use a static method that indicates it's unchecked

0xalbert · Apr 26, 2021 · c0eee21 · c0eee21
1 parent 76b9ca6
commit c0eee21
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Showing 2 changed files with 60 additions and 1 deletion.
diff --git a/src/entities/trade.test.ts b/src/entities/trade.test.ts
@@ -88,6 +88,45 @@ describe('Trade', () => {
     expect(trade.outputAmount.currency).toEqual(ETHER)
   })
 
+  describe('#createUncheckedTrade', () => {
+    it('throws if input currency does not match route', () => {
+      expect(() =>
+        Trade.createUncheckedTrade({
+          route: new Route([pool_0_1], token0),
+          inputAmount: new TokenAmount(token2, 10000),
+          outputAmount: new TokenAmount(token1, 10000),
+          tradeType: TradeType.EXACT_INPUT
+        })
+      ).toThrow('INPUT_CURRENCY_MATCH')
+    })
+    it('throws if output currency does not match route', () => {
+      expect(() =>
+        Trade.createUncheckedTrade({
+          route: new Route([pool_0_1], token0),
+          inputAmount: new TokenAmount(token0, 10000),
+          outputAmount: new TokenAmount(token2, 10000),
+          tradeType: TradeType.EXACT_INPUT
+        })
+      ).toThrow('OUTPUT_CURRENCY_MATCH')
+    })
+    it('can create an exact input trade without simulating', () => {
+      Trade.createUncheckedTrade({
+        route: new Route([pool_0_1], token0),
+        inputAmount: new TokenAmount(token0, 10000),
+        outputAmount: new TokenAmount(token1, 100000),
+        tradeType: TradeType.EXACT_INPUT
+      })
+    })
+    it('can create an exact output trade without simulating', () => {
+      Trade.createUncheckedTrade({
+        route: new Route([pool_0_1], token0),
+        inputAmount: new TokenAmount(token0, 10000),
+        outputAmount: new TokenAmount(token1, 100000),
+        tradeType: TradeType.EXACT_OUTPUT
+      })
+    })
+  })
+
   describe('#bestTradeExactIn', () => {
     it('throws with empty pools', async () => {
       await expect(Trade.bestTradeExactIn([], new TokenAmount(token0, JSBI.BigInt(10000)), token2)).rejects.toThrow(

diff --git a/src/entities/trade.ts b/src/entities/trade.ts
@@ -128,6 +128,12 @@ export class Trade {
     return Trade.fromRoute(route, amountOut, TradeType.EXACT_OUTPUT)
   }
 
+  /**
+   * Constructs a trade by simulating swaps through the given route
+   * @param route route to swap through
+   * @param amount the amount specified, either input or output, depending on tradeType
+   * @param tradeType whether the trade is an exact input or exact output swap
+   */
   public static async fromRoute(route: Route, amount: CurrencyAmount, tradeType: TradeType): Promise<Trade> {
     const amounts: TokenAmount[] = new Array(route.tokenPath.length)
     if (tradeType === TradeType.EXACT_INPUT) {
@@ -168,14 +174,28 @@ export class Trade {
     })
   }
 
+  /**
+   * Creates a trade without computing the result of swapping through the route. Useful when you have simulated the trade
+   * elsewhere and do not have any tick data
+   * @param constructorArguments the arguments passed to the trade constructor
+   */
+  public static createUncheckedTrade(constructorArguments: {
+    route: Route
+    inputAmount: CurrencyAmount
+    outputAmount: CurrencyAmount
+    tradeType: TradeType
+  }): Trade {
+    return new Trade(constructorArguments)
+  }
+
   /**
    * Construct a trade by passing in the pre-computed property values
    * @param route the route through which the trade occurs
    * @param inputAmount the amount of input paid in the trade
    * @param outputAmount the amount of output received in the trade
    * @param tradeType the type of trade, exact input or exact output
    */
-  public constructor({
+  private constructor({
     route,
     inputAmount,
     outputAmount,