Create emitter

test/Assembler/EmitterSpec.hs

@@ -0,0 +1,47 @@
+module Assembler.EmitterSpec where
+
+import Test.Hspec
+
+import qualified Data.Map as M
+
+
+import Assembler.Tokenizer (tokenize)
+import Assembler.Parser (parse)
+import Assembler.Emitter
+
+spec :: Spec
+spec = do
+  describe "resolveLabels" $ do
+    it "replaces reference with actual byte number" $ do
+      let beans = [ Byte 1, Byte 2, Reference "main", Byte 4 ]
+      let labels = M.fromList [("main", 3)]
+      resolveLabels labels beans `shouldBe` Right [Byte 1, Byte 2, Byte 3, Byte 4]
+    it "throws error if label does not exist" $ do
+      let beans = [ Byte 1, Byte 2, Reference "not_existing_label", Byte 4 ]
+      let labels = M.fromList [("main", 3)]
+      resolveLabels labels beans `shouldBe` Left "Label 'not_existing_label' is not defined"
+
+  describe "emit" $ do
+    it "label resolution works" $ do
+      let input = "main: \n\
+                  \push 1\n\
+                  \push 2\n\
+                  \jmp &sum\n\
+                  \\n\
+                  \sum: add\n\
+                  \jmp &main"      
+      let (Right tokens) = tokenize input
+      let (Right ast) = parse tokens
+      let expected = [0x02, 0x01, 0x02, 0x02, 0x0e, 0x06, 0x06, 0x0e, 0x00]
+      emit ast `shouldBe` Right expected
+    it "raises error if label has not been defined" $ do
+      let input = "main: \n\
+                  \push 1\n\
+                  \push 2\n\
+                  \jmp &sum\n\
+                  \\n\
+                  \sum: add\n\
+                  \jmp &program"      
+      let (Right tokens) = tokenize input
+      let (Right ast) = parse tokens      
+      emit ast `shouldBe` Left "Label 'program' is not defined"