Apply the autosuggestion as the first completion in the PTK completer

xonsh/ptk/completer.py

@@ -5,6 +5,7 @@ import builtins
 
 from prompt_toolkit.layout.dimension import LayoutDimension
 from prompt_toolkit.completion import Completer, Completion
+from prompt_toolkit.auto_suggest import AutoSuggestFromHistory
 
 
 class PromptToolkitCompleter(Completer):
@@ -13,22 +14,26 @@ class PromptToolkitCompleter(Completer):
     It just redirects requests to normal Xonsh completer.
     """
 
-    def __init__(self, completer, ctx):
-        """Takes instance of xonsh.completer.Completer and dict with context."""
+    def __init__(self, completer, ctx, shell):
+        """Takes instance of xonsh.completer.Completer, the xonsh execution
+        context, and the shell instance itself.
+        """
         self.completer = completer
         self.ctx = ctx
+        self.shell = shell
+        self.hist_suggester = AutoSuggestFromHistory()
 
     def get_completions(self, document, complete_event):
         """Returns a generator for list of completions."""
+        env = builtins.__xonsh_env__
         should_complete = (
             complete_event.completion_requested or
-            builtins.__xonsh_env__.get('UPDATE_COMPLETIONS_ON_KEYPRESS')
+            env.get('UPDATE_COMPLETIONS_ON_KEYPRESS')
             )
         #  Only generate completions when the user hits tab.
-        if should_complete:
-            if self.completer is None:
-                yield from []
-            else:
+        if not should_complete or self.completer is None:
+            return
+        # generate actual completions
         line = document.current_line.lstrip()
         line_ex = builtins.aliases.expand_alias(line)
 
@@ -37,31 +42,48 @@ class PromptToolkitCompleter(Completer):
                   if line[:endidx].rfind(' ') >= 0 else 0)
         prefix = line[begidx:endidx]
         expand_offset = len(line_ex) - len(line)
-
-                completions, l = self.completer.complete(prefix,
-                                                         line_ex,
+        # get normal completions
+        completions, l = self.completer.complete(prefix, line_ex,
                                                  begidx + expand_offset,
                                                  endidx + expand_offset,
                                                  self.ctx)
+        # completions from auto suggest
+        if env.get('AUTO_SUGGEST'):
+            sug_comp = self.suggestion_completion(document, line)
+            if sug_comp is None:
+                pass
+            elif len(completions) == 0:
+                completions = (sug_comp,)
+            else:
+                completions = (sug_comp,) + completions
+        # reserve space, if needed.
         if len(completions) <= 1:
             pass
         elif len(os.path.commonprefix(completions)) <= len(prefix):
             self.reserve_space()
-
         # Find common prefix (strip quoting)
-                c_prefix = os.path.commonprefix([a.strip('\'"')
-                                                for a in completions])
+        c_prefix = os.path.commonprefix([a.strip('\'"') for a in completions])
         # Find last split symbol, do not trim the last part
         while c_prefix:
             if c_prefix[-1] in r'/\.:@,':
                 break
             c_prefix = c_prefix[:-1]
-
+        # yield completions
         for comp in completions:
             # do not display quote
             disp = comp.strip('\'"')[len(c_prefix):]
             yield Completion(comp, -l, display=disp)
 
+    def suggestion_completion(self, document, line):
+        """Provides a completion based on the current auto-suggestion."""
+        cli = self.shell.prompter.cli
+        sug = self.hist_suggester.get_suggestion(cli, cli.current_buffer, document)
+        if sug is None:
+            return None
+        comp, _ , _ = sug.text.partition(' ')
+        _, _, prev = line.rpartition(' ')
+        return prev + comp
+
     def reserve_space(self):
         cli = builtins.__xonsh_shell__.shell.prompter.cli
         window = cli.application.layout.children[0].content.children[1]

xonsh/ptk/shell.py

@@ -38,7 +38,7 @@ class PromptToolkitShell(BaseShell):
         super().__init__(**kwargs)
         self.prompter = Prompter()
         self.history = PromptToolkitHistory()
-        self.pt_completer = PromptToolkitCompleter(self.completer, self.ctx)
+        self.pt_completer = PromptToolkitCompleter(self.completer, self.ctx, self)
         key_bindings_manager_args = {
             'enable_auto_suggest_bindings': True,
             'enable_search': True,