brew install --cask dotnet-sdk fails with Error: It seems the symlink source '/opt/homebrew/share/dotnet/dotnet' is not there.

[lgw4]

Output of brew config

HOMEBREW_VERSION: 3.6.20-97-g71fab93
ORIGIN: https://github.com/Homebrew/brew
HEAD: 71fab93983b47c73b3a36b24543a1adcea290044
Last commit: 68 minutes ago
Core tap ORIGIN: https://github.com/Homebrew/homebrew-core
Core tap HEAD: c27f57133838d853c5114fbce01dd678ba6db0e2
Core tap last commit: 2 hours ago
Core tap branch: master
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: ["--appdir=~/Applications"]
HOMEBREW_EDITOR: code
HOMEBREW_INSTALL_FROM_API: set
HOMEBREW_MAKE_JOBS: 10
Homebrew Ruby: 2.6.10 => /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby
CPU: 10-core 64-bit arm_firestorm_icestorm
Clang: 14.0.0 build 1400
Git: 2.39.1 => /opt/homebrew/bin/git
Curl: 7.86.0 => /usr/bin/curl
macOS: 13.2-arm64
CLT: 14.2.0.0.1.1668646533
Xcode: 14.2
Rosetta 2: false

Output of brew doctor

Your system is ready to brew.

Description of issue

When I attempt to install dotnet-sdk, installation fails with an error I have not seen before.

brew install --cask dotnet-sdk
==> Downloading https://download.visualstudio.microsoft.com/download/pr/dfbffbab-2187-44a8-b911-308136f001c1/8c754f776f6a476f6ab6681d72d88b2e/dotnet-sdk-7.0.102-osx-arm64.pkg
######################################################################## 100.0%
==> Installing Cask dotnet-sdk
==> Running installer for dotnet-sdk; your password may be necessary.
Package installers may write to any location; options such as `--appdir` are ignored.
installer: Package name is Microsoft .NET SDK 7.0.102 (arm64)
installer: Upgrading at base path /
installer: The upgrade was successful.
==> Purging files for version 7.0.102,dfbffbab-2187-44a8-b911-308136f001c1,8c754f776f6a476f6ab6681d72d88b2e of Cask dotnet-sdk
Error: It seems the symlink source '/opt/homebrew/share/dotnet/dotnet' is not there.

Has anyone else seen this, or am I doing something wrong?

Relevant casks

dotnet-sdk

[lucyllewy]

I'm seeing this too, on an m1 MacBook Air running macOS Ventura (13.1)

Brew Config:

HOMEBREW_VERSION: 3.6.20-167-g7a5f614
ORIGIN: https://github.com/Homebrew/brew
HEAD: 7a5f6143d3e7447a64255c548d2e51138c83acd3
Last commit: 9 hours ago
Core tap ORIGIN: https://github.com/Homebrew/homebrew-core
Core tap HEAD: 99230782ddeba4b5968910b776f67989d54177e9
Core tap last commit: 81 minutes ago
Core tap branch: master
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_DISPLAY: /private/tmp/com.apple.launchd.lgeZ15hyJI/org.xquartz:0
HOMEBREW_EDITOR: vim
HOMEBREW_INSTALL_FROM_API: set
HOMEBREW_MAKE_JOBS: 8
Homebrew Ruby: 2.6.10 => /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby
CPU: octa-core 64-bit arm_firestorm_icestorm
Clang: 14.0.0 build 1400
Git: 2.37.1 => /Applications/Xcode.app/Contents/Developer/usr/bin/git
Curl: 7.85.0 => /usr/bin/curl
macOS: 13.1-arm64
CLT: 14.2.0.0.1.1668646533
Xcode: 14.2
Rosetta 2: false

Brew Doctor:

Please note that these warnings are just used to help the Homebrew maintainers
with debugging if you file an issue. If everything you use Homebrew for is
working fine: please don't worry or file an issue; just ignore this. Thanks!

Warning: Unbrewed dylibs were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected dylibs:
  /usr/local/lib/libcrypto.1.1.dylib
  /usr/local/lib/libregina.dylib
  /usr/local/lib/libregutil.dylib
  /usr/local/lib/librxtest1.dylib
  /usr/local/lib/librxtest2.dylib
  /usr/local/lib/libykcs11.2.3.0.dylib
  /usr/local/lib/libykpiv.2.3.0.dylib

Warning: Unbrewed header files were found in /usr/local/include.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected header files:
  /usr/local/include/rexxsaa.h
  /usr/local/include/ykpiv/ykpiv-config.h
  /usr/local/include/ykpiv/ykpiv.h

Warning: Unbrewed '.pc' files were found in /usr/local/lib/pkgconfig.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected '.pc' files:
  /usr/local/lib/pkgconfig/ykcs11.pc
  /usr/local/lib/pkgconfig/ykpiv.pc

Warning: Unbrewed static libraries were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected static libraries:
  /usr/local/lib/libregina.a
  /usr/local/lib/libykcs11.a
  /usr/local/lib/libykpiv.a

Those libraries and headers reported by my run of brew doctor are unrelated to the issue AFAIK.

[gromgit]

This will sound bizarre, but just...

export HOMEBREW_NO_INSTALL_FROM_API=1 and run the brew install again.

[lucyllewy]

That did indeed get it installed. Could you explain what the environment variable there does and how it allowed home-brew to install dotnet-sdk correctly when it fails without the variable being set? That might be pertinent information for anyone googling similar issues to understand what the issue is and why this fixes it.

[gromgit]

Homebrew is beta-testing a major change in the default provisioning of formula/cask data, from "clone the rather large core repos" (which seems to cause grief for a surprising number folks) to "pull down a couple of much smaller JSON files from https://formulae.brew.sh/api" (hence "install from API"). This currently only affects folks who have developer mode turned out, i.e. whose HOMEBREW_VERSION reads like 3.6.20-167-g7a5f614 instead of just 3.6.20.

Setting HOMEBREW_NO_INSTALL_FROM_API tells Homebrew to keep using the original repos and code path, which are pretty well-tested.

The new default is HOMEBREW_INSTALL_FROM_API, and the new code surfaces weird side-effects that are currently being resolved as they arise.

For the gory details of your specific case: Homebrew/brew#13794 (comment)

[lucyllewy]

that's an interesting change, and is going to improve things immensely I would imagine. Thank you for the detailed explanation and hopefully this will help others understand the changes 💜 (Also, today I learned 😝)

[Rylan12]

This bug has now been fixed. You should no longer need to set HOMEBREW_NO_LONGER_INSTALL_FROM_API in order to install dotnet-sdk on M1.