added spec

ascandone · Jan 17, 2024 · cd88e3d · cd88e3d
1 parent cb12a4e
commit cd88e3d
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Showing 2 changed files with 15 additions and 2 deletions.
diff --git a/src/typecheck/typecheck.test.ts b/src/typecheck/typecheck.test.ts
@@ -59,6 +59,19 @@ test("infer a variable not present in the context", () => {
   });
 });
 
+test("typechecking previously defined vars", () => {
+  const [types, errors] = tc(`
+    let x = 42
+    let y = x
+  `);
+
+  expect(errors).toEqual([]);
+  expect(types).toEqual({
+    x: "Int",
+    y: "Int",
+  });
+});
+
 function tc(src: string, context: Context = {}) {
   const parsedProgram = unsafeParse(src);
   const [typed, errors] = typecheck(parsedProgram, context);

diff --git a/src/typecheck/typecheck.ts b/src/typecheck/typecheck.ts
@@ -23,13 +23,13 @@ export function typecheck<T = {}>(
 ): [Program<T & TypeMeta>, TypeError<Expr<T & TypeMeta>>[]] {
   TVar.resetId();
   const errors: TypeError<Expr<T & TypeMeta>>[] = [];
-  const context: Context = { ...initialContext };
+  let context: Context = { ...initialContext };
 
   const typedStatements = ast.statements.map<Statement<T & TypeMeta>>(
     (decl) => {
       const annotated = annotateExpr(decl.value);
       errors.push(...typecheckAnnotatedExpr(annotated, context));
-      // TODO save bindings in context
+      context[decl.binding.name] = annotated.$.asType();
       return {
         ...decl,
         binding: { ...decl.binding, $: annotated.$ },