haskell: top-level decls (fn-clause, type-sig, data, type, newtype, fixity) + type parser (+24 tests, 162/162)

lib/haskell/tests/parser-decls.sx

@@ -0,0 +1,273 @@
+;; Top-level declarations: function clauses, type signatures, data,
+;; type, newtype, fixity. Driven by hk-parse-top which produces
+;; a (:program DECLS) node.
+
+(define
+  hk-prog
+  (fn
+    (&rest decls)
+    (list :program decls)))
+
+;; ── Function clauses & pattern bindings ──
+(hk-test
+  "simple fun-clause"
+  (hk-parse-top "f x = x + 1")
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list :op "+" (list :var "x") (list :int 1)))))
+
+(hk-test
+  "nullary decl"
+  (hk-parse-top "answer = 42")
+  (hk-prog
+    (list :fun-clause "answer" (list) (list :int 42))))
+
+(hk-test
+  "multi-clause fn (separate defs for each pattern)"
+  (hk-parse-top "fact 0 = 1\nfact n = n")
+  (hk-prog
+    (list :fun-clause "fact" (list (list :p-int 0)) (list :int 1))
+    (list
+      :fun-clause
+      "fact"
+      (list (list :p-var "n"))
+      (list :var "n"))))
+
+(hk-test
+  "constructor pattern in fn args"
+  (hk-parse-top "fromJust (Just x) = x")
+  (hk-prog
+    (list
+      :fun-clause
+      "fromJust"
+      (list (list :p-con "Just" (list (list :p-var "x"))))
+      (list :var "x"))))
+
+(hk-test
+  "pattern binding at top level"
+  (hk-parse-top "(a, b) = pair")
+  (hk-prog
+    (list
+      :pat-bind
+      (list
+        :p-tuple
+        (list (list :p-var "a") (list :p-var "b")))
+      (list :var "pair"))))
+
+;; ── Type signatures ──
+(hk-test
+  "single-name sig"
+  (hk-parse-top "f :: Int -> Int")
+  (hk-prog
+    (list
+      :type-sig
+      (list "f")
+      (list :t-fun (list :t-con "Int") (list :t-con "Int")))))
+
+(hk-test
+  "multi-name sig"
+  (hk-parse-top "f, g, h :: Int -> Bool")
+  (hk-prog
+    (list
+      :type-sig
+      (list "f" "g" "h")
+      (list :t-fun (list :t-con "Int") (list :t-con "Bool")))))
+
+(hk-test
+  "sig with type application"
+  (hk-parse-top "f :: Maybe a -> a")
+  (hk-prog
+    (list
+      :type-sig
+      (list "f")
+      (list
+        :t-fun
+        (list :t-app (list :t-con "Maybe") (list :t-var "a"))
+        (list :t-var "a")))))
+
+(hk-test
+  "sig with list type"
+  (hk-parse-top "len :: [a] -> Int")
+  (hk-prog
+    (list
+      :type-sig
+      (list "len")
+      (list
+        :t-fun
+        (list :t-list (list :t-var "a"))
+        (list :t-con "Int")))))
+
+(hk-test
+  "sig with tuple and right-assoc ->"
+  (hk-parse-top "pair :: a -> b -> (a, b)")
+  (hk-prog
+    (list
+      :type-sig
+      (list "pair")
+      (list
+        :t-fun
+        (list :t-var "a")
+        (list
+          :t-fun
+          (list :t-var "b")
+          (list
+            :t-tuple
+            (list (list :t-var "a") (list :t-var "b"))))))))
+
+(hk-test
+  "sig + implementation together"
+  (hk-parse-top "id :: a -> a\nid x = x")
+  (hk-prog
+    (list
+      :type-sig
+      (list "id")
+      (list :t-fun (list :t-var "a") (list :t-var "a")))
+    (list
+      :fun-clause
+      "id"
+      (list (list :p-var "x"))
+      (list :var "x"))))
+
+;; ── data declarations ──
+(hk-test
+  "data Maybe"
+  (hk-parse-top "data Maybe a = Nothing | Just a")
+  (hk-prog
+    (list
+      :data
+      "Maybe"
+      (list "a")
+      (list
+        (list :con-def "Nothing" (list))
+        (list :con-def "Just" (list (list :t-var "a")))))))
+
+(hk-test
+  "data Either"
+  (hk-parse-top "data Either a b = Left a | Right b")
+  (hk-prog
+    (list
+      :data
+      "Either"
+      (list "a" "b")
+      (list
+        (list :con-def "Left" (list (list :t-var "a")))
+        (list :con-def "Right" (list (list :t-var "b")))))))
+
+(hk-test
+  "data with no type parameters"
+  (hk-parse-top "data Bool = True | False")
+  (hk-prog
+    (list
+      :data
+      "Bool"
+      (list)
+      (list
+        (list :con-def "True" (list))
+        (list :con-def "False" (list))))))
+
+(hk-test
+  "recursive data type"
+  (hk-parse-top "data Tree a = Leaf | Node (Tree a) a (Tree a)")
+  (hk-prog
+    (list
+      :data
+      "Tree"
+      (list "a")
+      (list
+        (list :con-def "Leaf" (list))
+        (list
+          :con-def
+          "Node"
+          (list
+            (list :t-app (list :t-con "Tree") (list :t-var "a"))
+            (list :t-var "a")
+            (list :t-app (list :t-con "Tree") (list :t-var "a"))))))))
+
+;; ── type synonyms ──
+(hk-test
+  "simple type synonym"
+  (hk-parse-top "type Name = String")
+  (hk-prog
+    (list :type-syn "Name" (list) (list :t-con "String"))))
+
+(hk-test
+  "parameterised type synonym"
+  (hk-parse-top "type Pair a = (a, a)")
+  (hk-prog
+    (list
+      :type-syn
+      "Pair"
+      (list "a")
+      (list
+        :t-tuple
+        (list (list :t-var "a") (list :t-var "a"))))))
+
+;; ── newtype ──
+(hk-test
+  "newtype"
+  (hk-parse-top "newtype Age = Age Int")
+  (hk-prog (list :newtype "Age" (list) "Age" (list :t-con "Int"))))
+
+(hk-test
+  "parameterised newtype"
+  (hk-parse-top "newtype Wrap a = Wrap a")
+  (hk-prog
+    (list :newtype "Wrap" (list "a") "Wrap" (list :t-var "a"))))
+
+;; ── fixity declarations ──
+(hk-test
+  "infixl with precedence"
+  (hk-parse-top "infixl 5 +:, -:")
+  (hk-prog (list :fixity "l" 5 (list "+:" "-:"))))
+
+(hk-test
+  "infixr"
+  (hk-parse-top "infixr 9 .")
+  (hk-prog (list :fixity "r" 9 (list "."))))
+
+(hk-test
+  "infix (non-assoc) default prec"
+  (hk-parse-top "infix ==")
+  (hk-prog (list :fixity "n" 9 (list "=="))))
+
+(hk-test
+  "fixity with backtick operator name"
+  (hk-parse-top "infixl 7 `div`")
+  (hk-prog (list :fixity "l" 7 (list "div"))))
+
+;; ── Several decls combined ──
+(hk-test
+  "mixed: data + sig + fn + type"
+  (hk-parse-top "data Maybe a = Nothing | Just a\ntype Entry = Maybe Int\nf :: Entry -> Int\nf (Just x) = x\nf Nothing = 0")
+  (hk-prog
+    (list
+      :data
+      "Maybe"
+      (list "a")
+      (list
+        (list :con-def "Nothing" (list))
+        (list :con-def "Just" (list (list :t-var "a")))))
+    (list
+      :type-syn
+      "Entry"
+      (list)
+      (list :t-app (list :t-con "Maybe") (list :t-con "Int")))
+    (list
+      :type-sig
+      (list "f")
+      (list :t-fun (list :t-con "Entry") (list :t-con "Int")))
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-con "Just" (list (list :p-var "x"))))
+      (list :var "x"))
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-con "Nothing" (list)))
+      (list :int 0))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}