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<!--
Bug 1068144 - Test getting the timestamps for allocations.
-->
<head>
  <meta charset="utf-8">
  <title>Memory monitoring actor test</title>
  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css">
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<body>
<pre id="test">
<script src="memory-helpers.js" type="application/javascript"></script>
<script>
"use strict";

window.onload = function() {
  SimpleTest.waitForExplicitFinish();

  (async function() {
    const { memory, target } = await startServerAndGetSelectedTabMemory();
    await memory.attach();

    const allocs = [];
    function allocator() {
      allocs.push({});
    }

    // Using setTimeout results in wildly varying delays that make it hard to
    // test our timestamps and results in intermittent failures. Instead, we
    // actually spin an empty loop for a whole millisecond.
    function actuallyWaitOneWholeMillisecond() {
      const start = window.performance.now();
      // eslint-disable-next-line curly
      while (window.performance.now() - start < 1.000);
    }

    await memory.startRecordingAllocations();

    allocator();
    actuallyWaitOneWholeMillisecond();
    allocator();
    actuallyWaitOneWholeMillisecond();
    allocator();

    const response = await memory.getAllocations();
    await memory.stopRecordingAllocations();

    ok(response.allocationsTimestamps, "The response should have timestamps.");
    is(response.allocationsTimestamps.length, response.allocations.length,
       "There should be a timestamp for every allocation.");

    const allocatorIndices = response.allocations
      .map(function(a, idx) {
        const frame = response.frames[a];
        if (frame && frame.functionDisplayName === "allocator") {
          return idx;
        }
        return null;
      })
      .filter(function(idx) {
        return idx !== null;
      });

    is(allocatorIndices.length, 3,
       "Should have our 3 allocations from the `allocator` timeouts.");

    let lastTimestamp;
    for (let i = 0; i < 3; i++) {
      const timestamp = response.allocationsTimestamps[allocatorIndices[i]];
      info("timestamp", timestamp);
      ok(timestamp, "We should have a timestamp for the `allocator` allocation.");

      if (lastTimestamp) {
        const delta = timestamp - lastTimestamp;
        info("delta since last timestamp", delta);
        // ms
        ok(delta >= 1,
           "The timestamp should be about 1 ms after the last timestamp.");
      }

      lastTimestamp = timestamp;
    }

    await memory.detach();
    destroyServerAndFinish(target);
  })();
};
</script>
</pre>
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