Fix #3319 - Force modifications to buffers

1 files changed, 11 insertions, 0 deletions

diff --git a/autoload/ale/util.vim b/autoload/ale/util.vim
index 1f396377..05f11993 100644
--- a/autoload/ale/util.vim
+++ b/autoload/ale/util.vim
@@ -505,6 +505,13 @@ function! ale#util#SetBufferContents(buffer, lines) abort
     \   : a:lines
     let l:first_line_to_remove = len(l:new_lines) + 1
 
+    " We'll temporarily make a buffer modifiable, to force edits.
+    let l:modifiable = getbufvar(a:buffer, '&modifiable')
+
+    if !l:modifiable
+        call setbufvar(a:buffer, '&modifiable', 1)
+    endif
+
     " Use a Vim API for setting lines in other buffers, if available.
     if l:has_bufline_api
         call setbufline(a:buffer, 1, l:new_lines)
@@ -523,5 +530,9 @@ function! ale#util#SetBufferContents(buffer, lines) abort
         call setline(1, l:new_lines)
     endif
 
+    if !l:modifiable
+        call setbufvar(a:buffer, '&modifiable', 0)
+    endif
+
     return l:new_lines
 endfunction