1 files changed, 77 insertions, 0 deletions
diff --git a/devtools/client/webconsole/test/browser/browser_jsterm_await_assignments.js b/devtools/client/webconsole/test/browser/browser_jsterm_await_assignments.js
new file mode 100644
index 0000000000..6eb1ee53ed
--- /dev/null
+++ b/devtools/client/webconsole/test/browser/browser_jsterm_await_assignments.js
@@ -0,0 +1,77 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Test that top-level await expressions work as expected.
+
+"use strict";
+
+const TEST_URI =
+  "data:text/html;charset=utf-8,<!DOCTYPE html>Web Console test top-level await bindings";
+
+add_task(async function () {
+  // Enable await mapping.
+  await pushPref("devtools.debugger.features.map-await-expression", true);
+  const hud = await openNewTabAndConsole(TEST_URI);
+
+  info("Check that declaring a let variable does not create a global property");
+  await executeAndWaitForResultMessage(
+    hud,
+    `let bazA = await new Promise(r => setTimeout(() => r("local-bazA"), 10))`,
+    "local-bazA"
+  );
+  await checkVariable(hud, "bazA");
+
+  info(
+    "Check that declaring a const variable does not create a global property"
+  );
+  await executeAndWaitForResultMessage(
+    hud,
+    `const bazB = await new Promise(r => setTimeout(() => r("local-bazB"), 10))`,
+    "local-bazB"
+  );
+  await checkVariable(hud, "bazB");
+
+  info("Check that complex variable declarations work as expected");
+  await executeAndWaitForResultMessage(
+    hud,
+    `
+    let bazC = "local-bazC", bazD, bazE = "local-bazE";
+    bazD = await new Promise(r => setTimeout(() => r("local-bazD"), 10));
+    let {
+      a: bazF,
+      b: {
+        c: {
+          bazG = "local-bazG",
+          d: bazH,
+          e: [bazI, bazJ = "local-bazJ"]
+        },
+        d: bazK = "local-bazK"
+      }
+    } = await ({
+      a: "local-bazF",
+      b: {
+        c: {
+          d: "local-bazH",
+          e: ["local-bazI"]
+        }
+      }
+    });`,
+    ""
+  );
+  await checkVariable(hud, "bazC");
+  await checkVariable(hud, "bazD");
+  await checkVariable(hud, "bazE");
+  await checkVariable(hud, "bazF");
+  await checkVariable(hud, "bazG");
+  await checkVariable(hud, "bazH");
+  await checkVariable(hud, "bazI");
+  await checkVariable(hud, "bazJ");
+  await checkVariable(hud, "bazK");
+});
+
+async function checkVariable(hud, varName) {
+  await executeAndWaitForResultMessage(hud, `window.${varName}`, `undefined`);
+  ok(true, `The ${varName} assignment did not create a global variable`);
+  await executeAndWaitForResultMessage(hud, varName, `"local-${varName}"`);
+  ok(true, `"${varName}" has the expected value`);
+}