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packages/0x.js/test/utils/token_utils.ts

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+import * as _ from 'lodash';
+import {Token, InternalZeroExError} from '../../src/types';
+
+const PROTOCOL_TOKEN_SYMBOL = 'ZRX';
+
+export class TokenUtils {
+    private tokens: Token[];
+    constructor(tokens: Token[]) {
+        this.tokens = tokens;
+    }
+    public getProtocolTokenOrThrow(): Token {
+        const zrxToken = _.find(this.tokens, {symbol: PROTOCOL_TOKEN_SYMBOL});
+        if (_.isUndefined(zrxToken)) {
+            throw new Error(InternalZeroExError.ZrxNotInTokenRegistry);
+        }
+        return zrxToken;
+    }
+    public getNonProtocolTokens(): Token[] {
+        const nonProtocolTokens = _.filter(this.tokens, token => {
+            return token.symbol !== PROTOCOL_TOKEN_SYMBOL;
+        });
+        return nonProtocolTokens;
+    }
+}