Additional test cases and bug fixes for subtle issues

test/Spec.hs

@@ -5,6 +5,7 @@ import Lexer
 import Parser
 import Research
 
+import Control.Exception (evaluate, try, SomeException)
 import qualified Data.Map as Map
 import Test.Tasty
 import Test.Tasty.HUnit
@@ -58,6 +59,27 @@ parserTests = testGroup "Parser Tests"
       let input = "t t t"
       let expected = TFork TLeaf TLeaf
       parseSapling input @?= expected
+
+  , testCase "Parse mixed list literals" $ do
+      -- You must put non-listliterals in parentheses
+      let input = "[t (\"hello\") t]" 
+      let expected = SList [TLeaf, SStr "hello", TLeaf]
+      parseSapling input @?= expected
+
+  , testCase "Parse function with applications" $ do
+      let input = "f x = t x"
+      let expected = SFunc "f" ["x"] (SApp TLeaf [SVar "x"])
+      parseSapling input @?= expected
+
+  , testCase "Parse nested lists" $ do
+      let input = "[t [(t t)]]"
+      let expected = SList [TLeaf, SList [TStem TLeaf]]
+      parseSapling input @?= expected
+
+  , testCase "Parse complex parentheses" $ do
+      let input = "t (t t (t t))"
+      let expected = TStem (TFork TLeaf (TStem TLeaf))
+      parseSapling input @?= expected
   ]
 
 integrationTests :: TestTree
@@ -138,4 +160,3 @@ propertyTests = testGroup "Property Tests"
           Left _ -> property True
           Right ast -> parseSapling input === ast
   ]
-