Doesn't yet implement the rules in the docs, but I think the doc rules
could maybe change to match this. Needs lots of cleanup work and
thorough testing, but this is a great start.
* Don't implement the rules for when preloading occurs yet
* Don't attempt to streamily preload modules downstream while this
context hasn't yet received the final module. There is quite
significant latency buried in here, but for now it's a lot of work to
fix.
This works well enough to handle at least the mitogen package, but it's
likely broken for anything bigger.
It seems gevent automatically sets blocking behaviour on fds produced by
the socket module, which causes the Python process we fork to fail
horribly. So in the child, always reset the blocking flag.
e.g. assert x == y -> self.assertEqual(x, y);
self.assertTrue(isinstance(x, y)) -> self.assertIsInstance(x, y)
These specific methods give more useful errors in the case of a test
failure.
Although these are synonyms in Python 2.x, when using MyPy to typecheck
code use of file() causes spurious errors.
This commit also serves as one small step to Python 3.x compatibility,
since 3.x removes the file() builtin.
We use test.sh to consolidate test cases in one file so the README
would not be outdated easier rather than the hard-coded test commands
in a code block.
On my laptop (Ubuntu 17.10, Python 2.7.14 in a virtualenv),
`test_regular_mod` fails with
```
AssertionError: "\nimport sys\n\n\ndef say_hi():\n print 'hi'\n" !=
'\x03\xf3\r\n\xbbW\xd5Yc\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00@\x00\x00\x00s\x19\x00\x00\x00d\x00\x00d\x01\x00l\x00\x00Z\x00\x00d\x02\x00\x84\x00\x00Z\x01\x00d\x01\x00S(\x03\x00\x00\x00i\xff\xff\xff\xffNc\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00C\x00\x00\x00s\t\x00\x00\x00d\x01\x00GHd\x00\x00S(\x02\x00\x00\x00Nt\x02\x00\x00\x00hi(\x00\x00\x00\x00(\x00\x00\x00\x00(\x00\x00\x00\x00(\x00\x00\x00\x00sF\x00\x00\x00/home/alex/src/mitogen/tests/data/module_finder_testmod/regular_mod.pyt\x06\x00\x00\x00say_hi\x05\x00\x00\x00s\x02\x00\x00\x00\x00\x01(\x02\x00\x00\x00t\x03\x00\x00\x00sysR\x01\x00\x00\x00(\x00\x00\x00\x00(\x00\x00\x00\x00(\x00\x00\x00\x00sF\x00\x00\x00/home/alex/src/mitogen/tests/data/module_finder_testmod/regular_mod.pyt\x08\x00\x00\x00<module>\x02\x00\x00\x00s\x02\x00\x00\x00\x0c\x03'
```
`__file__` contains the path of the compiled `.pyc`, not the `.py`
source file.
Since the above if block ends in a call to os.execv() this block will
only ever run when the if condition was false. Hence putting it in an
else clause is unnecessary.
Ubuntu 17.04 provides Docker 1.12.6, which has API version 1.24.
`dev_requirements.txt` specifies the docker-py 2.5.1, which by default
requests API version 1.30.
Hence when the SSH unit tests try to run the container specified in
`DockerizedSshDaemon` an error occurs
```
APIError: 400 Client Error: Bad Request ("client is newer than server
(client API version: 1.30, server API version: 1.24)")
```