Correctly checks for character before GFM input char

It must not be letter or number to work

app/assets/javascripts/gfm_auto_complete.js.coffee

@@ -43,6 +43,17 @@ GitLab.GfmAutoComplete =
         @at
       else
         value
+    matcher: (flag, subtext, should_startWithSpace) ->
+      # escape RegExp
+      flag = flag.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&")
+
+      # À
+      _a = decodeURI("%C3%80")
+      # ÿ
+      _y = decodeURI("%C3%BF")
+      regexp = new RegExp "(?:\\B|\\W|\\s)#{flag}([A-Za-z#{_a}-#{_y}0-9_\'\.\+\-]*)|([^\\x00-\\xff]*)$", 'gi'
+      match = regexp.exec subtext
+      if match then match[2] || match[1] else null
 
   # Add GFM auto-completion to all input fields, that accept GFM input.
   setup: (wrap) ->
@@ -89,6 +100,7 @@ GitLab.GfmAutoComplete =
         sorter: @DefaultOptions.sorter
         filter: @DefaultOptions.filter
         beforeInsert: @DefaultOptions.beforeInsert
+        matcher: @DefaultOptions.matcher
 
     # Team Members
     @input.atwho
@@ -106,6 +118,7 @@ GitLab.GfmAutoComplete =
         sorter: @DefaultOptions.sorter
         filter: @DefaultOptions.filter
         beforeInsert: @DefaultOptions.beforeInsert
+        matcher: @DefaultOptions.matcher
         beforeSave: (members) ->
           $.map members, (m) ->
             return m if not m.username?
@@ -133,6 +146,7 @@ GitLab.GfmAutoComplete =
         sorter: @DefaultOptions.sorter
         filter: @DefaultOptions.filter
         beforeInsert: @DefaultOptions.beforeInsert
+        matcher: @DefaultOptions.matcher
         beforeSave: (issues) ->
           $.map issues, (i) ->
             return i if not i.title?
@@ -154,6 +168,7 @@ GitLab.GfmAutoComplete =
       data: ['loading']
       startWithSpace: false
       callbacks:
+        matcher: @DefaultOptions.matcher
         beforeSave: (milestones) ->
           $.map milestones, (m) ->
             return m if not m.title?
@@ -178,6 +193,7 @@ GitLab.GfmAutoComplete =
         sorter: @DefaultOptions.sorter
         filter: @DefaultOptions.filter
         beforeInsert: @DefaultOptions.beforeInsert
+        matcher: @DefaultOptions.matcher
         beforeSave: (merges) ->
           $.map merges, (m) ->
             return m if not m.title?
@@ -194,6 +210,7 @@ GitLab.GfmAutoComplete =
       insertTpl: '${atwho-at}${title}'
       startWithSpace: false
       callbacks:
+        matcher: @DefaultOptions.matcher
         beforeSave: (merges) ->
           sanitizeLabelTitle = (title)->
             if /[\w\?&]+\s+[\w\?&]+/g.test(title)

spec/features/issues/gfm_autocomplete_spec.rb

@@ -9,16 +9,34 @@ feature 'GFM autocomplete', feature: true, js: true do
     project.team << [user, :master]
     login_as(user)
     visit namespace_project_issue_path(project.namespace, project, issue)
+
+    sleep 2
   end
 
-  it 'opens autocomplete menu when doesnt starts with space' do
-    sleep 2
-
+  it 'opens autocomplete menu when field starts with text' do
     page.within '.timeline-content-form' do
-      find('#note_note').native.send_keys('testing')
+      find('#note_note').native.send_keys('')
       find('#note_note').native.send_keys('@')
     end
 
     expect(page).to have_selector('.atwho-view')
   end
+
+  it 'opens autocomplete menu when field is prefixed with non-text character' do
+    page.within '.timeline-content-form' do
+      find('#note_note').native.send_keys('')
+      find('#note_note').native.send_keys('@')
+    end
+
+    expect(page).to have_selector('.atwho-view')
+  end
+
+  it 'doesnt open autocomplete menu character is prefixed with text' do
+    page.within '.timeline-content-form' do
+      find('#note_note').native.send_keys('testing')
+      find('#note_note').native.send_keys('@')
+    end
+
+    expect(page).not_to have_selector('.atwho-view')
+  end
 end