1 files changed, 46 insertions, 0 deletions
diff --git a/devtools/client/debugger/test/mochitest/browser_dbg-debug-line.js b/devtools/client/debugger/test/mochitest/browser_dbg-debug-line.js
new file mode 100644
index 0000000000..ab13a1ee50
--- /dev/null
+++ b/devtools/client/debugger/test/mochitest/browser_dbg-debug-line.js
@@ -0,0 +1,46 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
+
+// Test ensures zombie debug lines do not persist
+// https://github.com/firefox-devtools/debugger/issues/7755
+
+"use strict";
+
+add_task(async function () {
+  // Load test files
+  const dbg = await initDebugger("doc-sources.html");
+  await waitForSources(dbg, "simple1.js", "simple2.js");
+
+  // Add breakpoint to debug-line-2
+  await selectSource(dbg, "simple2.js");
+  await addBreakpoint(dbg, "simple2.js", 5);
+
+  // Trigger the breakpoint ane ensure we're paused
+  invokeInTab("main");
+  await waitForPaused(dbg);
+  await waitForDispatch(dbg.store, "ADD_INLINE_PREVIEW");
+
+  // Scroll element into view
+  findElement(dbg, "frame", 2).focus();
+
+  // Click the call stack to get to debugger-line-1
+  const dispatched = waitForDispatch(dbg.store, "ADD_INLINE_PREVIEW");
+  await clickElement(dbg, "frame", 2);
+  await dispatched;
+  await waitForRequestsToSettle(dbg);
+  await waitForSelectedSource(dbg, "simple1.js");
+
+  // Resume, which ends all pausing and would trigger the problem
+  await resume(dbg);
+
+  // Select the source that had the initial debug line
+  await selectSource(dbg, "simple2.js");
+
+  info("Ensuring there's no zombie debug line");
+  is(
+    findAllElements(dbg, "debugLine").length,
+    0,
+    "Debug line no longer exists!"
+  );
+});