Auto merge of #1807 - micbou:canonical-response, r=vheon

Handle canonical response from subcommands

In continuation to PR #1805, when the ycmd server returns a canonical type (boolean, number, string, etc.), we should print it to the user.

For example, this applies to the `SolutionFile` C♯ subcommand which only returns a string (actually, this could be improved in the completer).

This also fixes a thrown exception when the response is not iterable (a number for example).

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python/ycm/client/command_request.py

@@ -63,15 +63,18 @@ class CommandRequest( BaseRequest ):
     if not self.Done() or self._response is None:
       return
 
-    if isinstance( self._response, bool ):
-      return self._HandleBooleanResponse()
-
     if self._is_goto_command:
       return self._HandleGotoResponse()
 
     if self._is_fixit_command:
       return self._HandleFixitResponse()
 
+    # If not a dictionary or a list, the response is necessarily a
+    # scalar: boolean, number, string, etc. In this case, we print
+    # it to the user.
+    if not isinstance( self._response, ( dict, list ) ):
+      return self._HandleBasicResponse()
+
     if 'message' in self._response:
       return self._HandleMessageResponse()
 
@@ -103,10 +106,8 @@ class CommandRequest( BaseRequest ):
                                    + " changes" )
 
 
-  def _HandleBooleanResponse( self ):
-    if self._response:
-      return vimsupport.EchoText( 'Yes' )
-    vimsupport.EchoText( 'No' )
+  def _HandleBasicResponse( self ):
+    vimsupport.EchoText( self._response )
 
 
   def _HandleMessageResponse( self ):