1 files changed, 139 insertions, 0 deletions
diff --git a/devtools/server/tracer/tests/xpcshell/test_tracer.js b/devtools/server/tracer/tests/xpcshell/test_tracer.js
new file mode 100644
index 0000000000..4150944d88
--- /dev/null
+++ b/devtools/server/tracer/tests/xpcshell/test_tracer.js
@@ -0,0 +1,139 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const { addTracingListener, removeTracingListener, startTracing, stopTracing } =
+  ChromeUtils.import("resource://devtools/server/tracer/tracer.jsm");
+
+add_task(async function () {
+  // Because this test uses evalInSandbox, we need to tweak the following prefs
+  Services.prefs.setBoolPref(
+    "security.allow_parent_unrestricted_js_loads",
+    true
+  );
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("security.allow_parent_unrestricted_js_loads");
+  });
+});
+
+add_task(async function testTracingContentGlobal() {
+  const toggles = [];
+  const frames = [];
+  const listener = {
+    onTracingToggled(state) {
+      toggles.push(state);
+    },
+    onTracingFrame(frameInfo) {
+      frames.push(frameInfo);
+    },
+  };
+
+  info("Register a tracing listener");
+  addTracingListener(listener);
+
+  const sandbox = Cu.Sandbox("https://example.com");
+  Cu.evalInSandbox("function bar() {}; function foo() {bar()};", sandbox);
+
+  info("Start tracing");
+  startTracing({ global: sandbox, prefix: "testContentPrefix" });
+  Assert.equal(toggles.length, 1);
+  Assert.equal(toggles[0], true);
+
+  info("Call some code");
+  sandbox.foo();
+
+  Assert.equal(frames.length, 2);
+  const lastFrame = frames.pop();
+  const beforeLastFrame = frames.pop();
+  Assert.equal(beforeLastFrame.depth, 0);
+  Assert.equal(beforeLastFrame.formatedDisplayName, "λ foo");
+  Assert.equal(beforeLastFrame.prefix, "testContentPrefix: ");
+  Assert.ok(beforeLastFrame.frame);
+  Assert.equal(lastFrame.depth, 1);
+  Assert.equal(lastFrame.formatedDisplayName, "λ bar");
+  Assert.equal(lastFrame.prefix, "testContentPrefix: ");
+  Assert.ok(lastFrame.frame);
+
+  info("Stop tracing");
+  stopTracing();
+  Assert.equal(toggles.length, 2);
+  Assert.equal(toggles[1], false);
+
+  info("Recall code after stop, no more traces are logged");
+  sandbox.foo();
+  Assert.equal(frames.length, 0);
+
+  info("Start tracing again, and recall code");
+  startTracing({ global: sandbox, prefix: "testContentPrefix" });
+  sandbox.foo();
+  info("New traces are logged");
+  Assert.equal(frames.length, 2);
+
+  info("Unregister the listener and recall code");
+  removeTracingListener(listener);
+  sandbox.foo();
+  info("No more traces are logged");
+  Assert.equal(frames.length, 2);
+
+  info("Stop tracing");
+  stopTracing();
+});
+
+add_task(async function testTracingJSMGlobal() {
+  // We have to register the listener code in a sandbox, i.e. in a distinct global
+  // so that we aren't creating traces when tracer calls it. (and cause infinite loops)
+  const systemPrincipal = Services.scriptSecurityManager.getSystemPrincipal();
+  const listenerSandbox = Cu.Sandbox(systemPrincipal);
+  Cu.evalInSandbox(
+    "new " +
+      function () {
+        globalThis.toggles = [];
+        globalThis.frames = [];
+        globalThis.listener = {
+          onTracingToggled(state) {
+            globalThis.toggles.push(state);
+          },
+          onTracingFrame(frameInfo) {
+            globalThis.frames.push(frameInfo);
+          },
+        };
+      },
+    listenerSandbox
+  );
+
+  info("Register a tracing listener");
+  addTracingListener(listenerSandbox.listener);
+
+  info("Start tracing");
+  startTracing({ global: null, prefix: "testPrefix" });
+  Assert.equal(listenerSandbox.toggles.length, 1);
+  Assert.equal(listenerSandbox.toggles[0], true);
+
+  info("Call some code");
+  function bar() {}
+  function foo() {
+    bar();
+  }
+  foo();
+
+  // Note that the tracer will record the two Assert.equal and the info calls.
+  // So only assert the last two frames.
+  const lastFrame = listenerSandbox.frames.at(-1);
+  const beforeLastFrame = listenerSandbox.frames.at(-2);
+  Assert.equal(beforeLastFrame.depth, 0);
+  Assert.equal(beforeLastFrame.formatedDisplayName, "λ foo");
+  Assert.equal(beforeLastFrame.prefix, "testPrefix: ");
+  Assert.ok(beforeLastFrame.frame);
+  Assert.equal(lastFrame.depth, 1);
+  Assert.equal(lastFrame.formatedDisplayName, "λ bar");
+  Assert.equal(lastFrame.prefix, "testPrefix: ");
+  Assert.ok(lastFrame.frame);
+
+  info("Stop tracing");
+  stopTracing();
+  Assert.equal(listenerSandbox.toggles.length, 2);
+  Assert.equal(listenerSandbox.toggles[1], false);
+
+  removeTracingListener(listenerSandbox.listener);
+});