macOS Tahoe 26 support

[milksense]

brew doctor output

/opt/homebrew/Library/Homebrew/macos_version.rb:53:in 'MacOSVersion#initialize': unknown or unsupported macOS version: "26.0" (MacOSVersion::Error)
	from /opt/homebrew/Library/Homebrew/os/mac.rb:44:in 'Class#new'
	from /opt/homebrew/Library/Homebrew/os/mac.rb:44:in 'OS::Mac.full_version'
	from /opt/homebrew/Library/Homebrew/os/mac.rb:32:in 'OS::Mac.version'
	from /opt/homebrew/Library/Homebrew/os.rb:60:in '<module:OS>'
	from /opt/homebrew/Library/Homebrew/os.rb:7:in '<main>'
	from <internal:/opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.4/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:37:in 'Kernel#require'
	from <internal:/opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.4/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:37:in 'Kernel#require'
	from /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.4/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in 'Kernel#require'
	from /opt/homebrew/Library/Homebrew/global.rb:138:in '<top (required)>'
	from /opt/homebrew/Library/Homebrew/brew.rb:18:in 'Kernel#require_relative'
	from /opt/homebrew/Library/Homebrew/brew.rb:18:in '<main>'

Verification

• My "brew doctor output" above says Your system is ready to brew. and am still able to reproduce my issue.
• I ran brew update twice and am still able to reproduce my issue.
• This issue's title and/or description do not reference a single formula e.g. brew install wget. If they do, open an issue at https://github.com/Homebrew/homebrew-core/issues/new/choose instead.

brew config output

/opt/homebrew/Library/Homebrew/macos_version.rb:53:in 'MacOSVersion#initialize': unknown or unsupported macOS version: "26.0" (MacOSVersion::Error)
	from /opt/homebrew/Library/Homebrew/os/mac.rb:44:in 'Class#new'
	from /opt/homebrew/Library/Homebrew/os/mac.rb:44:in 'OS::Mac.full_version'
	from /opt/homebrew/Library/Homebrew/os/mac.rb:32:in 'OS::Mac.version'
	from /opt/homebrew/Library/Homebrew/os.rb:60:in '<module:OS>'
	from /opt/homebrew/Library/Homebrew/os.rb:7:in '<main>'
	from <internal:/opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.4/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:37:in 'Kernel#require'
	from <internal:/opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.4/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:37:in 'Kernel#require'
	from /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.4/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in 'Kernel#require'
	from /opt/homebrew/Library/Homebrew/global.rb:138:in '<top (required)>'
	from /opt/homebrew/Library/Homebrew/brew.rb:18:in 'Kernel#require_relative'
	from /opt/homebrew/Library/Homebrew/brew.rb:18:in '<main>'

What were you trying to do (and why)?

brew *

What happened (include all command output)?

'MacOSVersion#initialize': unknown or unsupported macOS version: "26.0" (MacOSVersion::Error)

What did you expect to happen?

Successful execution :)

Step-by-step reproduction instructions (by running brew commands)

brew *

Exclude brew update

OS version

Version 26.0 Beta (25A5279m)

[falchion10]

Same issue, I'm assuming it'll be fixed within the next day or so.

[tbiehn]

… removed previous comments because people are using the code - sorry about that …

And of course all the backend stuff the devs are probably busy on.

[Bo98]

It's being worked on: #20062. It's more involved than a 1 line change but it's mostly ready pending final testing I'm currently doing.

[codingMustache]

Other people coming on here reading this the 1st change is on line 21 and the 2nd on line 51
of /opt/homebrew/Library/Homebrew/macos_version.rb

[RobotLeopard86]

I made two changes to that file and it worked. Just added a tahoe key and edited a regex. I'll just use that until whatever release merges the Tahoe patch officially.

[Bo98]

Please use brew update to update to 4.5.6 rather than editing. Autoupdate might take 24 hours but brew update should apply immediately.

If you've already edited: updating might break your install if it detects a conflict (as the above regex was incorrect and we applied a different one). Resetting your repository should fix that.

[Panajev]

I think this issue should be re-opened or updated @Bo98 . I ran brew update and I got the initial macOS 26 update, but it was still giving me the same error about unknown or unsupported macOS version.

Using the regex that was shared earlier in this thread:

    raise MacOSVersion::Error, version unless /\A{1,2}\d+(?:\.\d+){0,2}\Z/.match?(version)
    # raise MacOSVersion::Error, version unless /\A\d{2,}(?:\.\d+){0,2}\z/.match?(version)

This is the only change I did and the error stopped on macOS, but weirdly enough it does not comes back if I comment the first line and uncomment the other... :/...

[Bo98]

Works fine for me in a macOS 26 VM. Something I've seen happen is brew update might fail to update but it's not obvious because the "unknown macOS" error is bigger (e.g. see #20085). Not really much we can do about that now but we can perhaps look at making update errors more obvious going forward.

Sounds like it did eventually update for you just before you tried to edit. The regex with \d{2,} is the fixed regex.

[Panajev]

Works fine for me in a macOS 26 VM. Something I've seen happen is brew update might fail to update but it's not obvious because the "unknown macOS" error is bigger (e.g. see #20085). Not really much we can do about that now but we can perhaps look at making update errors more obvious going forward.

Sounds like it did eventually update for you just before you tried to edit. The regex with \d{2,} is the fixed regex.

Yep it did update. I think it would help if I actually explained the steps I did as follows:

• brew update (actually more than once without seeing an error beside something about getting the user in GitHub.com… :))
• checked the .rb in Homebrew file and it had all the changes referenced in the PR with the fix / initial Tahoe support
• Tried to upgrade brews (using brew bundle and custom Brewfile)
• Got the error again
• Tried to make the change to the .rb file people were suggesting in the other issues (including the version number being defined 26.0 instead of 26 but it made the situation worse)
• Tried to upgrade brews Got errors
• Undid the changes and did only the change for the regex in the .rb file
• Tried to upgrade brews, did not get an error
• Undid all changes in the .rb file and upgraded brews without an issue (which left me confused)

Thank you for your help with this, trying to understand this better.