1 files changed, 88 insertions, 0 deletions
diff --git a/devtools/shared/heapsnapshot/tests/xpcshell/test_HeapSnapshot_deepStack_01.js b/devtools/shared/heapsnapshot/tests/xpcshell/test_HeapSnapshot_deepStack_01.js
new file mode 100644
index 0000000000..7f88d0a142
--- /dev/null
+++ b/devtools/shared/heapsnapshot/tests/xpcshell/test_HeapSnapshot_deepStack_01.js
@@ -0,0 +1,88 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+"use strict";
+
+// Test that we can save a core dump with very deep allocation stacks and read
+// it back into a HeapSnapshot.
+
+function stackDepth(stack) {
+  return stack ? 1 + stackDepth(stack.parent) : 0;
+}
+
+function run_test() {
+  Services.prefs.setBoolPref(
+    "security.allow_parent_unrestricted_js_loads",
+    true
+  );
+  Services.prefs.setBoolPref("security.allow_eval_with_system_principal", true);
+  Services.prefs.setBoolPref("security.allow_eval_in_parent_process", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("security.allow_parent_unrestricted_js_loads");
+    Services.prefs.clearUserPref("security.allow_eval_with_system_principal");
+    Services.prefs.clearUserPref("security.allow_eval_in_parent_process");
+  });
+
+  // Create a Debugger observing a debuggee's allocations.
+  const debuggee = new Cu.Sandbox(null);
+  const dbg = new Debugger(debuggee);
+  dbg.memory.trackingAllocationSites = true;
+
+  // Allocate some objects in the debuggee that will have their allocation
+  // stacks recorded by the Debugger.
+
+  debuggee.eval("this.objects = []");
+  debuggee.eval(
+    function recursiveAllocate(n) {
+      if (n <= 0) {
+        return;
+      }
+
+      // Make sure to recurse before pushing the object so that when TCO is
+      // implemented sometime in the future, it doesn't invalidate this test.
+      recursiveAllocate(n - 1);
+      this.objects.push({});
+    }.toString()
+  );
+  debuggee.eval("recursiveAllocate = recursiveAllocate.bind(this);");
+  debuggee.eval("recursiveAllocate(200);");
+
+  // Now save a snapshot that will include the allocation stacks and read it
+  // back again.
+
+  const filePath = ChromeUtils.saveHeapSnapshot({ runtime: true });
+  ok(true, "Should be able to save a snapshot.");
+
+  const snapshot = ChromeUtils.readHeapSnapshot(filePath);
+  ok(snapshot, "Should be able to read a heap snapshot");
+  ok(HeapSnapshot.isInstance(snapshot), "Should be an instanceof HeapSnapshot");
+
+  const report = snapshot.takeCensus({
+    breakdown: {
+      by: "allocationStack",
+      then: { by: "count", bytes: true, count: true },
+      noStack: { by: "count", bytes: true, count: true },
+    },
+  });
+
+  // Keep this synchronized with `HeapSnapshot::MAX_STACK_DEPTH`!
+  const MAX_STACK_DEPTH = 60;
+
+  let foundStacks = false;
+  report.forEach((v, k) => {
+    if (k === "noStack") {
+      return;
+    }
+
+    foundStacks = true;
+    const depth = stackDepth(k);
+    dumpn("Stack depth is " + depth);
+    Assert.lessOrEqual(
+      depth,
+      MAX_STACK_DEPTH,
+      "Every stack should have depth less than or equal to the maximum stack depth"
+    );
+  });
+  ok(foundStacks);
+
+  do_test_finished();
+}