1 files changed, 129 insertions, 0 deletions
diff --git a/devtools/shared/commands/resource/tests/browser_resources_root_node.js b/devtools/shared/commands/resource/tests/browser_resources_root_node.js
new file mode 100644
index 0000000000..67ef5efd90
--- /dev/null
+++ b/devtools/shared/commands/resource/tests/browser_resources_root_node.js
@@ -0,0 +1,129 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test the ResourceCommand API around ROOT_NODE
+
+/**
+ * The original test still asserts some scenarios using several watchRootNode
+ * call sites, which is not something we intend to support at the moment in the
+ * resource command.
+ *
+ * Otherwise this test checks the basic behavior of the resource when reloading
+ * an empty page.
+ */
+add_task(async function () {
+  // Open a test tab
+  const tab = await addTab("data:text/html,Root Node tests");
+
+  const { client, resourceCommand, targetCommand } = await initResourceCommand(
+    tab
+  );
+
+  const browser = gBrowser.selectedBrowser;
+
+  info("Call watchResources([ROOT_NODE], ...)");
+  let onAvailableCounter = 0;
+  const onAvailable = resources => (onAvailableCounter += resources.length);
+  await resourceCommand.watchResources([resourceCommand.TYPES.ROOT_NODE], {
+    onAvailable,
+  });
+
+  info("Wait until onAvailable has been called");
+  await waitUntil(() => onAvailableCounter === 1);
+  is(onAvailableCounter, 1, "onAvailable has been called 1 time");
+
+  info("Reload the selected browser");
+  browser.reload();
+
+  info(
+    "Wait until the watchResources([ROOT_NODE], ...) callback has been called"
+  );
+  await waitUntil(() => onAvailableCounter === 2);
+
+  is(onAvailableCounter, 2, "onAvailable has been called 2 times");
+
+  info("Call unwatchResources([ROOT_NODE], ...) for the onAvailable callback");
+  resourceCommand.unwatchResources([resourceCommand.TYPES.ROOT_NODE], {
+    onAvailable,
+  });
+
+  info("Reload the selected browser");
+  const reloaded = BrowserTestUtils.browserLoaded(browser);
+  browser.reload();
+  await reloaded;
+
+  is(
+    onAvailableCounter,
+    2,
+    "onAvailable was not called after calling unwatchResources"
+  );
+
+  // Cleanup
+  targetCommand.destroy();
+  await client.close();
+});
+
+/**
+ * Test that the watchRootNode API provides the expected node fronts.
+ */
+add_task(async function testRootNodeFrontIsCorrect() {
+  const tab = await addTab("data:text/html,<div id=div1>");
+
+  const { client, resourceCommand, targetCommand } = await initResourceCommand(
+    tab
+  );
+  const browser = gBrowser.selectedBrowser;
+
+  info("Call watchResources([ROOT_NODE], ...)");
+
+  let rootNodeResolve;
+  let rootNodePromise = new Promise(r => (rootNodeResolve = r));
+  const onAvailable = ([rootNodeFront]) => rootNodeResolve(rootNodeFront);
+  await resourceCommand.watchResources([resourceCommand.TYPES.ROOT_NODE], {
+    onAvailable,
+  });
+
+  info("Wait until onAvailable has been called");
+  const root1 = await rootNodePromise;
+  ok(!!root1, "onAvailable has been called with a valid argument");
+  is(
+    root1.resourceType,
+    resourceCommand.TYPES.ROOT_NODE,
+    "The resource has the expected type"
+  );
+
+  info("Check we can query an expected node under the retrieved root");
+  const div1 = await root1.walkerFront.querySelector(root1, "div");
+  is(div1.getAttribute("id"), "div1", "Correct root node retrieved");
+
+  info("Reload the selected browser");
+  rootNodePromise = new Promise(r => (rootNodeResolve = r));
+  browser.reload();
+
+  const root2 = await rootNodePromise;
+  Assert.notStrictEqual(
+    root1,
+    root2,
+    "onAvailable has been called with a different node front after reload"
+  );
+
+  info("Navigate to another URL");
+  rootNodePromise = new Promise(r => (rootNodeResolve = r));
+  BrowserTestUtils.startLoadingURIString(
+    browser,
+    `data:text/html,<div id=div3>`
+  );
+  const root3 = await rootNodePromise;
+  info("Check we can query an expected node under the retrieved root");
+  const div3 = await root3.walkerFront.querySelector(root3, "div");
+  is(div3.getAttribute("id"), "div3", "Correct root node retrieved");
+
+  // Cleanup
+  resourceCommand.unwatchResources([resourceCommand.TYPES.ROOT_NODE], {
+    onAvailable,
+  });
+  targetCommand.destroy();
+  await client.close();
+});