Warn on invalid plugin directories

lib/ohai/loader.rb

@@ -39,7 +39,13 @@ class PluginFile < Struct.new(:path, :plugin_root)
 
       # Finds all the *.rb files under the configured paths in :plugin_path
       def self.find_all_in(plugin_dir)
+        unless Dir.exist?(plugin_dir)
+          Ohai::Log.warn("The plugin path #{plugin_dir} does not exist. Skipping...")
+          return []
+        end
+
         Ohai::Log.debug("Searching for Ohai plugins in #{plugin_dir}")
+
         # escape_glob_dir does not exist in 12.7 or below
         if ChefConfig::PathHelper.respond_to?(:escape_glob_dir)
           escaped = ChefConfig::PathHelper.escape_glob_dir(plugin_dir)

spec/unit/loader_spec.rb

@@ -219,6 +219,14 @@
           expect { loader.load_plugin(path_to("bad_name.rb")) }.not_to raise_error
         end
       end
+
+      describe "when plugin directory does not exist" do
+        it "logs and invalid plugin path warning" do
+          expect(Ohai::Log).to receive(:warn).with(/The plugin path.*does not exist/)
+          allow(Dir).to receive(:exist?).with("/bogus/dir").and_return(false)
+          Ohai::Loader::PluginFile.find_all_in("/bogus/dir")
+        end
+      end
     end
   end
 end