fontlist: Skip fonts with missing family_name (#6820)

* Also don't trip on pipes

frontend/fontlist.lua

@@ -117,15 +117,17 @@ local function collectFaceInfo(path)
             return nil
         end
 
-        local fres = face:getInfo()
-        local hbface = HB.hb_ft_face_create_referenced(face)
-        fres.names = hbface:getNames()
-        fres.scripts, fres.langs = hbface:getCoverage()
-        fres.path = path
-        fres.index = i
-        table.insert(res, fres)
-
-        hbface:destroy()
+        -- If family_name is missing, it's probably too broken to be useful
+        if face.family_name ~= nil then
+            local fres = face:getInfo()
+            local hbface = HB.hb_ft_face_create_referenced(face)
+            fres.names = hbface:getNames()
+            fres.scripts, fres.langs = hbface:getCoverage()
+            fres.path = path
+            fres.index = i
+            table.insert(res, fres)
+            hbface:destroy()
+        end
         face:done()
     end
     return res

frontend/util.lua

@@ -594,7 +594,7 @@ function util.findFiles(dir, cb)
                 if f ~= "." and f ~= ".." then
                     scan(path)
                 end
-            else
+            elseif attr.mode == "file" or attr.mode == "link" then
                 cb(path, f, attr)
             end
         end