feat: to network modifier

packages/adblocker/src/filters/network.ts

@@ -725,14 +725,23 @@ export default class NetworkFilter implements IFilter {
       // --------------------------------------------------------------------- //
       // parseOptions
       // --------------------------------------------------------------------- //
+      const denyallowEntities: Set<string> = new Set();
       for (const rawOption of getFilterOptions(line, optionsIndex + 1, line.length)) {
         const negation = rawOption[0].charCodeAt(0) === 126; /* '~' */
         const option = negation === true ? rawOption[0].slice(1) : rawOption[0];
         const value = rawOption[1];
 
         switch (option) {
+          case 'to':
           case 'denyallow': {
-            denyallow = Domains.parse(value.split('|'), debug);
+            let parts = value.split('|');
+            if (option === 'to') {
+              parts = parts.map((part) =>
+                part.charCodeAt(0) === 126 /* '~' */ ? part.slice(1) : `~${part}`,
+              );
+            }
+            parts.forEach((part) => denyallowEntities.add(part));
+            denyallow = Domains.parse(Array.from(denyallowEntities), debug);
             break;
           }
           case 'domain':
@@ -1525,7 +1534,7 @@ export default class NetworkFilter implements IFilter {
 
     if (this.denyallow !== undefined) {
       if (this.denyallow.parts !== undefined) {
-        options.push(`denyallow=${this.denyallow.parts}`);
+        options.push(`denyallow=${this.denyallow.parts.replace(/,/g, '|')}`);
       } else {
         options.push('denyallow=<hashed>');
       }

packages/adblocker/test/matching.test.ts

@@ -396,6 +396,23 @@ describe('#NetworkFilter.match', () => {
       url: 'https://sub.y.com/bar',
       type: 'script',
     });
+
+    // to
+    expect(f`*$3p,from=a.com,to=b.com`).to.matchRequest({
+      sourceUrl: 'https://a.com',
+      url: 'https://b.com/bar',
+      type: 'script',
+    });
+    expect(f`*$frame,3p,from=a.com|b.com,to=~c.com`).to.not.matchRequest({
+      sourceUrl: 'https://a.com',
+      url: 'https://c.com/bar',
+      type: 'sub_frame',
+    });
+    expect(f`$frame,csp=non-relevant,to=~safe.com,from=c.com|d.com`).to.not.matchRequest({
+      sourceUrl: 'https://c.com',
+      url: 'https://safe.com/foo',
+      type: 'sub_frame',
+    });
   });
 });
 

packages/adblocker/test/parsing.test.ts

@@ -803,6 +803,29 @@ describe('Network filters', () => {
           denyallow: undefined,
         });
       });
+
+      context('to', () => {
+        it('reverses domains condition', () => {
+          network('||foo.com$to=foo.com|~bar.com,denyallow=bar.com|~foo.com', {
+            denyallow: {
+              hostnames: h(['bar.com']),
+              entities: undefined,
+              notHostnames: h(['foo.com']),
+              notEntities: undefined,
+              parts: undefined,
+            },
+          });
+          network('||foo.com$to=bar.com|baz.com', {
+            denyallow: {
+              hostnames: undefined,
+              entities: undefined,
+              notHostnames: h(['bar.com', 'baz.com']),
+              notEntities: undefined,
+              parts: undefined,
+            },
+          });
+        });
+      });
     });
 
     describe('redirect', () => {