1 files changed, 85 insertions, 0 deletions
diff --git a/js/xpconnect/tests/unit/test_import_devtools_loader.js b/js/xpconnect/tests/unit/test_import_devtools_loader.js
new file mode 100644
index 0000000000..d7e6fe42f6
--- /dev/null
+++ b/js/xpconnect/tests/unit/test_import_devtools_loader.js
@@ -0,0 +1,85 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+const { addDebuggerToGlobal } = ChromeUtils.importESModule(
+  "resource://gre/modules/jsdebugger.sys.mjs"
+);
+addDebuggerToGlobal(this);
+
+const ESM_URL = "resource://test/es6module_devtoolsLoader.sys.mjs";
+
+// Toggle the following pref to enable Cu.getModuleImportStack()
+if (AppConstants.NIGHTLY_BUILD) {
+  Services.prefs.setBoolPref("browser.startup.record", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("browser.startup.record");
+  });
+}
+
+add_task(async function testDevToolsModuleLoader() {
+  const dbg = new Debugger();
+
+  const sharedGlobal = Cu.getGlobalForObject(Services);
+  const sharedPrincipal = Cu.getObjectPrincipal(sharedGlobal);
+
+  info("Test importing in the regular shared loader");
+  const ns = ChromeUtils.importESModule(ESM_URL);
+  Assert.equal(ns.x, 0);
+  ns.increment();
+  Assert.equal(ns.x, 1);
+  const nsGlobal = Cu.getGlobalForObject(ns);
+  const nsPrincipal = Cu.getObjectPrincipal(nsGlobal);
+  Assert.equal(nsGlobal, sharedGlobal, "Without any parameter, importESModule load in the shared JSM global");
+  Assert.equal(nsPrincipal, sharedPrincipal);
+  Assert.ok(nsPrincipal.isSystemPrincipal);
+  info("Global of ESM loaded in the shared loader can be inspected by the Debugger");
+  dbg.addDebuggee(nsGlobal);
+  Assert.ok(true, "The global is accepted by the Debugger API");
+
+  const ns1 = ChromeUtils.importESModule(ESM_URL, { loadInDevToolsLoader : false });
+  Assert.equal(ns1, ns, "Passing loadInDevToolsLoader=false from the shared JSM global is equivalent to regular importESModule");
+
+  info("Test importing in the devtools loader");
+  const ns2 = ChromeUtils.importESModule(ESM_URL, { loadInDevToolsLoader: true });
+  Assert.equal(ns2.x, 0, "We get a new module instance with a new incremented number");
+  Assert.notEqual(ns2, ns, "We imported a new instance of the module");
+  Assert.notEqual(ns2.importedObject, ns.importedObject, "The two module instances expose distinct objects");
+  Assert.equal(ns2.importESModuleTrue, ns2.importedObject, "When using loadInDevToolsLoader:true from a devtools global, we keep loading in the same loader");
+  Assert.equal(ns2.importESModuleNull, ns2.importedObject, "When having an undefined loadInDevToolsLoader from a devtools global, we keep loading in the same loader");
+  Assert.equal(ns2.importESModuleNull2, ns2.importedObject, "When having no optional argument at all, we keep loading in the same loader");
+  Assert.equal(ns2.importESModuleFalse, ns.importedObject, "When passing an explicit loadInDevToolsLoader:false, we load in the shared global, even from a devtools global");
+  Assert.equal(ns2.importLazy(), ns2.importedObject, "ChromeUtils.defineESModuleGetters imports will follow the contextual loader");
+
+  info("When using the devtools loader, we load in a distinct global, but the same compartment");
+  const ns2Global = Cu.getGlobalForObject(ns2);
+  const ns2Principal = Cu.getObjectPrincipal(ns2Global);
+  Assert.notEqual(ns2Global, sharedGlobal, "The module is loaded in a distinct global");
+  Assert.equal(ns2Principal, sharedPrincipal, "The principal is still the shared system principal");
+  Assert.equal(Cu.getGlobalForObject(ns2.importedObject), ns2Global, "Nested dependencies are also loaded in the same devtools global");
+  Assert.throws(() => dbg.addDebuggee(ns2Global), /TypeError: passing non-debuggable global to addDebuggee/,
+    "Global os ESM loaded in the devtools loader can't be inspected by the Debugee");
+
+  info("Re-import the same module in the devtools loader");
+  const ns3 = ChromeUtils.importESModule(ESM_URL, { loadInDevToolsLoader: true });
+  Assert.equal(ns3, ns2, "We import the exact same module");
+  Assert.equal(ns3.importedObject, ns2.importedObject, "The two module expose the same objects");
+
+  info("Import a module only from the devtools loader");
+  const ns4 = ChromeUtils.importESModule("resource://test/es6module_devtoolsLoader_only.js", { loadInDevToolsLoader: true });
+  const ns4Global = Cu.getGlobalForObject(ns4);
+  Assert.equal(ns4Global, ns2Global, "The module is loaded in the same devtools global");
+
+  // getModuleImportStack only works on nightly builds
+  if (AppConstants.NIGHTLY_BUILD) {
+    info("Assert the behavior of getModuleImportStack on modules loaded in the devtools loader");
+    Assert.ok(Cu.getModuleImportStack(ESM_URL).includes("testDevToolsModuleLoader"));
+    Assert.ok(Cu.getModuleImportStack("resource://test/es6module_devtoolsLoader.js").includes("testDevToolsModuleLoader"));
+    Assert.ok(Cu.getModuleImportStack("resource://test/es6module_devtoolsLoader.js").includes(ESM_URL));
+    // Previous import stack were for module loaded via the shared jsm loader.
+    // Let's also assert that we get stack traces for modules loaded via the devtools loader.
+    Assert.ok(Cu.getModuleImportStack("resource://test/es6module_devtoolsLoader_only.js").includes("testDevToolsModuleLoader"));
+  }
+});