skip pyreadline dependency on Windows with Python 3.9+

humanfriendly/prompts.py

@@ -341,7 +341,11 @@ def prepare_friendly_prompts():
     This function is called by the other functions in this module to enable
     user friendly prompts.
     """
-    import readline  # NOQA
+    try:
+        import readline  # NOQA
+    except ImportError:
+        # might not be available on Windows if pyreadline isn't installed
+        pass
 
 
 def retry_limit(limit=MAX_ATTEMPTS):

setup.py

@@ -49,7 +49,9 @@ def get_install_requires():
         if sys.version_info.major == 2:
             install_requires.append('monotonic')
         if sys.platform == 'win32':
-            install_requires.append('pyreadline')
+            # pyreadline isn't compatible with Python 3.9+
+            # https://github.com/pyreadline/pyreadline/issues/65
+            install_requires.append('pyreadline ; python_version<"3.9"')
     return sorted(install_requires)
 
 
@@ -63,7 +65,9 @@ def get_extras_require():
         ])
         extras_require[expression] = ['monotonic']
         # Conditional `pyreadline' dependency.
-        expression = ':sys_platform == "win32"'
+        # pyreadline isn't compatible with Python 3.9+
+        # https://github.com/pyreadline/pyreadline/issues/65
+        expression = ':sys_platform == "win32" and python_version<"3.9"'
         extras_require[expression] = 'pyreadline'
     return extras_require