How to symlink/install FluxEngine.app to /Applications?

[jedahan]

Output of brew config

HOMEBREW_VERSION: 4.4.19-35-gc757219
ORIGIN: https://github.com/Homebrew/brew
HEAD: c7572194efe046549fd253cfff33fdc45af59fce
Last commit: 4 hours ago
Branch: master
Core tap JSON: 30 Jan 15:23 UTC
Core cask tap HEAD: 207507d6803bce403fa05fe0e483536d73a1c53f
Core cask tap last commit: 19 hours ago
Core cask tap JSON: 30 Jan 15:23 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_EDITOR: hx
HOMEBREW_MAKE_JOBS: 16
HOMEBREW_NO_ENV_HINTS: set
HOMEBREW_SORBET_RUNTIME: set
Homebrew Ruby: 3.3.7 => /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.3.7/bin/ruby
CPU: 16-core 64-bit arm_brava
Clang: 16.0.0 build 1600
Git: 2.39.5 => /Library/Developer/CommandLineTools/usr/bin/git
Curl: 8.7.1 => /usr/bin/curl
macOS: 15.1.1-arm64
CLT: 16.2.0.0.1.1733547573
Xcode: N/A
Rosetta 2: false

Output of brew doctor

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Warning: No Cask quarantine support available: unknown reason.

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/libCAPSImage.dylib

Warning: Some taps are not on the default git origin branch and may not receive
updates. If this is a surprise to you, check out the default branch with:
  git -C $(brew --repo jedahan/digipres) checkout master

Description of issue

I am wondering how to install a .app to the correct location that has been built locally. I've tried including the app stanza, but that is cask-only, and I cannot find any examples of casks that build from source / head-only.

fluxengine-gui.rb

class FluxengineGui < Formula
  version "2024-11-24"
  desc "PSOC5 floppy disk imaging interface"
  homepage "https://github.com/davidgiven/fluxengine"
  license "MIT"

  url "https://github.com/davidgiven/fluxengine.git", revision: "9ce405cec50ded5f64774d2448d9438a7e20b713"

  # dependencies from https://github.com/davidgiven/fluxengine/blob/master/.github/workflows/release.yml
  depends_on "sqlite3"
  depends_on "pkg-config" => :build
  depends_on "libusb"
  depends_on "protobuf"
  depends_on "wxwidgets"
  depends_on "fmt"
  depends_on "make" => :build
  depends_on "coreutils" => :build
  depends_on "dylibbundler"
  depends_on "libjpeg"

  # Necessary to build just the .app file without building a pkg file
  patch do
    url "https://github.com/davidgiven/fluxengine/pull/800/commits/d4c1dfee59045a062658c4b1070d77a660d2d378.patch?full_index=1"
    sha256 "a9bb2ee4afbba1bba81ffdb803c50bbcc50b3344986f9fd81c96b8802f96f126"
  end

  def install
    # the build shells out to brew to copy licenses over, we replicate that here
    system "sed", "-i", "-E", "/.*brew --prefix.*/d", "src/gui/build.py"
    system "gmake", "FluxEngine.app"

    # copy the licenses
    cp "#{Formula["wxwidgets"].opt_prefix}/README.md", "FluxEngine.app/Contents/libs/wxWidgets.md"
    cp "#{Formula["protobuf"].opt_prefix}/LICENSE", "FluxEngine.app/Contents/libs/protobuf.md"
    cp "#{Formula["fmt"].opt_prefix}/LICENSE", "FluxEngine.app/Contents/libs/fmt.md"
    cp "#{Formula["libpng"].opt_prefix}/LICENSE", "FluxEngine.app/Contents/libs/libpng.md"
    cp "#{Formula["libjpeg"].opt_prefix}/README", "FluxEngine.app/Contents/libs/libjpeg.md"
    cp "#{Formula["abseil"].opt_prefix}/LICENSE", "FluxEngine.app/Contents/libs/abseil.md"
    cp "#{Formula["libtiff"].opt_prefix}/LICENSE.md", "FluxEngine.app/Contents/libs/libtiff.md"
    cp "#{Formula["zstd"].opt_prefix}/LICENSE", "FluxEngine.app/Contents/libs/zstd.md"

    prefix.install "FluxEngine.app"
  end
end

So the app is in /opt/homebrew/Cellar/fluxengine-gui/2024-11-24/FluxEngine.app , but what should I do to get it into /Applications?

[jedahan]

Pull request I am working on is viewable here mistydemeo/homebrew-digipres#21

[SMillerDev]

So the app is in /opt/homebrew/Cellar/fluxengine-gui/2024-11-24/FluxEngine.app , but what should I do to get it into /Applications?

You can't, formulae can't install outside the Homebrew prefix (/opt/homebrew in your case). For that you'd need to have a pre-built binary and install it as a cask.

[jedahan]

I'm a little confused because I have another .app that was installed via homebrew, built using cmake + ninja, and is symlinked in /Applications/ (GammaRay). So it seems there is a place I am not correctly installing the .app to in the build sandbox that would achieve the same thing.

[jedahan]

Put another way, is there a way I can indicate what should be symlinked with brew link fluxengine-gui, even if it requires a manual user step?

[SMillerDev]

As far as I know, that hasn't been possible since 2018 or so.

[jedahan]

Would you suggest me opening a new discussion that is more about 'How can a Formula that builds an .app locally be installed correctly through homebrew?' or just retitle this one?

[jedahan]

So would you recommend adding a caveats section and telling the user to manually symlink or copy it over? Or is there a better way to support building an .app or .pkg locally and installing that?