simplify: no distinction between generic types and 'normal' types.

tests/generics.js

@@ -0,0 +1,67 @@
+import assert from "node:assert";
+import { assignFn, makeGeneric, unify, UnifyError } from "../lib/generics/generics.js";
+import { getDefaultTypeParser } from "../lib/parser/type_parser.js";
+import { prettyT } from "../lib/util/pretty.js";
+
+const mkType = getDefaultTypeParser();
+
+// It would be better to compare the types directly with 'compareTypes', but the assert-module does not allow passing a custom comparison function.
+
+assert.equal(
+  // actual
+  prettyT(
+    unify(
+      mkType("(a -> Int)"),
+      makeGeneric(() => mkType("[Bool] -> Int")),
+    )
+  ),
+  // expected
+  "([Bool] -> Int)",
+);
+
+assert.equal(
+  // actual
+  prettyT(
+    unify(
+      mkType("(a -> a) -> b"),
+      mkType("(Bool -> Bool) -> a"),
+    )
+  ),
+  // expected
+  "((Bool -> Bool) -> a)",
+);
+
+assert.equal(
+  // actual
+  prettyT(
+    assignFn(
+      mkType("(a -> b) -> [a] -> [b]"),
+      mkType("a -> a")
+    )
+  ),
+  // expected
+  "([a] -> [a])",
+);
+
+assert.equal(
+  // actual
+  prettyT(
+    assignFn(
+      mkType("(a -> Int) -> [a] -> a"),
+      mkType("a -> a")
+    )
+  ),
+  // expected
+  "([Int] -> Int)",
+);
+
+assert.throws(
+  () => {
+    unify(
+      mkType("Int"),
+      mkType("Bool")
+    )
+  },
+  // expected error
+  UnifyError,
+);

tests/parser.js

@@ -0,0 +1,47 @@
+import assert from "node:assert";
+import { getDefaultTypeParser }from "../lib/parser/type_parser.js";
+import { prettyT } from "../lib/util/pretty.js";
+
+const parse = getDefaultTypeParser();
+
+assert.equal(
+  // actual
+  prettyT(parse("Int")),
+  // expected
+  "Int",
+);
+
+assert.equal(
+  // actual
+  prettyT(parse("Int * Bool")),
+  // expected
+  "(Int ⨯ Bool)",
+);
+
+assert.equal(
+  // actual
+  prettyT(parse("(((((((Int)))) => ((Bool)))))")),
+  // expected
+  "(Int => Bool)",
+);
+
+assert.equal(
+  // actual
+  prettyT(parse("#0((Int * #0) + Unit)")),
+  // expected
+  "#0((Int ⨯ #0) + Unit)",
+);
+
+assert.equal(
+  // actual
+  prettyT(parse("#0((a * #0) + Unit")),
+  // expected
+  "#0((a ⨯ #0) + Unit)",
+);
+
+assert.equal(
+  // actual
+  prettyT(parse("(a*b) + (c*d)")),
+  // expected
+  "((a ⨯ b) + (c ⨯ d))",
+);