Added back in preference for gnureadline if it is present

Now that the crash bug in the gnureadline Python module which statically links against a compatible version of GNU Readline has been fixed for macOS, we added back in the top-level import boilerplate to prefer it if it is available.

Also updated some documentation in relation to getting readline installed for macOS.

1 files changed, 9 insertions, 5 deletions

diff --git a/cmd2.py b/cmd2.py
index 525c0dac..8f137aaf 100755
--- a/cmd2.py
+++ b/cmd2.py
@@ -88,13 +88,17 @@ try:
 except ImportError:
     ipython_available = False
 
-# Try to import readline, but allow failure for convenience in Windows unit testing
-# Note: If this actually fails, you should install readline on Linux or Mac or pyreadline on Windows
+# Prefer statically linked gnureadline if available (for macOS compatibility due to issues with libedit)
 try:
-    # noinspection PyUnresolvedReferences
-    import readline
+    import gnureadline as readline
 except ImportError:
-    pass
+    # Try to import readline, but allow failure for convenience in Windows unit testing
+    # Note: If this actually fails, you should install readline on Linux or Mac or pyreadline on Windows
+    try:
+        # noinspection PyUnresolvedReferences
+        import readline
+    except ImportError:
+        pass
 
 # BrokenPipeError and FileNotFoundError exist only in Python 3. Use IOError for Python 2.
 if six.PY3: