test: add cases covering recursive functions (#359)

CHANGELOG.md

@@ -9,6 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Tests for recursive functions: PR [#359](https://github.com/tact-lang/tact/pull/359)
+
 ### Changed
 
 - Refactor AST types to simplify access to third-party tools: PR [#325](https://github.com/tact-lang/tact/pull/325)

src/test/feature-recursion.spec.ts

@@ -0,0 +1,31 @@
+import { toNano } from "@ton/core";
+import { ContractSystem } from "@tact-lang/emulator";
+import { __DANGER_resetNodeId } from "../grammar/ast";
+import { RecursionTester } from "./features/output/recursion_RecursionTester";
+
+describe("feature-recursion", () => {
+    beforeEach(() => {
+        __DANGER_resetNodeId();
+    });
+    it("should perform recursive operations correctly", async () => {
+        const system = await ContractSystem.create();
+        const treasure = system.treasure("treasure");
+        const contract = system.open(await RecursionTester.fromInit());
+        await contract.send(
+            treasure,
+            { value: toNano("10") },
+            { $$type: "Deploy", queryId: 0n },
+        );
+        await system.run();
+
+        expect(await contract.getFib(0n)).toBe(0n);
+        expect(await contract.getFib(1n)).toBe(1n);
+        expect(await contract.getFib(2n)).toBe(1n);
+        expect(await contract.getFib(3n)).toBe(2n);
+
+        expect(await contract.getFact(0n)).toBe(1n);
+        expect(await contract.getFact(1n)).toBe(1n);
+        expect(await contract.getFact(2n)).toBe(2n);
+        expect(await contract.getFact(3n)).toBe(6n);
+    });
+});

src/test/features/recursion.tact

@@ -0,0 +1,18 @@
+import "@stdlib/deploy";
+
+fun factorial(n: Int): Int {
+    if (n == 0) { return 1; }
+    return n * factorial(n - 1);
+}
+
+contract RecursionTester with Deployable {
+    get fun fib(n: Int): Int {
+        if (n <= 0) { return 0; }
+        if (n == 1) { return 1; }
+        return self.fib(n - 1) + self.fib(n - 2); 
+    }
+
+    get fun fact(n: Int): Int {
+        return factorial(n);
+    }
+}

tact.config.json

@@ -264,6 +264,14 @@
         "debug": true
       }
     },
+    {
+      "name": "recursion",
+      "path": "./src/test/features/recursion.tact",
+      "output": "./src/test/features/output",
+      "options": {
+        "debug": true
+      }
+    },
     {
       "name": "benchmark_functions",
       "path": "./src/benchmarks/contracts/functions.tact",