Merge pull request #139 from balancer-labs/types-refactor

Strengthen type checking + general refactor of types

package.json

@@ -31,6 +31,7 @@
         "@rollup/plugin-node-resolve": "^13.0.4",
         "@rollup/plugin-typescript": "^8.2.5",
         "@types/chai": "^4.2.10",
+        "@types/lodash.clonedeep": "^4.5.6",
         "@types/mocha": "^7.0.2",
         "@types/node": "^14.0.20",
         "@typescript-eslint/eslint-plugin": "^4.29.2",

src/formatSwaps.ts

@@ -62,7 +62,7 @@ const formatSequence = (
                     ? swap.tokenInDecimals
                     : swap.tokenOutDecimals;
 
-            amountScaled = scale(bnum(swap.swapAmount), scalingFactor)
+            amountScaled = scale(bnum(swap.swapAmount as string), scalingFactor)
                 .decimalPlaces(0, 1)
                 .toString();
         }
@@ -102,10 +102,10 @@ export function formatSwaps(
 
     const { tokenInDecimals } = swaps[0].find(
         (swap) => swap.tokenIn === tokenIn
-    );
+    ) as Swap;
     const { tokenOutDecimals } = swaps[0].find(
         (swap) => swap.tokenOut === tokenOut
-    );
+    ) as Swap;
 
     const tokenArray = getTokenAddresses(swaps);
     const swapsV2: SwapV2[] = swaps.flatMap((sequence) =>

src/frontendHelpers/stableHelpers.ts

@@ -25,7 +25,7 @@ export function BPTForTokensZeroPriceImpact(
     // if there were no price impact, i.e. using the spot price of tokenIn/BPT
 
     // We need to scale down allBalances
-    const allBalancesDownScaled = [];
+    const allBalancesDownScaled: BigNumber[] = [];
     for (let i = 0; i < allBalances.length; i++) {
         allBalancesDownScaled.push(
             allBalances[i].times(new BigNumber(10).pow(-decimals[i]))

src/poolCaching/index.ts

@@ -45,7 +45,7 @@ export class PoolCacher {
                 newPools = cloneDeep(poolsData);
             } else {
                 // Retrieve from URL if set otherwise use data passed in constructor
-                if (this.isConnectedToSubgraph()) {
+                if (this.poolsUrl !== null) {
                     newPools = await fetchSubgraphPools(this.poolsUrl);
                 } else {
                     newPools = this.pools;

src/poolCaching/onchainData.ts

@@ -18,7 +18,7 @@ export async function getOnChainBalances(
 ): Promise<SubgraphPoolBase[]> {
     if (subgraphPools.length === 0) return subgraphPools;
 
-    const abis = Object.values(
+    const abis: any = Object.values(
         // Remove duplicate entries using their names
         Object.fromEntries(
             [
@@ -85,7 +85,7 @@ export async function getOnChainBalances(
         string,
         {
             amp?: string;
-            swapFee?: string;
+            swapFee: string;
             weights?: string[];
             poolTokens: {
                 tokens: string[];
@@ -111,7 +111,8 @@ export async function getOnChainBalances(
                     bnum(poolTokens.balances[i]),
                     -Number(T.decimals)
                 ).toString();
-                if (subgraphPools[poolId].poolType === 'Weighted') {
+                if (weights) {
+                    // Only expected for WeightedPools
                     T.weight = scale(bnum(weights[i]), -18).toString();
                 }
             });

src/pools/elementPool/elementPool.ts

@@ -6,6 +6,7 @@ import {
     PoolPairBase,
     SwapTypes,
     SubgraphPoolBase,
+    SubgraphToken,
 } from '../../types';
 import { getAddress } from '@ethersproject/address';
 import { bnum } from '../../utils/bignumber';
@@ -19,31 +20,16 @@ import {
     getTimeTillExpiry,
 } from './elementMath';
 
-export interface ElementPoolToken {
-    address: string;
-    balance: string;
-    decimals: string | number;
-}
+type ElementPoolToken = Pick<SubgraphToken, 'address' | 'balance' | 'decimals'>;
 
-export interface ElementPoolPairData extends PoolPairBase {
-    id: string;
-    address: string;
-    poolType: PoolTypes;
-    tokenIn: string;
-    tokenOut: string;
-    balanceIn: BigNumber;
-    balanceOut: BigNumber;
-    swapFee: BigNumber;
-    decimalsIn: number;
-    decimalsOut: number;
-    // Element specific fields
+export type ElementPoolPairData = PoolPairBase & {
     totalShares: BigNumber;
     expiryTime: number;
     unitSeconds: number;
     principalToken: string;
     baseToken: string;
     currentBlockTimestamp: number;
-}
+};
 
 export class ElementPool implements PoolBase {
     poolType: PoolTypes = PoolTypes.Element;
@@ -62,6 +48,14 @@ export class ElementPool implements PoolBase {
     currentBlockTimestamp: number;
 
     static fromPool(pool: SubgraphPoolBase): ElementPool {
+        if (!pool.expiryTime) throw new Error('ElementPool missing expiryTime');
+        if (!pool.unitSeconds)
+            throw new Error('ElementPool missing unitSeconds');
+        if (!pool.principalToken)
+            throw new Error('ElementPool missing principalToken');
+
+        if (!pool.baseToken) throw new Error('ElementPool missing baseToken');
+
         return new ElementPool(
             pool.id,
             pool.address,
@@ -196,6 +190,7 @@ export class ElementPool implements PoolBase {
         } else {
             // token is underlying in the pool
             const T = this.tokens.find((t) => t.address === token);
+            if (!T) throw Error('Pool does not contain this token');
             T.balance = newBalance.toString();
         }
     }

src/pools/index.ts

@@ -59,4 +59,5 @@ export function getOutputAmountSwap(
             return pool._tokenInForExactTokenOut(poolPairData, amount, false);
         }
     }
+    throw Error('Unsupported swap');
 }

src/pools/metaStablePool/metaStablePool.ts

@@ -3,9 +3,9 @@ import {
     PoolBase,
     PoolTypes,
     SwapPairType,
-    PoolPairBase,
     SwapTypes,
     SubgraphPoolBase,
+    SubgraphToken,
 } from '../../types';
 import { getAddress } from '@ethersproject/address';
 import { bnum, scale, ZERO } from '../../utils/bignumber';
@@ -17,35 +17,17 @@ import {
     _derivativeSpotPriceAfterSwapExactTokenInForTokenOut,
     _derivativeSpotPriceAfterSwapTokenInForExactTokenOut,
 } from './metaStableMath';
+import { StablePoolPairData } from 'pools/stablePool/stablePool';
 
-export interface MetaStablePoolToken {
-    address: string;
-    balance: string;
-    decimals: string | number;
-    priceRate?: string;
-}
+type MetaStablePoolToken = Pick<
+    SubgraphToken,
+    'address' | 'balance' | 'decimals' | 'priceRate'
+>;
 
-export interface MetaStablePoolPairData extends PoolPairBase {
-    id: string;
-    address: string;
-    poolType: PoolTypes;
-    tokenIn: string;
-    tokenOut: string;
-    balanceIn: BigNumber;
-    balanceOut: BigNumber;
-    swapFee: BigNumber;
-    swapFeeScaled: BigNumber;
-    decimalsIn: number;
-    decimalsOut: number;
-    allBalances: BigNumber[]; // Only for stable pools
-    allBalancesScaled: BigNumber[]; // Only for stable pools - EVM Maths uses everything in 1e18 upscaled format and this avoids repeated scaling
-    invariant: BigNumber; // Only for stable pools
-    amp: BigNumber; // Only for stable pools
-    tokenIndexIn: number; // Only for stable pools
-    tokenIndexOut: number; // Only for stable pools
+export type MetaStablePoolPairData = StablePoolPairData & {
     tokenInPriceRate: BigNumber;
     tokenOutPriceRate: BigNumber;
-}
+};
 
 export class MetaStablePool implements PoolBase {
     poolType: PoolTypes = PoolTypes.MetaStable;
@@ -195,6 +177,7 @@ export class MetaStablePool implements PoolBase {
         } else {
             // token is underlying in the pool
             const T = this.tokens.find((t) => t.address === token);
+            if (!T) throw Error('Pool does not contain this token');
             T.balance = newBalance.toString();
         }
     }

src/pools/stablePool/stablePool.ts

@@ -6,6 +6,7 @@ import {
     PoolPairBase,
     SwapTypes,
     SubgraphPoolBase,
+    SubgraphToken,
 } from '../../types';
 import { getAddress } from '@ethersproject/address';
 import { bnum, scale, ZERO } from '../../utils/bignumber';
@@ -18,31 +19,17 @@ import {
     _derivativeSpotPriceAfterSwapTokenInForExactTokenOut,
 } from './stableMath';
 
-export interface StablePoolToken {
-    address: string;
-    balance: string;
-    decimals: string | number;
-}
+type StablePoolToken = Pick<SubgraphToken, 'address' | 'balance' | 'decimals'>;
 
-export interface StablePoolPairData extends PoolPairBase {
-    id: string;
-    address: string;
-    poolType: PoolTypes;
-    tokenIn: string;
-    tokenOut: string;
-    balanceIn: BigNumber;
-    balanceOut: BigNumber;
-    swapFee: BigNumber;
-    swapFeeScaled: BigNumber;
-    decimalsIn: number;
-    decimalsOut: number;
-    allBalances: BigNumber[]; // Only for stable pools
-    allBalancesScaled: BigNumber[]; // Only for stable pools - EVM Maths uses everything in 1e18 upscaled format and this avoids repeated scaling
-    invariant: BigNumber; // Only for stable pools
-    amp: BigNumber; // Only for stable pools
-    tokenIndexIn: number; // Only for stable pools
-    tokenIndexOut: number; // Only for stable pools
-}
+export type StablePoolPairData = PoolPairBase & {
+    swapFeeScaled: BigNumber; // EVM Maths uses everything in 1e18 upscaled format and this avoids repeated scaling
+    allBalances: BigNumber[];
+    allBalancesScaled: BigNumber[]; // EVM Maths uses everything in 1e18 upscaled format and this avoids repeated scaling
+    invariant: BigNumber;
+    amp: BigNumber;
+    tokenIndexIn: number;
+    tokenIndexOut: number;
+};
 
 export class StablePool implements PoolBase {
     poolType: PoolTypes = PoolTypes.Stable;
@@ -175,6 +162,7 @@ export class StablePool implements PoolBase {
         } else {
             // token is underlying in the pool
             const T = this.tokens.find((t) => t.address === token);
+            if (!T) throw Error('Pool does not contain this token');
             T.balance = newBalance.toString();
         }
     }

src/pools/weightedPool/weightedPool.ts

@@ -1,5 +1,5 @@
 import { getAddress } from '@ethersproject/address';
-import { bnum, scale, ZERO, ONE } from '../../utils/bignumber';
+import { bnum, scale, ZERO } from '../../utils/bignumber';
 import { BigNumber } from '../../utils/bignumber';
 import * as SDK from '@georgeroman/balancer-v2-pools';
 import {
@@ -9,6 +9,8 @@ import {
     PoolPairBase,
     SwapTypes,
     SubgraphPoolBase,
+    SubgraphToken,
+    NoNullableField,
 } from '../../types';
 import {
     _exactTokenInForTokenOut,
@@ -19,27 +21,15 @@ import {
     _derivativeSpotPriceAfterSwapTokenInForExactTokenOut,
 } from './weightedMath';
 
-export interface WeightedPoolToken {
-    address: string;
-    balance: string;
-    decimals: string | number;
-    weight?: string;
-}
+export type WeightedPoolToken = Pick<
+    NoNullableField<SubgraphToken>,
+    'address' | 'balance' | 'decimals' | 'weight'
+>;
 
-export interface WeightedPoolPairData extends PoolPairBase {
-    id: string;
-    address: string;
-    poolType: PoolTypes;
-    tokenIn: string;
-    tokenOut: string;
-    balanceIn: BigNumber;
-    balanceOut: BigNumber;
-    weightIn: BigNumber; // Weights are only defined for weighted pools
-    weightOut: BigNumber; // Weights are only defined for weighted pools
-    swapFee: BigNumber;
-    decimalsIn: number;
-    decimalsOut: number;
-}
+export type WeightedPoolPairData = PoolPairBase & {
+    weightIn: BigNumber;
+    weightOut: BigNumber;
+};
 
 export class WeightedPool implements PoolBase {
     poolType: PoolTypes = PoolTypes.Weighted;
@@ -63,7 +53,7 @@ export class WeightedPool implements PoolBase {
             pool.swapFee,
             pool.totalWeight,
             pool.totalShares,
-            pool.tokens,
+            pool.tokens as WeightedPoolToken[],
             pool.tokensList
         );
     }
@@ -86,7 +76,7 @@ export class WeightedPool implements PoolBase {
         this.totalWeight = bnum(totalWeight);
     }
 
-    setTypeForSwap(type: SwapPairType) {
+    setTypeForSwap(type: SwapPairType): void {
         this.swapPairType = type;
     }
 
@@ -131,7 +121,7 @@ export class WeightedPool implements PoolBase {
     // inverse of the slippage. It is proportional to the token balances in the
     // pool but also depends on the shape of the invariant curve.
     // As a standard, we define normalized liquidity in tokenOut
-    getNormalizedLiquidity(poolPairData: WeightedPoolPairData) {
+    getNormalizedLiquidity(poolPairData: WeightedPoolPairData): BigNumber {
         return poolPairData.balanceOut
             .times(poolPairData.weightIn)
             .div(poolPairData.weightIn.plus(poolPairData.weightOut));
@@ -156,6 +146,7 @@ export class WeightedPool implements PoolBase {
         } else {
             // token is underlying in the pool
             const T = this.tokens.find((t) => t.address === token);
+            if (!T) throw Error('Pool does not contain this token');
             T.balance = newBalance.toString();
         }
     }