def METHOD_NAME(self) -> None:
    root = self.mkdtemp()
    expect_hex = self.write_file_and_hash(os.path.join(root, "foo"), "hello\n")
    with open(os.path.join(root, ".watchmanconfig"), "w") as f:
        f.write(json.dumps({"content_hash_warming": True}))
    self.watchmanCommand("watch", root)
    self.assertFileList(root, [".watchmanconfig", "foo"])
    def cachePopulate():
        stats = self.watchmanCommand("debug-contenthash", root)
        return stats["size"] >= 2 and stats["cacheStore"] >= 2
    self.waitFor(cachePopulate)
    stats = self.watchmanCommand("debug-contenthash", root)
    size = stats["size"]
    self.assertEqual(size, 2)
    self.assertEqual(stats["cacheHit"], 0)
    self.assertEqual(stats["cacheMiss"], size)
    self.assertEqual(stats["cacheStore"], size)
    self.assertEqual(stats["cacheLoad"], size)
    res = self.watchmanCommand(
        "query",
        root,
        {"expression": ["name", "foo"], "fields": ["name", "content.sha1hex"]},
    )
    self.assertEqual(expect_hex, res["files"][0]["content.sha1hex"])