js: add allocate test

clients/js/test/allocate.test.ts

@@ -0,0 +1,60 @@
+import {
+    appendTransactionMessageInstruction,
+    fetchEncodedAccount,
+    generateKeyPairSigner,
+    pipe,
+    airdropFactory,
+    lamports,
+} from '@solana/kit';
+import { it, expect } from 'vitest';
+import { getAllocateInstruction } from '../src';
+import {
+    createDefaultSolanaClient,
+    createDefaultTransaction,
+    generateKeyPairSignerWithSol,
+    signAndSendTransaction,
+} from './_setup';
+
+it('allocates space for an account', async () => {
+    // 1. Setup client and payer.
+    const client = createDefaultSolanaClient();
+    const [payer, accountToAllocate] = await Promise.all([
+        generateKeyPairSignerWithSol(client),
+        generateKeyPairSigner(),
+    ]);
+
+    // 2. Airdrop lamports to the account so it exists (system owned, 0 data).
+    await airdropFactory(client)({
+        recipientAddress: accountToAllocate.address,
+        lamports: lamports(await client.rpc.getMinimumBalanceForRentExemption(100n).send()),
+        commitment: 'confirmed',
+    });
+
+    // Verify initial state
+    let fetchedAccount = await fetchEncodedAccount(client.rpc, accountToAllocate.address);
+    expect(fetchedAccount.exists).toBe(true);
+    if (fetchedAccount.exists) {
+        expect(fetchedAccount.data.length).toBe(0);
+    }
+
+    // 3. Use getAllocateInstruction to allocate 100 bytes.
+    const newSpace = 100n;
+    const allocate = getAllocateInstruction({
+        newAccount: accountToAllocate,
+        space: newSpace,
+    });
+
+    // 4. Send transaction
+    await pipe(
+        await createDefaultTransaction(client, payer),
+        tx => appendTransactionMessageInstruction(allocate, tx),
+        tx => signAndSendTransaction(client, tx),
+    );
+
+    // 5. Verify the account's data length is exactly 100 bytes.
+    fetchedAccount = await fetchEncodedAccount(client.rpc, accountToAllocate.address);
+    expect(fetchedAccount.exists).toBe(true);
+    if (fetchedAccount.exists) {
+        expect(fetchedAccount.data.length).toBe(100);
+    }
+});