Replace ps1/ps2 with the default if values are not usable (fixes #896)

sebastinas · sebastinas · commit bc7ea75f21f1 · 2021-05-21T21:30:16.000+02:00
This is a workaround and should be replaced with a better solution in
the future.
diff --git a/bpython/curtsiesfrontend/repl.py b/bpython/curtsiesfrontend/repl.py
@@ -13,6 +13,7 @@
 from enum import Enum
 
 import blessings
+import cwcwidth
 import greenlet
 from curtsies import (
     FSArray,
@@ -275,6 +276,14 @@ def _find_module(self, fullname, path=None):
             return ImportLoader(self.watcher, loader)
 
 
+def _process_ps(ps, default_ps: str):
+    """Replace ps1/ps2 with the default if the user specified value contains control characters."""
+    if not isinstance(ps, str):
+        return ps
+
+    return ps if cwcwidth.wcswidth(ps) >= 0 else default_ps
+
+
 class BaseRepl(Repl):
     """Python Repl
 
@@ -2051,6 +2060,14 @@ def process():
 
         return "\n".join(process())
 
+    @property
+    def ps1(self):
+        return _process_ps(super().ps1, ">>> ")
+
+    @property
+    def ps2(self):
+        return _process_ps(super().ps2, "... ")
+
 
 def is_nop(char):
     return unicodedata.category(str(char)) == "Cc"
