WIP on an AMM

yarn-project/end-to-end/src/e2e_amm.test.ts

@@ -0,0 +1,92 @@
+import { type AccountWallet, type DebugLogger, Fr } from '@aztec/aztec.js';
+import { AMMContract, type TokenContract } from '@aztec/noir-contracts.js';
+
+import { jest } from '@jest/globals';
+
+import { deployToken, mintTokensToPrivate } from './fixtures/token_utils.js';
+import { setup } from './fixtures/utils.js';
+
+const TIMEOUT = 120_000;
+
+// This is a very simple test checking only the happy path. More complete tests might be done in an unimaginably far
+// future (and hence irrelevant) once I return from Patagonia.
+describe('AMM', () => {
+  jest.setTimeout(TIMEOUT);
+
+  let teardown: () => Promise<void>;
+
+  let logger: DebugLogger;
+
+  let adminWallet: AccountWallet;
+  let liquidityProvider: AccountWallet;
+  let swapper: AccountWallet;
+
+  let token0: TokenContract;
+  let token1: TokenContract;
+  let liquidityToken: TokenContract;
+
+  let amm: AMMContract;
+
+  const lpBalance0 = 20000n;
+  const lpBalance1 = 10000n;
+  const swapperBalance0 = 5000n;
+
+  beforeAll(async () => {
+    let wallets: AccountWallet[];
+    ({ teardown, wallets, logger } = await setup(3));
+    [adminWallet, liquidityProvider, swapper] = wallets;
+
+    token0 = await deployToken(adminWallet, 0n, logger);
+    token1 = await deployToken(adminWallet, 0n, logger);
+    liquidityToken = await deployToken(adminWallet, 0n, logger);
+
+    amm = await AMMContract.deploy(adminWallet, token0.address, token1.address, liquidityToken.address)
+      .send()
+      .deployed();
+
+    // We mint the tokens to lp and swapper
+    await mintTokensToPrivate(token0, adminWallet, liquidityProvider.getAddress(), lpBalance0);
+    await mintTokensToPrivate(token1, adminWallet, liquidityProvider.getAddress(), lpBalance1);
+    await mintTokensToPrivate(token0, adminWallet, swapper.getAddress(), swapperBalance0);
+  });
+
+  afterAll(() => teardown());
+
+  it('full flow', async () => {
+    // ADDING LIQUIDITY
+    // Ideally we would like to deposit all the tokens from the liquidity provider
+    const amount0Desired = lpBalance0;
+    const amount1Desired = lpBalance1;
+    const amount0Min = lpBalance0 / 2n;
+    const amount1Min = lpBalance1 / 2n;
+
+    // First we need to add authwits such that the AMM can transfer the tokens from the liquidity provider
+    // The only purpose of this nonce is to make the authwit unique (function args are part of authwit hash preimage)
+    const nonceForAuthwits = Fr.random();
+
+    await liquidityProvider.createAuthWit({
+      caller: amm.address,
+      action: token0.methods.transfer_to_public(
+        liquidityProvider.getAddress(),
+        amm.address,
+        amount0Desired,
+        nonceForAuthwits,
+      ),
+    });
+    await liquidityProvider.createAuthWit({
+      caller: amm.address,
+      action: token1.methods.transfer_to_public(
+        liquidityProvider.getAddress(),
+        amm.address,
+        amount1Desired,
+        nonceForAuthwits,
+      ),
+    });
+
+    await amm
+      .withWallet(liquidityProvider)
+      .methods.add_liquidity(amount0Desired, amount1Desired, amount0Min, amount1Min, nonceForAuthwits)
+      .send()
+      .wait();
+  });
+});