From 1c4347d69d540916b609835dd63c56a11ab7b2e5 Mon Sep 17 00:00:00 2001
From: gorhill <rhill@raymondhill.net>
Date: Mon, 13 Feb 2017 08:33:10 -0500
Subject: [PATCH] element picker improvement: to not discard class information
 when an id is available

Use class(es) whenever available instead of the id when selecting a
broad cosmetic filter (ctrl-click).
When asking for a broad cosmetic filter, using the id instead of
whatever available class(es) is limiting usefulness. The change
here address this.
Example of use case: open
<http://forums.mozillazine.org/viewtopic.php?f=38&t=3027325>.
Now how to remove all signature widgets from all posts?
Without the change here, this was not possible without opening the
browser's inspector, finding out and manually typing whatever class
is used to identify the signature's root element.
With this commit, ctrl-click will now use whatever class information
exist instead of the id.
---
 src/js/scriptlets/element-picker.js | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/src/js/scriptlets/element-picker.js b/src/js/scriptlets/element-picker.js
index 80d0b4aa4..1ab7e12d7 100644
--- a/src/js/scriptlets/element-picker.js
+++ b/src/js/scriptlets/element-picker.js
@@ -489,13 +489,11 @@ var cosmeticFilterFromElement = function(elem) {
     }
 
     // Class(es)
-    if ( selector === '' ) {
-        v = elem.classList;
-        if ( v ) {
-            i = v.length || 0;
-            while ( i-- ) {
-                selector += '.' + CSS.escape(v.item(i));
-            }
+    v = elem.classList;
+    if ( v ) {
+        i = v.length || 0;
+        while ( i-- ) {
+            selector += '.' + CSS.escape(v.item(i));
         }
     }
 
@@ -1036,13 +1034,22 @@ var candidateFromFilterChoice = function(filterChoice) {
     // - Do not compute exact path.
     // - Discard narrowing directives.
     if ( filterChoice.modifier ) {
-        return filter.replace(/:nth-of-type\(\d+\)/, '');
+        filter = filter.replace(/:nth-of-type\(\d+\)/, '');
+        // Remove the id if one or more classes exist.
+        if ( filter.charAt(2) === '#' && filter.indexOf('.') !== -1 ) {
+            filter = filter.replace(/#[^#.]+/, '');
+        }
+        return filter;
     }
 
     // Return path: the target element, then all siblings prepended
     var selector = '', joiner = '';
     for ( ; slot < filters.length; slot++ ) {
         filter = filters[slot];
+        // Remove all classes when an id exists.
+        if ( filter.charAt(2) === '#' ) {
+            filter = filter.replace(/\..+$/, '');
+        }
         selector = filter.slice(2) + joiner + selector;
         // Stop at any element with an id: these are unique in a web page
         if ( filter.lastIndexOf('###', 0) === 0 ) {