OS::Mac::Version: add Big Sur

[mistydemeo]

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• Have you successfully run brew tests with your changes locally?

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[vinkla]

There are multiple reports that macOS Big Sur is a major bump:

• https://twitter.com/stroughtonsmith/status/1275150531154108417
• https://twitter.com/thecomputerclan/status/1275135276298493952
• https://twitter.com/search?q=macOS%2011&src=typed_query

[Bo98]

There seems to be an inconsistency, with some references to 10.16 in the installers.

We will go by whatever /usr/bin/sw_vers -productVersion returns, if someone is able to check that.

[claui]

More evidence:

https://developer.apple.com/design/human-interface-guidelines/macos/overview/whats-new-in-macos/

[Bo98]

Our analytics show over 2,000 instances of 10.16 in the last 30 days, and there is still a large number of reports of the OS internally calling itself 10.16 (see: installer, Xcode Intel-only builds, MACOSX_DEPLOYMENT_TARGET refusing 11.0, etc). We will go by sw_vers so if someone shows it returns 11.0 then we'll change it here.

[Bo98]

Ok just checked up on this.

I'm told that for Intel this change is correct and sw_vers reports 10.16, but for Apple Silicon it reports 11.0. I suppose we can make this a conditional on Hardware::CPU.intel?/Hardware::CPU.arm?.

[mistydemeo]

I expect that we will see this unify with time, but we're still in very early days for this release. We'll continue to update our code as we see the OS solidify.

[Geekiac]

The output from sw_vers on my MacBookPro gives:

ProductName: macOS
ProductVersion: 11.0.1
BuildVersion: 20B29