add proper handling of ImageOptim.respond_to?

Author: toy

CHANGELOG.markdown

@@ -2,6 +2,8 @@
 
 ## unreleased
 
+* Add proper handling of `ImageOptim.respond_to?` [@toy](https://github.com/toy)
+
 ## v0.23.0 (2016-07-17)
 
 * Added `cache_dir` and `cache_worker_digests` options to cache results [#83](https://github.com/toy/image_optim/issues/83) [@gpakosz](https://github.com/gpakosz)

lib/image_optim.rb

@@ -168,25 +168,43 @@ def optimize_images_data(datas, &block)
     run_method_for(datas, :optimize_image_data, &block)
   end
 
-  # Optimization methods with default options
-  def self.method_missing(method, *args, &block)
-    if method_defined?(method) && method.to_s =~ /^optimize_image/
-      new.send(method, *args, &block)
-    else
-      super
+  class << self
+    # Optimization methods with default options
+    def method_missing(method, *args, &block)
+      if optimize_image_method?(method)
+        new.send(method, *args, &block)
+      else
+        super
+      end
     end
-  end
 
-  # Version of image_optim gem spec loaded
-  def self.version
-    Gem.loaded_specs['image_optim'].version.to_s
-  rescue
-    'DEV'
-  end
+    def respond_to_missing?(method, include_private = false)
+      optimize_image_method?(method) || super
+    end
 
-  # Full version of image_optim
-  def self.full_version
-    "image_optim v#{version}"
+    if RUBY_VERSION < '1.9'
+      def respond_to?(method, include_private = false)
+        optimize_image_method?(method) || super
+      end
+    end
+
+    # Version of image_optim gem spec loaded
+    def version
+      Gem.loaded_specs['image_optim'].version.to_s
+    rescue
+      'DEV'
+    end
+
+    # Full version of image_optim
+    def full_version
+      "image_optim v#{version}"
+    end
+
+  private
+
+    def optimize_image_method?(method)
+      method_defined?(method) && method.to_s =~ /^optimize_image/
+    end
   end
 
   # Are there workers for file at path?

spec/image_optim_spec.rb

@@ -227,4 +227,33 @@ def temp_copy(image)
       end
     end
   end
+
+  %w[
+    optimize_image
+    optimize_image!
+    optimize_image_data
+    optimize_images
+    optimize_images!
+    optimize_images_data
+  ].each do |method|
+    describe ".#{method}" do
+      it 'is checkable by respond_to?' do
+        expect(ImageOptim).to respond_to(method)
+      end
+
+      it 'calls same method on a new ImageOptim instance' do
+        image_optim = instance_double(ImageOptim)
+        method_arg = double
+        method_block = proc{ :x }
+
+        allow(ImageOptim).to receive(:new).and_return(image_optim)
+        expect(image_optim).to receive(method) do |arg, &block|
+          expect(arg).to eq(method_arg)
+          expect(block).to eq(method_block)
+        end
+
+        ImageOptim.send(method, method_arg, &method_block)
+      end
+    end
+  end
 end