ensure element list is unique

Author: alexcjohnson

scripts/data/elements.txt

@@ -1,49 +1,94 @@
-link
-meta
-title
+a
+abbr
+acronym
 address
+area
 article
 aside
+audio
+b
+base
+basefont
+bdi
+bdo
+big
+blink
+blockquote
+br
+button
+canvas
+caption
+center
+cite
+code
+col
+colgroup
+command
+content
+data
+datalist
+dd
+del
+details
+dfn
+dialog
+div
+dl
+dt
+element
+em
+embed
+fieldset
+figcaption
+figure
+font
 footer
-header
+form
+frame
+frameset
 h1
 h2
 h3
 h4
 h5
 h6
+header
 hgroup
-main
-nav
-section
-blockquote
-dd
-div
-dl
-dt
-figcaption
-figure
 hr
+i
+iframe
+img
+ins
+isindex
+kbd
+keygen
+label
+legend
 li
+link
+listing
 main
+map
+mark
+marquee
+meta
+meter
+multicol
+nav
+nextid
+nobr
+noscript
+object
 ol
+optgroup
+option
+output
 p
+param
+picture
+plaintext
 pre
-ul
-a
-abbr
-b
-bdi
-bdo
-br
-cite
-code
-data
-dfn
-em
-i
-kbd
-mark
+progress
 q
 rb
 rp
@@ -52,92 +97,35 @@ rtc
 ruby
 s
 samp
+script
+section
+select
+shadow
+slot
 small
+source
+spacer
 span
+strike
 strong
 sub
+summary
 sup
-time
-u
-var
-wbr
-area
-audio
-img
-map
-track
-video
-embed
-iframe
-object
-param
-picture
-source
-canvas
-noscript
-script
-del
-ins
-caption
-col
-colgroup
 table
 tbody
 td
+template
+textarea
 tfoot
 th
 thead
+time
+title
 tr
-button
-datalist
-fieldset
-form
-label
-legend
-meter
-optgroup
-option
-output
-progress
-select
-textarea
-details
-dialog
-summary
-content
-element
-shadow
-slot
-template
-acronym
-basefont
-big
-blink
-center
-command
-content
-element
-font
-frame
-frameset
-isindex
-keygen
-listing
-marquee
-multicol
-nextid
-nobr
-plaintext
-shadow
-spacer
-strike
-xmp
-base
-section
-h1
-h2
-h3
-h4
-h5
-h6
-iframe
+track
+u
+ul
+var
+video
+wbr
+xmp

scripts/extract-elements.js

@@ -40,7 +40,14 @@ function extractElements($) {
             return list.concat(subList);
         }, [])
         .filter(element => excludeElements.indexOf(element) === -1)
-        .concat(addElements);
+        .concat(addElements)
+        .sort()
+        .reduce((list, element) => {
+            if(!list.length || element !== list[list.length - 1]) {
+                list.push(element);
+            }
+            return list;
+        }, []);
 }
 
 request(refUrl, (error, response, html) => {