diff --git a/mercurial/debugcommands.py b/mercurial/debugcommands.py
--- a/mercurial/debugcommands.py
+++ b/mercurial/debugcommands.py
@@ -2961,7 +2961,7 @@
                               stringutil.escapedata(output))
             else:
                 res = peer._call(command, **pycompat.strkwargs(args))
-                ui.status(_('response: %s\n') % stringutil.escapedata(res))
+                ui.status(_('response: %s\n') % stringutil.pprint(res))
 
         elif action == 'batchbegin':
             if batchedcommands is not None:
diff --git a/mercurial/utils/stringutil.py b/mercurial/utils/stringutil.py
--- a/mercurial/utils/stringutil.py
+++ b/mercurial/utils/stringutil.py
@@ -36,6 +36,20 @@
 
     return _DATA_ESCAPE_RE.sub(lambda m: _DATA_ESCAPE_MAP[m.group(0)], s)
 
+def pprint(o):
+    """Pretty print an object."""
+    if isinstance(o, (bytes, bytearray)):
+        return "b'%s'" % escapedata(o)
+    elif isinstance(o, list):
+        return '[%s]' % (b', '.join(pprint(a) for a in o))
+    elif isinstance(o, dict):
+        return '{%s}' % (b', '.join(
+            '%s: %s' % (pprint(k), pprint(v)) for k, v in sorted(o.items())))
+    elif isinstance(o, bool):
+        return b'True' if o else b'False'
+    else:
+        raise error.ProgrammingError('do not know how to format %r' % o)
+
 def binary(s):
     """return true if a string is binary data"""
     return bool(s and '\0' in s)
diff --git a/tests/test-http-protocol.t b/tests/test-http-protocol.t
--- a/tests/test-http-protocol.t
+++ b/tests/test-http-protocol.t
@@ -209,7 +209,7 @@
   s>     bookmarks	\n
   s>     namespaces	\n
   s>     phases	
-  response: bookmarks	\nnamespaces	\nphases	
+  response: b'bookmarks	\nnamespaces	\nphases	'
 
 Same thing, but with "httprequest" command
 
diff --git a/tests/test-ssh-proto.t b/tests/test-ssh-proto.t
--- a/tests/test-ssh-proto.t
+++ b/tests/test-ssh-proto.t
@@ -1345,7 +1345,7 @@
   o>     bookmarks	\n
   o>     namespaces	\n
   o>     phases	
-  response: bookmarks	\nnamespaces	\nphases	
+  response: b'bookmarks	\nnamespaces	\nphases	'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1376,7 +1376,7 @@
   o>     bookmarks	\n
   o>     namespaces	\n
   o>     phases	
-  response: bookmarks	\nnamespaces	\nphases	
+  response: b'bookmarks	\nnamespaces	\nphases	'
 
   $ cd ..
 
@@ -1421,7 +1421,7 @@
   i> flush() -> None
   o> bufferedreadline() -> 2:
   o>     0\n
-  response: 
+  response: b''
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1448,7 +1448,7 @@
   i> flush() -> None
   o> bufferedreadline() -> 2:
   o>     0\n
-  response: 
+  response: b''
 
 With a single bookmark set
 
@@ -1483,7 +1483,7 @@
   o> bufferedreadline() -> 3:
   o>     46\n
   o> bufferedread(46) -> 46: bookA	68986213bd4485ea51533535e3fc9e78007a711f
-  response: bookA	68986213bd4485ea51533535e3fc9e78007a711f
+  response: b'bookA	68986213bd4485ea51533535e3fc9e78007a711f'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1511,7 +1511,7 @@
   o> bufferedreadline() -> 3:
   o>     46\n
   o> bufferedread(46) -> 46: bookA	68986213bd4485ea51533535e3fc9e78007a711f
-  response: bookA	68986213bd4485ea51533535e3fc9e78007a711f
+  response: b'bookA	68986213bd4485ea51533535e3fc9e78007a711f'
 
 With multiple bookmarks set
 
@@ -1548,7 +1548,7 @@
   o> bufferedread(93) -> 93:
   o>     bookA	68986213bd4485ea51533535e3fc9e78007a711f\n
   o>     bookB	1880f3755e2e52e3199e0ee5638128b08642f34d
-  response: bookA	68986213bd4485ea51533535e3fc9e78007a711f\nbookB	1880f3755e2e52e3199e0ee5638128b08642f34d
+  response: b'bookA	68986213bd4485ea51533535e3fc9e78007a711f\nbookB	1880f3755e2e52e3199e0ee5638128b08642f34d'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1578,7 +1578,7 @@
   o> bufferedread(93) -> 93:
   o>     bookA	68986213bd4485ea51533535e3fc9e78007a711f\n
   o>     bookB	1880f3755e2e52e3199e0ee5638128b08642f34d
-  response: bookA	68986213bd4485ea51533535e3fc9e78007a711f\nbookB	1880f3755e2e52e3199e0ee5638128b08642f34d
+  response: b'bookA	68986213bd4485ea51533535e3fc9e78007a711f\nbookB	1880f3755e2e52e3199e0ee5638128b08642f34d'
 
 Test pushkey for bookmarks
 
@@ -1624,7 +1624,7 @@
   o>     2\n
   o> bufferedread(2) -> 2:
   o>     1\n
-  response: 1\n
+  response: b'1\n'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1661,7 +1661,7 @@
   o>     2\n
   o> bufferedread(2) -> 2:
   o>     1\n
-  response: 1\n
+  response: b'1\n'
 
   $ hg bookmarks
      bookA                     0:68986213bd44
@@ -1707,7 +1707,7 @@
   o> bufferedreadline() -> 3:
   o>     15\n
   o> bufferedread(15) -> 15: publishing	True
-  response: publishing	True
+  response: b'publishing	True'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1735,7 +1735,7 @@
   o> bufferedreadline() -> 3:
   o>     15\n
   o> bufferedread(15) -> 15: publishing	True
-  response: publishing	True
+  response: b'publishing	True'
 
 Create some commits
 
@@ -1789,7 +1789,7 @@
   o>     20b8a89289d80036e6c4e87c2083e3bea1586637	1\n
   o>     c4750011d906c18ea2f0527419cbc1a544435150	1\n
   o>     publishing	True
-  response: 20b8a89289d80036e6c4e87c2083e3bea1586637	1\nc4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True
+  response: b'20b8a89289d80036e6c4e87c2083e3bea1586637	1\nc4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1820,7 +1820,7 @@
   o>     20b8a89289d80036e6c4e87c2083e3bea1586637	1\n
   o>     c4750011d906c18ea2f0527419cbc1a544435150	1\n
   o>     publishing	True
-  response: 20b8a89289d80036e6c4e87c2083e3bea1586637	1\nc4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True
+  response: b'20b8a89289d80036e6c4e87c2083e3bea1586637	1\nc4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True'
 
 Single draft head
 
@@ -1857,7 +1857,7 @@
   o> bufferedread(58) -> 58:
   o>     c4750011d906c18ea2f0527419cbc1a544435150	1\n
   o>     publishing	True
-  response: c4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True
+  response: b'c4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1887,7 +1887,7 @@
   o> bufferedread(58) -> 58:
   o>     c4750011d906c18ea2f0527419cbc1a544435150	1\n
   o>     publishing	True
-  response: c4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True
+  response: b'c4750011d906c18ea2f0527419cbc1a544435150	1\npublishing	True'
 
 All public heads
 
@@ -1922,7 +1922,7 @@
   o> bufferedreadline() -> 3:
   o>     15\n
   o> bufferedread(15) -> 15: publishing	True
-  response: publishing	True
+  response: b'publishing	True'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -1950,7 +1950,7 @@
   o> bufferedreadline() -> 3:
   o>     15\n
   o> bufferedread(15) -> 15: publishing	True
-  response: publishing	True
+  response: b'publishing	True'
 
 Setting public phase via pushkey
 
@@ -1999,7 +1999,7 @@
   o>     2\n
   o> bufferedread(2) -> 2:
   o>     1\n
-  response: 1\n
+  response: b'1\n'
   
   testing ssh2
   creating ssh peer from handshake results
@@ -2037,7 +2037,7 @@
   o>     2\n
   o> bufferedread(2) -> 2:
   o>     1\n
-  response: 1\n
+  response: b'1\n'
 
   $ hg phase .
   4: public