Refactor TokenAdjacency and TokenAdjacencyBuilder [TKR-324] (#517)

* Add a new TokenAdjacencyGraph implementation

* Replace old TokenAdjacencyGraph with new implementation

* Simplify token adjacency graph in constants.ts

* Fix lint error

* Update CHANGELOG.json

packages/asset-swapper/test/dex_sampler_test.ts

@@ -13,7 +13,8 @@ import * as _ from 'lodash';
 
 import { SignedOrder } from '../src/types';
 import { DexOrderSampler, getSampleAmounts } from '../src/utils/market_operation_utils/sampler';
-import { ERC20BridgeSource, TokenAdjacencyGraph } from '../src/utils/market_operation_utils/types';
+import { ERC20BridgeSource } from '../src/utils/market_operation_utils/types';
+import { TokenAdjacencyGraphBuilder } from '../src/utils/token_adjacency_graph';
 
 import { MockSamplerContract } from './utils/mock_sampler_contract';
 import { generatePseudoRandomSalt } from './utils/utils';
@@ -29,7 +30,7 @@ describe('DexSampler tests', () => {
     const wethAddress = getContractAddressesForChainOrThrow(CHAIN_ID).etherToken;
     const exchangeProxyAddress = getContractAddressesForChainOrThrow(CHAIN_ID).exchangeProxy;
 
-    const tokenAdjacencyGraph: TokenAdjacencyGraph = { default: [wethAddress] };
+    const tokenAdjacencyGraph = new TokenAdjacencyGraphBuilder([wethAddress]).build();
 
     describe('getSampleAmounts()', () => {
         const FILL_AMOUNT = getRandomInteger(1, 1e18);

packages/asset-swapper/test/market_operation_utils_test.ts

@@ -15,7 +15,7 @@ import { Pool } from 'balancer-labs-sor-v1/dist/types';
 import * as _ from 'lodash';
 import * as TypeMoq from 'typemoq';
 
-import { MarketOperation, QuoteRequestor, RfqRequestOpts, SignedNativeOrder } from '../src';
+import { MarketOperation, QuoteRequestor, RfqRequestOpts, SignedNativeOrder, TokenAdjacencyGraph } from '../src';
 import { Integrator } from '../src/types';
 import { MarketOperationUtils } from '../src/utils/market_operation_utils/';
 import {
@@ -39,7 +39,6 @@ import {
     MarketSideLiquidity,
     OptimizedMarketBridgeOrder,
     OptimizerResultWithReport,
-    TokenAdjacencyGraph,
 } from '../src/utils/market_operation_utils/types';
 
 const MAKER_TOKEN = randomAddress();
@@ -57,7 +56,7 @@ const DEFAULT_EXCLUDED = SELL_SOURCE_FILTER_BY_CHAIN_ID[ChainId.Mainnet].sources
 );
 const BUY_SOURCES = BUY_SOURCE_FILTER_BY_CHAIN_ID[ChainId.Mainnet].sources;
 const SELL_SOURCES = SELL_SOURCE_FILTER_BY_CHAIN_ID[ChainId.Mainnet].sources;
-const TOKEN_ADJACENCY_GRAPH: TokenAdjacencyGraph = { default: [] };
+const TOKEN_ADJACENCY_GRAPH = TokenAdjacencyGraph.getEmptyGraph();
 
 const SIGNATURE = { v: 1, r: NULL_BYTES, s: NULL_BYTES, signatureType: SignatureType.EthSign };
 const FOO_INTEGRATOR: Integrator = {

packages/asset-swapper/test/token_adjacency_graph_test.ts

@@ -0,0 +1,108 @@
+import * as chai from 'chai';
+import 'mocha';
+
+import { TokenAdjacencyGraphBuilder } from '../src/utils/token_adjacency_graph';
+
+import { chaiSetup } from './utils/chai_setup';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('TokenAdjacencyGraphBuilder and TokenAdjacencyGraph', () => {
+    describe('constructor', () => {
+        it('sanitizes passed default tokens to lower case', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['DEFAULT_1', 'DEFAULT_2']).build();
+
+            expect(graph.getAdjacentTokens('random_token')).to.deep.eq(['default_1', 'default_2']);
+        });
+    });
+
+    describe('add', () => {
+        it('adds a new token path to the graph', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1', 'default_2']).add('token_a', 'token_b').build();
+
+            expect(graph.getAdjacentTokens('token_a')).to.deep.eq(['default_1', 'default_2', 'token_b']);
+        });
+
+        it('adds lower-cased token path to the graph', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1', 'default_2']).add('TOKEN_A', 'TOKEN_B').build();
+
+            expect(graph.getAdjacentTokens('token_a')).to.deep.eq(['default_1', 'default_2', 'token_b']);
+        });
+
+        it('ignores an existing to token', async () => {
+            const graph = new TokenAdjacencyGraphBuilder()
+                .add('token_a', 'token_b')
+                .add('token_a', 'token_b')
+                .build();
+
+            expect(graph.getAdjacentTokens('token_a')).to.deep.eq(['token_b']);
+        });
+    });
+
+    describe('addBidirectional', () => {
+        it('adds a bidirectional path to the graph', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1']).addBidirectional('token_a', 'token_b').build();
+
+            expect(graph.getAdjacentTokens('token_a')).to.deep.eq(['default_1', 'token_b']);
+            expect(graph.getAdjacentTokens('token_b')).to.deep.eq(['default_1', 'token_a']);
+        });
+    });
+
+    describe('addCompleteSubgraph', () => {
+        it('adds a complete subgraph to the graph', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1'])
+                .addCompleteSubgraph(['token_a', 'token_b', 'token_c', 'token_d'])
+                .build();
+
+            expect(graph.getAdjacentTokens('token_a')).to.deep.eq(['default_1', 'token_b', 'token_c', 'token_d']);
+            expect(graph.getAdjacentTokens('token_b')).to.deep.eq(['default_1', 'token_a', 'token_c', 'token_d']);
+            expect(graph.getAdjacentTokens('token_c')).to.deep.eq(['default_1', 'token_a', 'token_b', 'token_d']);
+            expect(graph.getAdjacentTokens('token_d')).to.deep.eq(['default_1', 'token_a', 'token_b', 'token_c']);
+        });
+    });
+
+    describe('tap', () => {
+        it('applies callback correctly', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1'])
+                .tap(g => {
+                    g.add('token_a', 'token_b');
+                    g.add('token_c', 'token_d');
+                })
+                .build();
+
+            expect(graph.getAdjacentTokens('token_a')).to.deep.eq(['default_1', 'token_b']);
+            expect(graph.getAdjacentTokens('token_c')).to.deep.eq(['default_1', 'token_d']);
+        });
+    });
+
+    describe('getIntermediateTokens', () => {
+        it('returns intermediate tokens without a duplicate ', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1'])
+                .add('token_a', 'token_b')
+                .add('token_c', 'token_b')
+                .build();
+
+            expect(graph.getIntermediateTokens('token_a', 'token_c')).to.deep.eq(['default_1', 'token_b']);
+        });
+
+        it('returns intermediate tokens after lower-casing taker and maker tokens', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1'])
+                .add('token_a', 'token_b')
+                .add('token_c', 'token_d')
+                .build();
+
+            expect(graph.getIntermediateTokens('TOKEN_a', 'token_C')).to.deep.eq(['default_1', 'token_b', 'token_d']);
+        });
+
+        it('returns intermediate tokens excluding taker token or maker token ', async () => {
+            const graph = new TokenAdjacencyGraphBuilder(['default_1'])
+                .addBidirectional('token_a', 'token_b')
+                .addBidirectional('token_b', 'token_c')
+                .addBidirectional('token_c', 'token_a')
+                .build();
+
+            expect(graph.getIntermediateTokens('token_a', 'token_c')).to.deep.eq(['default_1', 'token_b']);
+        });
+    });
+});