safe values should be raw (#792)

@joeldrapper @willcosgrove 
so I made `html_safe` and `safe` consistent in this pr and also created
`__implicit_output__` and made `plain` use old `__text__` instead so we
can render `html_safe` as `raw` by default, unless it's `plain`. Does
that look good?

lib/phlex/sgml.rb

@@ -271,7 +271,7 @@ def yield_content
 
 		original_length = buffer.bytesize
 		content = yield(self)
-		__text__(content) if original_length == buffer.bytesize
+		__implicit_output__(content) if original_length == buffer.bytesize
 
 		nil
 	end
@@ -283,7 +283,7 @@ def __yield_content_with_no_args__
 
 		original_length = buffer.bytesize
 		content = yield
-		__text__(content) if original_length == buffer.bytesize
+		__implicit_output__(content) if original_length == buffer.bytesize
 
 		nil
 	end
@@ -295,11 +295,36 @@ def __yield_content_with_args__(*)
 
 		original_length = buffer.bytesize
 		content = yield(*)
-		__text__(content) if original_length == buffer.bytesize
+		__implicit_output__(content) if original_length == buffer.bytesize
 
 		nil
 	end
 
+	def __implicit_output__(content)
+		context = @_context
+		return true if context.fragments && !context.in_target_fragment
+
+		case content
+		when Phlex::SGML::SafeObject
+			context.buffer << content.to_s
+		when String
+			context.buffer << Phlex::Escape.html_escape(content)
+		when Symbol
+			context.buffer << Phlex::Escape.html_escape(content.name)
+		when nil
+			nil
+		else
+			if (formatted_object = format_object(content))
+				context.buffer << Phlex::Escape.html_escape(formatted_object)
+			else
+				return false
+			end
+		end
+
+		true
+	end
+
+	# same as __implicit_output__ but escapes even `safe` objects
 	def __text__(content)
 		context = @_context
 		return true if context.fragments && !context.in_target_fragment

lib/phlex/sgml/elements.rb

@@ -40,14 +40,14 @@ def #{method_name}(**attributes)
 						content = yield(self)
 						if original_length == buffer.bytesize
 							case content
+							when ::Phlex::SGML::SafeObject
+								buffer << content.to_s
 							when String
 								buffer << ::Phlex::Escape.html_escape(content)
 							when Symbol
 								buffer << ::Phlex::Escape.html_escape(content.name)
 							when nil
 								nil
-							when ::Phlex::SGML::SafeObject
-								buffer << content.to_s
 							else
 								if (formatted_object = format_object(content))
 									buffer << ::Phlex::Escape.html_escape(formatted_object)
@@ -67,14 +67,14 @@ def #{method_name}(**attributes)
 						content = yield(self)
 						if original_length == buffer.bytesize
 							case content
+							when ::Phlex::SGML::SafeObject
+								buffer << content.to_s
 							when String
 								buffer << ::Phlex::Escape.html_escape(content)
 							when Symbol
 								buffer << ::Phlex::Escape.html_escape(content.name)
 							when nil
 								nil
-							when ::Phlex::SGML::SafeObject
-								buffer << content.to_s
 							else
 								if (formatted_object = format_object(content))
 									buffer << ::Phlex::Escape.html_escape(formatted_object)