1 files changed, 134 insertions, 0 deletions
diff --git a/browser/components/extensions/test/browser/browser_ext_tabs_executeScript_runAt.js b/browser/components/extensions/test/browser/browser_ext_tabs_executeScript_runAt.js
new file mode 100644
index 0000000000..bab0182a3f
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+++ b/browser/components/extensions/test/browser/browser_ext_tabs_executeScript_runAt.js
@@ -0,0 +1,134 @@
+/* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim: set sts=2 sw=2 et tw=80: */
+"use strict";
+
+/**
+ * These tests ensure that the runAt argument to tabs.executeScript delays
+ * script execution until the document has reached the correct state.
+ *
+ * Since tests of this nature are especially race-prone, it relies on a
+ * server-JS script to delay the completion of our test page's load cycle long
+ * enough for us to attempt to load our scripts in the earlies phase we support.
+ *
+ * And since we can't actually rely on that timing, it retries any attempts that
+ * fail to load as early as expected, but don't load at any illegal time.
+ */
+
+add_task(async function testExecuteScript() {
+  let tab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    "about:blank",
+    true
+  );
+
+  async function background() {
+    let tab;
+
+    const BASE =
+      "http://mochi.test:8888/browser/browser/components/extensions/test/browser/";
+    const URL = BASE + "file_slowed_document.sjs";
+
+    const MAX_TRIES = 10;
+
+    let onUpdatedPromise = (tabId, url, status) => {
+      return new Promise(resolve => {
+        browser.tabs.onUpdated.addListener(function listener(_, changed, tab) {
+          if (tabId == tab.id && changed.status == status && tab.url == url) {
+            browser.tabs.onUpdated.removeListener(listener);
+            resolve();
+          }
+        });
+      });
+    };
+
+    try {
+      [tab] = await browser.tabs.query({ active: true, currentWindow: true });
+
+      let success = false;
+      for (let tries = 0; !success && tries < MAX_TRIES; tries++) {
+        let url = `${URL}?with-iframe&r=${Math.random()}`;
+
+        let loadingPromise = onUpdatedPromise(tab.id, url, "loading");
+        let completePromise = onUpdatedPromise(tab.id, url, "complete");
+
+        // TODO: Test allFrames and frameId.
+
+        await browser.tabs.update({ url });
+        await loadingPromise;
+
+        let states = await Promise.all(
+          [
+            // Send the executeScript requests in the reverse order that we expect
+            // them to execute in, to avoid them passing only because of timing
+            // races.
+            browser.tabs.executeScript({
+              code: "document.readyState",
+              // Testing default `runAt`.
+            }),
+            browser.tabs.executeScript({
+              code: "document.readyState",
+              runAt: "document_idle",
+            }),
+            browser.tabs.executeScript({
+              code: "document.readyState",
+              runAt: "document_end",
+            }),
+            browser.tabs.executeScript({
+              code: "document.readyState",
+              runAt: "document_start",
+            }),
+          ].reverse()
+        );
+
+        browser.test.log(`Got states: ${states}`);
+
+        // Make sure that none of our scripts executed earlier than expected,
+        // regardless of retries.
+        browser.test.assertTrue(
+          states[1] == "interactive" || states[1] == "complete",
+          `document_end state is valid: ${states[1]}`
+        );
+        browser.test.assertTrue(
+          states[2] == "interactive" || states[2] == "complete",
+          `document_idle state is valid: ${states[2]}`
+        );
+
+        // If we have the earliest valid states for each script, we're done.
+        // Otherwise, try again.
+        success =
+          states[0] == "loading" &&
+          states[1] == "interactive" &&
+          states[2] == "interactive" &&
+          states[3] == "interactive";
+
+        await completePromise;
+      }
+
+      browser.test.assertTrue(
+        success,
+        "Got the earliest expected states at least once"
+      );
+
+      browser.test.notifyPass("executeScript-runAt");
+    } catch (e) {
+      browser.test.fail(`Error: ${e} :: ${e.stack}`);
+      browser.test.notifyFail("executeScript-runAt");
+    }
+  }
+
+  let extension = ExtensionTestUtils.loadExtension({
+    manifest: {
+      permissions: ["http://mochi.test/", "tabs"],
+    },
+
+    background,
+  });
+
+  await extension.startup();
+
+  await extension.awaitFinish("executeScript-runAt");
+
+  await extension.unload();
+
+  BrowserTestUtils.removeTab(tab);
+});