From bf697f344a55a7adbf5d4f9a201dba4669e339af Mon Sep 17 00:00:00 2001
From: Raymond Hill <rhill@raymondhill.net>
Date: Mon, 30 Sep 2019 18:21:24 -0400
Subject: [PATCH] Log procedural cosmetic exception filters

Related issue:
- https://github.com/gorhill/uBlock/issues/127

Procedural cosmetic exception filters were the
last class of cosmetic exception filters not
being reported in the logger; this commit fixes
this.

Additionally, ensure that a single DOM listener
can't prevent other listeners from being
processed by throwing an exception. Such approach
would have prevented regression leading to
emergency release 1.22.4:
- https://github.com/gorhill/uBlock/releases/tag/1.22.4
---
 src/js/contentscript.js              | 11 +++++++----
 src/js/scriptlets/cosmetic-logger.js | 20 +++++++++++++++++---
 2 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/src/js/contentscript.js b/src/js/contentscript.js
index 42b83e25f..7ed08c7d2 100644
--- a/src/js/contentscript.js
+++ b/src/js/contentscript.js
@@ -267,7 +267,7 @@ vAPI.SafeAnimationFrame.prototype = {
 /******************************************************************************/
 /******************************************************************************/
 
-vAPI.domWatcher = (function() {
+vAPI.domWatcher = (( ) => {
 
     const addedNodeLists = [];
     const removedNodeLists = [];
@@ -311,7 +311,8 @@ vAPI.domWatcher = (function() {
         //console.timeEnd('dom watcher/safe observer handler');
         if ( addedNodes.length === 0 && removedNodes === false ) { return; }
         for ( const listener of getListenerIterator() ) {
-            listener.onDOMChanged(addedNodes, removedNodes);
+            try { listener.onDOMChanged(addedNodes, removedNodes); }
+            catch (ex) { }
         }
         addedNodes.length = 0;
         removedNodes = false;
@@ -373,7 +374,8 @@ vAPI.domWatcher = (function() {
         listeners.push(listener);
         listenerIteratorDirty = true;
         if ( domIsReady !== true ) { return; }
-        listener.onDOMCreated();
+        try { listener.onDOMCreated(); }
+        catch (ex) { }
         startMutationObserver();
     };
 
@@ -401,7 +403,8 @@ vAPI.domWatcher = (function() {
     const start = function() {
         domIsReady = true;
         for ( const listener of getListenerIterator() ) {
-            listener.onDOMCreated();
+            try { listener.onDOMCreated(); }
+            catch (ex) { }
         }
         startMutationObserver();
     };
diff --git a/src/js/scriptlets/cosmetic-logger.js b/src/js/scriptlets/cosmetic-logger.js
index 1120c68d4..e8be4fc4a 100644
--- a/src/js/scriptlets/cosmetic-logger.js
+++ b/src/js/scriptlets/cosmetic-logger.js
@@ -46,6 +46,7 @@ let declarativeStyleStr;
 const proceduralDict = new Map();
 const exceptionDict = new Map();
 let exceptionStr;
+const proceduralExceptionDict = new Map();
 const nodesToProcess = new Set();
 const loggedSelectors = new Set();
 
@@ -172,6 +173,17 @@ const processExceptions = function(out) {
 
 /******************************************************************************/
 
+const processProceduralExceptions = function(out) {
+    if ( proceduralExceptionDict.size === 0 ) { return; }
+    for ( const exception of proceduralExceptionDict.values() ) {
+        if ( exception.test() === false ) { continue; }
+        out.push(`#@#${exception.raw}`);
+        proceduralExceptionDict.delete(exception.raw);
+    }
+};
+
+/******************************************************************************/
+
 const processTimer = new vAPI.SafeAnimationFrame(( ) => {
     //console.time('dom logger/scanning for matches');
     processTimer.clear();
@@ -193,6 +205,7 @@ const processTimer = new vAPI.SafeAnimationFrame(( ) => {
     processDeclarativeStyle(toLog);
     processProcedural(toLog);
     processExceptions(toLog);
+    processProceduralExceptions(toLog);
 
     nodesToProcess.clear();
 
@@ -268,9 +281,10 @@ const handlers = {
                     exceptionDict.set(details.style[0], details.raw);
                     continue;
                 }
-                // TODO:
-                // Handling of procedural cosmetic exception filters
-                // not implemented.
+                proceduralExceptionDict.set(
+                    details.raw,
+                    vAPI.domFilterer.createProceduralFilter(details)
+                );
             }
             exceptionStr = undefined;
         }