From fc3c71aee792510e14f546b54fbe035d54747dae Mon Sep 17 00:00:00 2001
From: Michael Cho <cho-m@tuta.io>
Date: Fri, 30 Sep 2022 16:45:26 -0700
Subject: [PATCH] nu: fix build on Apple Silicon

---
 Formula/nu.rb | 37 ++++++++++++++++++++++++++++++++-----
 1 file changed, 32 insertions(+), 5 deletions(-)

diff --git a/Formula/nu.rb b/Formula/nu.rb
index f188c297a19a2..55071cdc72ed1 100644
--- a/Formula/nu.rb
+++ b/Formula/nu.rb
@@ -5,6 +5,7 @@ class Nu < Formula
   sha256 "1a6839c1f45aff10797dd4ce5498edaf2f04c415b3c28cd06a7e0697d6133342"
   license "Apache-2.0"
   revision 1
+  head "https://github.com/programming-nu/nu.git", branch: "master"
 
   bottle do
     sha256 cellar: :any,                 monterey:     "a2a1bdb6473b6afd30cde5def27158415fb38f92851b8a252498631f7e2f350d"
@@ -15,7 +16,7 @@ class Nu < Formula
 
   depends_on "pcre"
 
-  uses_from_macos "llvm" => [:build, :test]
+  uses_from_macos "llvm" => :build
   uses_from_macos "swift" => :build # For libdispatch on Linux.
   uses_from_macos "libffi"
 
@@ -23,16 +24,37 @@ class Nu < Formula
     depends_on "gnustep-make" => :build
     depends_on "gnustep-base"
     depends_on "libobjc2"
+    depends_on "readline"
+  end
+
+  on_arm do
+    # objc/NuBridge.m:1242:6: error: implicit declaration of function 'ffi_prep_closure' is invalid in C99
+    # Since libffi.tbd only exports '_ffi_prep_closure' on x86_64, we need to use formula until fixed.
+    # Issue ref: https://github.com/programming-nu/nu/issues/97
+    depends_on "libffi"
   end
 
   # Clang must be used on Linux because GCC Objective-C support is insufficient.
   fails_with :gcc
 
+  # Fix Snow Leopard or Lion check to avoid `-arch x86_64` being added to ARM build
+  # PR ref: https://github.com/programming-nu/nu/pull/101
+  # TODO: Remove if upstream PR is merged and in a release.
+  patch do
+    url "https://github.com/programming-nu/nu/commit/0a837a407f9e9b8f7861b0dd2736f54c04729642.patch?full_index=1"
+    sha256 "6c8567f0c2681f652dc087f6ef4b713bcc598e99729099a910984f9134f6a72c"
+  end
+
   def install
     ENV.delete("SDKROOT") if MacOS.version < :sierra
     ENV["PREFIX"] = prefix
     # Don't hard code path to clang.
     inreplace "tools/nuke", "/usr/bin/clang", ENV.cc
+    # Work around ARM build error where directives removed necessary code and broke mininush.
+    # Nu uncaught exception: NuIvarAddedTooLate: explicit instance variables ...
+    # Issue ref: https://github.com/programming-nu/nu/issues/102
+    inreplace "objc/NuOperators.m", "#if defined(__x86_64__) || TARGET_OS_IPHONE",
+                                    "#if defined(__x86_64__) || defined(__arm64__)"
 
     unless OS.mac?
       ENV.append_path "PATH", Formula["gnustep-make"].libexec
@@ -45,9 +67,6 @@ def install
       ]
       ENV["LIBDIRS"] = ldflags.join(" ")
 
-      # Remove unused prefix from ffi.h
-      inreplace ["objc/NuBridge.h", "objc/NuBridge.m", "objc/Nu.m"], "x86_64-linux-gnu/", ""
-
       # Remove CFLAGS that force using GNU runtime on Linux.
       # Remove this workaround when upstream drops these flags or provides a way to disable them.
       # Reported upstream here: https://github.com/programming-nu/nu/issues/99.
@@ -63,7 +82,15 @@ def install
         (set @framework_install_path "#{frameworks}")
       EOS
     end
-    system "make"
+
+    # Remove bundled libffi
+    (buildpath/"libffi").rmtree
+
+    # Remove unused prefix from ffi.h to match directory structure of libffi formula
+    include_path = (OS.mac? && Hardware::CPU.arm?) ? "ffi" : "x86_64-linux-gnu"
+    inreplace ["objc/NuBridge.h", "objc/NuBridge.m", "objc/Nu.m"], "<#{include_path}/", "<"
+
+    system "make", "CC=#{ENV.cc}"
     system "./mininush", "tools/nuke"
     bin.mkdir
     lib.mkdir