_function
+from __future__ import absolute_import, division, print_function, unicode_literals
 import types
 from six import text_type
 
@@ -51,17 +51,17 @@ def format_exception_only(etype, value):
         pass
     else:
         filename = filename or "<string>"
-        lines.append('  File "%s", line %d\n' % (filename, lineno))
+        lines.append('  File "{}", line {}\n'.format(filename, lineno))
         if badline is not None:
             if isinstance(badline, bytes):  # python 2 only
                 badline = badline.decode("utf-8", "replace")
-            lines.append(u"    %s\n" % badline.strip())
+            lines.append("    {}\n".format(badline.strip()))
             if offset is not None:
                 caretspace = badline.rstrip("\n")[:offset].lstrip()
                 # non-space whitespace (likes tabs) must be kept for alignment
                 caretspace = ((c.isspace() and c or " ") for c in caretspace)
                 # only three spaces to account for offset1 == pos 0
-                lines.append("   %s^\n" % "".join(caretspace))
+                lines.append("   {}^\n".format("".join(caretspace)))
         value = msg
 
     lines.append(_format_final_exc_line(stype, value))
@@ -72,9 +72,9 @@ def _format_final_exc_line(etype, value):
     """Return a list of a single line -- normal case for format_exception_only"""
     valuestr = _some_str(value)
     if value is None or not valuestr:
-        line = "%s\n" % etype
+        line = "{}\n".format(etype)
     else:
-        line = "%s: %s\n" % (etype, valuestr)
+        line = "{}: {}\n".format(etype, valuestr)
     return line
 
 
@@ -83,7 +83,7 @@ def _some_str(value):
         return text_type(value)
     except Exception:
         try:
-            return str(value)
+            return bytes(value).decode("UTF-8", "replace")
         except Exception:
             pass
-    return "<unprintable %s object>" % type(value).__name__
+    return "<unprintable {} object>".format(type(value).__name__)
diff --git a/testing/acceptance_test.py b/testing/acceptance_test.py
index 52879f15c..428ac464c 100644
--- a/testing/acceptance_test.py
+++ b/testing/acceptance_test.py
@@ -131,7 +131,7 @@ class TestGeneralUsage(object):
         p2 = testdir.makefile(".pyc", "123")
         result = testdir.runpytest(p1, p2)
         assert result.ret
-        result.stderr.fnmatch_lines(["*ERROR: not found:*%s" % (p2.basename,)])
+        result.stderr.fnmatch_lines(["*ERROR: not found:*{}".format(p2.basename)])
 
     def test_issue486_better_reporting_on_conftest_load_failure(self, testdir):
         testdir.makepyfile("")
@@ -453,7 +453,7 @@ class TestInvocationVariants(object):
     @pytest.mark.xfail("sys.platform.startswith('java')")
     def test_pydoc(self, testdir):
         for name in ("py.test", "pytest"):
-            result = testdir.runpython_c("import %s;help(%s)" % (name, name))
+            result = testdir.runpython_c("import {};help({})".format(name, name))
             assert result.ret == 0
             s = result.stdout.str()
             assert "MarkGenerator" in s
@@ -836,7 +836,7 @@ class TestDurations(object):
                     if ("test_%s" % x) in line and y in line:
                         break
                 else:
-                    raise AssertionError("not found %s %s" % (x, y))
+                    raise AssertionError("not found {} {}".format(x, y))
 
     def test_with_deselected(self, testdir):
         testdir.makepyfile(self.source)
diff --git a/testing/code/test_excinfo.py b/testing/code/test_excinfo.py
index 52cad6a3e..6723a8806 100644
--- a/testing/code/test_excinfo.py
+++ b/testing/code/test_excinfo.py
@@ -270,7 +270,7 @@ class TestTraceback_f_g_h(object):
         decorator = pytest.importorskip("decorator").decorator
 
         def log(f, *k, **kw):
-            print("%s %s" % (k, kw))
+            print("{} {}".format(k, kw))
             f(*k, **kw)
 
         log = decorator(log)
diff --git a/testing/test_argcomplete.py b/testing/test_argcomplete.py
index 9e6b711a2..fc2306b00 100644
--- a/testing/test_argcomplete.py
+++ b/testing/test_argcomplete.py
@@ -11,7 +11,7 @@ def equal_with_bash(prefix, ffc, fc, out=None):
     res_bash = set(fc(prefix))
     retval = set(res) == res_bash
     if out:
-        out.write("equal_with_bash %s %s\n" % (retval, res))
+        out.write("equal_with_bash {} {}\n".format(retval, res))
         if not retval:
             out.write(" python - bash: %s\n" % (set(res) - res_bash))
             out.write(" bash - python: %s\n" % (res_bash - set(res)))
diff --git a/testing/test_assertrewrite.py b/testing/test_assertrewrite.py
index 4074b80dc..79e7cf0e3 100644
--- a/testing/test_assertrewrite.py
+++ b/testing/test_assertrewrite.py
@@ -561,7 +561,7 @@ class TestAssertionRewrite(object):
         assert getmsg(f) == "assert 42"
 
         def my_reprcompare(op, left, right):
-            return "%s %s %s" % (left, op, right)
+            return "{} {} {}".format(left, op, right)
 
         monkeypatch.setattr(util, "_reprcompare", my_reprcompare)
 
diff --git a/testing/test_helpconfig.py b/testing/test_helpconfig.py
index b5424235b..ceea56ccc 100644
--- a/testing/test_helpconfig.py
+++ b/testing/test_helpconfig.py
@@ -7,7 +7,9 @@ def test_version(testdir, pytestconfig):
     result = testdir.runpytest("--version")
     assert result.ret == 0
     # p = py.path.local(py.__file__).dirpath()
-    result.stderr.fnmatch_lines(["*pytest*%s*imported from*" % (pytest.__version__,)])
+    result.stderr.fnmatch_lines(
+        ["*pytest*{}*imported from*".format(pytest.__version__)]
+    )
     if pytestconfig.pluginmanager.list_plugin_distinfo():
         result.stderr.fnmatch_lines(["*setuptools registered plugins:", "*at*"])
 
diff --git a/testing/test_parseopt.py b/testing/test_parseopt.py
index 3870ad419..fab288e7f 100644
--- a/testing/test_parseopt.py
+++ b/testing/test_parseopt.py
@@ -294,7 +294,7 @@ def test_argcomplete(testdir, monkeypatch):
     script = str(testdir.tmpdir.join("test_argcomplete"))
     pytest_bin = sys.argv[0]
     if "pytest" not in os.path.basename(pytest_bin):
-        pytest.skip("need to be run with pytest executable, not %s" % (pytest_bin,))
+        pytest.skip("need to be run with pytest executable, not {}".format(pytest_bin))
 
     with open(str(script), "w") as fp:
         # redirect output from argcomplete to stdin and stderr is not trivial
diff --git a/testing/test_pdb.py b/testing/test_pdb.py
index 43a78908c..ed1c49a1a 100644
--- a/testing/test_pdb.py
+++ b/testing/test_pdb.py
@@ -260,7 +260,9 @@ class TestPDB(object):
                 assert False
         """
         )
-        child = testdir.spawn_pytest("--show-capture=%s --pdb %s" % (showcapture, p1))
+        child = testdir.spawn_pytest(
+            "--show-capture={} --pdb {}".format(showcapture, p1)
+        )
         if showcapture in ("all", "log"):
             child.expect("captured log")
             child.expect("get rekt")
@@ -473,7 +475,7 @@ class TestPDB(object):
             x = 5
         """
         )
-        child = testdir.spawn("%s %s" % (sys.executable, p1))
+        child = testdir.spawn("{} {}".format(sys.executable, p1))
         child.expect("x = 5")
         child.sendeof()
         self.flush(child)
diff --git a/testing/test_terminal.py b/testing/test_terminal.py
index 0f674a34f..f377c3ca9 100644
--- a/testing/test_terminal.py
+++ b/testing/test_terminal.py
@@ -1118,9 +1118,9 @@ def test_terminal_summary_warnings_are_displayed(testdir):
 )
 def test_summary_stats(exp_line, exp_color, stats_arg):
     print("Based on stats: %s" % stats_arg)
-    print('Expect summary: "%s"; with color "%s"' % (exp_line, exp_color))
+    print('Expect summary: "{}"; with color "{}"'.format(exp_line, exp_color))
     (line, color) = build_summary_stats_line(stats_arg)
-    print('Actually got:   "%s"; with color "%s"' % (line, color))
+    print('Actually got:   "{}"; with color "{}"'.format(line, color))
     assert line == exp_line
     assert color == exp_color