Add test

src/__tests__/__snapshots__/compiler.test.ts.snap

@@ -0,0 +1,32 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`E2E Compiler Pipeline > Compiler can do tco 1`] = `
+"(module
+ (type $0 (func (param i32 i32 i32) (result i32)))
+ (memory $0 1 150)
+ (export "buffer" (memory $0))
+ (export "fib" (func $fib#15065))
+ (func $fib#15065 (type $0) (param $0 i32) (param $1 i32) (param $2 i32) (result i32)
+  (if (result i32)
+   (local.get $0)
+   (then
+    (return_call $fib#15065
+     (i32.sub
+      (local.get $0)
+      (i32.const 1)
+     )
+     (local.get $2)
+     (i32.add
+      (local.get $1)
+      (local.get $2)
+     )
+    )
+   )
+   (else
+    (local.get $1)
+   )
+  )
+ )
+)
+"
+`;

src/__tests__/compiler.test.ts

@@ -1,6 +1,6 @@
-import { e2eVoidText, gcVoidText } from "./fixtures/e2e-file.js";
+import { e2eVoidText, gcVoidText, tcoText } from "./fixtures/e2e-file.js";
 import { compile } from "../compiler.js";
-import { describe, test } from "vitest";
+import { describe, expect, test } from "vitest";
 import assert from "node:assert";
 import { getWasmFn, getWasmInstance } from "../lib/wasm.js";
 
@@ -35,4 +35,10 @@ describe("E2E Compiler Pipeline", () => {
     t.expect(test5(), "test 5 returns correct value").toEqual(21);
     t.expect(test6(), "test 6 returns correct value").toEqual(-1);
   });
+
+  test("Compiler can do tco", async (t) => {
+    const mod = await compile(tcoText);
+    mod.optimize();
+    t.expect(mod.emitText()).toMatchSnapshot();
+  });
 });

src/__tests__/fixtures/e2e-file.ts

@@ -86,3 +86,14 @@ pub fn test6()
   let vec = Bitly { x: 52, y: 2, z: 21 }
   get_num_from_vec_sub_obj(vec)
 `;
+
+export const tcoText = `
+use std::all
+
+// Tail call fib
+pub fn fib(n: i32, a: i32, b: i32) -> i32
+  if n == 0 then:
+    a
+  else:
+    fib(n - 1, b, a + b)
+`;