quoter doc

src/keywords.json

@@ -8,6 +8,15 @@
     "trade",
     "swapping"
   ],
+  "/quoter": [
+    "quoter",
+    "quoting",
+    "exact input",
+    "exact output",
+    "single",
+    "multi",
+    "multihop"
+  ],
   "/initialize": [
     "pool",
     "initialize",

src/pages/quoter/Quoter.sol

@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+import "forge-std/Test.sol";
+import {IHooks} from "v4-core/interfaces/IHooks.sol";
+import {Hooks} from "v4-core/libraries/Hooks.sol";
+import {TickMath} from "v4-core/libraries/TickMath.sol";
+import {IPoolManager} from "v4-core/interfaces/IPoolManager.sol";
+import {PoolKey} from "v4-core/types/PoolKey.sol";
+import {BalanceDelta} from "v4-core/types/BalanceDelta.sol";
+import {PoolId, PoolIdLibrary} from "v4-core/types/PoolId.sol";
+import {Constants} from "v4-core/../test/utils/Constants.sol";
+import {CurrencyLibrary, Currency} from "v4-core/types/Currency.sol";
+import {HookTest} from "@v4-by-example/utils/HookTest.sol";
+import {IQuoter} from "v4-periphery/interfaces/IQuoter.sol";
+import {Quoter} from "v4-periphery/lens/Quoter.sol";
+
+contract QuoterTest is HookTest {
+    using PoolIdLibrary for PoolKey;
+    using CurrencyLibrary for Currency;
+
+    PoolKey poolKey;
+    PoolId poolId;
+    Quoter quoter;
+
+    function setUp() public {
+        // creates the pool manager, test tokens, and other utility routers
+        HookTest.initHookTestEnv();
+        quoter = new Quoter(address(manager));
+
+        // Create the pool
+        poolKey =
+            PoolKey(Currency.wrap(address(token0)), Currency.wrap(address(token1)), 3000, 60, IHooks(address(0x0)));
+        poolId = poolKey.toId();
+        initializeRouter.initialize(poolKey, Constants.SQRT_RATIO_1_1, ZERO_BYTES);
+
+        // Provide liquidity to the pool
+        modifyPositionRouter.modifyLiquidity(
+            poolKey,
+            IPoolManager.ModifyLiquidityParams(TickMath.minUsableTick(60), TickMath.maxUsableTick(60), 1000 ether),
+            ZERO_BYTES
+        );
+    }
+
+    function testQuoter_output() public {
+        uint128 amountIn = 1e18;
+        bool zeroForOne = true;
+        uint160 MAX_SLIPPAGE = zeroForOne ? MIN_PRICE_LIMIT : MAX_PRICE_LIMIT;
+
+        // get the quote
+        PoolKey memory key = poolKey;
+        (int128[] memory deltaAmounts, uint160 sqrtPriceX96After,) = quoter.quoteExactInputSingle(
+            IQuoter.QuoteExactSingleParams(key, zeroForOne, address(this), amountIn, MAX_SLIPPAGE, ZERO_BYTES)
+        );
+
+        // output is amount 1
+        int128 outputAmount = deltaAmounts[1];
+        console2.log("Quoted output amount: ", int256(outputAmount));
+
+        // Perform a test swap
+        BalanceDelta swapDelta = swap(poolKey, int256(uint256(amountIn)), zeroForOne, ZERO_BYTES);
+
+        // quote agrees with the actual swap
+        assertEq(outputAmount, swapDelta.amount1());
+    }
+
+    function testQuoter_input() public {
+        uint128 amountOut = 1e18;
+        bool zeroForOne = true;
+        uint160 MAX_SLIPPAGE = zeroForOne ? MIN_PRICE_LIMIT : MAX_PRICE_LIMIT;
+
+        // get the quote
+        PoolKey memory key = poolKey;
+        (int128[] memory deltaAmounts, uint160 sqrtPriceX96After,) = quoter.quoteExactOutputSingle(
+            IQuoter.QuoteExactSingleParams(key, zeroForOne, address(this), amountOut, MAX_SLIPPAGE, ZERO_BYTES)
+        );
+
+        // input (quoted) is amount 0
+        int128 inputAmount = deltaAmounts[0];
+        console2.log("Quoted input amount: ", int256(inputAmount));
+
+        // Perform a exact-output swap
+        BalanceDelta swapDelta = swap(poolKey, -int256(uint256(amountOut)), zeroForOne, ZERO_BYTES);
+        assertEq(inputAmount, swapDelta.amount0());
+        (uint160 sqrtPriceX96,,) = manager.getSlot0(poolId);
+        assertEq(sqrtPriceX96After, sqrtPriceX96);
+    }
+}

src/pages/quoter/QuoterSnippet.solsnippet

@@ -0,0 +1,13 @@
+import {IQuoter} from "v4-periphery/interfaces/IQuoter.sol";
+
+PoolKey memory key;
+uint128 amountIn = 1e18;
+bool zeroForOne = true;
+uint160 MAX_SLIPPAGE = zeroForOne ? MIN_PRICE_LIMIT : MAX_PRICE_LIMIT;
+bytes memory hookData;
+
+// exact input will quote deltaAmounts[1] (output)
+// exact output will quote deltaAmounts[0] (input)
+(int128[] memory deltaAmounts, uint160 sqrtPriceX96After,) = quoter.quoteExactInputSingle(
+    IQuoter.QuoteExactSingleParams(key, zeroForOne, address(this), amountIn, MAX_SLIPPAGE, hookData)
+);