pip-compile 1.10+ not finding tornado dependencies

[haylo75]

Using pip-compile 1.9.0 with a requirement of tornado==4.5.2, the required dependencies are found and generated. Starting with 1.10.0, said dependencies are no longer found. Verbose output from 1.9.0 indicates 3 rounds of dependency checks, but zero rounds with 1.10.0

I checked the setup.py for Tornado, and here is the relevant section.

if setuptools is not None:
    # If setuptools is not available, you're on your own for dependencies.
    install_requires = []
    if sys.version_info < (2, 7):
        # Only needed indirectly, for singledispatch.
        install_requires.append('ordereddict')
    if sys.version_info < (2, 7, 9):
        install_requires.append('backports.ssl_match_hostname')
    if sys.version_info < (3, 4):
        install_requires.append('singledispatch')
        # Certifi is also optional on 2.7.9+, although making our dependencies
        # conditional on micro version numbers seems like a bad idea
        # until we have more declarative metadata.
        install_requires.append('certifi')
    if sys.version_info < (3, 5):
        install_requires.append('backports_abc>=0.4')
    kwargs['install_requires'] = install_requires

Environment Versions

1. Mac OS X 10.11.6
2. Python version: 2.7.10
3. pip version: 9.1.0
4. pip-tools version: 1.10.0 (and 1.10.1)

Steps to replicate

1. Write a requirements.txt file with the following contents:

echo tornado==4.5.2 > requirements.in

2. Run pip-compile in verbose mode

pip-compile requirements.in -v -r

3. View output

Expected result

See attached pip-requirements-1.9.0.txt
pip-requirements-1.9.0.txt

Actual result

See attached pip-requirements-1.10.0.txt
pip-requirements-1.10.0.txt

[vphilippon]

This is a known issue fixed in master, and will be part of 1.10.2, when a release will be available (see #531 as of why a bugfix is not out yet).

[haylo75]

Thanks for the context. I checked out master and tornado 4.5.2 and its dependencies compiled just fine. I'll close this issue since it was already addressed.