Issue 3673 - Merge closely matching rules

test/abp2blocklist.js

Index: test/abp2blocklist.js
===================================================================
--- a/test/abp2blocklist.js
+++ b/test/abp2blocklist.js
@@ -15,350 +15,493 @@
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 "use strict";
 
 let Filter = require("filterClasses").Filter;
 let ContentBlockerList = require("../lib/abp2blocklist.js").ContentBlockerList;
 
-function testRules(test, filters, expected, transformFunction)
+function runTest(test, assertions)
 {
-  let blockerList = new ContentBlockerList();
+  // All the assertions are run in parallel but we wait for all of them to
+  // finish before moving on to the next test.
+  test.expect(assertions.length);
+  Promise.all(assertions).then(() => test.done());
+}
+
+function testRules(test, filters, expected, transformFunction, options)
+{
+  let blockerList = new ContentBlockerList(options);
   for (let filter of filters)
     blockerList.addFilter(Filter.fromText(filter));
 
-  let rules = blockerList.generateRules();
-  if (transformFunction)
-    rules = transformFunction(rules);
+  return blockerList.generateRules().then(rules =>
+  {
+    if (transformFunction)
+      rules = transformFunction(rules);
 
-  test.deepEqual(rules, expected);
+    test.deepEqual(rules, expected);
+  });
 }
 
 exports.generateRules = {
   testElementHiding: function(test)
   {
-    testRules(test, ["##.whatever"], [
-      {trigger: {"url-filter": "^https?://",
-                 "url-filter-is-case-sensitive": true},
-       action: {type: "css-display-none", selector: ".whatever"}}
+    runTest(test, [
+      testRules(test, ["##.whatever"], [
+        {trigger: {"url-filter": "^https?://",
+                   "url-filter-is-case-sensitive": true},
+         action: {type: "css-display-none", selector: ".whatever"}}
+      ]),
+      testRules(test, ["test.com##.whatever"], [
+        {trigger: {"url-filter": "^https?://([^/:]*\\.)?test\\.com[/:]",
+                   "url-filter-is-case-sensitive": true},
+         action: {type: "css-display-none", selector: ".whatever"}}
+      ])
     ]);
-    testRules(test, ["test.com##.whatever"], [
-      {trigger: {"url-filter": "^https?://([^/:]*\\.)?test\\.com[/:]",
-                 "url-filter-is-case-sensitive": true},
-       action: {type: "css-display-none", selector: ".whatever"}}
-    ]);
-
-    test.done();
   },
 
   testElementHidingExceptions: function(test)
   {
-    testRules(test, [
-      "##.whatever",
-      "test.com,anothertest.com###something",
-      "@@||special.test.com^$elemhide",
-      "@@||test.com^$generichide",
-      "@@||anothertest.com^$elemhide",
-      "@@^something^$elemhide",
-      "@@^anything^$generichide"
-    ], [
-      ["^https?://", ["*test.com", "*special.test.com", "*anothertest.com"]],
-      ["^https?://([^/:]*\\.)?test\\.com[/:]", ["*special.test.com"]]
-    ], rules => rules.map(rule => [rule.trigger["url-filter"],
-                                   rule.trigger["unless-domain"]]));
+    runTest(test, [
+      testRules(test, [
+        "##.whatever",
+        "test.com,anothertest.com###something",
+        "@@||special.test.com^$elemhide",
+        "@@||test.com^$generichide",
+        "@@||anothertest.com^$elemhide",
+        "@@^something^$elemhide",
+        "@@^anything^$generichide"
+      ], [
+        ["^https?://", ["*test.com", "*special.test.com", "*anothertest.com"]],
+        ["^https?://([^/:]*\\.)?test\\.com[/:]", ["*special.test.com"]]
+      ], rules => rules.map(rule => [rule.trigger["url-filter"],
+                                     rule.trigger["unless-domain"]])),
 
-    testRules(test, ["#@#whatever"], []);
-    testRules(test, ["test.com#@#whatever"], []);
-    testRules(test, ["~test.com#@#whatever"], []);
+      testRules(test, ["#@#whatever"], []),
+      testRules(test, ["test.com#@#whatever"], []),
+      testRules(test, ["~test.com#@#whatever"], []),
 
-    // We currently completely ignore any element hiding filters that have the
-    // same selector as an element hiding exception. In these examples #whatever
-    // should be hidden for all domains not ending in test.com instead of
-    // nowhere!
-    testRules(test, ["test.com#@#whatever", "##whatever"], []);
-    testRules(test, ["~test.com##whatever"], []);
-
-    test.done();
+      // We currently completely ignore any element hiding filters that have the
+      // same selector as an element hiding exception. In these examples
+      // #whatever should be hidden for all domains not ending in test.com
+      // instead of nowhere!
+      testRules(test, ["test.com#@#whatever", "##whatever"], []),
+      testRules(test, ["~test.com##whatever"], [])
+    ]);
   },
 
   testRequestFilters: function(test)
   {
-    testRules(test, [
-      "/foo", "||test.com^", "http://example.com/foo", "^foo^"
-    ], [
-      {
-        trigger: {
-          "url-filter": "^[^:]+:(//)?.*/foo",
-          "resource-type": ["image", "style-sheet", "script", "font",
-                            "media", "raw"]
+    runTest(test, [
+      testRules(test, [
+        "/foo", "||test.com^", "http://example.com/foo", "^foo^"
+      ], [
+        {
+          trigger: {
+            "url-filter": "^[^:]+:(//)?.*/foo",
+            "resource-type": ["image", "style-sheet", "script", "font",
+                              "media", "raw"]
+          },
+          action: {type: "block"}
         },
-        action: {type: "block"}
-      },
-      {
-        trigger: {
-          "url-filter": "^[^:]+:(//)?([^/]+\\.)?test\\.com([^-_.%a-z0-9].*)?$",
-          "url-filter-is-case-sensitive": true,
-          "resource-type": ["image", "style-sheet", "script", "font",
-                            "media", "raw", "document"],
-          "unless-top-url": [
-            "^[^:]+:(//)?([^/]+\\.)?test\\.com([^-_.%a-z0-9].*)?$"
-          ],
-          "top-url-filter-is-case-sensitive": true
+        {
+          trigger: {
+            "url-filter":
+              "^[^:]+:(//)?([^/]+\\.)?test\\.com([^-_.%a-z0-9].*)?$",
+            "url-filter-is-case-sensitive": true,
+            "resource-type": ["image", "style-sheet", "script", "font",
+                              "media", "raw", "document"],
+            "unless-top-url": [
+              "^[^:]+:(//)?([^/]+\\.)?test\\.com([^-_.%a-z0-9].*)?$"
+            ],
+            "top-url-filter-is-case-sensitive": true
+          },
+          action: {type: "block"}
         },
-        action: {type: "block"}
-      },
-      {
-        trigger: {
-          "url-filter": "^http://example\\.com/foo",
-          "resource-type": ["image", "style-sheet", "script", "font",
-                            "media", "raw", "document"],
-          "unless-top-url": ["^http://example\\.com/foo"]
+        {
+          trigger: {
+            "url-filter": "^http://example\\.com/foo",
+            "resource-type": ["image", "style-sheet", "script", "font",
+                              "media", "raw", "document"],
+            "unless-top-url": ["^http://example\\.com/foo"]
+          },
+          action: {type: "block"}
         },
-        action: {type: "block"}
-      },
-      {
-        trigger: {
-          "url-filter": "^[^:]+:(//)?.*http://example\\.com/foo",
-          "resource-type": ["image", "style-sheet", "script", "font",
-                            "media", "raw", "document"],
-          "unless-top-url": ["^[^:]+:(//)?.*http://example\\.com/foo"]
-        },
-        action: {type: "block"}
-      },
-      {
-        trigger: {
-          "url-filter":
-            "^[^:]+:(//)?(.*[^-_.%A-Za-z0-9])?foo([^-_.%A-Za-z0-9].*)?$",
-          "resource-type": ["image", "style-sheet", "script", "font",
-                            "media", "raw"]
+        {
+          trigger: {
+            "url-filter": "^[^:]+:(//)?.*http://example\\.com/foo",
+            "resource-type": ["image", "style-sheet", "script", "font",
+                              "media", "raw", "document"],
+            "unless-top-url": ["^[^:]+:(//)?.*http://example\\.com/foo"]
+          },
+          action: {type: "block"}
         },
-        action: {type: "block"}
-      }
-    ]);
+        {
+          trigger: {
+            "url-filter":
+              "^[^:]+:(//)?(.*[^-_.%A-Za-z0-9])?foo([^-_.%A-Za-z0-9].*)?$",
+            "resource-type": ["image", "style-sheet", "script", "font",
+                              "media", "raw"]
+          },
+          action: {type: "block"}
+        }
+      ]),
 
-    testRules(test, ["||example.com"], [
-      {trigger: {"url-filter": "^[^:]+:(//)?([^/]+\\.)?example\\.com",
-                 "url-filter-is-case-sensitive": true,
-                 "resource-type": ["image", "style-sheet", "script", "font",
-                                   "media", "raw", "document"],
-                 "unless-top-url": ["^[^:]+:(//)?([^/]+\\.)?example\\.com"],
-                 "top-url-filter-is-case-sensitive": true},
+      testRules(test, ["||example.com"], [
+        {trigger: {"url-filter": "^[^:]+:(//)?([^/]+\\.)?example\\.com",
+                   "url-filter-is-case-sensitive": true,
+                   "resource-type": ["image", "style-sheet", "script", "font",
+                                     "media", "raw", "document"],
+                   "unless-top-url": ["^[^:]+:(//)?([^/]+\\.)?example\\.com"],
+                   "top-url-filter-is-case-sensitive": true},
 
-       action: {type: "block"}}
-    ]);
+         action: {type: "block"}}
+      ]),
 
-    // Rules which would match no resource-types shouldn't be generated.
-    testRules(test, ["foo$document", "||foo.com$document"], []);
-
-    test.done();
+      // Rules which would match no resource-types shouldn't be generated.
+      testRules(test, ["foo$document", "||foo.com$document"], [])
+    ]);
   },
 
   testRequestFilterExceptions: function(test)
   {
-    testRules(test, ["@@example.com"], [
-      {trigger: {"url-filter": "^[^:]+:(//)?.*example\\.com",
-                 "resource-type": ["image", "style-sheet", "script", "font",
-                                   "media", "raw", "document"]},
-       action: {type: "ignore-previous-rules"}}
-    ]);
+    runTest(test, [
+      testRules(test, ["@@example.com"], [
+        {trigger: {"url-filter": "^[^:]+:(//)?.*example\\.com",
+                   "resource-type": ["image", "style-sheet", "script", "font",
+                                     "media", "raw", "document"]},
+         action: {type: "ignore-previous-rules"}}
+      ]),
 
-    testRules(test, ["@@||example.com"], [
-      {trigger: {"url-filter": "^[^:]+:(//)?([^/]+\\.)?example\\.com",
-                 "url-filter-is-case-sensitive": true,
-                 "resource-type": ["image", "style-sheet", "script", "font",
-                                   "media", "raw", "document"]},
-       action: {type: "ignore-previous-rules"}}
+      testRules(test, ["@@||example.com"], [
+        {trigger: {"url-filter": "^[^:]+:(//)?([^/]+\\.)?example\\.com",
+                   "url-filter-is-case-sensitive": true,
+                   "resource-type": ["image", "style-sheet", "script", "font",
+                                     "media", "raw", "document"]},
+         action: {type: "ignore-previous-rules"}}
+      ])
     ]);
-
-    test.done();
   },
 
   testElementIDattributeFormat: function(test)
   {
-    testRules(test,
-              ["###example", "test.com###EXAMPLE"],
-              ["[id=example]", "[id=EXAMPLE]"],
-              rules => rules.map(rule => rule.action.selector));
-
-    test.done();
+    runTest(test, [
+      testRules(test,
+                ["###example", "test.com###EXAMPLE"],
+                ["[id=example]", "[id=EXAMPLE]"],
+                rules => rules.map(rule => rule.action.selector))
+    ]);
   },
 
   testDomainWhitelisting: function(test)
   {
-    testRules(test, ["@@||example.com^$document"], [
-      {
-        trigger: {
-          "url-filter": ".*",
-          "if-domain": ["*example.com"]
-        },
-        action: {type: "ignore-previous-rules"}
-      }
-    ]);
-    testRules(test, ["@@||example.com^$document,image"], [
-      {
-        trigger: {
-          "url-filter": ".*",
-          "if-domain": ["*example.com"]
+    runTest(test, [
+      testRules(test, ["@@||example.com^$document"], [
+        {
+          trigger: {
+            "url-filter": ".*",
+            "if-domain": ["*example.com"]
+          },
+          action: {type: "ignore-previous-rules"}
+        }
+      ]),
+      testRules(test, ["@@||example.com^$document,image"], [
+        {
+          trigger: {
+            "url-filter": ".*",
+            "if-domain": ["*example.com"]
+          },
+          action: {type: "ignore-previous-rules"}
         },
-        action: {type: "ignore-previous-rules"}
-      },
-      {
-        trigger: {
-          "url-filter": "^https?://([^/]+\\.)?example\\.com([^-_.%a-z0-9].*)?$",
-          "url-filter-is-case-sensitive": true,
-          "resource-type": ["image"]
-        },
-        action: {type: "ignore-previous-rules"}
-      }
+        {
+          trigger: {
+            "url-filter":
+              "^https?://([^/]+\\.)?example\\.com([^-_.%a-z0-9].*)?$",
+            "url-filter-is-case-sensitive": true,
+            "resource-type": ["image"]
+          },
+          action: {type: "ignore-previous-rules"}
+        }
+      ]),
+      testRules(test, ["@@||example.com/path^$font,document"], [
+        {
+          trigger: {
+            "url-filter":
+              "^https?://([^/]+\\.)?example\\.com/path([^-_.%A-Za-z0-9].*)?$",
+            "resource-type": ["font"]
+          },
+          action: {type: "ignore-previous-rules"}
+        }
+      ])
     ]);
-    testRules(test, ["@@||example.com/path^$font,document"], [
-      {
-        trigger: {
-          "url-filter":
-            "^https?://([^/]+\\.)?example\\.com/path([^-_.%A-Za-z0-9].*)?$",
-          "resource-type": ["font"]
-        },
-        action: {type: "ignore-previous-rules"}
-      }
-    ]);
-
-    test.done();
   },
 
   testGenericblockExceptions: function(test)
   {
-    testRules(test, ["^ad.jpg|", "@@||example.com^$genericblock"],
-              [[undefined, ["*example.com"]]],
-              rules => rules.map(rule => [rule.trigger["if-domain"],
-                                          rule.trigger["unless-domain"]]));
-    testRules(test, ["^ad.jpg|$domain=test.com",
-                     "@@||example.com^$genericblock"],
-              [[["*test.com"], undefined]],
-              rules => rules.map(rule => [rule.trigger["if-domain"],
-                                          rule.trigger["unless-domain"]]));
-    testRules(test, ["^ad.jpg|$domain=~test.com",
-                     "@@||example.com^$genericblock"],
-              [[undefined, ["*test.com", "*example.com"]]],
-              rules => rules.map(rule => [rule.trigger["if-domain"],
-                                          rule.trigger["unless-domain"]]));
-
-    test.done();
+    runTest(test, [
+      testRules(test, ["^ad.jpg|", "@@||example.com^$genericblock"],
+                [[undefined, ["*example.com"]]],
+                rules => rules.map(rule => [rule.trigger["if-domain"],
+                                            rule.trigger["unless-domain"]])),
+      testRules(test, ["^ad.jpg|$domain=test.com",
+                       "@@||example.com^$genericblock"],
+                [[["*test.com"], undefined]],
+                rules => rules.map(rule => [rule.trigger["if-domain"],
+                                            rule.trigger["unless-domain"]])),
+      testRules(test, ["^ad.jpg|$domain=~test.com",
+                       "@@||example.com^$genericblock"],
+                [[undefined, ["*test.com", "*example.com"]]],
+                rules => rules.map(rule => [rule.trigger["if-domain"],
+                                            rule.trigger["unless-domain"]]))
+    ]);
   },
 
   testRuleOrdering: function(test)
   {
-    testRules(
-      test,
-      ["/ads.jpg", "@@example.com", "test.com#@#foo", "##bar"],
-      ["css-display-none", "block", "ignore-previous-rules"],
-      rules => rules.map(rule => rule.action.type)
-    );
-    testRules(
-      test,
-      ["@@example.com", "##bar", "/ads.jpg", "test.com#@#foo"],
-      ["css-display-none", "block", "ignore-previous-rules"],
-      rules => rules.map(rule => rule.action.type)
-    );
-
-    test.done();
+    runTest(test, [
+      testRules(
+        test,
+        ["/ads.jpg", "@@example.com", "test.com#@#foo", "##bar"],
+        ["css-display-none", "block", "ignore-previous-rules"],
+        rules => rules.map(rule => rule.action.type)
+      ),
+      testRules(
+        test,
+        ["@@example.com", "##bar", "/ads.jpg", "test.com#@#foo"],
+        ["css-display-none", "block", "ignore-previous-rules"],
+        rules => rules.map(rule => rule.action.type)
+      )
+    ]);
   },
 
   testRequestTypeMapping: function(test)
   {
-    testRules(
-      test,
-      ["1", "2$image", "3$stylesheet", "4$script", "5$font", "6$media",
-       "7$popup", "8$object", "9$object_subrequest", "10$xmlhttprequest",
-       "11$websocket", "12$webrtc",
-       "13$ping", "14$subdocument", "15$other", "16$IMAGE",
-       "17$script,PING,Popup", "18$~image"],
-      [["image", "style-sheet", "script", "font", "media", "raw"],
-       ["image"],
-       ["style-sheet"],
-       ["script"],
-       ["font"],
-       ["media"],
-       ["popup"],
-       ["media"],
-       ["raw"],
-       ["raw"],
-       ["raw"], // WebSocket
-       ["raw"], // WebRTC: STUN
-       ["raw"], // WebRTC: TURN
-       ["raw"],
-       ["raw"],
-       ["image"],
-       ["script", "popup", "raw" ],
-       ["style-sheet", "script", "font", "media", "raw"]],
-      rules => rules.map(rule => rule.trigger["resource-type"])
-    );
-
-    test.done();
+    runTest(test, [
+      testRules(
+        test,
+        ["1", "2$image", "3$stylesheet", "4$script", "5$font", "6$media",
+         "7$popup", "8$object", "9$object_subrequest", "10$xmlhttprequest",
+         "11$websocket", "12$webrtc",
+         "13$ping", "14$subdocument", "15$other", "16$IMAGE",
+         "17$script,PING,Popup", "18$~image"],
+        [["image", "style-sheet", "script", "font", "media", "raw"],
+         ["image"],
+         ["style-sheet"],
+         ["script"],
+         ["font"],
+         ["media"],
+         ["popup"],
+         ["media"],
+         ["raw"],
+         ["raw"],
+         ["raw"], // WebSocket
+         ["raw"], // WebRTC: STUN
+         ["raw"], // WebRTC: TURN
+         ["raw"],
+         ["raw"],
+         ["image"],
+         ["script", "popup", "raw" ],
+         ["style-sheet", "script", "font", "media", "raw"]],
+        rules => rules.map(rule => rule.trigger["resource-type"])
+      )
+    ]);
   },
 
   testUnsupportedfilters: function(test)
   {
-    // These types of filters are currently completely unsupported.
-    testRules(test, ["foo$sitekey=bar"], []);
-
-    test.done();
+    runTest(test, [
+      // These types of filters are currently completely unsupported.
+      testRules(test, ["foo$sitekey=bar"], [])
+    ]);
   },
 
   testFilterOptions: function(test)
   {
-    testRules(test, ["1$domain=foo.com"], ["*foo.com"],
-              rules => rules[0]["trigger"]["if-domain"]);
-    testRules(test, ["2$third-party"], ["third-party"],
-              rules => rules[0]["trigger"]["load-type"]);
-    testRules(test, ["foo$match_case"], true,
-              rules => rules[0]["trigger"]["url-filter-is-case-sensitive"]);
+    runTest(test, [
+      testRules(test, ["1$domain=foo.com"], ["*foo.com"],
+                rules => rules[0]["trigger"]["if-domain"]),
+      testRules(test, ["2$third-party"], ["third-party"],
+                rules => rules[0]["trigger"]["load-type"]),
+      testRules(test, ["foo$match_case"], true,
+                rules => rules[0]["trigger"]["url-filter-is-case-sensitive"]),
 
-    // Test subdomain exceptions.
-    testRules(test, ["1$domain=foo.com|~bar.foo.com"],
-              ["foo.com", "www.foo.com"],
-              rules => rules[0]["trigger"]["if-domain"]);
-    testRules(test, ["1$domain=foo.com|~www.foo.com"],
-              ["foo.com"],
-              rules => rules[0]["trigger"]["if-domain"]);
-
-    test.done();
+      // Test subdomain exceptions.
+      testRules(test, ["1$domain=foo.com|~bar.foo.com"],
+                ["foo.com", "www.foo.com"],
+                rules => rules[0]["trigger"]["if-domain"]),
+      testRules(test, ["1$domain=foo.com|~www.foo.com"],
+                ["foo.com"],
+                rules => rules[0]["trigger"]["if-domain"])
+    ]);
   },
 
   testUnicode: function(test)
   {
-    testRules(test, ["$domain=🐈.cat"], ["*xn--zn8h.cat"],
-              rules => rules[0]["trigger"]["if-domain"]);
-    testRules(test, ["||🐈"], "^[^:]+:(//)?([^/]+\\.)?xn--zn8h",
-              rules => rules[0]["trigger"]["url-filter"]);
-    testRules(test, ["🐈$domain=🐈.cat"], "^[^:]+:(//)?.*%F0%9F%90%88",
-              rules => rules[0]["trigger"]["url-filter"]);
-    testRules(test, ["🐈%F0%9F%90%88$domain=🐈.cat"],
-              "^[^:]+:(//)?.*%F0%9F%90%88%F0%9F%90%88",
-              rules => rules[0]["trigger"]["url-filter"]);
-    testRules(test, ["###🐈"], "[id=🐈]",
-              rules => rules[0]["action"]["selector"]);
-
-    test.done();
+    runTest(test, [
+      testRules(test, ["$domain=🐈.cat"], ["*xn--zn8h.cat"],
+                rules => rules[0]["trigger"]["if-domain"]),
+      testRules(test, ["||🐈"], "^[^:]+:(//)?([^/]+\\.)?xn--zn8h",
+                rules => rules[0]["trigger"]["url-filter"]),
+      testRules(test, ["🐈$domain=🐈.cat"], "^[^:]+:(//)?.*%F0%9F%90%88",
+                rules => rules[0]["trigger"]["url-filter"]),
+      testRules(test, ["🐈%F0%9F%90%88$domain=🐈.cat"],
+                "^[^:]+:(//)?.*%F0%9F%90%88%F0%9F%90%88",
+                rules => rules[0]["trigger"]["url-filter"]),
+      testRules(test, ["###🐈"], "[id=🐈]",
+                rules => rules[0]["action"]["selector"])
+    ]);
   },
 
   testWebSocket: function(test)
   {
-    testRules(test, ["foo$websocket"], [
-      {trigger: {"url-filter": "^wss?://.*foo", "resource-type": ["raw"]},
-       action: {type: "block"}}
+    runTest(test, [
+      testRules(test, ["foo$websocket"], [
+        {trigger: {"url-filter": "^wss?://.*foo", "resource-type": ["raw"]},
+         action: {type: "block"}}
+      ])
     ]);
-
-    test.done();
   },
 
   testWebRTC: function(test)
   {
-    testRules(test, ["foo$webrtc"], [
-      {trigger: {"url-filter": "^stuns?:.*foo", "resource-type": ["raw"]},
-       action: {type: "block"}},
-      {trigger: {"url-filter": "^turns?:.*foo", "resource-type": ["raw"]},
-       action: {type: "block"}}
+    runTest(test, [
+      testRules(test, ["foo$webrtc"], [
+        {trigger: {"url-filter": "^stuns?:.*foo", "resource-type": ["raw"]},
+         action: {type: "block"}},
+        {trigger: {"url-filter": "^turns?:.*foo", "resource-type": ["raw"]},
+         action: {type: "block"}}
+      ])
     ]);
+  },
 
-    test.done();
+  testMerging: function(test)
+  {
+    runTest(test, [
+      // Single character substitutions, deletions, and insertions.
+      testRules(test, ["/ads", "/adv"], ["^[^:]+:(//)?.*/ad[sv]"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/ads", "/advs"], ["^[^:]+:(//)?.*/adv?s"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/advs", "/ads"], ["^[^:]+:(//)?.*/adv?s"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adts", "/advs", "/ads"], ["^[^:]+:(//)?.*/ad[tv]?s"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/ads", "/adts", "/advs"], ["^[^:]+:(//)?.*/ad[tv]?s"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adts", "/ads", "/advs"], ["^[^:]+:(//)?.*/ad[tv]?s"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/ax", "/adx", "/adsx", "/advx"],
+                ["^[^:]+:(//)?.*/ax", "^[^:]+:(//)?.*/ad[sv]?x"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adx", "/ax", "/adsx", "/advx"],
+                ["^[^:]+:(//)?.*/ax", "^[^:]+:(//)?.*/ad[sv]?x"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adsx", "/advx", "/adx", "/ax"],
+                ["^[^:]+:(//)?.*/ad[sv]?x", "^[^:]+:(//)?.*/ax"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adsx", "/advx", "/ax", "/adx"],
+                ["^[^:]+:(//)?.*/ad[sv]?x", "^[^:]+:(//)?.*/ax"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/ad-", "/a-", "/ads-", "/adv-", "/adx-"],
+                ["^[^:]+:(//)?.*/a-", "^[^:]+:(//)?.*/ad[svx]?-"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/ads-", "/a-", "/ad-", "/adv-", "/adx-"],
+                ["^[^:]+:(//)?.*/ad[svx]?-", "^[^:]+:(//)?.*/a-"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+
+      // Multiple character deletions and insertions.
+      testRules(test, ["/ads", "/adxis"],
+                ["^[^:]+:(//)?.*/ad(xi)?s"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adxsi", "/xsi"],
+                ["^[^:]+:(//)?.*/(ad)?xsi"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adxsi", "/ai"],
+                ["^[^:]+:(//)?.*/a(dxs)?i"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+
+      // Both single and multiple character edits combined.
+      testRules(test, ["/adq", "/adxsiq", "/xsiq", "/axsiq", "/bxsiq"],
+                ["^[^:]+:(//)?.*/ad(xsi)?q", "^[^:]+:(//)?.*/[ab]?xsiq"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+
+      testRules(test, ["/adsq", "/aq", "/adq", "/advq", "/adxq", "/adxsq"],
+                ["^[^:]+:(//)?.*/ad[svx]?q", "^[^:]+:(//)?.*/a(dxs)?q"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adxsq", "/aq", "/adq", "/adsq", "/advq", "/adxq"],
+                ["^[^:]+:(//)?.*/a(dxs)?q", "^[^:]+:(//)?.*/ad[svx]?q"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adxsq", "/aq", "/adsq", "/adq", "/advq", "/adxq"],
+                ["^[^:]+:(//)?.*/a(dxs)?q", "^[^:]+:(//)?.*/ad[svx]?q"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adxsq", "/aq", "/adsq", "/advq", "/adq", "/adxq"],
+                ["^[^:]+:(//)?.*/a(dxs)?q", "^[^:]+:(//)?.*/ad[svx]?q"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adsxiq", "/adxsq", "/aq", "/adsq", "/advq", "/adq",
+                       "/adxq"],
+                ["^[^:]+:(//)?.*/a(dsxi)?q", "^[^:]+:(//)?.*/adxsq",
+                 "^[^:]+:(//)?.*/ad[svx]?q"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adxsiq", "/adsxiq", "/adxsq", "/aq", "/adsq", "/advq",
+                       "/adq", "/adxq"],
+                ["^[^:]+:(//)?.*/adxsi?q", "^[^:]+:(//)?.*/a(dsxi)?q",
+                 "^[^:]+:(//)?.*/ad[svx]?q"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+
+      // Given the 6 rules "adsi", "bdsi", "advi", "bdvi", "adxi", and "bdxi",
+      // we want the 2 rules "ad[svx]i" and "bd[svx]i", not the 3 rules
+      // "[ab]dsi", "[ab]dvi", and "[ab]dxi"
+      testRules(test, ["/adsi", "/bdsi", "/advi", "/bdvi", "/adxi", "/bdxi"],
+                ["^[^:]+:(//)?.*/ad[svx]i", "^[^:]+:(//)?.*/bd[svx]i"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/adsi", "/bdsi", "/advi", "/bdvi", "/bdxi"],
+                ["^[^:]+:(//)?.*/ad[sv]i", "^[^:]+:(//)?.*/bd[svx]i"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+
+      // Make sure there's no merge where there are special characters in the
+      // delta.
+      testRules(test, ["/ads?q", "/adsq"],
+                ["^[^:]+:(//)?.*/ads\\?q", "^[^:]+:(//)?.*/adsq"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/ads?", "/ads-"],
+                ["^[^:]+:(//)?.*/ads\\?", "^[^:]+:(//)?.*/ads-"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+      testRules(test, ["/ads?-", "/ads-"],
+                ["^[^:]+:(//)?.*/ads\\?-", "^[^:]+:(//)?.*/ads-"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"}),
+
+      // Redundant rules should be discarded.
+      testRules(test, ["/ad", "/ads", "/advertisement"],
+                ["^[^:]+:(//)?.*/ad"],
+                rules => rules.map(rule => rule.trigger["url-filter"]),
+                {merge: "all"})
+    ]);
   }
 };