Improve auto completion for an arbitrary name using a given external …

…script (#296)

* Register auto completion for an arbitrary name using a given external script

* Add a space to indent with a multiple of four

* Add documentation of auto completion for an arbitrary name using a given external script

* Generate dynamically name of completion function in bash if necessary

README.rst

@@ -282,6 +282,17 @@ or create new completion file, e.g::
 
     register-python-argcomplete --shell fish ~/.config/fish/completions/my-awesome-script.fish
 
+External argcomplete script
+---------------------------
+To register an argcomplete script for an arbitrary name, the ``--external-argcomplete-script`` argument of the ``register-python-argcomplete`` script can be used::
+
+    eval "$(register-python-argcomplete --external-argcomplete-script /path/to/script arbitrary-name)"
+
+This allows, for example, to use the auto completion functionality of argcomplete for an application not written in Python. 
+The command line interface of this program must be additionally implemented in a Python script with argparse and argcomplete and whenever the application is called the registered external argcomplete script is used for auto completion.
+
+This option can also be used in combination with the other supported shells.
+
 Python Support
 --------------
 Argcomplete requires Python 2.7 or 3.5+.

argcomplete/shell_integration.py

@@ -16,7 +16,7 @@
     fi
 }
 
-_python_argcomplete() {
+_python_argcomplete%(function_suffix)s() {
     local IFS=$'\013'
     local SUPPRESS_SPACE=0
     if compopt +o nospace 2> /dev/null; then
@@ -36,7 +36,7 @@
         compopt -o nospace
     fi
 }
-complete %(complete_opts)s -F _python_argcomplete %(executables)s
+complete %(complete_opts)s -F _python_argcomplete%(function_suffix)s %(executables)s
 '''
 
 tcshcode = '''\
@@ -86,10 +86,14 @@ def shellcode(executables, use_defaults=True, shell='bash', complete_arguments=N
     if shell == 'bash':
         quoted_executables = [quote(i) for i in executables]
         executables_list = " ".join(quoted_executables)
-        if not argcomplete_script:
-            argcomplete_script = '$1'
+        script = argcomplete_script
+        if script:
+            function_suffix = '_' + script
+        else:
+            script = '$1'
+            function_suffix = ''
         code = bashcode % dict(complete_opts=complete_options, executables=executables_list,
-                               argcomplete_script=argcomplete_script)
+                               argcomplete_script=script, function_suffix=function_suffix)
     else:
         code = ""
         for executable in executables: