brew.sh: set HOMEBREW_FORCE_HOMEBREW_CORE_REPO_ON_LINUX when core repo is homebrew-core

See https://github.com/Homebrew/install/pull/571

When the install script sets as https://github.com/Homebrew/homebrew-core,
we need to use the homebrew-core bottle domain, and correctly set
the HOMEBREW_CORE_DEFAULT_GIT_REMOTE below.

This also fixes the brew doctor issue for new homebrew-core Linux installations

Warning: Suspicious https://github.com/Homebrew/linuxbrew-core git origin remote found.
The current git origin is:
  https://github.com/Homebrew/homebrew-core

With a non-standard origin, Homebrew won't update properly.
You can solve this by setting the origin remote:
  git -C "/home/linuxbrew/.linuxbrew/Homebrew/Library/Taps/homebrew/homebrew-core" remote set-url origin https://github.com/Homebrew/linuxbrew-core

Library/Homebrew/api/versions.rb

@@ -27,7 +27,9 @@ module Homebrew
 
         sig { params(name: String).returns(T.nilable(PkgVersion)) }
         def latest_formula_version(name)
-          versions = if OS.mac? || Homebrew::EnvConfig.force_homebrew_on_linux?
+          versions = if OS.mac? ||
+                        Homebrew::EnvConfig.force_homebrew_on_linux? ||
+                        Homebrew::EnvConfig.force_homebrew_core_repo_on_linux?
             formulae
           else
             linux

Library/Homebrew/brew.sh

@@ -469,6 +469,17 @@ Your Git executable: $(unset git && type -p ${HOMEBREW_GIT})"
 
   HOMEBREW_LINUX_MINIMUM_GLIBC_VERSION="2.13"
   unset HOMEBREW_MACOS_SYSTEM_RUBY_NEW_ENOUGH
+
+  HOMEBREW_CORE_REPOSITORY_ORIGIN="$("${HOMEBREW_GIT}" -C "${HOMEBREW_CORE_REPOSITORY}" remote get-url origin)"
+  if [[ "${HOMEBREW_CORE_REPOSITORY_ORIGIN}" = "https://github.com/Homebrew/homebrew-core" ]]
+  then
+    # If the remote origin has been set to Homebrew/homebrew-core by the install script,
+    # then we are in the case of a new installation of brew, using Homebrew/homebrew-core as a Linux core repository.
+    # In that case, set HOMEBREW_FORCE_HOMEBREW_CORE_REPO_ON_LINUX=1 to set the right HOMEBREW_BOTTLE_DOMAIN below.
+    # TODO: Once the linuxbrew-core migration is done we will be able to clean this up and
+    # remove HOMEBREW_FORCE_HOMEBREW_CORE_REPO_ON_LINUX
+    export HOMEBREW_FORCE_HOMEBREW_CORE_REPO_ON_LINUX="1"
+  fi
 fi
 
 # A bug in the auto-update process prior to 3.1.2 means $HOMEBREW_BOTTLE_DOMAIN
@@ -484,7 +495,7 @@ then
   unset HOMEBREW_BOTTLE_DOMAIN
 fi
 
-if [[ -n "${HOMEBREW_MACOS}" || -n "${HOMEBREW_FORCE_HOMEBREW_ON_LINUX}" ]]
+if [[ -n "${HOMEBREW_MACOS}" || -n "${HOMEBREW_FORCE_HOMEBREW_ON_LINUX}" || -n "${HOMEBREW_FORCE_HOMEBREW_CORE_REPO_ON_LINUX}" ]]
 then
   HOMEBREW_BOTTLE_DEFAULT_DOMAIN="https://ghcr.io/v2/homebrew/core"
 else
@@ -624,7 +635,7 @@ then
 fi
 export HOMEBREW_BREW_GIT_REMOTE
 
-if [[ -n "${HOMEBREW_MACOS}" ]] || [[ -n "${HOMEBREW_FORCE_HOMEBREW_ON_LINUX}" ]]
+if [[ -n "${HOMEBREW_MACOS}" ]] || [[ -n "${HOMEBREW_FORCE_HOMEBREW_ON_LINUX}" ]]  || [[ -n "${HOMEBREW_FORCE_HOMEBREW_CORE_REPO_ON_LINUX}" ]]
 then
   HOMEBREW_CORE_DEFAULT_GIT_REMOTE="https://github.com/Homebrew/homebrew-core"
 else

Library/Homebrew/env_config.rb

@@ -277,6 +277,10 @@ module Homebrew
                      "when auditing macOS formulae while on Linux. Implies `HOMEBREW_FORCE_HOMEBREW_ON_LINUX`.",
         boolean:     true,
       },
+      HOMEBREW_FORCE_HOMEBREW_CORE_REPO_ON_LINUX: {
+        description: "If set, running Homebrew on Linux will use homebrew-core instead of linuxbrew-core.",
+        boolean:     true,
+      },
       HOMEBREW_SKIP_OR_LATER_BOTTLES:             {
         description: "If set along with `HOMEBREW_DEVELOPER`, do not use bottles from older versions " \
                      "of macOS. This is useful in development on new macOS versions.",

Library/Homebrew/extend/os/linux/api/analytics.rb

@@ -6,7 +6,9 @@ module Homebrew
     module Analytics
       class << self
         def analytics_api_path
-          return generic_analytics_api_path if Homebrew::EnvConfig.force_homebrew_on_linux?
+          return generic_analytics_api_path if
+            Homebrew::EnvConfig.force_homebrew_on_linux? ||
+            Homebrew::EnvConfig.force_homebrew_core_repo_on_linux?
 
           "analytics-linux"
         end

Library/Homebrew/extend/os/linux/api/bottle.rb

@@ -6,7 +6,9 @@ module Homebrew
     module Bottle
       class << self
         def bottle_api_path
-          return generic_bottle_api_path if Homebrew::EnvConfig.force_homebrew_on_linux?
+          return generic_bottle_api_path if
+            Homebrew::EnvConfig.force_homebrew_on_linux? ||
+            Homebrew::EnvConfig.force_homebrew_core_repo_on_linux?
 
           "bottle-linux"
         end

Library/Homebrew/extend/os/linux/api/formula.rb

@@ -6,7 +6,9 @@ module Homebrew
     module Formula
       class << self
         def formula_api_path
-          return generic_formula_api_path if Homebrew::EnvConfig.force_homebrew_on_linux?
+          return generic_formula_api_path if
+            Homebrew::EnvConfig.force_homebrew_on_linux? ||
+            Homebrew::EnvConfig.force_homebrew_core_repo_on_linux?
 
           "formula-linux"
         end

Library/Homebrew/extend/os/linux/tap.rb

@@ -5,6 +5,8 @@ class CoreTap < Tap
   # @private
   def initialize
     super "Homebrew", "core"
-    @full_name = "Homebrew/linuxbrew-core" unless Homebrew::EnvConfig.force_homebrew_on_linux?
+    @full_name = "Homebrew/linuxbrew-core" if
+      !Homebrew::EnvConfig.force_homebrew_on_linux? &&
+      !Homebrew::EnvConfig.force_homebrew_core_repo_on_linux?
   end
 end

Library/Homebrew/sorbet/rbi/hidden-definitions/hidden.rbi

@@ -9817,6 +9817,8 @@ module Homebrew::EnvConfig
 
   def self.force_homebrew_on_linux?(); end
 
+  def self.force_homebrew_core_repo_on_linux?(); end
+
   def self.force_vendor_ruby?(); end
 
   def self.ftp_proxy(); end