python: Move to separate file

hm/dev/pythonstartup.py

@@ -0,0 +1,47 @@
+#!/usr/bin/env python3
+
+import sys
+import os
+
+# From https://github.com/python/cpython/blob/v3.7.0b5/Lib/site.py#L436
+# Changing the history file
+def register_readline() -> None:
+    import atexit
+    try:
+        import readline
+        import rlcompleter
+    except ImportError:
+        return
+
+    # Reading the initialization (config) file may not be enough to set a
+    # completion key, so we set one first and then read the file.
+    readline_doc = getattr(readline, '__doc__', '')
+    if readline_doc is not None and 'libedit' in readline_doc:
+        readline.parse_and_bind('bind ^I rl_complete')
+    else:
+        readline.parse_and_bind('tab: complete')
+
+    try:
+        readline.read_init_file()
+    except OSError:
+        # An OSError here could have many causes, but the most likely one
+        # is that there's no .inputrc file (or .editrc file in the case of
+        # Mac OS X + libedit) in the expected location.  In that case, we
+        # want to ignore the exception.
+        pass
+
+    if readline.get_current_history_length() == 0:
+        # If no history was loaded, default to .python_history.
+        # The guard is necessary to avoid doubling history size at
+        # each interpreter exit when readline was already configured
+        # through a PYTHONSTARTUP hook, see:
+        # http://bugs.python.org/issue5845#msg198636
+        history = os.path.join(os.path.expanduser('~'),
+                               '.cache/python_history')
+        try:
+            readline.read_history_file(history)
+        except OSError:
+            pass
+        atexit.register(readline.write_history_file, history)
+
+sys.__interactivehook__ = register_readline