From ca7fa31c619e9f259dd39eadc3b4b2c5bbaa4eba Mon Sep 17 00:00:00 2001
From: w0rp <devw0rp@gmail.com>
Date: Wed, 4 Jul 2018 08:52:08 +0100
Subject: [PATCH] Close #1690 - Respect the preview setting for completeopt

---
 autoload/ale/completion.vim                  |  6 +++++-
 test/completion/test_completion_events.vader | 19 ++++++++++++++++++-
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/autoload/ale/completion.vim b/autoload/ale/completion.vim
index 4823b00c..694cb655 100644
--- a/autoload/ale/completion.vim
+++ b/autoload/ale/completion.vim
@@ -134,7 +134,11 @@ function! s:ReplaceCompleteopt() abort
         let b:ale_old_completopt = &l:completeopt
     endif
 
-    let &l:completeopt = 'menu,menuone,preview,noselect,noinsert'
+    if &l:completeopt =~# 'preview'
+        let &l:completeopt = 'menu,menuone,preview,noselect,noinsert'
+    else
+        let &l:completeopt = 'menu,menuone,noselect,noinsert'
+    endif
 endfunction
 
 function! ale#completion#OmniFunc(findstart, base) abort
diff --git a/test/completion/test_completion_events.vader b/test/completion/test_completion_events.vader
index fbe18bb6..96182013 100644
--- a/test/completion/test_completion_events.vader
+++ b/test/completion/test_completion_events.vader
@@ -9,6 +9,8 @@ Before:
   let g:get_completions_called = 0
   let g:feedkeys_calls = []
 
+  let &l:completeopt = 'menu,menuone,preview,noselect,noinsert'
+
   runtime autoload/ale/util.vim
 
   function! ale#util#FeedKeys(string, mode) abort
@@ -95,6 +97,14 @@ Execute(ale#completion#Show() should remember the completeopt setting and replac
   call ale#completion#Show('Response', 'Parser')
 
   AssertEqual 'menu', b:ale_old_completopt
+  AssertEqual 'menu,menuone,noselect,noinsert', &l:completeopt
+
+Execute(ale#completion#Show() should set the preview option if it's set):
+  let &l:completeopt = 'menu,preview'
+
+  call ale#completion#Show('Response', 'Parser')
+
+  AssertEqual 'menu,preview', b:ale_old_completopt
   AssertEqual 'menu,menuone,preview,noselect,noinsert', &l:completeopt
 
 Execute(ale#completion#OmniFunc() should also remember the completeopt setting and replace it):
@@ -103,6 +113,14 @@ Execute(ale#completion#OmniFunc() should also remember the completeopt setting a
   call ale#completion#OmniFunc(0, '')
 
   AssertEqual 'menu', b:ale_old_completopt
+  AssertEqual 'menu,menuone,noselect,noinsert', &l:completeopt
+
+Execute(ale#completion#OmniFunc() should set the preview option if it's set):
+  let &l:completeopt = 'menu,preview'
+
+  call ale#completion#OmniFunc(0, '')
+
+  AssertEqual 'menu,preview', b:ale_old_completopt
   AssertEqual 'menu,menuone,preview,noselect,noinsert', &l:completeopt
 
 Execute(ale#completion#Show() should make the correct feedkeys() call):
@@ -127,7 +145,6 @@ Execute(ale#completion#Done() should restore old omnifunc values):
 
 Execute(ale#completion#Done() should restore the old completeopt setting):
   let b:ale_old_completopt = 'menu'
-  let &l:completeopt = 'menu,menuone,preview,noselect,noinsert'
 
   call ale#completion#Done()