feat: hook_pos (#31)

Author: 9oelM

hooks-rs/examples/hook_pos.rs

@@ -0,0 +1,18 @@
+#![no_std]
+#![no_main]
+
+use hooks_rs::*;
+
+#[no_mangle]
+pub extern "C" fn cbak(_: u32) -> i64 {
+    0
+}
+
+#[no_mangle]
+pub extern "C" fn hook(_: u32) -> i64 {
+    max_iter(1);
+
+    let hook_pos = hook_pos();
+
+    accept(b"", hook_pos);
+}

hooks-rs/src/api/hook.rs

@@ -57,3 +57,16 @@ pub fn hook_param<const HOOK_PARAM_LEN: usize>(
 
     init_buffer_mut(func)
 }
+
+/// Returns the position in the hook chain the currently executing hook occupies.
+/// Returns the position in the chain the currently executing hook occupies. The first position is 0.
+///
+/// # Example
+/// ```
+/// // hook_pos is 0 for the first hook in the chain
+/// let hook_pos = hook_pos();
+/// ```
+#[inline(always)]
+pub fn hook_pos() -> i64 {
+    unsafe { c::hook_pos() }
+}

hooks-rs/tests/hook_pos.test.ts

@@ -0,0 +1,87 @@
+// xrpl
+import { Client, Invoke, Transaction, Wallet } from "@transia/xrpl";
+import { TestUtils } from "./setup";
+import { HookExecution } from "@transia/xrpl/dist/npm/models/transactions/metadata";
+
+const HOOK_NAME = "hook_pos";
+
+describe("hook_pos.rs", () => {
+  let client: Client;
+  let alice: Wallet;
+  let bob: Wallet;
+
+  beforeAll(async () => {
+    const hook = await TestUtils.buildHook(HOOK_NAME);
+    client = new Client("wss://xahau-test.net", {});
+    await client.connect();
+    client.networkID = await client.getNetworkID();
+    // Because Faucet only allows one account to be created every 60 seconds,
+    // we will use the following accounts for testing. Change the secrets when
+    // running out of funds.
+    // rLuT6H5sRaANwzphL3vLxD3cM3uDEhjs4J
+    alice = Wallet.fromSecret(`shEqcVgyFdo5ARiFXhhBLmtg37mgp`);
+    // rJVeCKt982a2n33SsnQfM2EdurTsGN8Hhz
+    bob = Wallet.fromSecret(`ssh8Y2q2EeFDTLNS6m5BPhYGExxqb`);
+    await TestUtils.setHook(client, alice.seed!, hook);
+  }, 3 * 60_000);
+
+  afterAll(async () => {
+    await client.disconnect();
+  }, 10_000);
+
+  it(
+    "accepts with the hook pos which is 0",
+    async () => {
+      const tx: Invoke & Transaction = {
+        TransactionType: "Invoke",
+        Account: bob.classicAddress,
+        Destination: alice.classicAddress,
+      };
+      // Autofilling fee does not work with hooks yet
+      const { Fee, ...rest } = await client.autofill(tx);
+      const fee = await TestUtils.getTransactionFee(client, rest);
+      const txResponse = await TestUtils.submitAndWaitWithRetries(
+        client,
+        {
+          ...tx,
+          Fee: fee,
+        },
+        {
+          wallet: bob,
+          autofill: true,
+        },
+      );
+      if (!txResponse.result.meta) {
+        throw new Error("No meta in tx response");
+      }
+      if (typeof txResponse.result.meta === "string") {
+        throw new Error("Meta is string, not object");
+      }
+
+      const { meta } = txResponse.result;
+      if (!(meta.HookExecutions && meta.HookExecutions.length > 0)) {
+        throw new Error(`Hook execution data is empty`);
+      }
+
+      if (meta.HookExecutions.length > 1) {
+        throw new Error(`Hook execution happened more than once`);
+      }
+
+      if (txResponse.result.meta.TransactionResult !== "tesSUCCESS") {
+        console.error(JSON.stringify(txResponse, null, 2));
+
+        throw new Error(`Transaction failed`);
+      }
+
+      // safe type: we checked everything
+      const [hookExecution] = meta.HookExecutions as [HookExecution];
+
+      const { HookReturnString, HookReturnCode } = hookExecution.HookExecution;
+
+      expect(HookReturnString).toMatch("");
+      // HookPos should be 0
+      expect(Number(HookReturnCode)).toBe(0);
+    },
+    3 * 60_000,
+  );
+});