own dir for arm tests and split logic off

test/arm/helper.rb

@@ -0,0 +1,29 @@
+require_relative '../helper'
+
+# try  to test that the generation of basic instructions works
+# one instruction at a time, reverse testing from objdump --demangle -Sfghxp
+# tests are named as per assembler code, ie test_mov testing mov instruction
+#  adc add and bic eor orr rsb rsc sbc sub mov mvn cmn cmp teq tst b call bx swi strb
+
+module ArmHelper 
+  # need Assembler and a block (see those classes) 
+  def setup
+    @machine = Arm::ArmMachine.new
+  end
+
+  # code is what the generator spits out, at least one instruction worth (.first)
+  # the op code is wat was witten as assembler in the first place and the binary result
+  # is reversed and in 4 bytes as ruby can only do 31 bits and so we can't test with just one int (?)
+  def assert_code code , op , should
+    assert_equal op ,  code.opcode
+    io = StringIO.new
+    code.assemble(io)
+    binary = io.string
+    assert_equal 4 , binary.length , "code length wrong for #{code.inspect}"
+    index = 0
+    binary.each_byte do |byte |
+      assert_equal should[index] , byte , "byte #{index} 0x#{should[index].to_s(16)} != 0x#{byte.to_s(16)}"
+      index += 1
+    end
+  end
+end