diff --git a/autoload/ale/code_action.vim b/autoload/ale/code_action.vim
index 917190be..65db6246 100644
--- a/autoload/ale/code_action.vim
+++ b/autoload/ale/code_action.vim
@@ -16,13 +16,12 @@ endfunction
 function! ale#code_action#HandleCodeAction(code_action, options) abort
     let l:current_buffer = bufnr('')
     let l:changes = a:code_action.changes
-    let l:should_save = get(a:options, 'should_save')
 
     for l:file_code_edit in l:changes
         call ale#code_action#ApplyChanges(
         \   l:file_code_edit.fileName,
         \   l:file_code_edit.textChanges,
-        \   l:should_save,
+        \   a:options,
         \)
     endfor
 endfunction
@@ -63,29 +62,29 @@ function! s:ChangeCmp(left, right) abort
     return 0
 endfunction
 
-function! ale#code_action#ApplyChanges(filename, changes, should_save) abort
-    let l:current_buffer = bufnr('')
+function! ale#code_action#ApplyChanges(filename, changes, options) abort
+    let l:should_save = get(a:options, 'should_save')
+    let l:conn_id = get(a:options, 'conn_id')
+
+    let l:orig_buffer = bufnr('')
+
     " The buffer is used to determine the fileformat, if available.
     let l:buffer = bufnr(a:filename)
-    let l:is_current_buffer = l:buffer > 0 && l:buffer == l:current_buffer
 
-    if l:buffer > 0
-        let l:lines = getbufline(l:buffer, 1, '$')
-
-        " Add empty line if there's trailing newline, like readfile() does.
-        if getbufvar(l:buffer, '&eol')
-            let l:lines += ['']
-        endif
-    else
-        let l:lines = readfile(a:filename, 'b')
+    if l:buffer != l:orig_buffer
+        call ale#util#Execute('silent edit ' . a:filename)
+        let l:buffer = bufnr('')
     endif
 
-    if l:is_current_buffer
-        let l:pos = getpos('.')[1:2]
-    else
-        let l:pos = [1, 1]
+    let l:lines = getbufline(l:buffer, 1, '$')
+
+    " Add empty line if there's trailing newline, like readfile() does.
+    if getbufvar(l:buffer, '&eol')
+        let l:lines += ['']
     endif
 
+    let l:pos = getpos('.')[1:2]
+
     " Changes have to be sorted so we apply them from bottom-to-top
     for l:code_edit in reverse(sort(copy(a:changes), function('s:ChangeCmp')))
         let l:line = l:code_edit.start.line
@@ -155,46 +154,25 @@ function! ale#code_action#ApplyChanges(filename, changes, should_save) abort
         endif
     endfor
 
-    if l:buffer > 0
-        " Make sure ale#util#{Writefile,SetBufferContents} add trailing
-        " newline if and only if it should be added.
-        if l:lines[-1] is# '' && getbufvar(l:buffer, '&eol')
-            call remove(l:lines, -1)
-        else
-            call setbufvar(l:buffer, '&eol', 0)
-        endif
-    elseif exists('+fixeol') && &fixeol && l:lines[-1] is# ''
-        " Not in buffer, ale#util#Writefile can't check &eol and always adds
-        " newline if &fixeol: remove to prevent double trailing newline.
+    " Make sure to add a trailing newline if and only if it should be added.
+    if l:lines[-1] is# '' && getbufvar(l:buffer, '&eol')
         call remove(l:lines, -1)
-    endif
-
-    if a:should_save || l:buffer < 0
-        call ale#util#Writefile(l:buffer, l:lines, a:filename)
     else
-        call ale#util#SetBufferContents(l:buffer, l:lines)
+        call setbufvar(l:buffer, '&eol', 0)
     endif
 
-    if l:is_current_buffer
-        if a:should_save
-            call ale#util#Execute(':e!')
-        endif
+    call ale#util#SetBufferContents(l:buffer, l:lines)
 
-        call setpos('.', [0, l:pos[0], l:pos[1], 0])
+    call ale#lsp#NotifyForChanges(l:conn_id, l:buffer)
+
+    if l:should_save
+        call ale#util#Execute('silent w!')
     endif
 
-    if a:should_save && l:buffer > 0 && !l:is_current_buffer
-        " Set up a one-time use event that will delete itself to reload the
-        " buffer next time it's entered to view the changes made to it.
-        execute 'augroup ALECodeActionReloadGroup' . l:buffer
-            autocmd!
+    call setpos('.', [0, l:pos[0], l:pos[1], 0])
 
-            execute printf(
-            \   'autocmd BufEnter <buffer=%d>'
-            \       . ' call ale#code_action#ReloadBuffer()',
-            \   l:buffer
-            \)
-        augroup END
+    if l:orig_buffer != l:buffer && bufexists(l:orig_buffer)
+        call ale#util#Execute('silent buf ' . string(l:orig_buffer))
     endif
 endfunction
 
diff --git a/autoload/ale/organize_imports.vim b/autoload/ale/organize_imports.vim
index e2b1c0d2..a6e77863 100644
--- a/autoload/ale/organize_imports.vim
+++ b/autoload/ale/organize_imports.vim
@@ -1,6 +1,6 @@
 " Author: Jerko Steiner <jerko.steiner@gmail.com>
 " Description: Organize imports support for tsserver
-"
+
 function! ale#organize_imports#HandleTSServerResponse(conn_id, response) abort
     if get(a:response, 'command', '') isnot# 'organizeImports'
         return
@@ -17,7 +17,10 @@ function! ale#organize_imports#HandleTSServerResponse(conn_id, response) abort
     \       'description': 'Organize Imports',
     \       'changes': l:file_code_edits,
     \   },
-    \   {}
+    \   {
+    \       'conn_id': a:conn_id,
+    \       'should_save': !&hidden,
+    \   },
     \)
 endfunction
 
diff --git a/autoload/ale/rename.vim b/autoload/ale/rename.vim
index 9030618e..a722cc94 100644
--- a/autoload/ale/rename.vim
+++ b/autoload/ale/rename.vim
@@ -84,7 +84,8 @@ function! ale#rename#HandleTSServerResponse(conn_id, response) abort
     \       'changes': l:changes,
     \   },
     \   {
-    \       'should_save': 1,
+    \       'conn_id': a:conn_id,
+    \       'should_save': !&hidden,
     \   },
     \)
 endfunction
@@ -116,7 +117,8 @@ function! ale#rename#HandleLSPResponse(conn_id, response) abort
         \       'changes': l:changes,
         \   },
         \   {
-        \       'should_save': 1,
+        \       'conn_id': a:conn_id,
+        \       'should_save': !&hidden,
         \   },
         \)
     endif
diff --git a/doc/ale.txt b/doc/ale.txt
index 6dbfb6d0..348cffaf 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -1820,8 +1820,8 @@ g:ale_open_list                                               *g:ale_open_list*
     autocmd!
     autocmd QuitPre * if empty(&buftype) | lclose | endif
   augroup END
-<
 
+<
 g:ale_pattern_options                                   *g:ale_pattern_options*
 
   Type: |Dictionary|
@@ -3435,6 +3435,10 @@ ALERename                                                           *ALERename*
   The symbol where the cursor is resting will be the symbol renamed, and a
   prompt will open to request a new name.
 
+  The rename operation will save all modified buffers when `set nohidden` is
+  set, because that disables leaving unsaved buffers in the background. See
+  `:help hidden` for more details.
+
 ALEFileRename                                                   *ALEFileRename*
 
   Rename a file and fix imports using `tsserver`.
diff --git a/test/test_code_action.vader b/test/test_code_action.vader
index c613222c..80e2b1d8 100644
--- a/test/test_code_action.vader
+++ b/test/test_code_action.vader
@@ -1,4 +1,15 @@
 Before:
+  let g:notified_changes = []
+
+  runtime autoload/ale/lsp.vim
+
+  function! ale#lsp#NotifyForChanges(conn_id, buffer) abort
+    call add(g:notified_changes, {
+    \ 'conn_id': a:conn_id,
+    \ 'buffer': a:buffer
+    \})
+  endfunction
+
   Save g:ale_enabled
   let g:ale_enabled = 0
 
@@ -36,10 +47,10 @@ Before:
 
 After:
   " Close the extra buffers if we opened it.
-  if bufnr(g:file1) != -1
+  if bufnr(g:file1) != -1 && buflisted(bufnr(g:file1))
     execute ':bp! | :bd! ' . bufnr(g:file1)
   endif
-  if bufnr(g:file2) != -1
+  if bufnr(g:file2) != -1 && buflisted(bufnr(g:file2))
     execute ':bp! | :bd! ' . bufnr(g:file2)
   endif
 
@@ -50,12 +61,16 @@ After:
     call delete(g:file2)
   endif
 
+  unlet! g:notified_changes
+  " unlet! g:expected_notified_changes
   unlet! g:file1
   unlet! g:file2
   unlet! g:test
   unlet! g:changes
   delfunction WriteFileAndEdit
 
+  runtime autoload/ale/lsp.vim
+
   Restore
 
 
@@ -118,7 +133,7 @@ Execute(It should modify and save multiple files):
   \     }]
   \   }],
   \ },
-  \ {'should_save': 1},
+  \ {'should_save': 1, 'conn_id': 'test_conn'},
   \)
 
   AssertEqual [
@@ -140,6 +155,13 @@ Execute(It should modify and save multiple files):
   \ '',
   \], readfile(g:file2, 'b')
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(g:file1),
+  \}, {
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(g:file2),
+  \}], g:notified_changes
 
 Execute(Beginning of file can be modified):
   let g:test.text = [
@@ -166,7 +188,7 @@ Execute(Beginning of file can be modified):
   \      }],
   \   }]
   \ },
-  \ {'should_save': 1},
+  \ {'should_save': 1, 'conn_id': 'test_conn'},
   \)
 
   AssertEqual [
@@ -174,6 +196,11 @@ Execute(Beginning of file can be modified):
   \  'type B: number',
   \] + g:test.text + [''], readfile(g:file1, 'b')
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(g:file1),
+  \}], g:notified_changes
+
 
 Execute(End of file can be modified):
   let g:test.text = [
@@ -200,7 +227,7 @@ Execute(End of file can be modified):
   \     }],
   \   }]
   \ },
-  \ {'should_save': 1},
+  \ {'should_save': 1, 'conn_id': 'test_conn'},
   \)
 
   AssertEqual g:test.text + [
@@ -209,6 +236,11 @@ Execute(End of file can be modified):
   \  '',
   \], readfile(g:file1, 'b')
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(g:file1),
+  \}], g:notified_changes
+
 
 Execute(Current buffer contents will be reloaded):
   let g:test.text = [
@@ -238,7 +270,7 @@ Execute(Current buffer contents will be reloaded):
   \      }],
   \   }]
   \ },
-  \ {'should_save': 1},
+  \ {'should_save': 1, 'conn_id': 'test_conn'},
   \)
 
   AssertEqual [
@@ -251,6 +283,55 @@ Execute(Current buffer contents will be reloaded):
   \  'type B: number',
   \] + g:test.text, getbufline(g:test.buffer, 1, '$')
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(g:file1),
+  \}], g:notified_changes
+
+
+Execute(Unlisted buffer contents will be modified correctly):
+  let g:test.text = [
+  \ 'class Name {',
+  \ '  value: string',
+  \ '}',
+  \]
+  call writefile(g:test.text, g:file1, 'S')
+
+  execute 'edit ' . g:file1
+  let g:test.buffer = bufnr(g:file1)
+
+  execute 'bd'
+  AssertEqual bufnr(g:file1), g:test.buffer
+
+  call ale#code_action#HandleCodeAction(
+  \ {
+  \   'changes': [{
+  \      'fileName': g:file1,
+  \      'textChanges': [{
+  \        'start': {
+  \          'line': 1,
+  \          'offset': 1,
+  \        },
+  \        'end': {
+  \          'line': 1,
+  \          'offset': 1,
+  \        },
+  \        'newText': "type A: string\ntype B: number\n",
+  \      }],
+  \   }]
+  \ },
+  \ {'should_save': 1, 'conn_id': 'test_conn'},
+  \)
+
+  AssertEqual [
+  \  'type A: string',
+  \  'type B: number',
+  \] + g:test.text + [''], readfile(g:file1, 'b')
+
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(g:file1),
+  \}], g:notified_changes
 
 # Tests for cursor repositioning. In comments `=` designates change range, and
 # `C` cursor position
@@ -261,13 +342,32 @@ Execute(Cursor will not move when it is before text change):
   let g:test.changes = g:test.create_change(2, 3, 2, 8, 'value2')
 
   call setpos('.', [0, 1, 1, 0])
-  call ale#code_action#HandleCodeAction(g:test.changes, {'should_save': 1})
+  call ale#code_action#HandleCodeAction(g:test.changes, {
+  \ 'should_save': 1,
+  \ 'conn_id': 'test_conn',
+  \})
   AssertEqual [1, 1], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
   call setpos('.', [0, 2, 2, 0])
-  call ale#code_action#HandleCodeAction(g:test.changes, {'should_save': 1})
+  call ale#code_action#HandleCodeAction(g:test.changes, {
+  \ 'should_save': 1,
+  \ 'conn_id': 'test_conn',
+  \})
   AssertEqual [2, 2], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}, {
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 # ====C====
 Execute(Cursor column will move to the change end when cursor between start/end):
   let g:test.changes = g:test.create_change(2, 3, 2, 8, 'value2')
@@ -276,11 +376,34 @@ Execute(Cursor column will move to the change end when cursor between start/end)
     call WriteFileAndEdit()
     call setpos('.', [0, 2, r, 0])
     AssertEqual '  value: string', getline('.')
-    call ale#code_action#HandleCodeAction(g:test.changes, {'should_save': 1})
+    call ale#code_action#HandleCodeAction(g:test.changes, {
+    \ 'should_save': 1,
+    \ 'conn_id': 'test_conn',
+    \})
     AssertEqual '  value2: string', getline('.')
     AssertEqual [2, 9], getpos('.')[1:2]
   endfor
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}, {
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}, {
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}, {
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}, {
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}, {
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 
 # ====C
 Execute(Cursor column will move back when new text is shorter):
@@ -289,11 +412,18 @@ Execute(Cursor column will move back when new text is shorter):
   AssertEqual '  value: string', getline('.')
   call ale#code_action#HandleCodeAction(
   \ g:test.create_change(2, 3, 2, 8, 'val'),
-  \ {'should_save': 1},
-  \)
+  \ {
+  \   'should_save': 1,
+  \   'conn_id': 'test_conn',
+  \ })
   AssertEqual '  val: string', getline('.')
   AssertEqual [2, 6], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 
 # ==== C
 Execute(Cursor column will move forward when new text is longer):
@@ -302,10 +432,19 @@ Execute(Cursor column will move forward when new text is longer):
   call setpos('.', [0, 2, 8, 0])
   AssertEqual '  value: string', getline('.')
   call ale#code_action#HandleCodeAction(
-  \ g:test.create_change(2, 3, 2, 8, 'longValue'), {'should_save': 1})
+  \ g:test.create_change(2, 3, 2, 8, 'longValue'),
+  \ {
+  \   'should_save': 1,
+  \   'conn_id': 'test_conn',
+  \ })
   AssertEqual '  longValue: string', getline('.')
   AssertEqual [2, 12], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 # =========
 # =
 # C
@@ -314,10 +453,19 @@ Execute(Cursor line will move when updates are happening on lines above):
   call setpos('.', [0, 3, 1, 0])
   AssertEqual '}', getline('.')
   call ale#code_action#HandleCodeAction(
-  \ g:test.create_change(1, 1, 2, 1, "test\ntest\n"), {'should_save': 1})
+  \ g:test.create_change(1, 1, 2, 1, "test\ntest\n"),
+  \ {
+  \   'should_save': 1,
+  \   'conn_id': 'test_conn',
+  \ })
   AssertEqual '}', getline('.')
   AssertEqual [4, 1], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 
 # =========
 # =C
@@ -326,10 +474,19 @@ Execute(Cursor line and column will move when change on lines above and just bef
   call setpos('.', [0, 2, 2, 0])
   AssertEqual '  value: string', getline('.')
   call ale#code_action#HandleCodeAction(
-  \ g:test.create_change(1, 1, 2, 1, "test\ntest\n123"), {'should_save': 1})
+  \ g:test.create_change(1, 1, 2, 1, "test\ntest\n123"),
+  \ {
+  \   'should_save': 1,
+  \   'conn_id': 'test_conn',
+  \ })
   AssertEqual '123  value: string', getline('.')
   AssertEqual [3, 5], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 # =========
 # ======C==
 # =
@@ -338,10 +495,19 @@ Execute(Cursor line and column will move at the end of changes):
   call setpos('.', [0, 2, 10, 0])
   AssertEqual '  value: string', getline('.')
   call ale#code_action#HandleCodeAction(
-  \ g:test.create_change(1, 1, 3, 1, "test\n"), {'should_save': 1})
+  \ g:test.create_change(1, 1, 3, 1, "test\n"),
+  \ {
+  \   'should_save': 1,
+  \   'conn_id': 'test_conn',
+  \ })
   AssertEqual '}', getline('.')
   AssertEqual [2, 1], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 #      C ==
 # ===
 Execute(Cursor will not move when changes happening on lines >= cursor, but after cursor):
@@ -349,23 +515,42 @@ Execute(Cursor will not move when changes happening on lines >= cursor, but afte
   call setpos('.', [0, 2, 3, 0])
   AssertEqual '  value: string', getline('.')
   call ale#code_action#HandleCodeAction(
-  \ g:test.create_change(2, 10, 3, 1, "number\n"), {'should_save': 1})
+  \ g:test.create_change(2, 10, 3, 1, "number\n"),
+  \ {
+  \   'should_save': 1,
+  \   'conn_id': 'test_conn',
+  \ })
   AssertEqual '  value: number', getline('.')
   AssertEqual [2, 3], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 Execute(Cursor will not move when change covers entire file):
   call WriteFileAndEdit()
   call setpos('.', [0, 2, 3, 0])
   call ale#code_action#HandleCodeAction(
   \ g:test.create_change(1, 1, len(g:test.text) + 1, 1,
   \   join(g:test.text + ['x'], "\n")),
-  \ {'should_save': 1})
+  \ {
+  \   'should_save': 1,
+  \   'conn_id': 'test_conn',
+  \ })
   AssertEqual [2, 3], getpos('.')[1:2]
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 Execute(It should just modify file when should_save is set to v:false):
   call WriteFileAndEdit()
   let g:test.change = g:test.create_change(1, 1, 1, 1, "import { writeFile } from 'fs';\n")
-  call ale#code_action#HandleCodeAction(g:test.change, {})
+  call ale#code_action#HandleCodeAction(g:test.change, {
+  \ 'conn_id': 'test_conn',
+  \})
   AssertEqual 1, getbufvar(bufnr(''), '&modified')
   AssertEqual [
   \ 'import { writeFile } from ''fs'';',
@@ -374,6 +559,11 @@ Execute(It should just modify file when should_save is set to v:false):
   \ '}',
   \], getline(1, '$')
 
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
+
 Given typescript(An example TypeScript file):
   type Foo = {}
 
@@ -393,7 +583,14 @@ Execute():
   \ {'end': {'offset': 14, 'line': 9}, 'newText': 'foo', 'start': {'offset': 3, 'line': 9}},
   \]
 
-  call ale#code_action#ApplyChanges(expand('%:p'), g:changes, 0)
+  call ale#code_action#ApplyChanges(expand('%:p'), g:changes, {
+  \ 'conn_id': 'test_conn',
+  \})
+
+  AssertEqual [{
+  \ 'conn_id': 'test_conn',
+  \ 'buffer': bufnr(''),
+  \}], g:notified_changes
 
 Expect(The changes should be applied correctly):
   type Foo = {}
diff --git a/test/test_code_action_corner_cases.vader b/test/test_code_action_corner_cases.vader
index c44cf0ea..7cdbba8a 100644
--- a/test/test_code_action_corner_cases.vader
+++ b/test/test_code_action_corner_cases.vader
@@ -34,20 +34,16 @@ Before:
   Save &fileformats
   set fileformats=unix
 
-  " two files, one accessed through a buffer, the other using write/readfile only
-  let g:files = [tempname(), tempname()]
+  let g:file = tempname()
 
-  function! TestChanges(contents, changes, mode) abort
-    let l:file = g:files[a:mode is 'file' ? 0 : 1]
-    call writefile(split(a:contents, '\n', 1), l:file, 'bS')
-    if a:mode isnot 'file'
-      execute 'edit ' . l:file
-    endif
-    call ale#code_action#ApplyChanges(l:file, a:changes, a:mode isnot 'buffer')
-    if a:mode is 'buffer'
-      execute 'write ' . l:file
-    endif
-    return join(readfile(l:file, 'b'), "\n")
+  function! TestChanges(contents, changes) abort
+    call writefile(split(a:contents, '\n', 1), g:file, 'bS')
+
+    call ale#code_action#ApplyChanges(g:file, a:changes, {
+    \ 'should_save': 1,
+    \})
+
+    return join(readfile(g:file, 'b'), "\n")
   endfunction!
 
   function! MkPos(line, offset) abort
@@ -63,17 +59,15 @@ Before:
   endfunction!
 
 After:
-  for g:file in g:files
-    if bufnr(g:file) != -1
-      execute ':bp! | :bd! ' . bufnr(g:file)
-    endif
-    if filereadable(g:file)
-      call delete(g:file)
-    endif
-  endfor
-  unlet! g:files g:file
+  if bufnr(g:file) != -1
+    execute ':bp! | :bd! ' . bufnr(g:file)
+  endif
 
-  unlet! g:mode
+  if filereadable(g:file)
+    call delete(g:file)
+  endif
+
+  unlet! g:file
 
   delfunction TestChanges
   delfunction MkPos
@@ -83,97 +77,67 @@ After:
   Restore
 
 Execute(Preserve (no)eol at eof):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "noeol",    TestChanges("noeol",    [], g:mode)
-    AssertEqual "eol\n",    TestChanges("eol\n",    [], g:mode)
-    AssertEqual "eols\n\n", TestChanges("eols\n\n", [], g:mode)
-  endfor
-
-  " there doesn't seem to be a way to tell if a buffer is empty or contains one
-  " empty line :-(
-  AssertEqual "", TestChanges("", [], 'file')
+  AssertEqual "noeol",    TestChanges("noeol",    [])
+  AssertEqual "eol\n",    TestChanges("eol\n",    [])
+  AssertEqual "eols\n\n", TestChanges("eols\n\n", [])
 
 Execute(Respect fixeol):
   set fixeol
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    silent echo "vscode skip" | AssertEqual "noeol\n", TestChanges("noeol", [], g:mode)
-    silent echo "vscode skip" | AssertEqual "eol\n",   TestChanges("eol\n", [], g:mode)
-  endfor
+
+  silent echo "vscode skip" | AssertEqual "noeol\n", TestChanges("noeol", [])
+  silent echo "vscode skip" | AssertEqual "eol\n",   TestChanges("eol\n", [])
 
 Execute(Add/del eol at eof):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "addeol\n", TestChanges("addeol",   [MkInsert(MkPos(1, 7), "\n")], g:mode)
-    AssertEqual "deleol",   TestChanges("deleol\n", [MkDelete(MkPos(1, 7), MkPos(1, 8))], g:mode)
-  endfor
+  AssertEqual "addeol\n", TestChanges("addeol",   [MkInsert(MkPos(1, 7), "\n")])
+  AssertEqual "deleol",   TestChanges("deleol\n", [MkDelete(MkPos(1, 7), MkPos(1, 8))])
 
 Execute(One character insertions to first line):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "xabc\ndef1\nghi\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(1, 0), "x")], g:mode)
-    AssertEqual "xabc\ndef2\nghi\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(1, 1), "x")], g:mode)
-    AssertEqual "axbc\ndef3\nghi\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(1, 2), "x")], g:mode)
-    AssertEqual "abcx\ndef4\nghi\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(1, 4), "x")], g:mode)
-    AssertEqual "abc\nxdef5\nghi\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(1, 5), "x")], g:mode)
-    AssertEqual "abc\nxdef6\nghi\n", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(1, 6), "x")], g:mode)
-  endfor
+  AssertEqual "xabc\ndef1\nghi\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(1, 0), "x")])
+  AssertEqual "xabc\ndef2\nghi\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(1, 1), "x")])
+  AssertEqual "axbc\ndef3\nghi\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(1, 2), "x")])
+  AssertEqual "abcx\ndef4\nghi\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(1, 4), "x")])
+  AssertEqual "abc\nxdef5\nghi\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(1, 5), "x")])
+  AssertEqual "abc\nxdef6\nghi\n", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(1, 6), "x")])
 
 Execute(One character + newline insertions to first line):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "x\nabc\ndef1\nghi\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(1, 0), "x\n")], g:mode)
-    AssertEqual "x\nabc\ndef2\nghi\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(1, 1), "x\n")], g:mode)
-    AssertEqual "ax\nbc\ndef3\nghi\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(1, 2), "x\n")], g:mode)
-    AssertEqual "abcx\n\ndef4\nghi\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(1, 4), "x\n")], g:mode)
-    AssertEqual "abc\nx\ndef5\nghi\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(1, 5), "x\n")], g:mode)
-    AssertEqual "abc\nx\ndef6\nghi\n", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(1, 6), "x\n")], g:mode)
-  endfor
+  AssertEqual "x\nabc\ndef1\nghi\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(1, 0), "x\n")])
+  AssertEqual "x\nabc\ndef2\nghi\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(1, 1), "x\n")])
+  AssertEqual "ax\nbc\ndef3\nghi\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(1, 2), "x\n")])
+  AssertEqual "abcx\n\ndef4\nghi\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(1, 4), "x\n")])
+  AssertEqual "abc\nx\ndef5\nghi\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(1, 5), "x\n")])
+  AssertEqual "abc\nx\ndef6\nghi\n", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(1, 6), "x\n")])
 
 Execute(One character insertions near end):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "abc\ndef1\nghxi\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(3, 3), "x")], g:mode)
-    AssertEqual "abc\ndef2\nghix\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(3, 4), "x")], g:mode)
-    AssertEqual "abc\ndef3\nghi\nx", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(3, 5), "x")], g:mode)
-    AssertEqual "abc\ndef4\nghi\nx", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(3, 6), "x")], g:mode)
-    AssertEqual "abc\ndef5\nghi\nx", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(4, 1), "x")], g:mode)
-    AssertEqual "abc\ndef6\nghi\nx", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(4, 2), "x")], g:mode)
-    AssertEqual "abc\ndef7\nghi\nx", TestChanges("abc\ndef7\nghi\n", [MkInsert(MkPos(5, 1), "x")], g:mode)
-    AssertEqual "abc\ndef8\nghi\nx", TestChanges("abc\ndef8\nghi\n", [MkInsert(MkPos(5, 2), "x")], g:mode)
-  endfor
+  AssertEqual "abc\ndef1\nghxi\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(3, 3), "x")])
+  AssertEqual "abc\ndef2\nghix\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(3, 4), "x")])
+  AssertEqual "abc\ndef3\nghi\nx", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(3, 5), "x")])
+  AssertEqual "abc\ndef4\nghi\nx", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(3, 6), "x")])
+  AssertEqual "abc\ndef5\nghi\nx", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(4, 1), "x")])
+  AssertEqual "abc\ndef6\nghi\nx", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(4, 2), "x")])
+  AssertEqual "abc\ndef7\nghi\nx", TestChanges("abc\ndef7\nghi\n", [MkInsert(MkPos(5, 1), "x")])
+  AssertEqual "abc\ndef8\nghi\nx", TestChanges("abc\ndef8\nghi\n", [MkInsert(MkPos(5, 2), "x")])
 
 Execute(One character + newline insertions near end):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "abc\ndef1\nghx\ni\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(3, 3), "x\n")], g:mode)
-    AssertEqual "abc\ndef2\nghix\n\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(3, 4), "x\n")], g:mode)
-    AssertEqual "abc\ndef3\nghi\nx\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(3, 5), "x\n")], g:mode)
-    AssertEqual "abc\ndef4\nghi\nx\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(3, 6), "x\n")], g:mode)
-    AssertEqual "abc\ndef5\nghi\nx\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(4, 1), "x\n")], g:mode)
-    AssertEqual "abc\ndef6\nghi\nx\n", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(4, 2), "x\n")], g:mode)
-  endfor
+  AssertEqual "abc\ndef1\nghx\ni\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(3, 3), "x\n")])
+  AssertEqual "abc\ndef2\nghix\n\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(3, 4), "x\n")])
+  AssertEqual "abc\ndef3\nghi\nx\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(3, 5), "x\n")])
+  AssertEqual "abc\ndef4\nghi\nx\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(3, 6), "x\n")])
+  AssertEqual "abc\ndef5\nghi\nx\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(4, 1), "x\n")])
+  AssertEqual "abc\ndef6\nghi\nx\n", TestChanges("abc\ndef6\nghi\n", [MkInsert(MkPos(4, 2), "x\n")])
 
 Execute(Newline insertions near end):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "abc\ndef1\ngh\ni\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(3, 3), "\n")], g:mode)
-    AssertEqual "abc\ndef2\nghi\n\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(3, 4), "\n")], g:mode)
-    AssertEqual "abc\ndef3\nghi\n\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(3, 5), "\n")], g:mode)
-    AssertEqual "abc\ndef4\nghi\n\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(3, 6), "\n")], g:mode)
-    AssertEqual "abc\ndef5\nghi\n\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(4, 1), "\n")], g:mode)
-  endfor
+  AssertEqual "abc\ndef1\ngh\ni\n", TestChanges("abc\ndef1\nghi\n", [MkInsert(MkPos(3, 3), "\n")])
+  AssertEqual "abc\ndef2\nghi\n\n", TestChanges("abc\ndef2\nghi\n", [MkInsert(MkPos(3, 4), "\n")])
+  AssertEqual "abc\ndef3\nghi\n\n", TestChanges("abc\ndef3\nghi\n", [MkInsert(MkPos(3, 5), "\n")])
+  AssertEqual "abc\ndef4\nghi\n\n", TestChanges("abc\ndef4\nghi\n", [MkInsert(MkPos(3, 6), "\n")])
+  AssertEqual "abc\ndef5\nghi\n\n", TestChanges("abc\ndef5\nghi\n", [MkInsert(MkPos(4, 1), "\n")])
 
 Execute(Single char deletions):
-  for g:mode in ['save', 'file', 'buffer']
-    Log g:mode
-    AssertEqual "bc\ndef1\nghi\n",  TestChanges("abc\ndef1\nghi\n", [MkDelete(MkPos(1, 1), MkPos(1, 2))], g:mode)
-    AssertEqual "ab\ndef2\nghi\n",  TestChanges("abc\ndef2\nghi\n", [MkDelete(MkPos(1, 3), MkPos(1, 4))], g:mode)
-    AssertEqual "abcdef3\nghi\n",   TestChanges("abc\ndef3\nghi\n", [MkDelete(MkPos(1, 4), MkPos(1, 5))], g:mode)
-    AssertEqual "abcdef4\nghi\n",   TestChanges("abc\ndef4\nghi\n", [MkDelete(MkPos(1, 4), MkPos(1, 6))], g:mode)
-    AssertEqual "abc\ndef5\ngh\n",  TestChanges("abc\ndef5\nghi\n", [MkDelete(MkPos(3, 3), MkPos(3, 4))], g:mode)
-    AssertEqual "abc\ndef6\nghi",   TestChanges("abc\ndef6\nghi\n", [MkDelete(MkPos(3, 4), MkPos(3, 5))], g:mode)
-    AssertEqual "abc\ndef7\nghi",   TestChanges("abc\ndef7\nghi\n", [MkDelete(MkPos(3, 4), MkPos(3, 6))], g:mode)
-    AssertEqual "abc\ndef8\nghi\n", TestChanges("abc\ndef8\nghi\n", [MkDelete(MkPos(4, 1), MkPos(4, 2))], g:mode)
-  endfor
+  AssertEqual "bc\ndef1\nghi\n",  TestChanges("abc\ndef1\nghi\n", [MkDelete(MkPos(1, 1), MkPos(1, 2))])
+  AssertEqual "ab\ndef2\nghi\n",  TestChanges("abc\ndef2\nghi\n", [MkDelete(MkPos(1, 3), MkPos(1, 4))])
+  AssertEqual "abcdef3\nghi\n",   TestChanges("abc\ndef3\nghi\n", [MkDelete(MkPos(1, 4), MkPos(1, 5))])
+  AssertEqual "abcdef4\nghi\n",   TestChanges("abc\ndef4\nghi\n", [MkDelete(MkPos(1, 4), MkPos(1, 6))])
+  AssertEqual "abc\ndef5\ngh\n",  TestChanges("abc\ndef5\nghi\n", [MkDelete(MkPos(3, 3), MkPos(3, 4))])
+  AssertEqual "abc\ndef6\nghi",   TestChanges("abc\ndef6\nghi\n", [MkDelete(MkPos(3, 4), MkPos(3, 5))])
+  AssertEqual "abc\ndef7\nghi",   TestChanges("abc\ndef7\nghi\n", [MkDelete(MkPos(3, 4), MkPos(3, 6))])
+  AssertEqual "abc\ndef8\nghi\n", TestChanges("abc\ndef8\nghi\n", [MkDelete(MkPos(4, 1), MkPos(4, 2))])
diff --git a/test/test_code_action_python.vader b/test/test_code_action_python.vader
index 2aac1ec7..3c784816 100644
--- a/test/test_code_action_python.vader
+++ b/test/test_code_action_python.vader
@@ -10,7 +10,7 @@ Execute():
   \ {'end': {'offset': 15, 'line': 3}, 'newText': "    return c\n\n\ndef main():\n    c = func_qtffgsvi()\n", 'start': {'offset': 15, 'line': 3}}
   \]
 
-  call ale#code_action#ApplyChanges(expand('%:p'), g:changes, 0)
+  call ale#code_action#ApplyChanges(expand('%:p'), g:changes, {})
 
 Expect(The changes should be applied correctly):
   def func_qtffgsvi():
@@ -40,7 +40,7 @@ Execute():
   \ {'end': {'offset': 42, 'line': 8}, 'newText': "ivlpdpao(f)\n", 'start': {'offset': 33, 'line': 6}}
   \]
 
-  call ale#code_action#ApplyChanges(expand('%:p'), g:changes, 0)
+  call ale#code_action#ApplyChanges(expand('%:p'), g:changes, {})
 
 Expect(The changes should be applied correctly):
   import sys
diff --git a/test/test_organize_imports.vader b/test/test_organize_imports.vader
index 63973a54..87cd295a 100644
--- a/test/test_organize_imports.vader
+++ b/test/test_organize_imports.vader
@@ -59,7 +59,7 @@ Before:
 
   function! ale#code_action#HandleCodeAction(code_action, options) abort
     let g:handle_code_action_called = 1
-    Assert !get(a:options, 'should_save')
+    AssertEqual !&hidden, get(a:options, 'should_save')
     call add(g:code_actions, a:code_action)
   endfunction
 
diff --git a/test/test_rename.vader b/test/test_rename.vader
index 42bcfd95..4298715f 100644
--- a/test/test_rename.vader
+++ b/test/test_rename.vader
@@ -59,7 +59,7 @@ Before:
 
   function! ale#code_action#HandleCodeAction(code_action, options) abort
     let g:handle_code_action_called = 1
-    Assert get(a:options, 'should_save')
+    AssertEqual !&hidden, get(a:options, 'should_save', 0)
     call add(g:code_actions, a:code_action)
   endfunction