Merge pull request #2563 from dcyriller/fixer-prettier-glimmer

prettier: Support experimental languages (Handlebars)

test/fixers/test_prettier_fixer_callback.vader

@@ -280,6 +280,20 @@ Execute(Should set --parser based on first filetype of multiple filetypes):
   \     . ' --stdin-filepath %s --stdin',
   \ }
 
+Execute(Should set --parser for experimental language, Handlebars):
+  call ale#test#SetFilename('../prettier-test-files/testfile.hbs')
+
+  set filetype=html.handlebars
+
+  GivenCommandOutput ['1.6.0']
+  AssertFixer
+  \ {
+  \   'command': ale#path#CdString(expand('%:p:h'))
+  \     . ale#Escape(g:ale_javascript_prettier_executable)
+  \     . ' --parser glimmer'
+  \     . ' --stdin-filepath %s --stdin',
+  \ }
+
 Execute(The prettier_d post-processor should permit regular JavaScript content):
   AssertEqual
   \ [