rename assembler to text_writer

as “assembly” really happens in the machine now

test/risc/test_assembler.rb

@@ -1,22 +0,0 @@
-require_relative "../helper"
-
-module Risc
-  class TestAssembler < MiniTest::Test
-
-    def setup
-      @machine = Risc.machine.boot
-    end
-    def test_init
-      @assembler = Assembler.new(@machine)
-    end
-    def test_write_fails
-      @assembler = Assembler.new(@machine)
-      assert_raises{ @assembler.write_as_string} #must translate first
-    end
-    def test_write_space
-      assert @machine.position_all
-      @assembler = Assembler.new(@machine)
-      assert @assembler.write_as_string
-    end
-  end
-end

test/risc/test_text_writer.rb

@@ -0,0 +1,22 @@
+require_relative "../helper"
+
+module Risc
+  class TestTextWriter < MiniTest::Test
+
+    def setup
+      @machine = Risc.machine.boot
+    end
+    def test_init
+      @text_writer = TextWriter.new(@machine)
+    end
+    def test_write_fails
+      @text_writer = TextWriter.new(@machine)
+      assert_raises{ @text_writer.write_as_string} #must translate first
+    end
+    def test_write_space
+      assert @machine.position_all
+      @text_writer = TextWriter.new(@machine)
+      assert @text_writer.write_as_string
+    end
+  end
+end