filter test dialog improvements:

- properly return results for filter rules matching specific feeds or
   categories
 - fix test results never returned for Uncategorized
 - show tooltip with specific word match and matched rule on resulting
   item hover

js/CommonFilters.js

@@ -19,6 +19,9 @@ const	Filters = {
 			ACTION_REMOVE_TAG: 10,
 			PARAM_ACTIONS: [4, 6, 7, 9, 10],
 			filter_info: {},
+			formatMatchedRules: function(rules) {
+				return rules.map((r) => r.regexp_matches[0] + ' - ' + r.reg_exp).join('\n');
+			},
 			test: function() {
 				const test_dialog = new fox.SingleUseDialog({
 					title: "Test Filter",
@@ -43,8 +46,8 @@ const	Filters = {
 												.replace("%f", test_dialog.results)
 												.replace("%d", offset);
 
-										results_list.innerHTML += result.items.reduce((current, item) => current + `<li><span class='title'>${item.title}</span><br>
-												<span class='feed'>${item.feed_title}</span>, <span class='date'>${item.date}</span>
+										results_list.innerHTML += result.items.reduce((current, item) => current + `<li title="${App.escapeHtml(dialog.formatMatchedRules(item.matched_rules))}"><span class='title'>${item.title}</span>
+												&mdash; <span class='feed'>${item.feed_title}</span>, <span class='date'>${item.date}</span>
 												<div class='preview text-muted'>${item.content_preview}</div></li>`, '');
 
 										// get the next batch if there may be more available and testing limits haven't been reached