[Truffle] Add Kernel#test to kernel.rb.

Author: bjfish

spec/truffle/tags/core/kernel/test_tags.txt

@@ -1,15 +1,3 @@
-fails:Kernel#test is a private method
-fails:Kernel#test returns true when passed ?f if the argument is a regular file
-fails:Kernel#test returns true when passed ?e if the argument is a file
-fails:Kernel#test returns true when passed ?d if the argument is a directory
-fails:Kernel#test returns true when passed ?l if the argument is a symlink
-fails:Kernel#test returns true when passed ?r if the argument is readable by the effective uid
-fails:Kernel#test returns true when passed ?R if the argument is readable by the real uid
-fails:Kernel#test returns true when passed ?w if the argument is readable by the effective uid
-fails:Kernel#test returns true when passed ?W if the argument is readable by the real uid
-fails:Kernel#test calls #to_path on second argument when passed ?f and a filename
-fails:Kernel#test calls #to_path on second argument when passed ?e and a filename
-fails:Kernel#test calls #to_path on second argument when passed ?d and a directory
 fails:Kernel#test time commands returns the last access time for the provided file when passed ?A
 fails:Kernel#test time commands returns the time at which the file was created when passed ?C
 fails:Kernel#test time commands returns the time at which the file was modified when passed ?M

truffle/src/main/ruby/core/rubinius/common/kernel.rb

@@ -228,6 +228,36 @@ def tap
     self
   end
 
+  def test(cmd, file1, file2=nil)
+    case cmd
+      when ?d
+        File.directory? file1
+      when ?e
+        File.exist? file1
+      when ?f
+        File.file? file1
+      when ?l
+        File.symlink? file1
+      when ?r
+        File.readable? file1
+      when ?R
+        File.readable_real? file1
+      when ?w
+        File.writable? file1
+      when ?W
+        File.writable_real? file1
+      when ?A
+        File.atime file1
+      when ?C
+        File.ctime file1
+      when ?M
+        File.mtime file1
+      else
+        raise NotImplementedError, "command ?#{cmd.chr} not implemented"
+    end
+  end
+  module_function :test
+
   def open(obj, *rest, &block)
     if obj.respond_to?(:to_open)
       obj = obj.to_open(*rest)