Visual Studio 2017 support

[jaraco]

Visual Studio 2017 doesn't set the same registry entries it used to, which means any code to detect it has to change significantly.

Part of the install changes to VS allow multiple instances to be installed simultaneously, so it no longer made sense to have a single key to the install path. It's also far more likely for users to have made changes to optional components, and so essential pieces could be missing.

There is a new COM API available for detecting various VS installs. Unfortunately, it's a bit unwieldy from pure Python code, but zooba has thrown together a small wrapper to pull out the most important information. Alternatively, look at the source code to see how to copy it.

[JGoutin]

#995 add at least the support for "Microsoft Visual Studio Build Tools 2017". I thinks, this should also work with Visual Studio 2017. I'll look at this with the community edition.

I see also Windows 10 SDK can be installed with multiple versions. I am not sure the current code always use the last. I'll look at this also.

I don't think we really need to use the COM API. The actual pure python way work good for the build tools and can be expended to the full VS2017.

[dashesy]

does this fix appear in setuptools 41.0.1?

[jaraco]

The commits were first included in 34.4.1. I don't know if there were rolled back since then, but if they were, they didn't link to this issue or the PR, so I believe they should appear there.

[dashesy]

I have both 2015 and 2017 installed (need for different projects) and setuptools always picks 2015 even when I am in VS2017 development command prompt.

In [1]: from setuptools import msvc

In [2]: si = msvc.SystemInfo(msvc.RegistryInfo(msvc.PlatformInfo('amd64')))

In [3]: si.find_available_vc_vers()
Out[3]: [10.0, 14.0, 15.0]
In [4]: si.vc_ver
Out[4]: 15.0

In [5]: si.VCInstallDir
Out[5]: 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Enterprise\\VC\\Tools\\MSVC\\14.16.27023'

This is the cl that is selected: 'C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\VC\\BIN\\x86_amd64\\cl.exe' even though

This is the correct cl: C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\VC\Tools\MSVC\14.16.27023\bin\Hostx64\x64\cl.exe or C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\bin\Hostx64\x64\cl.exe

Will look at debugging this further today

Ok, I had to set DISTUTILS_USE_SDK = 1 beforehand, otherwise _get_vc_env was finding the incorrect vcvars.bat and by running it changing the path, so incorrect cl.exe was found! all even though correct cl.exe was already in the path (running in the VS2017 commandline).
I will dig deeper to see if there is anything else, but it seems like _get_vc_env also should be patched for VS2017+.