attach the utitlity function to the global scope with some changes

app/assets/javascripts/issues.js.coffee

@@ -33,12 +33,12 @@
     paramKeys = ['author_id', 'label_name', 'milestone_title', 'assignee_id', 'issue_search']
 
     for paramKey in paramKeys
-      newParams[paramKey] = getUrlParameter(paramKey) or ''
+      newParams[paramKey] = gl.utils.getUrlParameter(paramKey) or ''
 
     if stateFilters.length
       stateFilters.find('a').each ->
         initialUrl = $(this).attr 'href'
-        $(this).attr 'href', mergeUrlParams(newParams, initialUrl)
+        $(this).attr 'href', gl.utils.mergeUrlParams(newParams, initialUrl)
 
   # Make sure we trigger ajax request only after user stop typing
   initSearch: ->

app/assets/javascripts/lib/url_utility.js

-function getUrlParameter(sParam) {
-  var sPageURL = decodeURIComponent(window.location.search.substring(1)),
-      sURLVariables = sPageURL.split('&'),
-      sParameterName,
-      i;
-
-  for (i = 0; i < sURLVariables.length; i++) {
-    sParameterName = sURLVariables[i].split('=');
-
-    if (sParameterName[0] === sParam) {
-      return sParameterName[1] === undefined ? true : sParameterName[1];
-    }
-  }
-}
-
-/**
- * @param {Object} params - url keys and value to merge
- * @param {String} url
- */
-function mergeUrlParams(params, url){
-  var newUrl = decodeURIComponent(url);
-
-  Object.keys(params).forEach(function(paramName) {
-    var pattern = new RegExp('\\b('+paramName+'=).*?(&|$)')
-    if (url.search(pattern) >= 0){
-      newUrl = newUrl.replace(pattern,'$1' + params[paramName] + '$2');
-    } else {
-      newUrl = newUrl + (newUrl.indexOf('?') > 0 ? '&' : '?') + paramName + '=' + params[paramName]
-    }
-  });
-
-  return newUrl;
-}
\ No newline at end of file

app/assets/javascripts/lib/url_utility.js.coffee

+((w) ->
+
+  w.gl ?= {}
+  w.gl.utils ?= {}
+
+  w.gl.utils.getUrlParameter = (sParam) ->
+    sPageURL = decodeURIComponent(window.location.search.substring(1))
+    sURLVariables = sPageURL.split('&')
+    sParameterName = undefined
+    i = 0
+    while i < sURLVariables.length
+      sParameterName = sURLVariables[i].split('=')
+      if sParameterName[0] is sParam
+        return if sParameterName[1] is undefined then true else sParameterName[1]
+      i++
+
+  # #
+  #  @param {Object} params - url keys and value to merge
+  #  @param {String} url
+  # #
+  w.gl.utils.mergeUrlParams = (params, url) ->
+    newUrl = decodeURIComponent(url)
+    for paramName, paramValue of params
+      pattern = new RegExp "\\b(#{paramName}=).*?(&|$)"
+      if url.search(pattern) >= 0
+        newUrl = newUrl.replace pattern, "$1#{paramValue}$2"
+      else
+        newUrl = "#{newUrl}#{(if newUrl.indexOf('?') > 0 then '&' else '?')}#{paramName}=#{paramValue}"
+    newUrl
+
+) window