Reduce local variables usage in CoffeeScript

Local variables are one of the things CoffeeScript doesn't compile to
modern JavaScript automatically: it uses `var` instead of `const` or
`let`.

Besides, using `$this = $(this)` is usually done to reference the
current object in another function where the current object is a
different one. Here we were using it with no clear purpose.

app/assets/javascripts/checkbox_toggle.js.coffee

@@ -4,9 +4,8 @@ App.CheckboxToggle =
 
   initialize: ->
     $("[data-checkbox-toggle]").on "change", ->
-      $this = $(this)
-      $target = $($this.data("checkbox-toggle"))
-      if $this.is(":checked")
+      $target = $($(this).data("checkbox-toggle"))
+      if $(this).is(":checked")
         $target.show()
       else
         $target.hide()

app/assets/javascripts/columns_selector.js.coffee

@@ -41,12 +41,10 @@ App.ColumnsSelector =
     $(".column-selector-item input").prop("checked", false)
 
   toggleColumn: (event) ->
-    column = $(event.target).data("column")
-    App.ColumnsSelector.displayColumn(column)
+    App.ColumnsSelector.displayColumn($(event.target).data("column"))
 
   displayColumn: (column) ->
-    item = $("#column_selector_" + column)
-    if item.prop("checked")
+    if $("#column_selector_" + column).prop("checked")
       $("[data-field=" + column + "]").removeClass("hidden")
     else
       $("[data-field=" + column + "]").addClass("hidden")

app/assets/javascripts/comments.js.coffee

@@ -42,12 +42,9 @@ App.Comments =
 
   initialize: ->
     $("body .js-add-comment-link").each ->
-      $this = $(this)
-
-      unless $this.data("initialized") is "yes"
-        $this.on("click", ->
-          id = $(this).data().id
-          App.Comments.toggle_form(id)
+      unless $(this).data("initialized") is "yes"
+        $(this).on("click", ->
+          App.Comments.toggle_form($(this).data().id)
           false
         ).data "initialized", "yes"
 

app/assets/javascripts/documentable.js.coffee

@@ -3,9 +3,7 @@
 App.Documentable =
 
   initialize: ->
-
-    inputFiles = $(".js-document-attachment")
-    inputFiles.each ->
+    $(".js-document-attachment").each ->
       App.Documentable.initializeDirectUploadInput(this)
 
     $("#nested-documents").on "cocoon:after-remove", ->

app/assets/javascripts/forms.js.coffee

@@ -27,9 +27,7 @@ App.Forms =
 
   synchronizeInputs: ->
     progress_bar = "[name='progress_bar[percentage]']"
-    process_background = "[name='legislation_process[background_color]']"
-    process_font = ", [name='legislation_process[font_color]']"
-    processes = process_background + process_font
+    processes = "[name='legislation_process[background_color]'], [name='legislation_process[font_color]']"
     banners = "[name='banner[background_color]'], [name='banner[font_color]']"
 
     inputs = $("#{progress_bar}, #{processes}, #{banners}")

app/assets/javascripts/globalize.js.coffee

@@ -89,14 +89,12 @@ App.Globalize =
       App.Globalize.update_description()
 
     $(".js-select-language").on "change", ->
-      locale = $(this).val()
-      App.Globalize.display_translations(locale)
+      App.Globalize.display_translations($(this).val())
 
     $(".js-delete-language").on "click", (e) ->
       e.preventDefault()
-      locale = $(this).data("locale")
+      App.Globalize.remove_language($(this).data("locale"))
       $(this).hide()
-      App.Globalize.remove_language(locale)
 
     $(".js-add-fields-container").on "cocoon:after-insert", ->
       App.Globalize.enabled_locales().forEach (locale) ->

app/assets/javascripts/imageable.js.coffee

@@ -3,8 +3,7 @@
 App.Imageable =
 
   initialize: ->
-    inputFiles = $(".js-image-attachment")
-    inputFiles.each ->
+    $(".js-image-attachment").each ->
       App.Imageable.initializeDirectUploadInput(this)
 
     $("#nested-image").on "cocoon:after-remove", ->

app/assets/javascripts/legislation_annotatable.js.coffee

@@ -20,7 +20,7 @@ App.LegislationAnnotatable =
     try
       if !document.execCommand("BackColor", false, colour)
         App.LegislationAnnotatable.makeEditableAndHighlight colour
-    catch ex
+    catch
       App.LegislationAnnotatable.makeEditableAndHighlight colour
 
     return
@@ -182,9 +182,8 @@ App.LegislationAnnotatable =
     current_user_id = $("html").data("current-user-id")
 
     $(".legislation-annotatable").each ->
-      $this          = $(this)
-      ann_id         = $this.data("legislation-draft-version-id")
-      base_url       = $this.data("legislation-annotatable-base-url")
+      ann_id   = $(this).data("legislation-draft-version-id")
+      base_url = $(this).data("legislation-annotatable-base-url")
 
       App.LegislationAnnotatable.app = new annotator.App()
         .include ->
@@ -203,7 +202,4 @@ App.LegislationAnnotatable =
 
       App.LegislationAnnotatable.app.start().then ->
         App.LegislationAnnotatable.app.ident.identity = current_user_id
-
-        options = {}
-        options["legislation_draft_version_id"] = ann_id
-        App.LegislationAnnotatable.app.annotations.load(options)
+        App.LegislationAnnotatable.app.annotations.load(legislation_draft_version_id: ann_id)

app/assets/javascripts/managers.js.coffee

@@ -16,8 +16,7 @@ App.Managers =
 
   initialize: ->
     $(".generate-random-value").on "click", ->
-      password = App.Managers.generatePassword()
-      $("#user_password").val(password)
+      $("#user_password").val(App.Managers.generatePassword())
 
     $(".show-password").on "click", ->
       if $("#user_password").is("input[type='password']")

app/assets/javascripts/map.js.coffee

@@ -3,9 +3,7 @@
 App.Map =
 
   initialize: ->
-    maps = $("*[data-map]")
-
-    maps.each ->
+    $("*[data-map]").each ->
       App.Map.initializeMap(this)
 
     $(".js-toggle-map").on
@@ -83,8 +81,7 @@ App.Map =
           e.target.bindPopup(getPopupContent(data)).openPopup()
 
     getPopupContent = (data) ->
-      content = "<a href='/budgets/#{data["budget_id"]}/investments/#{data["investment_id"]}'>#{data["investment_title"]}</a>"
-      return content
+      "<a href='/budgets/#{data["budget_id"]}/investments/#{data["investment_id"]}'>#{data["investment_title"]}</a>"
 
     mapCenterLatLng  = new (L.LatLng)(mapCenterLatitude, mapCenterLongitude)
     map              = L.map(element.id).setView(mapCenterLatLng, zoom)

app/assets/javascripts/markdown_editor.js.coffee

@@ -34,8 +34,8 @@ App.MarkdownEditor =
         editor.toggleClass("fullscreen")
         $(".fullscreen-container").toggleClass("medium-8", "medium-12")
         span = $(this).find("span")
-        current_html = span.html()
-        if(current_html == span.data("open-text"))
+
+        if(span.html() == span.data("open-text"))
           span.html(span.data("closed-text"))
         else
           span.html(span.data("open-text"))

app/assets/javascripts/polls.js.coffee

@@ -18,8 +18,7 @@ App.Polls =
     App.Polls.replaceToken(token)
 
     $(".zoom-link").on "click", (event) ->
-      element = event.target
-      answer = $(element).closest("div.answer")
+      answer = $(event.target).closest("div.answer")
 
       if $(answer).hasClass("medium-6")
         $(answer).removeClass("medium-6")

app/assets/javascripts/social_share.js.coffee

@@ -4,6 +4,4 @@ App.SocialShare =
 
   initialize: ->
     $(".social-share-button a").each ->
-      element = $(this)
-      site = element.data("site")
-      element.append("<span class='show-for-sr'>#{site}</span>")
+      $(this).append("<span class='show-for-sr'>#{$(this).data("site")}</span>")

app/assets/javascripts/tags.js.coffee

@@ -6,10 +6,8 @@ App.Tags =
     $tag_input = $("input.js-tag-list")
 
     $("body .js-add-tag-link").each ->
-      $this = $(this)
-
-      unless $this.data("initialized") is "yes"
-        $this.on("click", ->
+      unless $(this).data("initialized") is "yes"
+        $(this).on("click", ->
           name = "\"#{$(this).text()}\""
           current_tags = $tag_input.val().split(",").filter(Boolean)
 

app/assets/javascripts/tree_navigator.js.coffee

@@ -2,9 +2,7 @@
 
 App.TreeNavigator =
   setNodes: (nodes) ->
-    children = nodes.children("ul")
-
-    children.each ->
+    nodes.children("ul").each ->
       link = $(this).prev("a")
       $('<span class="open"></span>').insertBefore(link)
       App.TreeNavigator.setNodes($(this).children())
@@ -20,13 +18,12 @@ App.TreeNavigator =
 
     $("[data-tree-navigator] span").on
       click: ->
-        elem = $(this)
-        if(elem.hasClass("open"))
-          elem.removeClass("open").addClass("closed")
-          elem.siblings("ul").hide()
-        else if(elem.hasClass("closed"))
-          elem.removeClass("closed").addClass("open")
-          elem.siblings("ul").show()
+        if($(this).hasClass("open"))
+          $(this).removeClass("open").addClass("closed")
+          $(this).siblings("ul").hide()
+        else if($(this).hasClass("closed"))
+          $(this).removeClass("closed").addClass("open")
+          $(this).siblings("ul").show()
 
     anchor = $(location).attr("hash")
 

app/assets/javascripts/watch_form_changes.js.coffee

@@ -24,5 +24,4 @@ App.WatchFormChanges =
     $(document).off("page:before-change").on("page:before-change", App.WatchFormChanges.checkChanges)
 
     App.WatchFormChanges.forms().each ->
-      form = $(this)
-      form.data("watchChanges", form.serialize())
+      $(this).data("watchChanges", $(this).serialize())