Merge pull request #1157 from elebow/eruby-add-erubi-linter

[eruby] Add erubi linter

ale_linters/eruby/erubi.vim

@@ -0,0 +1,35 @@
+" Author: Eddie Lebow https://github.com/elebow
+" Description: eruby checker using `erubi`
+
+function! ale_linters#eruby#erubi#CheckErubi(buffer) abort
+    return 'ruby -r erubi/capture_end -e ' . ale#Escape('""')
+endfunction
+
+function! ale_linters#eruby#erubi#GetCommand(buffer, check_erubi_output) abort
+    let l:rails_root = ale#ruby#FindRailsRoot(a:buffer)
+
+    if (!empty(a:check_erubi_output))
+        " The empty command in CheckErubi returns nothing if erubi runs and
+        " emits an error if erubi is not present
+        return ''
+    endif
+
+    if empty(l:rails_root)
+        return 'ruby -r erubi/capture_end -e ' . ale#Escape('puts Erubi::CaptureEndEngine.new($stdin.read).src') . '< %t | ruby -c'
+    endif
+
+    " Rails-flavored eRuby does not comply with the standard as understood by
+    " Erubi, so we'll have to do some substitution. This does not reduce the
+    " effectiveness of the linter---the translated code is still evaluated.
+    return 'ruby -r erubi/capture_end -e ' . ale#Escape('puts Erubi::CaptureEndEngine.new($stdin.read.gsub(%{<%=},%{<%}), nil, %{-}).src') . '< %t | ruby -c'
+endfunction
+
+call ale#linter#Define('eruby', {
+\   'name': 'erubi',
+\   'executable': 'ruby',
+\   'command_chain': [
+\     {'callback': 'ale_linters#eruby#erubi#CheckErubi'},
+\     {'callback': 'ale_linters#eruby#erubi#GetCommand', 'output_stream': 'stderr'},
+\   ],
+\   'callback': 'ale#handlers#ruby#HandleSyntaxErrors',
+\})