1 files changed, 106 insertions, 0 deletions
diff --git a/devtools/server/tests/browser/browser_memory_allocations_01.js b/devtools/server/tests/browser/browser_memory_allocations_01.js
new file mode 100644
index 0000000000..d0bb53faa6
--- /dev/null
+++ b/devtools/server/tests/browser/browser_memory_allocations_01.js
@@ -0,0 +1,106 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+add_task(async function () {
+  const target = await addTabTarget("data:text/html;charset=utf-8,test-doc");
+  const memory = await target.getFront("memory");
+
+  await memory.attach();
+
+  await memory.startRecordingAllocations();
+  ok(true, "Can start recording allocations");
+
+  // Allocate some objects.
+  const [line1, line2, line3] = await SpecialPowers.spawn(
+    gBrowser.selectedBrowser,
+    [],
+    function () {
+      // Use eval to ensure allocating the object in the page's compartment
+      return content.eval(
+        "(" +
+          function () {
+            let alloc1, alloc2, alloc3;
+
+            /* eslint-disable max-nested-callbacks */
+            (function outer() {
+              (function middle() {
+                (function inner() {
+                  alloc1 = {};
+                  alloc1.line = Error().lineNumber;
+                  alloc2 = [];
+                  alloc2.line = Error().lineNumber;
+                  // eslint-disable-next-line new-parens
+                  alloc3 = new (function () {})();
+                  alloc3.line = Error().lineNumber;
+                })();
+              })();
+            })();
+            /* eslint-enable max-nested-callbacks */
+
+            return [alloc1.line, alloc2.line, alloc3.line];
+          } +
+          ")()"
+      );
+    }
+  );
+
+  const response = await memory.getAllocations();
+
+  await memory.stopRecordingAllocations();
+  ok(true, "Can stop recording allocations");
+
+  // Filter out allocations by library and test code, and get only the
+  // allocations that occurred in our test case above.
+
+  function isTestAllocation(alloc) {
+    const frame = response.frames[alloc];
+    return (
+      frame &&
+      frame.functionDisplayName === "inner" &&
+      (frame.line === line1 || frame.line === line2 || frame.line === line3)
+    );
+  }
+
+  const testAllocations = response.allocations.filter(isTestAllocation);
+  ok(
+    testAllocations.length >= 3,
+    "Should find our 3 test allocations (plus some allocations for the error " +
+      "objects used to get line numbers)"
+  );
+
+  // For each of the test case's allocations, ensure that the parent frame
+  // indices are correct. Also test that we did get an allocation at each
+  // line we expected (rather than a bunch on the first line and none on the
+  // others, etc).
+
+  const expectedLines = new Set([line1, line2, line3]);
+  is(expectedLines.size, 3, "We are expecting 3 allocations");
+
+  for (const alloc of testAllocations) {
+    const innerFrame = response.frames[alloc];
+    ok(innerFrame, "Should get the inner frame");
+    is(innerFrame.functionDisplayName, "inner");
+    expectedLines.delete(innerFrame.line);
+
+    const middleFrame = response.frames[innerFrame.parent];
+    ok(middleFrame, "Should get the middle frame");
+    is(middleFrame.functionDisplayName, "middle");
+
+    const outerFrame = response.frames[middleFrame.parent];
+    ok(outerFrame, "Should get the outer frame");
+    is(outerFrame.functionDisplayName, "outer");
+
+    // Not going to test the rest of the frames because they are Task.jsm
+    // and promise frames and it gets gross. Plus, I wouldn't want this test
+    // to start failing if they changed their implementations in a way that
+    // added or removed stack frames here.
+  }
+
+  is(expectedLines.size, 0, "Should have found all the expected lines");
+
+  await memory.detach();
+
+  await target.destroy();
+});