From 0938d72a8c3097d2b83b8e7e5f7d9cd35c87edcd Mon Sep 17 00:00:00 2001
From: Ben Jackson <puremourning@gmail.com>
Date: Sat, 11 Jul 2020 22:00:36 +0100
Subject: [PATCH] Re-use a window if we can, as it's more efficient; don't wipe
 out the generated code buffers in case the code window gets used for
 temporary buffer switch

---
 python3/vimspector/stack_trace.py |  9 ++++++++-
 python3/vimspector/utils.py       | 28 ++++++++++++++++++++++++----
 2 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/python3/vimspector/stack_trace.py b/python3/vimspector/stack_trace.py
index 4504d10..0afeb81 100644
--- a/python3/vimspector/stack_trace.py
+++ b/python3/vimspector/stack_trace.py
@@ -35,6 +35,7 @@ class StackTraceView( object ):
 
     self._threads = []
     self._sources = {}
+    self._scratch_buffers = []
 
     utils.SetUpHiddenBuffer( self._buf, 'vimspector.StackTrace' )
 
@@ -82,6 +83,11 @@ class StackTraceView( object ):
   def Reset( self ):
     self.Clear()
     utils.CleanUpHiddenBuffer( self._buf )
+    for b in self._scratch_buffers:
+      utils.CleanUpHiddenBuffer( b )
+
+    self._scratch_buffers = []
+    self._buf = None
 
   def LoadThreads( self, infer_current_frame ):
     pending_request = False
@@ -290,7 +296,8 @@ class StackTraceView( object ):
         self._logger.debug( "Received source %s: %s", buf_name, msg )
 
         buf = utils.BufferForFile( buf_name )
-        utils.SetUpScratchBuffer( buf, buf_name )
+        self._scratch_buffers.append( buf )
+        utils.SetUpHiddenBuffer( buf, buf_name )
         source[ 'path' ] = buf_name
         with utils.ModifiableScratchBuffer( buf ):
           utils.SetBufferContents( buf, msg[ 'body' ][ 'content' ] )
diff --git a/python3/vimspector/utils.py b/python3/vimspector/utils.py
index 03dbb4d..9fc1206 100644
--- a/python3/vimspector/utils.py
+++ b/python3/vimspector/utils.py
@@ -52,6 +52,14 @@ def BufferForFile( file_name ):
   return vim.buffers[ BufferNumberForFile( file_name ) ]
 
 
+def WindowForBuffer( buf ):
+  for w in vim.current.tabpage.windows:
+    if w.buffer == buf:
+      return w
+
+  return None
+
+
 def OpenFileInCurrentWindow( file_name ):
   buffer_number = BufferNumberForFile( file_name )
   try:
@@ -190,6 +198,18 @@ def RestoreCurrentBuffer( window ):
       vim.current.buffer = old_buffer
 
 
+@contextlib.contextmanager
+def AnyWindowForBuffer( buf ):
+  # Only checks the current tab page, which is what we want
+  current_win = WindowForBuffer( buf )
+  if current_win is not None:
+    with LetCurrentWindow( current_win ):
+      yield
+  else:
+    with LetCurrentBuffer( buf ):
+      yield
+
+
 @contextlib.contextmanager
 def LetCurrentWindow( window ):
   with RestoreCurrentWindow():
@@ -566,11 +586,11 @@ def SetSyntax( current_syntax, syntax, *args ):
   if current_syntax == syntax:
     return
 
+  # We use set syn= because just setting vim.Buffer.options[ 'syntax' ]
+  # doesn't actually trigger the Syntax autocommand, and i'm not sure that
+  # 'doautocmd Syntax' is the right solution or not
   for buf in args:
-    with LetCurrentBuffer( buf ):
-      # We use set syn= because just setting vim.Buffer.options[ 'syntax' ]
-      # doesn't actually trigger the Syntax autocommand, and i'm not sure that
-      # 'doautocmd Syntax' is the right solution or not
+    with AnyWindowForBuffer( buf ):
       vim.command( 'set syntax={}'.format( Escape( syntax ) ) )
 
   return syntax