Bug 1320391 - Part 2: Add a test that old PartialSHistories are cleaned up correctly, r=ehsan

MozReview-Commit-ID: 4Jd5UbmdEru

--HG--
extra : rebase_source : 42407f987d2b6e7c3ed3a91e9f75e3911e292091

docshell/test/browser/browser.ini

@@ -95,3 +95,5 @@ skip-if = true # Bug 1220415
 skip-if = !e10s
 [browser_grouped_shistory_crossproc.js]
 skip-if = !e10s
+[browser_grouped_shistory_bfcache_cleaning.js]
+skip-if = !e10s

docshell/test/browser/browser_grouped_shistory_bfcache_cleaning.js

@@ -0,0 +1,61 @@
+add_task(function* () {
+  yield SpecialPowers.pushPrefEnv({
+    set: [["browser.groupedhistory.enabled", true]]
+  });
+
+  // Wait for a process change and then fulfil the promise.
+  function awaitProcessChange(browser) {
+    return new Promise(resolve => {
+      browser.addEventListener("BrowserChangedProcess", function bcp(e) {
+        browser.removeEventListener("BrowserChangedProcess", bcp);
+        ok(true, "The browser changed process!");
+        resolve();
+      });
+    });
+  }
+
+  function isAlive(tab) {
+    return tab.linkedBrowser &&
+      tab.linkedBrowser.frameLoader &&
+      !tab.linkedBrowser.frameLoader.isDead;
+  }
+
+  yield BrowserTestUtils.withNewTab({ gBrowser, url: "data:text/html,a" }, function* (browser1) {
+    // Set up the grouped SHEntry setup
+    let tab2 = gBrowser.loadOneTab("data:text/html,b", {
+      referrerPolicy: Ci.nsIHttpChannel.REFERRER_POLICY_DEFAULT,
+      allowThirdPartyFixup: true,
+      relatedToCurrent: true,
+      isPrerendered: true,
+    });
+    yield BrowserTestUtils.browserLoaded(tab2.linkedBrowser);
+    browser1.frameLoader.appendPartialSessionHistoryAndSwap(
+      tab2.linkedBrowser.frameLoader);
+    yield awaitProcessChange(browser1);
+    ok(isAlive(tab2));
+
+    // Load some URIs and make sure that we lose the old process once we are 3 history entries away.
+    browser1.loadURI("data:text/html,c", null, null);
+    yield BrowserTestUtils.browserLoaded(browser1);
+    ok(isAlive(tab2), "frameloader should still be alive");
+    browser1.loadURI("data:text/html,d", null, null);
+    yield BrowserTestUtils.browserLoaded(browser1);
+    ok(isAlive(tab2), "frameloader should still be alive");
+    browser1.loadURI("data:text/html,e", null, null);
+    yield BrowserTestUtils.browserLoaded(browser1);
+    ok(isAlive(tab2), "frameloader should still be alive");
+
+    // The 4th navigation should kill the frameloader
+    browser1.loadURI("data:text/html,f", null, null);
+    yield new Promise(resolve => {
+      tab2.addEventListener("TabClose", function f() {
+        tab2.removeEventListener("TabClose", f);
+        ok(true, "The tab is being closed!\n");
+        resolve();
+      });
+    });
+    // We don't check for !isAlive() as TabClose is called during
+    // _beginRemoveTab, which means that the frameloader may not be dead yet. We
+    // avoid races by not checking.
+  });
+});