allow processors to be activated by string

2 files changed, 67 insertions, 8 deletions

diff --git a/lib/asciidoctor/extensions.rb b/lib/asciidoctor/extensions.rb
index fe0cbaf7..e5f7173e 100644
--- a/lib/asciidoctor/extensions.rb
+++ b/lib/asciidoctor/extensions.rb
@@ -27,18 +27,24 @@ module Extensions
     def register extension = nil, &block
       if block_given?
         registered << block
-      elsif !extension.nil?
-        if extension.is_a? Class
-          registered << extension
-        else
-          registered << class_for_name(extension)
-        end
+      elsif extension
+        registered << resolve_class(extension)
       end 
     end
 
+    def resolve_class(object)
+      object.is_a?(Class) ? object : class_for_name(object.to_s)
+    end
+
     def class_for_name(qualified_name)
       qualified_name.split('::').inject(Object) do |module_, name|
-        module_.const_get(name)
+        if name.empty?
+          module_
+        elsif module_.const_defined? name
+          module_.const_get(name)
+        else
+          raise "Could not resolve class for name: #{qualified_name}"
+        end
       end
     end
 
@@ -80,6 +86,7 @@ module Extensions
     end 
 
     def preprocessor processor, position = :<<
+      processor = resolve_processor_class processor
       if position == :<< || @preprocessors.empty?
         @preprocessors.push processor
       elsif position == :>>
@@ -100,6 +107,7 @@ module Extensions
     end
 
     def treeprocessor processor, position = :<<
+      processor = resolve_processor_class processor
       if position == :<< || @treeprocessors.empty?
         @treeprocessors.push processor
       elsif position == :>>
@@ -120,6 +128,7 @@ module Extensions
     end
 
     def postprocessor processor, position = :<<
+      processor = resolve_processor_class processor
       if position == :<< || @postprocessors.empty?
         @postprocessors.push processor
       elsif position == :>>
@@ -140,6 +149,7 @@ module Extensions
     end
 
     def include_processor processor, position = :<<
+      processor = resolve_processor_class processor
       if position == :<< || @include_processors.empty?
         @include_processors.push processor
       elsif position == :>>
@@ -165,6 +175,7 @@ module Extensions
 
     # TODO allow contexts to be specified here, perhaps as [:upper, [:paragraph, :sidebar]]
     def block name, processor, delimiter = nil, &block
+      processor = resolve_processor_class processor
       @blocks[name] = processor
       if block_given?
         @block_delimiters[block] = name
@@ -210,6 +221,7 @@ module Extensions
     end
 
     def block_macro name, processor
+      processor = resolve_processor_class processor
       @block_macros[name.to_s] = processor
     end
 
@@ -227,6 +239,7 @@ module Extensions
 
     # TODO probably need ordering control before/after other inline macros
     def inline_macro name, processor
+      processor = resolve_processor_class processor
       @inline_macros[name.to_s] = processor
     end
 
@@ -252,6 +265,10 @@ module Extensions
       instance_exec document, &block
     end
 
+    def resolve_processor_class object
+      ::Asciidoctor::Extensions.resolve_class object
+    end
+
     def reset
       @block_processor_cache = {}
       @block_macro_processor_cache = {}
diff --git a/test/extensions_test.rb b/test/extensions_test.rb
index d6a59d58..4140ed6c 100644
--- a/test/extensions_test.rb
+++ b/test/extensions_test.rb
@@ -145,11 +145,44 @@ context 'Extensions' do
       end
     end
 
-    test 'should get class for name' do
+    test 'should get class for top-level class name' do
+      clazz = Asciidoctor::Extensions.class_for_name('Asciidoctor')
+      assert_not_nil clazz
+      assert_equal Asciidoctor, clazz
+    end
+
+    test 'should get class for class name in module' do
       clazz = Asciidoctor::Extensions.class_for_name('Asciidoctor::Extensions')
       assert_not_nil clazz
       assert_equal Asciidoctor::Extensions, clazz
     end
+
+    test 'should get class for class name resolved from root' do
+      clazz = Asciidoctor::Extensions.class_for_name('::Asciidoctor::Extensions')
+      assert_not_nil clazz
+      assert_equal Asciidoctor::Extensions, clazz
+    end
+
+    test 'should raise exception if cannot find class for name' do
+      begin
+      clazz = Asciidoctor::Extensions.class_for_name('InvalidModule::InvalidClass')
+      flunk 'Expecting RuntimeError to be raised'
+      rescue RuntimeError => e
+        assert_equal 'Could not resolve class for name: InvalidModule::InvalidClass', e.message
+      end
+    end
+
+    test 'should resolve class if class is given' do
+      clazz = Asciidoctor::Extensions.resolve_class(Asciidoctor::Extensions)
+      assert_not_nil clazz
+      assert_equal Asciidoctor::Extensions, clazz
+    end
+
+    test 'should resolve class if class from string' do
+      clazz = Asciidoctor::Extensions.resolve_class('Asciidoctor::Extensions')
+      assert_not_nil clazz
+      assert_equal Asciidoctor::Extensions, clazz
+    end
   end
 
   context 'Activate' do
@@ -262,6 +295,15 @@ context 'Extensions' do
       processor = registry.load_inline_macro_processor 'sample', Asciidoctor::Document.new
       assert processor.is_a? SampleInlineMacro
     end
+
+    test 'should allow processors to be registered by a string name' do
+      registry = Asciidoctor::Extensions::Registry.new
+      registry.preprocessor 'SamplePreprocessor'
+      assert registry.preprocessors?
+      processors = registry.load_preprocessors Asciidoctor::Document.new
+      assert_equal 1, processors.size
+      assert processors.first.is_a? SamplePreprocessor
+    end
   end
 
   context 'Integration' do