refactor: remove setting of total swap costs

balancer · Aug 25, 2021 · b1b6eab · b1b6eab
1 parent b8d7a7e
commit b1b6eab
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Showing 4 changed files with 19 additions and 54 deletions.
diff --git a/src/swapCostCalculator.ts b/src/swapCostCalculator.ts
@@ -18,14 +18,12 @@ export class SwapCostCalculator {
     private tokenPriceCache: Record<string, string> = {
         ZERO_ADDRESS: BONE.toString(),
     };
-    private swapCostOverride: Record<string, string> = {};
 
     private initializeCache(): void {
         this.tokenPriceCache = {
             ZERO_ADDRESS: BONE.toString(),
             [WETHADDR[this.chainId].toLowerCase()]: BONE.toString(),
         };
-        this.swapCostOverride = {};
     }
 
     constructor(chainId: number) {
@@ -82,14 +80,6 @@ export class SwapCostCalculator {
         this.tokenPriceCache[tokenAddress.toLowerCase()] = tokenPrice;
     }
 
-    /**
-     * We only include this function as a hack as the tests expect to be able to set the swap fee directly
-     * @deprecated Use `setNativeAssetPriceInToken`
-     */
-    setSwapCostOverride(tokenAddress: string, swapCost: string): void {
-        this.swapCostOverride[tokenAddress.toLowerCase()] = swapCost;
-    }
-
     /**
      * Calculate the cost of spending a certain amount of gas in terms of a token.
      * This allows us to determine whether an increased amount of tokens gained
@@ -106,9 +96,6 @@ export class SwapCostCalculator {
         gasPriceWei: BigNumber,
         swapGasCost: BigNumber
     ): Promise<BigNumber> {
-        if (this.swapCostOverride[tokenAddress.toLowerCase()]) {
-            return bnum(this.swapCostOverride[tokenAddress.toLowerCase()]);
-        }
         return calculateTotalSwapCost(
             await this.getNativeAssetPriceInToken(tokenAddress, tokenDecimals),
             swapGasCost,

diff --git a/src/wrapper.ts b/src/wrapper.ts
@@ -54,7 +54,7 @@ export class SOR {
     disabledOptions: DisabledOptions;
 
     private poolCacher: PoolCacher;
-    private swapCostCalculator: SwapCostCalculator;
+    swapCostCalculator: SwapCostCalculator;
 
     constructor(
         provider: BaseProvider,
@@ -94,29 +94,6 @@ export class SOR {
         );
     }
 
-    /*
-    Find and cache cost of token.
-    If cost is passed then it manually sets the value.
-    */
-    async setCostOutputToken(
-        tokenOut: string,
-        tokenDecimals: number,
-        cost: BigNumber = null
-    ): Promise<BigNumber> {
-        if (cost !== null) {
-            this.swapCostCalculator.setSwapCostOverride(
-                tokenOut,
-                cost.toString()
-            );
-        }
-        return this.swapCostCalculator.convertGasCostToToken(
-            tokenOut,
-            tokenDecimals,
-            this.gasPrice,
-            this.swapCost
-        );
-    }
-
     /*
     Saves updated pools data to internal onChainBalanceCache.
     If isOnChain is true will retrieve all required onChain data. (false is advised to only be used for testing)

diff --git a/test/lib/testHelpers.ts b/test/lib/testHelpers.ts
@@ -14,7 +14,7 @@ import {
     PoolFilter,
     SwapV2,
 } from '../../src/types';
-import { bnum } from '../../src/utils/bignumber';
+import { bnum, BONE } from '../../src/utils/bignumber';
 import * as fs from 'fs';
 import { assert } from 'chai';
 import { getAddress } from '@ethersproject/address';
@@ -360,18 +360,23 @@ export async function getFullSwap(
 
     let swapTypeCorrect = SwapTypes.SwapExactIn;
 
+    // We're wanting to set the value of costOutputToken so we calculate
+    // a native asset price which will give the desired value
+    const effectiveNativeAssetPrice = costOutputToken
+        .div(gasPrice)
+        .div(swapCost)
+        .div(BONE)
+        .toString();
     if (swapType === 'swapExactIn')
-        await sor.setCostOutputToken(
+        await sor.swapCostCalculator.setNativeAssetPriceInToken(
             tokenOut,
-            returnAmountDecimals,
-            costOutputToken
+            effectiveNativeAssetPrice
         );
     else {
         swapTypeCorrect = SwapTypes.SwapExactOut;
-        await sor.setCostOutputToken(
+        await sor.swapCostCalculator.setNativeAssetPriceInToken(
             tokenIn,
-            returnAmountDecimals,
-            costOutputToken
+            effectiveNativeAssetPrice
         );
     }
 

diff --git a/test/testScripts/swapExample.ts b/test/testScripts/swapExample.ts
@@ -192,17 +192,13 @@ async function getSwap(
     const sor = new SOR(provider, gasPrice, maxNoPools, networkId, poolsSource);
 
     // This calculates the cost to make a swap which is used as an input to sor to allow it to make gas efficient recommendations.
-    // Can be set once and will be used for further swap calculations.
-    // Defaults to 0 if not called or can be set manually using: await sor.setCostOutputToken(tokenOut, manualPriceBn)
     // Note - tokenOut for SwapExactIn, tokenIn for SwapExactOut
-    let cost: BigNumber;
-    if (swapType === SwapTypes.SwapExactOut)
-        cost = await sor.setCostOutputToken(tokenIn.address, tokenIn.decimals);
-    else
-        cost = await sor.setCostOutputToken(
-            tokenOut.address,
-            tokenOut.decimals
-        );
+    const outputToken =
+        swapType === SwapTypes.SwapExactOut ? tokenIn : tokenOut;
+    const cost = await sor.getCostOutputToken(
+        outputToken.address,
+        outputToken.decimals
+    );
 
     // Will get onChain data for pools list
     await sor.fetchPools(queryOnChain);