Force ASCII-only prompt when using PyPy

docs/source/usage/other.rst

@@ -152,4 +152,7 @@ class from :py:class:`pdb.Pdb` and decorate it with
 
 just like you used ``python -m pdb``.
 
-.. warning: PyPy is not supported, PyPy3 is.
+.. warning:
+   Using PyPy (not PyPy3) forces ASCII-only prompts. In other cases unicode 
+   characters are allowed, even if you use `pdbpp 
+   <https://pypi.python.org/pypi/pdbpp>`_.

powerline/pdb.py

@@ -1,6 +1,9 @@
 # vim:fileencoding=utf-8:noet
 from __future__ import (unicode_literals, division, absolute_import, print_function)
 
+import sys
+import platform
+
 from powerline import Powerline
 
 
@@ -17,3 +20,6 @@ class PDBPowerline(Powerline):
 	def do_setup(self, pdb):
 		self.update_renderer()
 		self.renderer.set_pdb(pdb)
+
+	if sys.version_info < (3,) and platform.python_implementation() == 'PyPy':
+		get_encoding = staticmethod(lambda: 'ascii')

powerline/renderers/pdb.py

@@ -1,6 +1,9 @@
 # vim:fileencoding=utf-8:noet
 from __future__ import (unicode_literals, division, absolute_import, print_function)
 
+import sys
+import platform
+
 from powerline.renderers.shell.readline import ReadlineRenderer
 from powerline.renderer import Renderer
 
@@ -35,5 +38,13 @@ class PDBRenderer(ReadlineRenderer):
 			self.initial_stack_length = len(self.pdb.stack) - 1
 		return Renderer.render(self, **kwargs)
 
+	if sys.version_info < (3,) and platform.python_implementation() == 'PyPy':
+		def do_render(self, **kwargs):
+			# Make sure that only ASCII characters survive
+			ret = super(PDBRenderer, self).do_render(**kwargs)
+			ret = ret.encode('ascii', 'replace')
+			ret = ret.decode('ascii')
+			return ret
+
 
 renderer = PDBRenderer