jit/backend/x86/test/test_jitlog.py::TestJitlog::()::test_env

self = <rpython.jit.backend.x86.test.test_jitlog.TestJitlog instance at 0x00007ff140447160>
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x00007ff1524cb1a0>
tmpdir = local('/private/tmp/buildbot-x86_64/pytest/pytest-of-matti/pytest-950/test_env0')

    def test_env(self, monkeypatch, tmpdir):
        file = tmpdir.join('jitlog')
        monkeypatch.setenv(rjitlog.test_jitlog_name, file.strpath)
        f = self.run_sample_loop(None)
        self.meta_interp(f, [10, 0])
        assert os.path.exists(file.strpath)
        with file.open('rb') as fd:
            # check the file header
>           assert fd.read(3) == jl.MARK_JITLOG_HEADER + jl.JITLOG_VERSION_16BIT_LE
E           AssertionError: assert '' == '\x1e\x04\x00'
E             + \x1e\x04\x00

jit/backend/test/jitlog_test.py:39: AssertionError

builder: rpython-macos-x86-64 build #278+

test: jit/backend/x86/test/test_jitlog.py::TestJitlog::()::test_env