Issue 3176 - Keep filter list parameters

abp2blocklist.js

Index: abp2blocklist.js
===================================================================
--- a/abp2blocklist.js
+++ b/abp2blocklist.js
@@ -5,6 +5,7 @@
 
 var typeMap = filterClasses.RegExpFilter.typeMap;
 
+var params = {};
 var requestFilters = [];
 var requestExceptions = [];
 var elemhideFilters = [];
@@ -69,6 +70,18 @@
 		recordSelectorException(filter);
 }
 
+function parseLine(line) {
+	var paramMatch = /^\s*!\s*([\w ]+)\s*:\s*(.*)/.exec(line);

[Sebastian Noack, 2015/10/13 11:25:08]

I think we should leave the parsing to the core code imported from ABP. So
instead using a regex here you could check for CommentFilter objects returned by
Filter.fromText().

+	if (paramMatch) {
+		var key = paramMatch[1];
+		var paramsToKeep = ["version", "title", "last modified", "expires", "homepage", "licence"];
+		if (paramsToKeep.indexOf(key.toLowerCase()) != -1)
+			params[key] = paramMatch[2];
+		return;
+	}
+	parseFilter(line);
+}
+
 function escapeRegExp(s) {
 	return s.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
 }
@@ -265,9 +278,12 @@
 	for (i = 0; i < requestExceptions.length; i++)
 		addRule(convertFilter(requestExceptions[i], "ignore-previous-rules", true));
 
+	for (key in params)
+		if (params.hasOwnProperty(key))
+			console.log("// " + key + ": " + params[key]);

[Sebastian Noack, 2015/10/13 11:25:08]

But anyway, valid JSON cannot have comments. So NOT LGTM.

[Felix Dahlke, 2015/10/13 11:37:26]

Did you read https://issues.adblockplus.org/ticket/3176?

The only alternative I see so far is to return a different JSON structure, i.e.
not an array of content blocking rule objects. Stripping out comments is easy,
stripping out anything else on the client-side is more involved.

[Felix Dahlke, 2015/10/13 11:52:15]

But well, different approaches shouldn't be discussed here, that should go into
https://issues.adblockplus.org/ticket/3176. Please have a look and suggest a
different approach there.

 	console.log(JSON.stringify(rules, null, "\t"));
 }
 
 var rl = readline.createInterface({input: process.stdin, terminal: false});
-rl.on("line", parseFilter);
+rl.on("line", parseLine);
 rl.on("close", logRules);