Iterate on finding a database

ext/mimemagic/Rakefile

@@ -2,22 +2,22 @@ require "rubygems"
 require "rake/clean"
 
 def locate_mime_database
-  # User provided path.
-  unless ENV["FREEDESKTOP_MIME_TYPES_PATH"].nil?
-    path = File.expand_path(ENV["FREEDESKTOP_MIME_TYPES_PATH"])
-    unless File.exist?(path)
-      raise "The path #{path} was provided for the MIME types database, but no file exists at that path."
-    end
-    return path
-  end
-
-  # Default path on Linux installs for the MIME types database.
-  return "/usr/share/mime/packages/freedesktop.org.xml" if File.exist?("/usr/share/mime/packages/freedesktop.org.xml")
-
-  # Default path when installed with Homebrew
-  return "/usr/local/Cellar/shared-mime-info/2.1/share/shared-mime-info/packages/freedesktop.org.xml" if File.exist?("/usr/local/Cellar/shared-mime-info/2.1/share/shared-mime-info/packages/freedesktop.org.xml")
-
-  raise "No database of MIME types could be found. Ensure you have either installed the shared-mime-types package for your distribution, or obtain a version of freedesktop.org.xml, and set FREEDESKTOP_MIME_TYPES_PATH to the location of that file."
+  possible_paths = [
+    (File.expand_path(ENV["FREEDESKTOP_MIME_TYPES_PATH"]) if ENV["FREEDESKTOP_MIME_TYPES_PATH"]),
+    "/usr/local/share/mime/packages/freedesktop.org.xml",
+    "/opt/homebrew/share/mime/packages/freedesktop.org.xml",
+    "/usr/share/mime/packages/freedesktop.org.xml"
+  ].compact
+  path = possible_paths.find { |candidate| File.exist?(candidate) }
+  
+  return path unless path.nil?
+  raise(<<~ERROR)
+   Could not find MIME type database in the following locations: #{possible_paths}
+   
+   Ensure you have either installed the shared-mime-types package for your distribution, or 
+   obtain a version of freedesktop.org.xml and set FREEDESKTOP_MIME_TYPES_PATH to the location 
+   of that file.
+  ERROR
 end
 
 desc "Build a file pointing at the database"