[WIP] Simple example to show the required behavior when building against sy…

.github/workflows/regression-with-system-php.yml

@@ -0,0 +1,42 @@
+name: Against System PHP
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: ${{ matrix.operating-system }}
+    strategy:
+      fail-fast: false      
+      matrix:
+        operating-system: [macos-latest]
+        php-versions: ['7.3']
+        phalcon: [3.4, 4.0RC2, 4.0rc3, 73_4.0.0]
+    name: Building Phalcon@${{matrix.phalcon}} Test on ${{ matrix.operating-system }}
+    steps:
+    - name: Checkout
+      uses: actions/checkout@master
+    - name: Add Phalcon Tap
+      run: brew tap phalcon/extension .
+    - name: Install official php 7.3
+      run: brew install php@7.3
+    - name: Force Link Unoffical PHP 7.3
+      run: brew link --force --overwrite php@7.3
+    - name: Try to Install Phalcon
+      run: brew install phalcon@${{matrix.phalcon}} --without-homebrew-php
+    - name: Testing ini values 3.4
+      if: matrix.phalcon == '3.4'
+      run: |
+        php -r "echo 'xdebug: '.extension_loaded('xdebug');"
+        php -r "echo 'phalcon: ' . phpversion('phalcon').\"\n\";"
+        php -r "if(! extension_loaded('phalcon')) {throw new Exception('phalcon not found');}"
+        php -r "if(phpversion('phalcon')!='3.4.5') {throw new Exception('Wrong phalcon version Installed '. phpversion('phalcon'));}"
+    - name: Testing ini values RC
+      if: contains( matrix.phalcon, 'rc' )
+      run: |
+        php -r "echo 'xdebug: '.extension_loaded('xdebug');"
+        php -r "echo 'psr: ' . phpversion('psr').\"\n\";"
+        php -r "echo 'phalcon: ' . phpversion('phalcon').\"\n\";"
+        php -r "if(! extension_loaded('psr')) {throw new Exception('psr not found');}"
+        php -r "if(! extension_loaded('phalcon')) {throw new Exception('phalcon not found');}"
+        php -r "if(phpversion('phalcon')!='4.0.0') {throw new Exception('Wrong phalcon version Installed '. phpversion('phalcon'));}"
+

Abstract/abstract-php-extension.rb

@@ -88,7 +88,7 @@ def safe_phpize
 
   def phpize
     if build.without? "homebrew-php"
-      "phpize"
+      ENV["HOMEBREW_PHPIZE"] || "phpize"
     else
       "#{Formula[php_formula].opt_bin}/phpize"
     end
@@ -104,7 +104,11 @@ def phpini
 
   def phpconfig
     if build.without? "homebrew-php"
-      ""
+      if (ENV["HOMEBREW_PHP_CONFIG"])
+        "--with-php-config=#{ENV["HOMEBREW_PHP_CONFIG"]}"
+      else
+        ""
+      end
     else
       "--with-php-config=#{Formula[php_formula].opt_bin}/php-config"
     end

Formula/phalcon@3.4.rb

@@ -17,6 +17,7 @@ class PhalconAT34 < AbstractPhp73Extension
   def install
     Dir.chdir "build/php7/64bits"
 
+    raise
     safe_phpize
     system "./configure", "--prefix=#{prefix}", phpconfig, "--enable-phalcon"
     system "make"

Formula/phalcon@4.0.0.rb

@@ -11,6 +11,7 @@ class PhalconAT400 < AbstractPhp74Extension
   bottle do
     cellar :any_skip_relocation
     root_url "https://github.com/phalcon/homebrew-tap/releases/download/v4.0.x"
+    sha256 "607eaf8613d7d02dd0529fd641978e2a814cb525d502ab882aded143bcda97e4" => :catalina
     sha256 "e645dfbf9cb485380f7cd92740dc5dcd30f8b6f4b9051ee3f8ec11f903e9243a" => :mojave
     sha256 "2b827bbdd2b52f136af1cfa1e209457f0264c5d9a0804345982e0a57d50aa940" => :high_sierra
     sha256 "8f04465129e223fa9e261a73ce3a9d7cdecf6786890c854bd38b560852ed6ec6" => :sierra