Fix - don't switch windows/buffers to create a new hidden buffer

autoload/vimspector.vim

@@ -20,29 +20,47 @@ set cpoptions&vim
 " }}}
 
 
-call vimspector#internal#state#Reset()
+let s:enabled = vimspector#internal#state#Reset()
 
 function! vimspector#Launch() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.Start()
 endfunction
 
 function! vimspector#LaunchWithSettings( settings ) abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.Start( launch_variables = vim.eval( 'a:settings' ) )
 endfunction
 
 function! vimspector#Reset() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.Reset()
 endfunction
 
 function! vimspector#Restart() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.Restart()
 endfunction
 
 function! vimspector#ClearBreakpoints() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.ClearBreakpoints()
 endfunction
 
 function! vimspector#ToggleBreakpoint( ... ) abort
+  if !s:enabled
+    return
+  endif
   if a:0 == 0
     let options = {}
   else
@@ -52,6 +70,9 @@ function! vimspector#ToggleBreakpoint( ... ) abort
 endfunction
 
 function! vimspector#AddFunctionBreakpoint( function, ... ) abort
+  if !s:enabled
+    return
+  endif
   if a:0 == 0
     let options = {}
   else
@@ -62,42 +83,72 @@ function! vimspector#AddFunctionBreakpoint( function, ... ) abort
 endfunction
 
 function! vimspector#StepOver() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.StepOver()
 endfunction
 
 function! vimspector#StepInto() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.StepInto()
 endfunction
 
 function! vimspector#StepOut() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.StepOut()
 endfunction
 
 function! vimspector#Continue() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.Continue()
 endfunction
 
 function! vimspector#Pause() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.Pause()
 endfunction
 
 function! vimspector#Stop() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.Stop()
 endfunction
 
 function! vimspector#ExpandVariable() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.ExpandVariable()
 endfunction
 
 function! vimspector#DeleteWatch() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.DeleteWatch()
 endfunction
 
 function! vimspector#GoToFrame() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.ExpandFrameOrThread()
 endfunction
 
 function! vimspector#AddWatch( ... ) abort
+  if !s:enabled
+    return
+  endif
   if a:0 == 0
     let expr = input( 'Enter watch expression: ' )
   else
@@ -112,27 +163,42 @@ function! vimspector#AddWatch( ... ) abort
 endfunction
 
 function! vimspector#AddWatchPrompt( expr ) abort
+  if !s:enabled
+    return
+  endif
   stopinsert
   setlocal nomodified
   call vimspector#AddWatch( a:expr )
 endfunction
 
 function! vimspector#Evaluate( expr ) abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.ShowOutput( 'Console' )
   py3 _vimspector_session.EvaluateConsole( vim.eval( 'a:expr' ) )
 endfunction
 
 function! vimspector#EvaluateConsole( expr ) abort
+  if !s:enabled
+    return
+  endif
   stopinsert
   setlocal nomodified
   py3 _vimspector_session.EvaluateConsole( vim.eval( 'a:expr' ) )
 endfunction
 
 function! vimspector#ShowOutput( category ) abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.ShowOutput( vim.eval( 'a:category' ) )
 endfunction
 
 function! vimspector#ShowOutputInWindow( win_id, category ) abort
+  if !s:enabled
+    return
+  endif
   py3 __import__( 'vimspector',
         \         fromlist = [ 'output' ] ).output.ShowOutputInWindow(
         \           int( vim.eval( 'a:win_id' ) ),
@@ -140,16 +206,25 @@ function! vimspector#ShowOutputInWindow( win_id, category ) abort
 endfunction
 
 function! vimspector#ListBreakpoints() abort
+  if !s:enabled
+    return
+  endif
   py3 _vimspector_session.ListBreakpoints()
 endfunction
 
 function! vimspector#CompleteOutput( ArgLead, CmdLine, CursorPos ) abort
+  if !s:enabled
+    return
+  endif
   let buffers = py3eval( '_vimspector_session.GetOutputBuffers() '
                        \ . ' if _vimspector_session else []' )
   return join( buffers, "\n" )
 endfunction
 
 function! vimspector#CompleteExpr( ArgLead, CmdLine, CursorPos ) abort
+  if !s:enabled
+    return
+  endif
   return join( py3eval( '_vimspector_session.GetCompletionsSync( '
                       \.'  vim.eval( "a:CmdLine" ),'
                       \.'  int( vim.eval( "a:CursorPos" ) ) )'
@@ -158,6 +233,9 @@ function! vimspector#CompleteExpr( ArgLead, CmdLine, CursorPos ) abort
 endfunction
 
 function! vimspector#Install( ... ) abort
+  if !s:enabled
+    return
+  endif
   if a:0 < 1
     return
   endif
@@ -169,6 +247,9 @@ function! vimspector#Install( ... ) abort
 endfunction
 
 function! vimspector#CompleteInstall( ArgLead, CmdLine, CursorPos ) abort
+  if !s:enabled
+    return
+  endif
   return py3eval( '"\n".join('
                 \ .   '__import__( "vimspector", fromlist = [ "gadgets" ] )'
                 \ .   '.gadgets.GADGETS.keys() '

autoload/vimspector/internal/state.vim

@@ -25,11 +25,21 @@ if has( 'nvim' )
 endif
 
 function! vimspector#internal#state#Reset() abort
-    py3 << EOF
-import vim
-from vimspector import debug_session
-_vimspector_session = debug_session.DebugSession( vim.eval( 's:prefix' ) )
-EOF
+  try
+    py3 import vim
+    py3 _vimspector_session = __import__(
+          \ "vimspector",
+          \ fromlist=[ "debug_session" ] ).debug_session.DebugSession(
+          \   vim.eval( 's:prefix' ) )
+  catch /.*/
+    echohl WarningMsg
+    echom 'Exception while loading vimspector:' v:exception
+    echom 'Vimspector unavailable: Requires Vim compiled with Python 3.6'
+    echohl None
+    return v:false
+  endtry
+
+  return v:true
 endfunction
 
 function! vimspector#internal#state#GetAPIPrefix() abort

python3/vimspector/installer.py

@@ -90,7 +90,6 @@ def RunInstaller( api_prefix, *args, **kwargs ):
   vimspector_home = utils.GetVimString( vim.vars, 'vimspector_home' )
   vimspector_base_dir = utils.GetVimspectorBase()
 
-  # TODO: Translate the arguments to something more user-friendly than -- args
   global OUTPUT_VIEW
   if OUTPUT_VIEW:
     OUTPUT_VIEW.Reset()

python3/vimspector/output.py

@@ -52,6 +52,8 @@ def ShowOutputInWindow( win_id, category ):
 
 
 class OutputView( object ):
+  """Container for a 'tabbed' window of buffers that can be used to display
+  files or the output of commands."""
   def __init__( self, window, api_prefix ):
     self._window = window
     self._buffers = {}
@@ -144,75 +146,73 @@ class OutputView( object ):
                      file_name = None,
                      cmd = None,
                      completion_handler = None ):
-    win = self._window
-    if not win.valid:
-      # We need to borrow the current window
-      win = vim.current.window
+    if file_name is not None:
+      assert cmd is None
+      if install.GetOS() == "windows":
+        # FIXME: Can't display fiels in windows (yet?)
+        return
 
-    with utils.LetCurrentWindow( win ):
-      with utils.RestoreCurrentBuffer( win ):
+      cmd = [ 'tail', '-F', '-n', '+1', '--', file_name ]
 
-        if file_name is not None:
-          assert cmd is None
-          if install.GetOS() == "windows":
-            # FIXME: Can't display fiels in windows (yet?)
-            return
+    if cmd is not None:
+      out = utils.SetUpCommandBuffer(
+        cmd,
+        category,
+        self._api_prefix,
+        completion_handler = completion_handler )
+      self._buffers[ category ] = TabBuffer( out, len( self._buffers ) )
+      self._buffers[ category ].is_job = True
+      self._RenderWinBar( category )
+    else:
+      if category == 'Console':
+        name = 'vimspector.Console'
+      else:
+        name = 'vimspector.Output:{0}'.format( category )
 
-          cmd = [ 'tail', '-F', '-n', '+1', '--', file_name ]
+      tab_buffer = TabBuffer( utils.NewEmptyBuffer(), len( self._buffers ) )
+      self._buffers[ category ] = tab_buffer
 
-        if cmd is not None:
-          out = utils.SetUpCommandBuffer(
-            cmd,
-            category,
-            self._api_prefix,
-            completion_handler = completion_handler )
-          self._buffers[ category ] = TabBuffer( out, len( self._buffers ) )
-          self._buffers[ category ].is_job = True
-          self._RenderWinBar( category )
-        else:
-          vim.command( 'enew' )
-          tab_buffer = TabBuffer( vim.current.buffer, len( self._buffers ) )
-          self._buffers[ category ] = tab_buffer
-          if category == 'Console':
-            utils.SetUpPromptBuffer( tab_buffer.buf,
-                                     'vimspector.Console',
-                                     '> ',
-                                     'vimspector#EvaluateConsole' )
-          else:
-            utils.SetUpHiddenBuffer(
-              tab_buffer.buf,
-              'vimspector.Output:{0}'.format( category ) )
+      if category == 'Console':
+        utils.SetUpPromptBuffer( tab_buffer.buf,
+                                 name,
+                                 '> ',
+                                 'vimspector#EvaluateConsole' )
+      else:
+        utils.SetUpHiddenBuffer( tab_buffer.buf, name )
 
-          self._RenderWinBar( category )
+      self._RenderWinBar( category )
 
   def _RenderWinBar( self, category ):
     if not self._window.valid:
       return
 
-    tab_buffer = self._buffers[ category ]
+    with utils.LetCurrentWindow( self._window ):
+      tab_buffer = self._buffers[ category ]
 
-    try:
-      if tab_buffer.flag:
-        vim.command( 'nunmenu WinBar.{}'.format( utils.Escape( category ) ) )
-      else:
-        vim.command( 'nunmenu WinBar.{}*'.format( utils.Escape( category ) ) )
-    except vim.error as e:
-      # E329 means the menu doesn't exist; ignore that.
-      if 'E329' not in str( e ):
-        raise
+      try:
+        if tab_buffer.flag:
+          vim.command( 'nunmenu WinBar.{}'.format( utils.Escape( category ) ) )
+        else:
+          vim.command( 'nunmenu WinBar.{}*'.format( utils.Escape( category ) ) )
+      except vim.error as e:
+        # E329 means the menu doesn't exist; ignore that.
+        if 'E329' not in str( e ):
+          raise
 
-    vim.command( "nnoremenu  1.{0} WinBar.{1}{2} "
-                 ":call vimspector#ShowOutputInWindow( {3}, '{1}' )<CR>".format(
-                   tab_buffer.index,
-                   utils.Escape( category ),
-                   '*' if tab_buffer.flag else '',
-                   utils.WindowID( self._window ) ) )
+      vim.command(
+        "nnoremenu  1.{0} WinBar.{1}{2} "
+        ":call vimspector#ShowOutputInWindow( {3}, '{1}' )<CR>".format(
+          tab_buffer.index,
+          utils.Escape( category ),
+          '*' if tab_buffer.flag else '',
+          utils.WindowID( self._window ) ) )
 
   def GetCategories( self ):
     return list( self._buffers.keys() )
 
 
 class DAPOutputView( OutputView ):
+  """Specialised OutputView which adds the DAP Console (REPL)"""
   def __init__( self, *args ):
     super().__init__( *args )
 

python3/vimspector/utils.py

@@ -52,6 +52,12 @@ def BufferForFile( file_name ):
   return vim.buffers[ BufferNumberForFile( file_name ) ]
 
 
+def NewEmptyBuffer():
+  bufnr = int( vim.eval( 'bufadd("")' ) )
+  Call( 'bufload', bufnr )
+  return vim.buffers[ bufnr ]
+
+
 def WindowForBuffer( buf ):
   for w in vim.current.tabpage.windows:
     if w.buffer == buf:
@@ -353,6 +359,7 @@ def AskForInput( prompt, default_value = None ):
 
 
 def AppendToBuffer( buf, line_or_lines, modified=False ):
+  line = 1
   try:
     # After clearing the buffer (using buf[:] = None) there is always a single
     # empty line in the buffer object and no "is empty" method.