Add initial truthy? and falsy? inlined compiler helpers (#419)

Author: adambeynon

lib/opal/nodes/call.rb

@@ -1,5 +1,6 @@
 require 'set'
 require 'opal/nodes/base'
+require 'opal/nodes/runtime_helpers'
 
 module Opal
   module Nodes
@@ -99,6 +100,9 @@ def handle_special
             push result
           return true
           end
+        elsif RuntimeHelpers.compatible?(recvr, meth, arglist)
+          push(RuntimeHelpers.new(@sexp, @level, @compiler).compile)
+          return true
         end
       end
 

lib/opal/nodes/runtime_helpers.rb

@@ -0,0 +1,45 @@
+require 'set'
+require 'opal/nodes/base'
+
+module Opal
+  module Nodes
+    class RuntimeHelpers < Base
+      HELPERS = Set.new
+
+      children :recvr, :meth, :arglist
+
+      def self.compatible?(recvr, meth, arglist)
+        recvr == [:const, :Opal] and HELPERS.include?(meth.to_sym)
+      end
+
+      def self.helper(name, &block)
+        HELPERS << name
+        define_method("compile_#{name}", &block)
+      end
+
+      def compile
+        if HELPERS.include?(meth.to_sym)
+          __send__("compile_#{meth}")
+        else
+          raise "Helper not supported: #{meth}"
+        end
+      end
+
+      helper :truthy? do
+        unless sexp = arglist[1]
+          raise "truthy? requires an object"
+        end
+
+        js_truthy(sexp)
+      end
+
+      helper :falsy? do
+        unless sexp = arglist[1]
+          raise "falsy? requires an object"
+        end
+
+        js_falsy(sexp)
+      end
+    end
+  end
+end

opal/core/helpers.rb

@@ -51,22 +51,6 @@ def self.fits_array!(value)
     end
   end
 
-  def self.truthy?(value)
-    if value
-      true
-    else
-      false
-    end
-  end
-
-  def self.falsy?(value)
-    if value
-      false
-    else
-      true
-    end
-  end
-
   def self.destructure(args)
     %x{
       if (args.length == 1) {