fix(#395): fix race condition around buffer attachment (#399)

Author: tanvirtin

lua/vgit/git/GitBuffer.lua

@@ -230,6 +230,9 @@ function GitBuffer:exists()
   loop.free_textlock()
   if not self:is_valid() then return false end
 
+  loop.free_textlock()
+  if self:get_option('buftype') ~= '' then return false end
+
   loop.free_textlock()
   if not self:is_inside_git_dir() then return false end
 

lua/vgit/git/git_buffer_store.lua

@@ -1,6 +1,7 @@
 local loop = require('vgit.core.loop')
 local event = require('vgit.core.event')
 local utils = require('vgit.core.utils')
+local console = require('vgit.core.console')
 local git_repo = require('vgit.git.git_repo')
 local GitBuffer = require('vgit.git.GitBuffer')
 local assertion = require('vgit.core.assertion')
@@ -135,7 +136,13 @@ git_buffer_store.collect = function()
   local git_buffer = GitBuffer(0)
   git_buffer:sync()
 
-  if not git_buffer:exists() then return git_buffer_store.remove(git_buffer) end
+  local ok, result = pcall(git_buffer.exists, git_buffer)
+  if not ok then
+    git_buffer_store.remove(git_buffer)
+    console.debug.error(result)
+    return
+  end
+  if ok and not result then return git_buffer_store.remove(git_buffer) end
 
   if git_buffer_store.contains(git_buffer) then
     local existing_git_buffer = git_buffer_store.get(git_buffer)

lua/vgit/git/git_hunks.lua

@@ -57,7 +57,7 @@ function git_hunks.live(reponame, original_lines, current_lines)
 
       live_hunks[#live_hunks + 1] = hunk
     end,
-    algorithm = 'myers',
+    algorithm = git_hunks.algorithm,
   })
 
   return live_hunks