Overhaul for new version

1 files changed, 105 insertions, 23 deletions

diff --git a/plugin/big_file_options.vim b/plugin/big_file_options.vim
index 90fc27d..a2df77b 100644
--- a/plugin/big_file_options.vim
+++ b/plugin/big_file_options.vim
@@ -13,45 +13,127 @@ if !has('autocmd') || v:version < 600
 endif
 let g:loaded_big_file_options = 1
 
-" Declare function for turning off slow options
-function! s:BigFileOptions()
-
-  " Don't do anything if the buffer size is under the threshold
-  let l:size = exists('g:big_file_options_size')
-        \ ? g:big_file_options_size
+" Wrapper function to get the configured size limit, default to 10 MiB
+function! s:Limit()
+  let l:limit = exists('g:big_file_options_limit')
+        \ ? g:big_file_options_limit
         \ : 10 * 1024 * 1024
-  if line2byte(line('$') + 1) <= l:size
+  return l:limit
+endfunction
+
+" If we can use filesize to detect the big file early, we should
+function! s:CheckPre(filename)
+
+  " Try and get filesize, bail out if we can't
+  let l:size = getfsize(a:filename)
+  if l:size == -1
     return
   endif
 
-  " Turn off backups, swap files, and undo files
-  setlocal nobackup
-  setlocal nowritebackup
+  " Set the buffer's big flag to whether the file is verifiably outsize
+  let b:big_file_options_big = l:size == -2 || l:size > s:Limit()
+
+  " If we found it's a big file, call the early options set
+  if b:big_file_options_big
+    call s:SetPre()
+  endif
+
+endfunction
+
+" If it's still indeterminate (stdin read?), try to check the buffer size
+" itself
+function! s:CheckPost()
+
+  " The BufReadPre hook couldn't tell how big the file was; we'll examine it
+  " now it's loaded into the buffer instead
+  if !exists('b:big_file_options_big')
+
+    " Test buffer size, bail if that doesn't work either
+    let l:size = line2byte(line('$') + 1)
+    if l:size == -1
+      return
+    endif
+
+    " Flag the buffer's oversize status, if it's positive, we'll catch up and
+    " run the early options set now
+    let b:big_file_options_big = l:size > s:Limit()
+    if b:big_file_options_big
+      call s:SetPre()
+    endif
+
+  endif
+
+  " If the buffer size is verifiably over the threshold, run the late options
+  " set
+  if b:big_file_options_big
+    call s:SetPost()
+  endif
+
+endfunction
+
+" These options can and should be set as early as possible
+function! s:SetPre()
+
+  " These are always set
   setlocal noswapfile
+  setlocal undolevels=-1
   if has('persistent_undo')
     setlocal noundofile
   endif
 
-  " Limit the number of columns of syntax highlighting
-  let l:synmaxcol = exists('g:big_file_options_synmaxcol')
-        \ ? g:big_file_options_synmaxcol
-        \ : 256
-  if exists('+synmaxcol') && &l:synmaxcol > l:synmaxcol
-    let &l:synmaxcol = l:synmaxcol
+  " Decide whether to set readonly options
+  let l:readonly = exists('g:big_file_options_readonly')
+        \ ? g:big_file_options_readonly
+        \ : 1
+  if l:readonly
+    setlocal buftype=nowrite
+    setlocal nomodifiable
+    setlocal readonly
   endif
 
-  " Disable syntax highlighting if configured to do so
-  let l:syntax = exists('g:big_file_options_syntax')
-        \ ? g:big_file_options_syntax
-        \ : 0
-  if !l:syntax
-    setlocal syntax=OFF
+endfunction
+
+" These options need to be set later, after the buffer has loaded
+function! s:SetPost()
+
+  " Force filetype off
+  setlocal filetype=NONE
+
+  " Syntax features
+  if has('syntax')
+
+    " Disable syntax highlighting if configured
+    let l:syntax = exists('g:big_file_options_syntax')
+          \ ? g:big_file_options_syntax
+          \ : 0
+    if !l:syntax
+      setlocal syntax=OFF
+    endif
+
+    " Force maximum syntax columns down if configured
+    if exists('+synmaxcol')
+      let l:synmaxcol = exists('g:big_file_options_synmaxcol')
+            \ ? g:big_file_options_synmaxcol
+            \ : 256
+      if exists('+synmaxcol') && &synmaxcol > l:synmaxcol
+        let &l:synmaxcol = l:synmaxcol
+      endif
+    endif
+
   endif
 
+  " Tell the user what we've done
+  echomsg 'Big file detected, set appropriate options'
+
 endfunction
 
 " Define autocmd for calling to check filesize
 augroup big_file_options
   autocmd!
-  autocmd BufReadPost * call s:BigFileOptions()
+  autocmd BufReadPre,StdinReadPre
+        \ *
+        \ call s:CheckPre(expand('<afile>'))
+  autocmd BufReadPost,StdinReadPost
+        \ *
+        \ call s:CheckPost()
 augroup end