From 355f0f0e0c09569f0dba29a12be55075da4d16dc Mon Sep 17 00:00:00 2001
From: Ben Jackson <puremourning@gmail.com>
Date: Fri, 17 Jan 2020 00:02:24 +0000
Subject: [PATCH] Implement command line completion for watch/eval

---
 autoload/vimspector.vim                       |  5 +++-
 plugin/vimspector.vim                         |  4 +--
 .../vimspector/debug_adapter_connection.py    | 27 +++++++++++++++++++
 python3/vimspector/debug_session.py           | 20 ++++++++++++++
 4 files changed, 53 insertions(+), 3 deletions(-)

diff --git a/autoload/vimspector.vim b/autoload/vimspector.vim
index c3ead44..f2b39d5 100644
--- a/autoload/vimspector.vim
+++ b/autoload/vimspector.vim
@@ -121,7 +121,10 @@ function! vimspector#CompleteOutput( ArgLead, CmdLine, CursorPos ) abort
 endfunction
 
 function! vimspector#CompleteExpr( ArgLead, CmdLine, CursorPos ) abort
-  return []
+  return join( py3eval( '_vimspector_session.GetCompletionsSync( '
+                      \.'  vim.eval( "a:CmdLine" ),'
+                      \.'  int( vim.eval( "a:CursorPos" ) ) )' ),
+             \ "\n" )
 endfunction
 
 " Boilerplate {{{
diff --git a/plugin/vimspector.vim b/plugin/vimspector.vim
index 61c956a..0c71090 100644
--- a/plugin/vimspector.vim
+++ b/plugin/vimspector.vim
@@ -71,13 +71,13 @@ elseif s:mappings ==# 'HUMAN'
   nmap <F12>        <Plug>VimspectorStepOut
 endif
 
-command! -bar -nargs=1 -complete=customlist,vimspector#CompleteExpr
+command! -bar -nargs=1 -complete=custom,vimspector#CompleteExpr
       \ VimspectorWatch
       \ call vimspector#AddWatch( <f-args> )
 command! -bar -nargs=1 -complete=custom,vimspector#CompleteOutput
       \ VimspectorShowOutput
       \ call vimspector#ShowOutput( <f-args> )
-command! -bar -nargs=1 -complete=customlist,vimspector#CompleteExpr
+command! -bar -nargs=1 -complete=custom,vimspector#CompleteExpr
       \ VimspectorEval
       \ call vimspector#Evaluate( <f-args> )
 command! -bar
diff --git a/python3/vimspector/debug_adapter_connection.py b/python3/vimspector/debug_adapter_connection.py
index 73a4549..295b83d 100644
--- a/python3/vimspector/debug_adapter_connection.py
+++ b/python3/vimspector/debug_adapter_connection.py
@@ -65,6 +65,33 @@ class DebugAdapterConnection( object ):
     if not self._SendMessage( msg ):
       self._AbortRequest( request, 'Unable to send message' )
 
+
+  def DoRequestSync( self, msg, timeout = 5000 ):
+    result = {}
+
+    def handler( msg ):
+      result[ 'response' ] = msg
+
+    def failure_handler( reason, msg ):
+      result[ 'response' ] = msg
+      result[ 'exception' ] = RuntimeError( reason )
+
+    self.DoRequest( handler, msg, failure_handler, timeout )
+
+    bug_catcher = 1000
+    while not result and bug_catcher >= 0:
+      vim.command( 'sleep 10m' )
+      bug_catcher -= 10
+
+    if result.get( 'exception' ) is not None:
+      raise result[ 'exception' ]
+
+    if result.get( 'response' ) is None:
+      raise RuntimeError( "No response" )
+
+    return result[ 'response' ]
+
+
   def OnRequestTimeout( self, timer_id ):
     request_id = None
     for seq, request in self._outstanding_requests.items():
diff --git a/python3/vimspector/debug_session.py b/python3/vimspector/debug_session.py
index a4d801b..474e3d0 100644
--- a/python3/vimspector/debug_session.py
+++ b/python3/vimspector/debug_session.py
@@ -406,6 +406,26 @@ class DebugSession( object ):
   def GetOutputBuffers( self ):
     return self._outputView.GetCategories()
 
+  def GetCompletionsSync( self, text_line, column_in_bytes ):
+    if not self._server_capabilities.get( 'supportsCompletionsRequest' ):
+      return []
+
+    response = self._connection.DoRequestSync( {
+      'command': 'completions',
+      'arguments': {
+        'frameId': self._stackTraceView.GetCurrentFrame()[ 'id' ],
+        # TODO: encoding ? bytes/codepoints
+        'text': text_line,
+        'column': column_in_bytes
+      }
+    } )
+    # TODO:
+    #  - start / length
+    #  - sortText
+    return [ i.get( 'text' ) or i[ 'label' ]
+             for i in response[ 'body' ][ 'targets' ] ]
+
+
   def _SetUpUI( self ):
     vim.command( 'tabnew' )
     self._uiTab = vim.current.tabpage