Issue #25660: Fix a unittest and rlcompleter when readline isn't available

1 files changed, 8 insertions, 4 deletions

diff --git a/Lib/rlcompleter.py b/Lib/rlcompleter.py
index 26f5920..401a626 100644
--- a/Lib/rlcompleter.py
+++ b/Lib/rlcompleter.py
@@ -75,9 +75,12 @@ class Completer:
 
         if not text.strip():
             if state == 0:
-                readline.insert_text('\t')
-                readline.redisplay()
-                return ''
+                if _readline_available:
+                    readline.insert_text('\t')
+                    readline.redisplay()
+                    return ''
+                else:
+                    return '\t'
             else:
                 return None
 
@@ -170,10 +173,11 @@ def get_class_members(klass):
 try:
     import readline
 except ImportError:
-    pass
+    _readline_available = False
 else:
     readline.set_completer(Completer().complete)
     # Release references early at shutdown (the readline module's
     # contents are quasi-immortal, and the completer function holds a
     # reference to globals).
     atexit.register(lambda: readline.set_completer(None))
+    _readline_available = True