diff --git a/tests/test-annotate.py b/tests/test-annotate.py
--- a/tests/test-annotate.py
+++ b/tests/test-annotate.py
@@ -36,17 +36,17 @@
         p1ann = decorate(p1data, p1fctx)
         p1ann = _annotatepair([oldann], p1fctx, p1ann, False, diffopts)
         self.assertEqual(p1ann[0], [
-            annotateline('old', 1),
-            annotateline('old', 2),
-            annotateline('p1', 3),
+            annotateline(b'old', 1),
+            annotateline(b'old', 2),
+            annotateline(b'p1', 3),
         ])
 
         p2ann = decorate(p2data, p2fctx)
         p2ann = _annotatepair([oldann], p2fctx, p2ann, False, diffopts)
         self.assertEqual(p2ann[0], [
-            annotateline('old', 1),
-            annotateline('p2', 2),
-            annotateline('p2', 3),
+            annotateline(b'old', 1),
+            annotateline(b'p2', 2),
+            annotateline(b'p2', 3),
         ])
 
         # Test with multiple parents (note the difference caused by ordering)
@@ -55,22 +55,22 @@
         childann = _annotatepair([p1ann, p2ann], childfctx, childann, False,
                                  diffopts)
         self.assertEqual(childann[0], [
-            annotateline('old', 1),
-            annotateline('c', 2),
-            annotateline('p2', 2),
-            annotateline('c', 4),
-            annotateline('p2', 3),
+            annotateline(b'old', 1),
+            annotateline(b'c', 2),
+            annotateline(b'p2', 2),
+            annotateline(b'c', 4),
+            annotateline(b'p2', 3),
         ])
 
         childann = decorate(childdata, childfctx)
         childann = _annotatepair([p2ann, p1ann], childfctx, childann, False,
                                  diffopts)
         self.assertEqual(childann[0], [
-            annotateline('old', 1),
-            annotateline('c', 2),
-            annotateline('p1', 3),
-            annotateline('c', 4),
-            annotateline('p2', 3),
+            annotateline(b'old', 1),
+            annotateline(b'c', 2),
+            annotateline(b'p1', 3),
+            annotateline(b'c', 4),
+            annotateline(b'p2', 3),
         ])
 
         # Test with skipchild (note the difference caused by ordering)
@@ -79,24 +79,24 @@
         childann = _annotatepair([p1ann, p2ann], childfctx, childann, True,
                                  diffopts)
         self.assertEqual(childann[0], [
-            annotateline('old', 1),
-            annotateline('old', 2, True),
+            annotateline(b'old', 1),
+            annotateline(b'old', 2, True),
             # note that this line was carried over from earlier so it is *not*
             # marked skipped
-            annotateline('p2', 2),
-            annotateline('p2', 2, True),
-            annotateline('p2', 3),
+            annotateline(b'p2', 2),
+            annotateline(b'p2', 2, True),
+            annotateline(b'p2', 3),
         ])
 
         childann = decorate(childdata, childfctx)
         childann = _annotatepair([p2ann, p1ann], childfctx, childann, True,
                                  diffopts)
         self.assertEqual(childann[0], [
-            annotateline('old', 1),
-            annotateline('old', 2, True),
-            annotateline('p1', 3),
-            annotateline('p1', 3, True),
-            annotateline('p2', 3),
+            annotateline(b'old', 1),
+            annotateline(b'old', 2, True),
+            annotateline(b'p1', 3),
+            annotateline(b'p1', 3, True),
+            annotateline(b'p2', 3),
         ])
 
 if __name__ == '__main__':
diff --git a/tests/test-arbitraryfilectx.t b/tests/test-arbitraryfilectx.t
--- a/tests/test-arbitraryfilectx.t
+++ b/tests/test-arbitraryfilectx.t
@@ -7,9 +7,9 @@
   > command = registrar.command(cmdtable)
   > @command(b'eval', [], 'hg eval CMD')
   > def eval_(ui, repo, *cmds, **opts):
-  >     cmd = " ".join(cmds)
+  >     cmd = b" ".join(cmds)
   >     res = str(eval(cmd, globals(), locals()))
-  >     ui.warn("%s" % res)
+  >     ui.warn(b"%s" % res)
   > EOF
 
   $ echo "[extensions]" >> $HGRCPATH
diff --git a/tests/test-check-help.t b/tests/test-check-help.t
--- a/tests/test-check-help.t
+++ b/tests/test-check-help.t
@@ -10,7 +10,7 @@
   >     import os, msvcrt
   >     msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
   > topics = set()
-  > topicre = re.compile(r':hg:`help ([a-z0-9\-.]+)`')
+  > topicre = re.compile(br':hg:`help ([a-z0-9\-.]+)`')
   > for fname in sys.argv:
   >     with open(fname) as f:
   >         topics.update(m.group(1) for m in topicre.finditer(f.read()))
diff --git a/tests/test-conflict.t b/tests/test-conflict.t
--- a/tests/test-conflict.t
+++ b/tests/test-conflict.t
@@ -139,8 +139,8 @@
   $ hg up -q --clean .
   $ $PYTHON <<EOF
   > fp = open('logfile', 'w')
-  > fp.write('12345678901234567890123456789012345678901234567890' +
-  >          '1234567890') # there are 5 more columns for 80 columns
+  > fp.write(b'12345678901234567890123456789012345678901234567890' +
+  >          b'1234567890') # there are 5 more columns for 80 columns
   > 
   > # 2 x 4 = 8 columns, but 3 x 4 = 12 bytes
   > fp.write(u'\u3042\u3044\u3046\u3048'.encode('utf-8'))
diff --git a/tests/test-diff-binary-file.t b/tests/test-diff-binary-file.t
--- a/tests/test-diff-binary-file.t
+++ b/tests/test-diff-binary-file.t
@@ -81,7 +81,7 @@
   $ cat > writebin.py <<EOF
   > import sys
   > path = sys.argv[1]
-  > open(path, 'wb').write('\x00\x01\x02\x03')
+  > open(path, 'wb').write(b'\x00\x01\x02\x03')
   > EOF
   $ $PYTHON writebin.py binfile.bin
   $ hg add binfile.bin