vim, macvim: fix and test python linking.

Closes Homebrew/legacy-homebrew#32056.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Formula/macvim.rb

@@ -68,6 +68,8 @@ def install
     if build.with? "python3"
       args << "--enable-python3interp"
     elsif build.with? "python"
+      ENV.prepend "LDFLAGS", `python-config --ldflags`.chomp
+      ENV.prepend "CFLAGS", `python-config --cflags`.chomp
       args << "--enable-pythoninterp"
     end
 
@@ -111,4 +113,20 @@ def caveats
       EOS
     end
   end
+
+  test do
+    # Simple test to check if MacVim was linked to Python version in $PATH
+    if build.with? "python"
+      vim_path = prefix/"MacVim.app/Contents/MacOS/Vim"
+
+      # Get linked framework using otool
+      otool_output = `otool -L #{vim_path} | grep -m 1 Python`.gsub(/\(.*\)/, "").strip.chomp
+
+      # Expand the link and get the python exec path
+      vim_framework_path = Pathname.new(otool_output).realpath.dirname.to_s.chomp
+      system_framework_path = `python-config --exec-prefix`.chomp
+
+      assert_equal system_framework_path, vim_framework_path
+    end
+  end
 end

Formula/vim.rb

@@ -92,4 +92,20 @@ def install
     system "make", "install", "prefix=#{prefix}", "STRIP=true"
     bin.install_symlink "vim" => "vi" if build.include? "override-system-vi"
   end
+
+  test do
+    # Simple test to check if Vim was linked to Python version in $PATH
+    if build.with? "python"
+      vim_path = bin/"vim"
+
+      # Get linked framework using otool
+      otool_output = `otool -L #{vim_path} | grep -m 1 Python`.gsub(/\(.*\)/, "").strip.chomp
+
+      # Expand the link and get the python exec path
+      vim_framework_path = Pathname.new(otool_output).realpath.dirname.to_s.chomp
+      system_framework_path = `python-config --exec-prefix`.chomp
+
+      assert_equal system_framework_path, vim_framework_path
+    end
+  end
 end