Option to open lists vertically (#1381)

* Add configuration option to open lists vertically

* Add tests, clean up vertical list config

* Vertical list option cleanup

* Use is# for tests
* Order properties in documentation alphabetically

test/test_ale_info.vader

@@ -66,6 +66,7 @@ Before:
   \  'let g:ale_linters = {}',
   \  'let g:ale_linters_explicit = 0',
   \  'let g:ale_list_window_size = 10',
+  \  'let g:ale_list_vertical = 0',
   \  'let g:ale_loclist_msg_format = ''%code: %%s''',
   \  'let g:ale_max_buffer_history_size = 20',
   \  'let g:ale_max_signs = -1',

test/test_list_opening.vader

@@ -5,6 +5,7 @@ Before:
   Save g:ale_open_list
   Save g:ale_keep_list_window_open
   Save g:ale_list_window_size
+  Save g:ale_list_vertical
   Save g:ale_buffer_info
   Save g:ale_set_lists_synchronously
 
@@ -13,6 +14,7 @@ Before:
   let g:ale_open_list = 0
   let g:ale_keep_list_window_open = 0
   let g:ale_list_window_size = 10
+  let g:ale_list_vertical = 0
   let g:ale_set_lists_synchronously = 1
 
   let g:loclist = [
@@ -33,16 +35,29 @@ Before:
     return 0
   endfunction
 
+  " If the window is vertical, window size should match column size/width
+  function GetQuickfixIsVertical(cols) abort
+    for l:win in range(1, winnr('$'))
+        if getwinvar(l:win, '&buftype') is# 'quickfix'
+            return winwidth(l:win) == a:cols
+        endif
+    endfor
+
+    return 0
+  endfunction
+
 After:
   Restore
 
   unlet! g:loclist
+  unlet! b:ale_list_vertical
   unlet! b:ale_list_window_size
   unlet! b:ale_open_list
   unlet! b:ale_keep_list_window_open
   unlet! b:ale_save_event_fired
 
   delfunction GetQuickfixHeight
+  delfunction GetQuickfixIsVertical
 
   " Close quickfix window after every execute block
   lcl
@@ -98,6 +113,24 @@ Execute(The quickfix window height should be correct for the loclist with buffer
 
   AssertEqual 8, GetQuickfixHeight()
 
+Execute(The quickfix window should be vertical for the loclist with appropriate variables):
+  let g:ale_open_list = 1
+  let b:ale_list_window_size = 8
+  let b:ale_list_vertical = 1
+
+  call ale#list#SetLists(bufnr('%'), g:loclist)
+
+  AssertEqual 1, GetQuickfixIsVertical(b:ale_list_window_size)
+
+Execute(The quickfix window should be horizontal for the loclist with appropriate variables):
+  let g:ale_open_list = 1
+  let b:ale_list_window_size = 8
+  let b:ale_list_vertical = 0
+
+  call ale#list#SetLists(bufnr('%'), g:loclist)
+
+  AssertEqual 0, GetQuickfixIsVertical(b:ale_list_window_size)
+
 Execute(The quickfix window should stay open for just the loclist):
   let g:ale_open_list = 1
   let g:ale_keep_list_window_open = 1
@@ -167,6 +200,24 @@ Execute(The quickfix window height should be correct for the quickfix list with
 
   AssertEqual 8, GetQuickfixHeight()
 
+Execute(The quickfix window should be vertical for the quickfix with appropriate variables):
+  let g:ale_open_list = 1
+  let b:ale_list_window_size = 8
+  let b:ale_list_vertical = 1
+
+  call ale#list#SetLists(bufnr('%'), g:loclist)
+
+  AssertEqual 1, GetQuickfixIsVertical(b:ale_list_window_size)
+
+Execute(The quickfix window should be horizontal for the quickfix with appropriate variables):
+  let g:ale_open_list = 1
+  let b:ale_list_window_size = 8
+  let b:ale_list_vertical = 0
+
+  call ale#list#SetLists(bufnr('%'), g:loclist)
+
+  AssertEqual 0, GetQuickfixIsVertical(b:ale_list_window_size)
+
 Execute(The buffer ale_open_list option should be respected):
   let b:ale_open_list = 1