Fix #741 - Set highlights for entire lines when signs are disabled

autoload/ale/highlight.vim

@@ -91,6 +91,22 @@ function! ale#highlight#UpdateHighlights() abort
         \   'matchaddpos(l:group, v:val)'
         \)
     endfor
+
+    " If highlights are enabled and signs are not enabled, we should still
+    " offer line highlights by adding a separate set of highlights.
+    if !g:ale_set_signs
+        for l:item in l:item_list
+            if l:item.type is# 'W'
+                let l:group = 'ALEWarningLine'
+            elseif l:item.type is# 'I'
+                let l:group = 'ALEInfoLine'
+            else
+                let l:group = 'ALEErrorLine'
+            endif
+
+            call matchaddpos(l:group, [l:item.lnum])
+        endfor
+    endif
 endfunction
 
 function! ale#highlight#BufferHidden(buffer) abort

doc/ale.txt

@@ -1149,6 +1149,17 @@ g:ale_set_highlights                                     *g:ale_set_highlights*
   |ALEStyleError|   - Items with `'type': 'E'` and `'sub_type': 'style'`
   |ALEStyleWarning| - Items with `'type': 'W'` and `'sub_type': 'style'`
 
+  When |g:ale_set_signs| is set to `0`, the following highlights for entire
+  lines will be set.
+
+  |ALEErrorLine|   - All items with `'type': 'E'`
+  |ALEWarningLine| - All items with `'type': 'W'`
+  |ALEInfoLine|    - All items with `'type': 'I'`
+
+  Vim can only highlight the characters up to the last column in a buffer for
+  match highlights, whereas the line highlights when signs are enabled will
+  run to the edge of the screen.
+
 
 g:ale_set_loclist                                           *g:ale_set_loclist*
 
@@ -1366,7 +1377,10 @@ ALEErrorLine                                                     *ALEErrorLine*
 
   Default: Undefined
 
-  The highlight for lines where error signs appear. See |g:ale_set_signs|.
+  The highlight for an entire line where errors appear. Only the first
+  line for a problem will be highlighted.
+
+  See |g:ale_set_signs| and |g:ale_set_highlights|.
 
 
 ALEErrorSign                                                     *ALEErrorSign*
@@ -1394,7 +1408,10 @@ ALEInfoLine                                                       *ALEInfoLine*
 
   Default: Undefined
 
-  The highlight for lines where info signs appear. See |g:ale_set_signs|.
+  The highlight for entire lines where info messages appear. Only the first
+  line for a problem will be highlighted.
+
+  See |g:ale_set_signs| and |g:ale_set_highlights|.
 
 
 ALEStyleError                                                   *ALEStyleError*
@@ -1436,7 +1453,10 @@ ALEWarningLine                                                 *ALEWarningLine*
 
   Default: Undefined
 
-  The highlight for lines where warning signs appear. See |g:ale_set_signs|.
+  The highlight for entire lines where warnings appear. Only the first line
+  for a problem will be highlighted.
+
+  See |g:ale_set_signs| and |g:ale_set_highlights|.
 
 
 ALEWarningSign                                                 *ALEWarningSign*

test/test_highlight_placement.vader

@@ -1,5 +1,6 @@
 Before:
   Save g:ale_enabled
+  Save g:ale_set_signs
 
   function! GenerateResults(buffer, output)
     return [
@@ -258,3 +259,23 @@ Execute(Highlights should be cleared when ALE is disabled):
   call ale#highlight#UpdateHighlights()
 
   AssertEqual [], GetMatchesWithoutIDs()
+
+Execute(Line highlights should be set when signs are disabled):
+  let g:ale_set_signs = 0
+
+  call ale#highlight#SetHighlights(bufnr(''), [
+  \ {'bufnr': bufnr(''), 'type': 'E', 'lnum': 1, 'col': 1},
+  \ {'bufnr': bufnr(''), 'type': 'W', 'lnum': 2, 'col': 1},
+  \ {'bufnr': bufnr(''), 'type': 'I', 'lnum': 3, 'col': 1},
+  \])
+
+  AssertEqual
+  \ [
+  \   {'group': 'ALEError', 'priority': 10, 'pos1': [1, 1, 1]},
+  \   {'group': 'ALEWarning', 'priority': 10, 'pos1': [2, 1, 1]},
+  \   {'group': 'ALEInfo', 'priority': 10, 'pos1': [3, 1, 1]},
+  \   {'group': 'ALEErrorLine', 'priority': 10, 'pos1': [1]},
+  \   {'group': 'ALEWarningLine', 'priority': 10, 'pos1': [2]},
+  \   {'group': 'ALEInfoLine', 'priority': 10, 'pos1': [3]},
+  \ ],
+  \ GetMatchesWithoutIDs()