Auto merge of #2329 - micbou:keyboard-interrupt, r=vheon

[READY] Handle keyboard interruption when evaluating Vim expression with user input

When evaluating a Vim expression in Python that involves code expecting user input (e.g. `input()`, `inputlist()`, `complete_check()`, etc.), if this evaluation is interrupted by the user (with `CTRL-C` for instance), Vim will pass the interruption to the Python interpreter which in turn will raise a `KeyboardInterrupt` exception. We don't want these exceptions to be displayed to the user (because the way Vim handles Python exceptions is really annoying) so we catch them where appropriate.

Fixes #2289.

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autoload/youcompleteme.vim

@@ -728,23 +728,8 @@ function! s:InvokeCompletion()
 endfunction
 
 
-exec s:python_until_eof
-def GetCompletionsInner():
-  request = ycm_state.GetCurrentCompletionRequest()
-  request.Start()
-  while not request.Done():
-    if bool( int( vim.eval( 'complete_check()' ) ) ):
-      return { 'words' : [], 'refresh' : 'always'}
-
-  results = base.AdjustCandidateInsertionText( request.Response() )
-  return { 'words' : results, 'refresh' : 'always' }
-EOF
-
-
 function! s:GetCompletions()
-  exec s:python_command "results = GetCompletionsInner()"
-  let results = s:Pyeval( 'results' )
-  return results
+  return s:Pyeval( 'ycm_state.GetCompletions()' )
 endfunction
 
 

python/ycm/vimsupport.py

@@ -506,7 +506,10 @@ def PresentDialog( message, choices, default_choice_index = 0 ):
     EscapeForVim( ToUnicode( message ) ),
     EscapeForVim( ToUnicode( "\n" .join( choices ) ) ),
     default_choice_index + 1 )
-  return int( vim.eval( to_eval ) ) - 1
+  try:
+    return GetIntValue( to_eval ) - 1
+  except KeyboardInterrupt:
+    return -1
 
 
 def Confirm( message ):
@@ -554,9 +557,9 @@ def SelectFromList( prompt, items ):
     # See :help input() for explanation of the use of inputsave() and inpput
     # restore(). It is done in try/finally in case vim.eval ever throws an
     # exception (such as KeyboardInterrupt)
-    selected = int( vim.eval( "inputlist( "
-                              + json.dumps( vim_items )
-                              + " )" ) ) - 1
+    selected = GetIntValue( "inputlist( " + json.dumps( vim_items ) + " )" ) - 1
+  except KeyboardInterrupt:
+    selected = -1
   finally:
     vim.eval( 'inputrestore()' )
 

python/ycm/youcompleteme.py

@@ -32,7 +32,7 @@ import signal
 import base64
 from subprocess import PIPE
 from tempfile import NamedTemporaryFile
-from ycm import paths, vimsupport
+from ycm import base, paths, vimsupport
 from ycmd import utils
 from ycmd import server_utils
 from ycmd.request_wrap import RequestWrap
@@ -234,6 +234,20 @@ class YouCompleteMe( object ):
     return self._latest_completion_request
 
 
+  def GetCompletions( self ):
+    request = self.GetCurrentCompletionRequest()
+    request.Start()
+    while not request.Done():
+      try:
+        if vimsupport.GetBoolValue( 'complete_check()' ):
+          return { 'words' : [], 'refresh' : 'always' }
+      except KeyboardInterrupt:
+        return { 'words' : [], 'refresh' : 'always' }
+
+    results = base.AdjustCandidateInsertionText( request.Response() )
+    return { 'words' : results, 'refresh' : 'always' }
+
+
   def SendCommandRequest( self, arguments, completer ):
     if self.IsServerAlive():
       return SendCommandRequest( arguments, completer )