ABI Encoding for all combinations of arrays

3 files changed, 1501 insertions, 1291 deletions

diff --git a/packages/order-utils/test/abi_encoder.ts b/packages/order-utils/test/abi_encoder.ts
new file mode 100644
index 000000000..55b63b701
--- /dev/null
+++ b/packages/order-utils/test/abi_encoder.ts
@@ -0,0 +1,1098 @@
+
+import * as chai from 'chai';
+import 'mocha';
+import ethUtil = require('ethereumjs-util');
+
+var _ = require('lodash');
+
+import { chaiSetup } from './utils/chai_setup';
+
+import { MethodAbi, DataItem } from 'ethereum-types';
+
+import { BigNumber } from '@0x/utils';
+import { bigNumberify } from 'ethers/utils';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+
+class Word {
+    private value: string;
+
+    constructor(value?: string) {
+        if (value === undefined) {
+            this.value = '';
+        } else {
+            this.value = value;
+        }
+    }
+
+    public set(value: string) {
+        if (value.length !== 64) {
+            throw `Tried to create word that is not 32 bytes: ${value}`;
+        }
+
+        this.value = value;
+    }
+
+    public get(): string {
+        return this.value;
+    }
+
+    public getAsHex(): string {
+        return `0x${this.value}`;
+    }
+}
+
+export enum CalldataSection {
+    NONE,
+    PARAMS,
+    DATA,
+}
+
+class Memblock {
+    private dataType: DataType;
+    private location: { calldataSection: CalldataSection; sectionOffset: BigNumber; offset: BigNumber };
+
+    constructor(dataType: DataType) {
+        this.dataType = dataType;
+        this.location = {
+            calldataSection: CalldataSection.NONE,
+            sectionOffset: new BigNumber(0),
+            offset: new BigNumber(0),
+        };
+    }
+
+    public getSize(): BigNumber {
+        return new BigNumber(ethUtil.toBuffer(this.dataType.getHexValue()).byteLength);
+    }
+
+    public assignLocation(calldataSection: CalldataSection, sectionOffset: BigNumber, offset: BigNumber) {
+        this.location.calldataSection = calldataSection;
+        this.location.sectionOffset = sectionOffset;
+        this.location.offset = offset;
+    }
+
+    public get(): string {
+        return ethUtil.stripHexPrefix(this.dataType.getHexValue());
+    }
+
+    public getOffset(): BigNumber {
+        return this.location.offset;
+    }
+
+    public getAbsoluteOffset(): BigNumber {
+        return this.location.sectionOffset.plus(this.location.offset);
+    }
+
+    public getSection(): CalldataSection {
+        return this.location.calldataSection;
+    }
+}
+
+interface BindList {
+    [key: string]: Memblock;
+}
+
+export class Calldata {
+    private selector: string;
+    private params: Memblock[];
+    private data: Memblock[];
+    private dataOffset: BigNumber;
+    private currentDataOffset: BigNumber;
+    private currentParamOffset: BigNumber;
+    private bindList: BindList;
+
+    constructor(selector: string, nParams: number) {
+        this.selector = selector;
+        this.params = [];
+        this.data = [];
+        const evmWordSize = 32;
+        this.dataOffset = new BigNumber(nParams).times(evmWordSize);
+        this.currentDataOffset = new BigNumber(0);
+        this.currentParamOffset = new BigNumber(0);
+        this.bindList = {};
+    }
+
+    public bind(dataType: DataType, section: CalldataSection) {
+        if (dataType.getId() in this.bindList) {
+            throw `Rebind on ${dataType.getId()}`;
+        }
+        const memblock = new Memblock(dataType);
+        switch (section) {
+            case CalldataSection.PARAMS:
+                this.params.push(memblock);
+                memblock.assignLocation(section, new BigNumber(0), this.currentParamOffset);
+
+                console.log(`Binding ${dataType.getDataItem().name} to PARAMS at ${this.currentParamOffset}`);
+                this.currentParamOffset = this.currentParamOffset.plus(memblock.getSize());
+                break;
+
+            case CalldataSection.DATA:
+                this.data.push(memblock);
+                memblock.assignLocation(section, this.dataOffset, this.currentDataOffset);
+
+                console.log(
+                    `Binding ${dataType.getDataItem().name} to DATA at ${memblock
+                        .getAbsoluteOffset()
+                        .toString(16)}`,
+                );
+                this.currentDataOffset = this.currentDataOffset.plus(memblock.getSize());
+                break;
+
+            default:
+                throw `Unrecognized calldata section: ${section}`;
+        }
+
+        this.bindList[dataType.getId()] = memblock;
+        dataType.rbind(memblock);
+    }
+
+    public getHexValue(): string {
+        let hexValue = `${this.selector}`;
+        _.each(this.params, (memblock: Memblock) => {
+            hexValue += memblock.get();
+        });
+        _.each(this.data, (memblock: Memblock) => {
+            hexValue += memblock.get();
+        });
+
+        return hexValue;
+    }
+}
+
+export abstract class DataType {
+    private dataItem: DataItem;
+    private hexValue: string;
+    protected memblock: Memblock | undefined;
+    protected children: DataType[];
+
+    constructor(dataItem: DataItem) {
+        this.dataItem = dataItem;
+        this.hexValue = '0x';
+        this.memblock = undefined;
+        this.children = [];
+    }
+
+    protected assignHexValue(hexValue: string) {
+        this.hexValue = hexValue;
+    }
+
+    public getHexValue(): string {
+        return this.hexValue;
+    }
+
+    public getDataItem(): DataItem {
+        return this.dataItem;
+    }
+
+    public rbind(memblock: Memblock) {
+        this.memblock = memblock;
+    }
+
+    public bind(calldata: Calldata, section: CalldataSection) {
+        calldata.bind(this, section);
+        _.each(this.getChildren(), (child: DataType) => {
+            child.bind(calldata, CalldataSection.DATA);
+        });
+    }
+
+    public getId(): string {
+        return this.dataItem.name;
+    }
+
+    public getOffset(): BigNumber {
+        if (this.memblock === undefined) return new BigNumber(0);
+        return this.memblock.getOffset();
+    }
+
+    public getAbsoluteOffset(): BigNumber {
+        if (this.memblock === undefined) return new BigNumber(0);
+        return this.memblock.getAbsoluteOffset();
+    }
+    /*
+        public getSize(): BigNumber {
+            if (this.memblock === undefined) return new BigNumber(0);
+            return this.memblock.getSize();
+        }
+        */
+
+    public getChildren(): DataType[] {
+        return this.children;
+    }
+
+    public getSize(): BigNumber {
+        return this.getHeaderSize().plus(this.getBodySize());
+    }
+
+    public abstract assignValue(value: any): void;
+    public abstract getSignature(): string;
+    public abstract isStatic(): boolean;
+    public abstract getHeaderSize(): BigNumber;
+    public abstract getBodySize(): BigNumber;
+}
+
+export abstract class StaticDataType extends DataType {
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+    }
+}
+
+export abstract class DynamicDataType extends DataType {
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+    }
+}
+
+export class Address extends StaticDataType {
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+        expect(Address.matchGrammar(dataItem.type)).to.be.true();
+    }
+
+    public assignValue(value: string) {
+        const evmWordWidth = 32;
+        const hexValue = ethUtil.bufferToHex(ethUtil.setLengthLeft(ethUtil.toBuffer(value), evmWordWidth));
+        this.assignHexValue(hexValue);
+    }
+
+    public getSignature(): string {
+        return `address`;
+    }
+
+    public isStatic(): boolean {
+        return true;
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        return new BigNumber(32);
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return type === 'address';
+    }
+}
+
+export class Bool extends StaticDataType {
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+        expect(Bool.matchGrammar(dataItem.type)).to.be.true();
+    }
+
+    public assignValue(value: boolean) {
+        const evmWordWidth = 32;
+        const encodedValue = value === true ? '0x1' : '0x0';
+        const hexValue = ethUtil.bufferToHex(ethUtil.setLengthLeft(ethUtil.toBuffer(encodedValue), evmWordWidth));
+        this.assignHexValue(hexValue);
+    }
+
+    public getSignature(): string {
+        return 'bool';
+    }
+
+    public isStatic(): boolean {
+        return true;
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        return new BigNumber(32);
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return type === 'bool';
+    }
+}
+
+abstract class Number extends StaticDataType {
+    static MAX_WIDTH: number = 256;
+    static DEFAULT_WIDTH: number = Number.MAX_WIDTH;
+    width: number = Number.DEFAULT_WIDTH;
+
+    constructor(dataItem: DataItem, matcher: RegExp) {
+        super(dataItem);
+        const matches = matcher.exec(dataItem.type);
+        expect(matches).to.be.not.null();
+        if (matches !== null && matches.length === 2 && matches[1] !== undefined) {
+            this.width = parseInt(matches[1]);
+        } else {
+            this.width = 256;
+        }
+    }
+
+    public assignValue(value: BigNumber) {
+        if (value.greaterThan(this.getMaxValue())) {
+            throw `tried to assign value of ${value}, which exceeds max value of ${this.getMaxValue()}`;
+        } else if (value.lessThan(this.getMinValue())) {
+            throw `tried to assign value of ${value}, which exceeds min value of ${this.getMinValue()}`;
+        }
+
+        const hexBase = 16;
+        const evmWordWidth = 32;
+        let valueBuf: Buffer;
+        if (value.greaterThanOrEqualTo(0)) {
+            valueBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(`0x${value.toString(hexBase)}`), evmWordWidth);
+        } else {
+            // BigNumber can't write a negative hex value, so we use twos-complement conversion to do it ourselves.
+            // Step 1/3: Convert value to positive binary string
+            const binBase = 2;
+            const valueBin = value.times(-1).toString(binBase);
+
+            // Step 2/3: Invert binary value
+            const bitsInEvmWord = 256;
+            let invertedValueBin = '1'.repeat(bitsInEvmWord - valueBin.length);
+            _.each(valueBin, (bit: string) => {
+                invertedValueBin += bit === '1' ? '0' : '1';
+            });
+            const invertedValue = new BigNumber(invertedValueBin, binBase);
+
+            // Step 3/3: Add 1 to inverted value
+            // The result is the two's-complement represent of the input value.
+            const negativeValue = invertedValue.plus(1);
+
+            // Convert the negated value to a hex string
+            valueBuf = ethUtil.setLengthLeft(
+                ethUtil.toBuffer(`0x${negativeValue.toString(hexBase)}`),
+                evmWordWidth,
+            );
+        }
+
+        const encodedValue = ethUtil.bufferToHex(valueBuf);
+        this.assignHexValue(encodedValue);
+    }
+
+    public isStatic(): boolean {
+        return true;
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        return new BigNumber(32);
+    }
+
+    public abstract getMaxValue(): BigNumber;
+    public abstract getMinValue(): BigNumber;
+}
+
+export class Int extends Number {
+    static matcher = RegExp(
+        '^int(8|16|24|32|40|48|56|64|72|88|96|104|112|120|128|136|144|152|160|168|176|184|192|200|208|216|224|232|240|248|256){0,1}$',
+    );
+
+    constructor(dataItem: DataItem) {
+        super(dataItem, Int.matcher);
+    }
+
+    public getMaxValue(): BigNumber {
+        return new BigNumber(2).toPower(this.width - 1).sub(1);
+    }
+
+    public getMinValue(): BigNumber {
+        return new BigNumber(2).toPower(this.width - 1).times(-1);
+    }
+
+    public getSignature(): string {
+        return `int${this.width}`;
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return this.matcher.test(type);
+    }
+}
+
+export class UInt extends Number {
+    static matcher = RegExp(
+        '^uint(8|16|24|32|40|48|56|64|72|88|96|104|112|120|128|136|144|152|160|168|176|184|192|200|208|216|224|232|240|248|256){0,1}$',
+    );
+
+    constructor(dataItem: DataItem) {
+        super(dataItem, UInt.matcher);
+    }
+
+    public getMaxValue(): BigNumber {
+        return new BigNumber(2).toPower(this.width).sub(1);
+    }
+
+    public getMinValue(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getSignature(): string {
+        return `uint${this.width}`;
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return this.matcher.test(type);
+    }
+}
+
+export class Byte extends StaticDataType {
+    static matcher = RegExp(
+        '^(byte|bytes(1|2|3|4|5|6|7|8|9|10|11|12|13|14|15|16|17|18|19|20|21|22|23|24|25|26|27|28|29|30|31|32))$',
+    );
+
+    static DEFAULT_WIDTH = 1;
+    width: number = Byte.DEFAULT_WIDTH;
+
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+        const matches = Byte.matcher.exec(dataItem.type);
+        expect(matches).to.be.not.null();
+        if (matches !== null && matches.length === 3 && matches[2] !== undefined) {
+            this.width = parseInt(matches[2]);
+        } else {
+            this.width = Byte.DEFAULT_WIDTH;
+        }
+    }
+
+    public assignValue(value: string | Buffer) {
+        // Convert value into a buffer and do bounds checking
+        const valueBuf = ethUtil.toBuffer(value);
+        if (valueBuf.byteLength > this.width) {
+            throw new Error(
+                `Tried to assign ${value} (${
+                valueBuf.byteLength
+                } bytes), which exceeds max bytes that can be stored in a ${this.getSignature()}`,
+            );
+        } else if (value.length % 2 !== 0) {
+            throw new Error(`Tried to assign ${value}, which is contains a half-byte. Use full bytes only.`);
+        }
+
+        // Store value as hex
+        const evmWordWidth = 32;
+        const paddedValue = ethUtil.setLengthRight(valueBuf, evmWordWidth);
+        const hexValue = ethUtil.bufferToHex(paddedValue);
+        this.assignHexValue(hexValue);
+    }
+
+    public getSignature(): string {
+        // Note that `byte` reduces to `bytes1`
+        return `bytes${this.width}`;
+    }
+
+    public isStatic(): boolean {
+        return true;
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        return new BigNumber(32);
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return this.matcher.test(type);
+    }
+}
+
+export class Bytes extends DynamicDataType {
+    static UNDEFINED_LENGTH = new BigNumber(-1);
+    length: BigNumber = Bytes.UNDEFINED_LENGTH;
+
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+        expect(Bytes.matchGrammar(dataItem.type)).to.be.true();
+    }
+
+    public assignValue(value: string | Buffer) {
+        if (typeof value === 'string' && !value.startsWith('0x')) {
+            throw new Error(`Input value must be hex (prefixed with 0x). Actual value is '${value}'`);
+        }
+        const valueBuf = ethUtil.toBuffer(value);
+        if (value.length % 2 !== 0) {
+            throw new Error(`Tried to assign ${value}, which is contains a half-byte. Use full bytes only.`);
+        }
+
+        const wordsForValue = Math.ceil(valueBuf.byteLength / 32);
+        const paddedBytesForValue = wordsForValue * 32;
+        const paddedValueBuf = ethUtil.setLengthRight(ethUtil.toBuffer(value), paddedBytesForValue);
+        const paddedLengthBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(valueBuf.byteLength), 32);
+        const encodedValueBuf = Buffer.concat([paddedLengthBuf, paddedValueBuf]);
+        const encodedValue = ethUtil.bufferToHex(encodedValueBuf);
+
+        this.assignHexValue(encodedValue);
+    }
+
+    public getSignature(): string {
+        return 'bytes';
+    }
+
+    public isStatic(): boolean {
+        return false;
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        return new BigNumber(this.getHexValue().length);
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return type === 'bytes';
+    }
+}
+
+export class SolString extends DynamicDataType {
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+        expect(SolString.matchGrammar(dataItem.type)).to.be.true();
+    }
+
+    public assignValue(value: string) {
+        const wordsForValue = Math.ceil(value.length / 32);
+        const paddedBytesForValue = wordsForValue * 32;
+        const valueBuf = ethUtil.setLengthRight(ethUtil.toBuffer(value), paddedBytesForValue);
+        const lengthBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(value.length), 32);
+        const encodedValueBuf = Buffer.concat([lengthBuf, valueBuf]);
+        const encodedValue = ethUtil.bufferToHex(encodedValueBuf);
+
+        this.assignHexValue(encodedValue);
+    }
+
+    public getSignature(): string {
+        return 'string';
+    }
+
+    public isStatic(): boolean {
+        return false;
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        return new BigNumber(this.getHexValue().length);
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return type === 'string';
+    }
+}
+
+export class SolArray extends DynamicDataType {
+    static matcher = RegExp('^(.+)\\[([0-9]*)\\]$');
+    static UNDEFINED_LENGTH = new BigNumber(-1);
+    length: BigNumber = SolArray.UNDEFINED_LENGTH;
+    type: string = '[undefined]';
+    isLengthDefined: boolean;
+    isStaticArray: boolean; // An array is dynamic if it's lenghth is undefined or if its children are dynamic.
+    private elements: DataType[];
+
+    /*
+    --- Layout 1: Fixed Length Array with Static Types ---
+    Elem1, Elem2, ..., ElemN
+
+    --- Layout 2: Fixed Length Array with Dynamic Types ---
+    PtrToArray, ..., Elem1, Elem2, ..., ElemN
+
+    --- Layout 3: Dynamic Length Array with Static Types ---
+    PtrToArray, ..., ArrayLength, Elem1, Elem2, ..., ElemN
+
+    --- Layout 4: Dynamic Length Array with Dynamic Types ---
+    PtrToArray, ..., ArrayLength, PtrToElem1, PtrToElem2, ..., PtrToElemN, ..., Elem1, Elem2, ..., ElemN
+    */
+
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+        const matches = SolArray.matcher.exec(dataItem.type);
+        expect(matches).to.be.not.null();
+        console.log(JSON.stringify(matches));
+        if (matches === null || matches.length !== 3) {
+            throw new Error(`Could not parse array: ${dataItem.type}`);
+        } else if (matches[1] === undefined) {
+            throw new Error(`Could not parse array type: ${dataItem.type}`);
+        } else if (matches[2] === undefined) {
+            throw new Error(`Could not parse array length: ${dataItem.type}`);
+        }
+
+        this.elements = [];
+
+        // Check if length is undefined
+        if (matches[2] === '') {
+            this.type = matches[1];
+            this.length = SolArray.UNDEFINED_LENGTH;
+            this.isLengthDefined = false;
+            this.isStaticArray = false;
+            return;
+        }
+
+        // Parse out array type/length and construct children
+        this.isLengthDefined = true;
+        this.type = matches[1];
+        this.length = new BigNumber(matches[2], 10);
+        if (this.length.lessThan(1)) {
+            throw new Error(`Bad array length: ${JSON.stringify(this.length)}`);
+        }
+        this.constructChildren();
+
+        // Check if we're static or not
+        this.isStaticArray = !(this.elements[0] instanceof Pointer);  //this.elements[0].isStatic();
+        //throw new Error(`Am I static? ${this.isStaticArray}`);
+    }
+
+    private constructChildren() {
+        for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
+            const childDataItem = {
+                type: this.type,
+                name: `${this.getDataItem().name}[${idx.toString(10)}]`,
+            } as DataItem;
+            const child = DataTypeFactory.create(childDataItem, this);
+            this.elements.push(child);
+            if (child instanceof Pointer) {
+                const pointsTo = child.getChildren()[0];
+                console.log(JSON.stringify(pointsTo));
+                this.children.push(pointsTo); // DataType pointing to
+            }
+        }
+    }
+
+    // @TODO: HACKY -- shouldn't really have children for a 
+    /*
+    public getChildren(): DataType[] {
+        if (this.isStatic()) {
+            return [];
+        } else {
+            return this.children;
+        }
+    }*/
+
+    public assignValue(value: any[]) {
+        // Sanity check length
+        const valueLength = new BigNumber(value.length);
+        if (this.length !== SolArray.UNDEFINED_LENGTH && valueLength.equals(this.length) === false) {
+            throw new Error(
+                `Expected array of length ${JSON.stringify(this.length)}, but got array of length ${JSON.stringify(
+                    valueLength,
+                )}`,
+            );
+        }
+
+        // Assign length if not already set
+        if (this.length === SolArray.UNDEFINED_LENGTH) {
+            this.length = valueLength;
+            this.constructChildren();
+        }
+
+        // Assign values to children
+        for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
+            const idxNumber = idx.toNumber();
+            this.elements[idxNumber].assignValue(value[idxNumber]);
+        }
+    }
+
+    public getHexValue(): string {
+        let valueBuf = new Buffer("");
+
+        if (this.isLengthDefined === false) {
+            // Must include the array length
+            const lengthBufUnpadded = ethUtil.toBuffer(`0x${this.length.toString(16)}`);
+            const lengthBuf = ethUtil.setLengthLeft(lengthBufUnpadded, 32);
+            valueBuf = lengthBuf;
+        }
+
+        for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
+            const idxNumber = idx.toNumber();
+            const childValueHex = this.elements[idxNumber].getHexValue();
+            const childValueBuf = ethUtil.toBuffer(childValueHex);
+            valueBuf = Buffer.concat([valueBuf, childValueBuf]);
+        }
+
+        // Convert value buffer to hex
+        const valueHex = ethUtil.bufferToHex(valueBuf);
+        return valueHex;
+    }
+
+    public isStatic(): boolean {
+        return this.isStaticArray;
+    }
+
+    public getHeaderSize(): BigNumber {
+        let size = new BigNumber(0);
+        if (!this.isLengthDefined) {
+            size = new BigNumber(32); // stores length of bytes
+        }
+        return size;
+    }
+
+    public getBodySize(): BigNumber {
+        const evmWordWidth = new BigNumber(32);
+        const body = this.length.times(evmWordWidth);
+        return body;
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return this.matcher.test(type);
+    }
+
+    public getSignature(): string {
+        let type = this.type;
+        if (this.type === 'tuple') {
+            let tupleDataItem = {
+                type: 'tuple',
+                name: 'N/A',
+            } as DataItem;
+            const tupleComponents = this.getDataItem().components;
+            if (tupleComponents !== undefined) {
+                tupleDataItem.components = tupleComponents;
+            }
+            const tuple = new Tuple(tupleDataItem);
+            type = tuple.getSignature();
+        }
+
+        if (this.length.equals(SolArray.UNDEFINED_LENGTH)) {
+            return `${type}[]`;
+        }
+        return `${type}[${this.length}]`;
+    }
+}
+
+export class Tuple extends DynamicDataType {
+    private length: BigNumber;
+    private childMap: { [key: string]: number };
+
+    constructor(dataItem: DataItem) {
+        super(dataItem);
+        expect(Tuple.matchGrammar(dataItem.type)).to.be.true();
+        this.length = new BigNumber(0);
+        this.childMap = {};
+        if (dataItem.components !== undefined) {
+            this.constructChildren(dataItem.components);
+            this.length = new BigNumber(dataItem.components.length);
+        } else {
+            throw new Error('Components undefined');
+        }
+    }
+
+    private constructChildren(dataItems: DataItem[]) {
+        _.each(dataItems, (dataItem: DataItem) => {
+            const childDataItem = {
+                type: dataItem.type,
+                name: `${this.getDataItem().name}.${dataItem.name}`,
+            } as DataItem;
+            const child = DataTypeFactory.create(childDataItem, this);
+            this.childMap[dataItem.name] = this.children.length;
+            this.children.push(child);
+        });
+    }
+
+    private assignValueFromArray(value: any[]) {
+        // Sanity check length
+        const valueLength = new BigNumber(value.length);
+        if (this.length !== SolArray.UNDEFINED_LENGTH && valueLength.equals(this.length) === false) {
+            throw new Error(
+                `Expected array of ${JSON.stringify(
+                    this.length,
+                )} elements, but got array of length ${JSON.stringify(valueLength)}`,
+            );
+        }
+
+        // Assign values to children
+        for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
+            const idxNumber = idx.toNumber();
+            this.children[idxNumber].assignValue(value[idxNumber]);
+        }
+    }
+
+    private assignValueFromObject(obj: object) {
+        let childMap = _.cloneDeep(this.childMap);
+        _.forOwn(obj, (value: any, key: string) => {
+            if (key in childMap === false) {
+                throw new Error(`Could not assign tuple to object: unrecognized key '${key}'`);
+            }
+            this.children[this.childMap[key]].assignValue(value);
+            delete childMap[key];
+        });
+
+        if (Object.keys(childMap).length !== 0) {
+            throw new Error(`Could not assign tuple to object: missing keys ${Object.keys(childMap)}`);
+        }
+    }
+
+    public assignValue(value: any[] | object) {
+        if (value instanceof Array) {
+            this.assignValueFromArray(value);
+        } else if (typeof value === 'object') {
+            this.assignValueFromObject(value);
+        } else {
+            throw new Error(`Unexpected type for ${value}`);
+        }
+    }
+
+    public getHexValue(): string {
+        return '0x';
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        const evmWordWidth = new BigNumber(32);
+        const size = this.length.times(evmWordWidth);
+        return size;
+    }
+
+    public getSignature(): string {
+        // Compute signature
+        let signature = `(`;
+        _.each(this.children, (child: DataType, i: number) => {
+            signature += child.getSignature();
+            if (i < this.children.length - 1) {
+                signature += ',';
+            }
+        });
+        signature += ')';
+        return signature;
+    }
+
+    public isStatic(): boolean {
+        return false; // @TODO: True in every case or only when dynamic data?
+    }
+
+    public static matchGrammar(type: string): boolean {
+        return type === 'tuple';
+    }
+}
+
+/* TODO
+class Fixed extends StaticDataType {}
+
+class UFixed extends StaticDataType {}*/
+
+export class Pointer extends StaticDataType {
+    destDataType: DynamicDataType;
+    parentDataType: DataType;
+
+    constructor(destDataType: DynamicDataType, parentDataType: DataType) {
+        const destDataItem = destDataType.getDataItem();
+        const dataItem = { name: `ptr<${destDataItem.name}>`, type: `ptr<${destDataItem.type}>` } as DataItem;
+        super(dataItem);
+        this.destDataType = destDataType;
+        this.parentDataType = parentDataType;
+        this.children.push(destDataType);
+    }
+
+    /*
+    public assignValue(destDataType: DynamicDataType) {
+        this.destDataType = destDataType;
+    }*/
+
+    public assignValue(value: any) {
+        this.destDataType.assignValue(value);
+    }
+
+    public getHexValue(): string {
+        console.log(
+            '*'.repeat(40),
+            this.destDataType.getAbsoluteOffset().toString(16),
+            '^'.repeat(150),
+            this.parentDataType.getAbsoluteOffset().toString(16),
+        );
+
+        let offset = this.destDataType
+            .getAbsoluteOffset()
+            .minus(this.parentDataType.getAbsoluteOffset())
+            .minus(this.parentDataType.getHeaderSize());
+
+        console.log("OFFSET == ", JSON.stringify(offset), " or in hex -- 0x", offset.toString(16));
+
+        const hexBase = 16;
+        const evmWordWidth = 32;
+        const valueBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(`0x${offset.toString(hexBase)}`), evmWordWidth);
+        const encodedValue = ethUtil.bufferToHex(valueBuf);
+        return encodedValue;
+    }
+
+    public getSignature(): string {
+        return this.destDataType.getSignature();
+    }
+
+    public isStatic(): boolean {
+        return true;
+    }
+
+    public getHeaderSize(): BigNumber {
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        return new BigNumber(32);
+    }
+
+}
+
+export class DataTypeFactory {
+    public static mapDataItemToDataType(dataItem: DataItem): DataType {
+        console.log(`Type: ${dataItem.type}`);
+
+        if (SolArray.matchGrammar(dataItem.type)) return new SolArray(dataItem);
+        if (Address.matchGrammar(dataItem.type)) return new Address(dataItem);
+        if (Bool.matchGrammar(dataItem.type)) return new Bool(dataItem);
+        if (Int.matchGrammar(dataItem.type)) return new Int(dataItem);
+        if (UInt.matchGrammar(dataItem.type)) return new UInt(dataItem);
+        if (Byte.matchGrammar(dataItem.type)) return new Byte(dataItem);
+        if (Tuple.matchGrammar(dataItem.type)) return new Tuple(dataItem);
+        if (SolArray.matchGrammar(dataItem.type)) return new SolArray(dataItem);
+        if (Bytes.matchGrammar(dataItem.type)) return new Bytes(dataItem);
+        if (SolString.matchGrammar(dataItem.type)) return new SolString(dataItem);
+        //if (Fixed.matchGrammar(dataItem.type)) return Fixed(dataItem);
+        //if (UFixed.matchGrammar(dataItem.type)) return UFixed(dataItem);
+
+        throw new Error(`Unrecognized data type: '${dataItem.type}'`);
+    }
+
+    public static create(dataItem: DataItem, parentDataType: DataType): DataType {
+        const dataType = DataTypeFactory.mapDataItemToDataType(dataItem);
+        if (dataType.isStatic()) {
+            return dataType;
+        } else {
+            const pointer = new Pointer(dataType, parentDataType);
+            return pointer;
+        }
+
+        throw new Error(`Unrecognized instance type: '${dataType}'`);
+    }
+}
+
+class Queue<T> {
+    private store: T[] = [];
+    push(val: T) {
+        this.store.push(val);
+    }
+    pop(): T | undefined {
+        return this.store.shift();
+    }
+}
+
+export class Method extends DataType {
+    name: string;
+    params: DataType[];
+    private signature: string;
+    selector: string;
+
+    constructor(abi: MethodAbi) {
+        super({ type: 'method', name: abi.name });
+        this.name = abi.name;
+        this.params = [];
+
+        _.each(abi.inputs, (input: DataItem) => {
+            this.params.push(DataTypeFactory.create(input, this));
+        });
+
+        // Compute signature
+        this.signature = `${this.name}(`;
+        _.each(this.params, (param: DataType, i: number) => {
+            this.signature += param.getSignature();
+            if (i < this.params.length - 1) {
+                this.signature += ',';
+            }
+        });
+        this.signature += ')';
+
+        // Compute selector
+        this.selector = ethUtil.bufferToHex(ethUtil.toBuffer(ethUtil.sha3(this.signature).slice(0, 4)));
+
+        console.log(`--SIGNATURE--\n${this.signature}\n---------\n`);
+        console.log(`--SELECTOR--\n${this.selector}\n---------\n`);
+    }
+
+    public getSignature(): string {
+        return this.signature;
+    }
+
+    public assignValue(args: any[]) {
+        _.each(this.params, (param: DataType, i: number) => {
+            // Assign value to parameter
+            try {
+                param.assignValue(args[i]);
+            } catch (e) {
+                console.log('Failed to assign to ', param.getDataItem().name);
+                throw e;
+            }
+
+            if (param instanceof Pointer) {
+                this.children.push(param.getChildren()[0]);
+            }
+        });
+    }
+
+    public getHexValue(): string {
+        let value = "";
+        _.each(this.params, (param: DataType) => {
+            value += param.getHexValue();
+        });
+
+        return value;
+    }
+
+    public encode(args: any[]): string {
+        this.assignValue(args);
+        const calldata = new Calldata(this.selector, this.params.length);
+        this.bind(calldata, CalldataSection.PARAMS);
+
+        return calldata.getHexValue();
+    }
+
+    public isStatic(): boolean {
+        return true;
+    }
+
+    public getHeaderSize(): BigNumber {
+        // Exclude selector
+        return new BigNumber(0);
+    }
+
+    public getBodySize(): BigNumber {
+        const nParams = new BigNumber(this.params.length);
+        const evmWordWidth = new BigNumber(32);
+        const size = nParams.times(evmWordWidth);
+        return size;
+    }
+
+    /*
+    encodeOptimized(args: any[]): string {
+        const calldata = new Memory();
+        // Assign values
+        optimizableParams : StaticDataType = [];
+        _.each(this.params, function(args: any[], i: number, param: DataType) {
+            param.assignValue(args[i]);
+            if (param instanceof DynamicDataType) {
+
+            }
+        });
+
+        // Find non-parameter leaves
+
+
+        return '';
+    } */
+
+    /*
+    decode(rawCalldata: string): any[] {
+        const calldata = new Calldata(this.name, this.params.length);
+        calldata.assignRaw(rawCalldata);
+        let args: any[];
+        let params = this.params;
+        _.each(params, function(args: any[], i: number, param: DataType) {
+            param.decodeFromCalldata(calldata);
+            args.push(param.getValue());
+        });
+
+        return args;
+    }*/
+}
\ No newline at end of file
diff --git a/packages/order-utils/test/abi_encoder_test.ts b/packages/order-utils/test/abi_encoder_test.ts
index b8f1d39ad..315537226 100644
--- a/packages/order-utils/test/abi_encoder_test.ts
+++ b/packages/order-utils/test/abi_encoder_test.ts
@@ -12,1294 +12,18 @@ import { MethodAbi, DataItem } from 'ethereum-types';
 
 import { BigNumber } from '@0x/utils';
 import { assert } from '@0x/order-utils/src/assert';
-
-const simpleAbi = {
-    constant: false,
-    inputs: [
-        {
-            name: 'greg',
-            type: 'uint256',
-        },
-        {
-            name: 'gregStr',
-            type: 'string',
-        },
-    ],
-    name: 'simpleFunction',
-    outputs: [],
-    payable: false,
-    stateMutability: 'nonpayable',
-    type: 'function',
-} as MethodAbi;
-
-const stringAbi = {
-    constant: false,
-    inputs: [
-        {
-            name: 'greg',
-            type: 'string[]',
-        },
-    ],
-    name: 'simpleFunction',
-    outputs: [],
-    payable: false,
-    stateMutability: 'nonpayable',
-    type: 'function',
-} as MethodAbi;
-
-const tupleAbi = {
-    constant: false,
-    inputs: [
-        {
-            components: [
-                {
-                    name: 'someUint',
-                    type: 'uint256',
-                },
-                {
-                    name: 'someStr',
-                    type: 'string',
-                },
-            ],
-            name: 'order',
-            type: 'tuple',
-        },
-    ],
-    name: 'simpleFunction',
-    outputs: [],
-    payable: false,
-    stateMutability: 'nonpayable',
-    type: 'function',
-} as MethodAbi;
-
-const staticArrayAbi = {
-    constant: false,
-    inputs: [
-        {
-            name: 'someStaticArray',
-            type: 'uint8[3]',
-        }
-    ],
-    name: 'simpleFunction',
-    outputs: [],
-    payable: false,
-    stateMutability: 'nonpayable',
-    type: 'function',
-} as MethodAbi;
-
-const crazyAbi = {
-    constant: false,
-    inputs: [
-        /*{
-            name: 'someUInt256',
-            type: 'uint256',
-        },
-        {
-            name: 'someInt256',
-            type: 'int256',
-        },
-        {
-            name: 'someInt32',
-            type: 'int32',
-        },
-        {
-            name: 'someByte',
-            type: 'byte',
-        },
-        {
-            name: 'someBytes32',
-            type: 'bytes32',
-        },
-        {
-            name: 'someBytes',
-            type: 'bytes',
-        },
-        {
-            name: 'someString',
-            type: 'string',
-        },*/
-        /*{
-            name: 'someAddress',
-            type: 'address',
-        },
-        {
-            name: 'someBool',
-            type: 'bool',
-        },*/
-
-        {
-            name: 'someStaticArray',
-            type: 'uint8[3]',
-        },
-        {
-            name: 'someStaticArrayWithDynamicMembers',
-            type: 'string[2]',
-        },
-        {
-            name: 'someDynamicArrayWithDynamicMembers',
-            type: 'bytes[]',
-        },
-        {
-            name: 'some2DArray',
-            type: 'string[][]',
-        },
-        {
-            name: 'someTuple',
-            type: 'tuple',
-            components: [
-                {
-                    name: 'someUint32',
-                    type: 'uint32',
-                },
-                {
-                    name: 'someStr',
-                    type: 'string',
-                },
-            ],
-        },
-        {
-            name: 'someTupleWithDynamicTypes',
-            type: 'tuple',
-            components: [
-                {
-                    name: 'someUint',
-                    type: 'uint256',
-                },
-                {
-                    name: 'someStr',
-                    type: 'string',
-                },
-                //{
-                //      name: 'someStrArray',
-                //     type: 'string[]',
-                /// },
-                {
-                    name: 'someBytes',
-                    type: 'bytes',
-                },
-                {
-                    name: 'someAddress',
-                    type: 'address',
-                },
-            ],
-        } /*,
-        {
-            name: 'someArrayOfTuplesWithDynamicTypes',
-            type: 'tuple[]',
-            components: [
-                {
-                    name: 'someUint',
-                    type: 'uint256',
-                },
-                {
-                    name: 'someStr',
-                    type: 'string',
-                },
-                {
-                    name: 'someStrArray',
-                    type: 'string[]',
-                },
-                {
-                    name: 'someBytes',
-                    type: 'bytes',
-                },
-                {
-                    name: 'someAddress',
-                    type: 'address',
-                },
-            ],
-        },*/,
-    ],
-    name: 'simpleFunction',
-    outputs: [],
-    payable: false,
-    stateMutability: 'nonpayable',
-    type: 'function',
-} as MethodAbi;
-
-const simpleAbi2 = {
-    constant: false,
-    inputs: [
-        {
-            name: 'someByte',
-            type: 'byte',
-        },
-        {
-            name: 'someBytes32',
-            type: 'bytes32',
-        },
-        {
-            name: 'someBytes',
-            type: 'bytes',
-        },
-        {
-            name: 'someString',
-            type: 'string',
-        },
-    ],
-    name: 'simpleFunction',
-    outputs: [],
-    payable: false,
-    stateMutability: 'nonpayable',
-    type: 'function',
-} as MethodAbi;
-
-const fillOrderAbi = {
-    constant: false,
-    inputs: [
-        {
-            components: [
-                {
-                    name: 'makerAddress',
-                    type: 'address',
-                },
-                {
-                    name: 'takerAddress',
-                    type: 'address',
-                },
-                {
-                    name: 'feeRecipientAddress',
-                    type: 'address',
-                },
-                {
-                    name: 'senderAddress',
-                    type: 'address',
-                },
-                {
-                    name: 'makerAssetAmount',
-                    type: 'uint256',
-                },
-                {
-                    name: 'takerAssetAmount',
-                    type: 'uint256',
-                },
-                {
-                    name: 'makerFee',
-                    type: 'uint256',
-                },
-                {
-                    name: 'takerFee',
-                    type: 'uint256',
-                },
-                {
-                    name: 'expirationTimeSeconds',
-                    type: 'uint256',
-                },
-                {
-                    name: 'salt',
-                    type: 'uint256',
-                },
-                {
-                    name: 'makerAssetData',
-                    type: 'bytes',
-                },
-                {
-                    name: 'takerAssetData',
-                    type: 'bytes',
-                },
-            ],
-            name: 'order',
-            type: 'tuple',
-        },
-        {
-            name: 'takerAssetFillAmount',
-            type: 'uint256',
-        },
-        {
-            name: 'salt',
-            type: 'uint256',
-        },
-        {
-            name: 'orderSignature',
-            type: 'bytes',
-        },
-        {
-            name: 'takerSignature',
-            type: 'bytes',
-        },
-    ],
-    name: 'fillOrder',
-    outputs: [],
-    payable: false,
-    stateMutability: 'nonpayable',
-    type: 'function',
-} as MethodAbi;
+import * as AbiEncoder from './abi_encoder';
+import * as AbiSamples from './abi_samples';
 
 chaiSetup.configure();
 const expect = chai.expect;
 
-namespace AbiEncoder {
-    class Word {
-        private value: string;
-
-        constructor(value?: string) {
-            if (value === undefined) {
-                this.value = '';
-            } else {
-                this.value = value;
-            }
-        }
-
-        public set(value: string) {
-            if (value.length !== 64) {
-                throw `Tried to create word that is not 32 bytes: ${value}`;
-            }
-
-            this.value = value;
-        }
-
-        public get(): string {
-            return this.value;
-        }
-
-        public getAsHex(): string {
-            return `0x${this.value}`;
-        }
-    }
-
-    export enum CalldataSection {
-        NONE,
-        PARAMS,
-        DATA,
-    }
-
-    class Memblock {
-        private dataType: DataType;
-        private location: { calldataSection: CalldataSection; sectionOffset: BigNumber; offset: BigNumber };
-
-        constructor(dataType: DataType) {
-            this.dataType = dataType;
-            this.location = {
-                calldataSection: CalldataSection.NONE,
-                sectionOffset: new BigNumber(0),
-                offset: new BigNumber(0),
-            };
-        }
-
-        public getSize(): BigNumber {
-            return new BigNumber(ethUtil.toBuffer(this.dataType.getHexValue()).byteLength);
-        }
-
-        public assignLocation(calldataSection: CalldataSection, sectionOffset: BigNumber, offset: BigNumber) {
-            this.location.calldataSection = calldataSection;
-            this.location.sectionOffset = sectionOffset;
-            this.location.offset = offset;
-        }
-
-        public get(): string {
-            return ethUtil.stripHexPrefix(this.dataType.getHexValue());
-        }
-
-        public getOffset(): BigNumber {
-            return this.location.offset;
-        }
-
-        public getAbsoluteOffset(): BigNumber {
-            return this.location.sectionOffset.plus(this.location.offset);
-        }
-
-        public getSection(): CalldataSection {
-            return this.location.calldataSection;
-        }
-    }
-
-    interface BindList {
-        [key: string]: Memblock;
-    }
-
-    export class Calldata {
-        private selector: string;
-        private params: Memblock[];
-        private data: Memblock[];
-        private dataOffset: BigNumber;
-        private currentDataOffset: BigNumber;
-        private currentParamOffset: BigNumber;
-        private bindList: BindList;
-
-        constructor(selector: string, nParams: number) {
-            this.selector = selector;
-            console.log(this.selector);
-            this.params = [];
-            this.data = [];
-            const evmWordSize = 32;
-            this.dataOffset = new BigNumber(nParams).times(evmWordSize);
-            this.currentDataOffset = new BigNumber(0);
-            this.currentParamOffset = new BigNumber(0);
-            this.bindList = {};
-        }
-
-        public bind(dataType: DataType, section: CalldataSection) {
-            if (dataType.getId() in this.bindList) {
-                throw `Rebind on ${dataType.getId()}`;
-            }
-            const memblock = new Memblock(dataType);
-            switch (section) {
-                case CalldataSection.PARAMS:
-                    this.params.push(memblock);
-                    memblock.assignLocation(section, new BigNumber(0), this.currentParamOffset);
-
-                    console.log(`Binding ${dataType.getDataItem().name} to PARAMS at ${this.currentParamOffset}`);
-                    this.currentParamOffset = this.currentParamOffset.plus(memblock.getSize());
-                    break;
-
-                case CalldataSection.DATA:
-                    this.data.push(memblock);
-                    memblock.assignLocation(section, this.dataOffset, this.currentDataOffset);
-
-                    console.log(
-                        `Binding ${dataType.getDataItem().name} to DATA at ${memblock
-                            .getAbsoluteOffset()
-                            .toString(16)}`,
-                    );
-                    this.currentDataOffset = this.currentDataOffset.plus(memblock.getSize());
-                    break;
-
-                default:
-                    throw `Unrecognized calldata section: ${section}`;
-            }
-
-            this.bindList[dataType.getId()] = memblock;
-            dataType.rbind(memblock);
-        }
-
-        public getHexValue(): string {
-            let hexValue = `${this.selector}`;
-            _.each(this.params, (memblock: Memblock) => {
-                hexValue += memblock.get();
-            });
-            _.each(this.data, (memblock: Memblock) => {
-                hexValue += memblock.get();
-            });
-
-            return hexValue;
-        }
-    }
-
-    export abstract class DataType {
-        private dataItem: DataItem;
-        private hexValue: string;
-        protected memblock: Memblock | undefined;
-        protected children: DataType[];
-
-        constructor(dataItem: DataItem) {
-            this.dataItem = dataItem;
-            this.hexValue = '0x';
-            this.memblock = undefined;
-            this.children = [];
-        }
-
-        protected assignHexValue(hexValue: string) {
-            this.hexValue = hexValue;
-        }
-
-        public getHexValue(): string {
-            return this.hexValue;
-        }
-
-        public getDataItem(): DataItem {
-            return this.dataItem;
-        }
-
-        public rbind(memblock: Memblock) {
-            this.memblock = memblock;
-        }
-
-        public bind(calldata: Calldata, section: CalldataSection) {
-            calldata.bind(this, section);
-        }
-
-        public getId(): string {
-            return this.dataItem.name;
-        }
-
-        public getOffset(): BigNumber {
-            if (this.memblock === undefined) return new BigNumber(0);
-            return this.memblock.getOffset();
-        }
-
-        public getAbsoluteOffset(): BigNumber {
-            if (this.memblock === undefined) return new BigNumber(0);
-            return this.memblock.getAbsoluteOffset();
-        }
-
-        public getSize(): BigNumber {
-            if (this.memblock === undefined) return new BigNumber(0);
-            return this.memblock.getSize();
-        }
-
-        public getChildren(): DataType[] {
-            return this.children;
-        }
-
-        public abstract assignValue(value: any): void;
-        public abstract getSignature(): string;
-        public abstract isStatic(): boolean;
-    }
-
-    export abstract class StaticDataType extends DataType {
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-        }
-    }
-
-    export abstract class DynamicDataType extends DataType {
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-        }
-    }
-
-    export class Address extends StaticDataType {
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-            expect(Address.matchGrammar(dataItem.type)).to.be.true();
-        }
-
-        public assignValue(value: string) {
-            const evmWordWidth = 32;
-            const hexValue = ethUtil.bufferToHex(ethUtil.setLengthLeft(ethUtil.toBuffer(value), evmWordWidth));
-            this.assignHexValue(hexValue);
-        }
-
-        public getSignature(): string {
-            return `address`;
-        }
-
-        public isStatic(): boolean {
-            return true;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return type === 'address';
-        }
-    }
-
-    export class Bool extends StaticDataType {
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-            expect(Bool.matchGrammar(dataItem.type)).to.be.true();
-        }
-
-        public assignValue(value: boolean) {
-            const evmWordWidth = 32;
-            const encodedValue = value === true ? '0x1' : '0x0';
-            const hexValue = ethUtil.bufferToHex(ethUtil.setLengthLeft(ethUtil.toBuffer(encodedValue), evmWordWidth));
-            this.assignHexValue(hexValue);
-        }
-
-        public getSignature(): string {
-            return 'bool';
-        }
-
-        public isStatic(): boolean {
-            return true;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return type === 'bool';
-        }
-    }
-
-    abstract class Number extends StaticDataType {
-        static MAX_WIDTH: number = 256;
-        static DEFAULT_WIDTH: number = Number.MAX_WIDTH;
-        width: number = Number.DEFAULT_WIDTH;
-
-        constructor(dataItem: DataItem, matcher: RegExp) {
-            super(dataItem);
-            const matches = matcher.exec(dataItem.type);
-            expect(matches).to.be.not.null();
-            if (matches !== null && matches.length === 2 && matches[1] !== undefined) {
-                this.width = parseInt(matches[1]);
-            } else {
-                this.width = 256;
-            }
-        }
-
-        public assignValue(value: BigNumber) {
-            if (value.greaterThan(this.getMaxValue())) {
-                throw `tried to assign value of ${value}, which exceeds max value of ${this.getMaxValue()}`;
-            } else if (value.lessThan(this.getMinValue())) {
-                throw `tried to assign value of ${value}, which exceeds min value of ${this.getMinValue()}`;
-            }
-
-            const hexBase = 16;
-            const evmWordWidth = 32;
-            let valueBuf: Buffer;
-            if (value.greaterThanOrEqualTo(0)) {
-                valueBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(`0x${value.toString(hexBase)}`), evmWordWidth);
-            } else {
-                // BigNumber can't write a negative hex value, so we use twos-complement conversion to do it ourselves.
-                // Step 1/3: Convert value to positive binary string
-                const binBase = 2;
-                const valueBin = value.times(-1).toString(binBase);
-
-                // Step 2/3: Invert binary value
-                const bitsInEvmWord = 256;
-                let invertedValueBin = '1'.repeat(bitsInEvmWord - valueBin.length);
-                _.each(valueBin, (bit: string) => {
-                    invertedValueBin += bit === '1' ? '0' : '1';
-                });
-                const invertedValue = new BigNumber(invertedValueBin, binBase);
-
-                // Step 3/3: Add 1 to inverted value
-                // The result is the two's-complement represent of the input value.
-                const negativeValue = invertedValue.plus(1);
-
-                // Convert the negated value to a hex string
-                valueBuf = ethUtil.setLengthLeft(
-                    ethUtil.toBuffer(`0x${negativeValue.toString(hexBase)}`),
-                    evmWordWidth,
-                );
-            }
-
-            const encodedValue = ethUtil.bufferToHex(valueBuf);
-            this.assignHexValue(encodedValue);
-        }
-
-        public isStatic(): boolean {
-            return true;
-        }
-
-        public abstract getMaxValue(): BigNumber;
-        public abstract getMinValue(): BigNumber;
-    }
-
-    export class Int extends Number {
-        static matcher = RegExp(
-            '^int(8|16|24|32|40|48|56|64|72|88|96|104|112|120|128|136|144|152|160|168|176|184|192|200|208|216|224|232|240|248|256){0,1}$',
-        );
-
-        constructor(dataItem: DataItem) {
-            super(dataItem, Int.matcher);
-        }
-
-        public getMaxValue(): BigNumber {
-            return new BigNumber(2).toPower(this.width - 1).sub(1);
-        }
-
-        public getMinValue(): BigNumber {
-            return new BigNumber(2).toPower(this.width - 1).times(-1);
-        }
-
-        public getSignature(): string {
-            return `int${this.width}`;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return this.matcher.test(type);
-        }
-    }
-
-    export class UInt extends Number {
-        static matcher = RegExp(
-            '^uint(8|16|24|32|40|48|56|64|72|88|96|104|112|120|128|136|144|152|160|168|176|184|192|200|208|216|224|232|240|248|256){0,1}$',
-        );
-
-        constructor(dataItem: DataItem) {
-            super(dataItem, UInt.matcher);
-        }
-
-        public getMaxValue(): BigNumber {
-            return new BigNumber(2).toPower(this.width).sub(1);
-        }
-
-        public getMinValue(): BigNumber {
-            return new BigNumber(0);
-        }
-
-        public getSignature(): string {
-            return `uint${this.width}`;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return this.matcher.test(type);
-        }
-    }
-
-    export class Byte extends StaticDataType {
-        static matcher = RegExp(
-            '^(byte|bytes(1|2|3|4|5|6|7|8|9|10|11|12|13|14|15|16|17|18|19|20|21|22|23|24|25|26|27|28|29|30|31|32))$',
-        );
-
-        static DEFAULT_WIDTH = 1;
-        width: number = Byte.DEFAULT_WIDTH;
-
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-            const matches = Byte.matcher.exec(dataItem.type);
-            expect(matches).to.be.not.null();
-            if (matches !== null && matches.length === 3 && matches[2] !== undefined) {
-                this.width = parseInt(matches[2]);
-            } else {
-                this.width = Byte.DEFAULT_WIDTH;
-            }
-        }
-
-        public assignValue(value: string | Buffer) {
-            // Convert value into a buffer and do bounds checking
-            const valueBuf = ethUtil.toBuffer(value);
-            if (valueBuf.byteLength > this.width) {
-                throw new Error(
-                    `Tried to assign ${value} (${
-                    valueBuf.byteLength
-                    } bytes), which exceeds max bytes that can be stored in a ${this.getSignature()}`,
-                );
-            } else if (value.length % 2 !== 0) {
-                throw new Error(`Tried to assign ${value}, which is contains a half-byte. Use full bytes only.`);
-            }
-
-            // Store value as hex
-            const evmWordWidth = 32;
-            const paddedValue = ethUtil.setLengthRight(valueBuf, evmWordWidth);
-            const hexValue = ethUtil.bufferToHex(paddedValue);
-            this.assignHexValue(hexValue);
-        }
-
-        public getSignature(): string {
-            // Note that `byte` reduces to `bytes1`
-            return `bytes${this.width}`;
-        }
-
-        public isStatic(): boolean {
-            return true;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return this.matcher.test(type);
-        }
-    }
-
-    export class Bytes extends DynamicDataType {
-        static UNDEFINED_LENGTH = new BigNumber(-1);
-        length: BigNumber = Bytes.UNDEFINED_LENGTH;
-
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-            expect(Bytes.matchGrammar(dataItem.type)).to.be.true();
-        }
-
-        public assignValue(value: string | Buffer) {
-            if (typeof value === 'string' && !value.startsWith('0x')) {
-                throw new Error(`Input value must be hex (prefixed with 0x). Actual value is '${value}'`);
-            }
-            const valueBuf = ethUtil.toBuffer(value);
-            if (value.length % 2 !== 0) {
-                throw new Error(`Tried to assign ${value}, which is contains a half-byte. Use full bytes only.`);
-            }
-
-            const wordsForValue = Math.ceil(valueBuf.byteLength / 32);
-            const paddedBytesForValue = wordsForValue * 32;
-            const paddedValueBuf = ethUtil.setLengthRight(ethUtil.toBuffer(value), paddedBytesForValue);
-            const paddedLengthBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(valueBuf.byteLength), 32);
-            const encodedValueBuf = Buffer.concat([paddedLengthBuf, paddedValueBuf]);
-            const encodedValue = ethUtil.bufferToHex(encodedValueBuf);
-
-            this.assignHexValue(encodedValue);
-        }
-
-        public getSignature(): string {
-            return 'bytes';
-        }
-
-        public isStatic(): boolean {
-            return false;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return type === 'bytes';
-        }
-    }
-
-    export class SolString extends DynamicDataType {
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-            expect(SolString.matchGrammar(dataItem.type)).to.be.true();
-        }
-
-        public assignValue(value: string) {
-            const wordsForValue = Math.ceil(value.length / 32);
-            const paddedBytesForValue = wordsForValue * 32;
-            const valueBuf = ethUtil.setLengthRight(ethUtil.toBuffer(value), paddedBytesForValue);
-            const lengthBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(value.length), 32);
-            const encodedValueBuf = Buffer.concat([lengthBuf, valueBuf]);
-            const encodedValue = ethUtil.bufferToHex(encodedValueBuf);
-
-            this.assignHexValue(encodedValue);
-        }
-
-        public getSignature(): string {
-            return 'string';
-        }
-
-        public isStatic(): boolean {
-            return false;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return type === 'string';
-        }
-    }
-
-    export class SolArray extends DynamicDataType {
-        static matcher = RegExp('^(.+)\\[([0-9]*)\\]$');
-        static UNDEFINED_LENGTH = new BigNumber(-1);
-        length: BigNumber = SolArray.UNDEFINED_LENGTH;
-        type: string = '[undefined]';
-        isLengthDefined: boolean;
-
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-            const matches = SolArray.matcher.exec(dataItem.type);
-            expect(matches).to.be.not.null();
-            console.log(JSON.stringify(matches));
-            if (matches === null || matches.length !== 3) {
-                throw new Error(`Could not parse array: ${dataItem.type}`);
-            } else if (matches[1] === undefined) {
-                throw new Error(`Could not parse array type: ${dataItem.type}`);
-            } else if (matches[2] === undefined) {
-                throw new Error(`Could not parse array length: ${dataItem.type}`);
-            }
-
-            // Check if length is undefined
-            if (matches[2] === '') {
-                this.type = matches[1];
-                this.length = SolArray.UNDEFINED_LENGTH;
-                this.isLengthDefined = false;
-                return;
-            }
-
-            // Parse out array type/length and construct children
-            this.isLengthDefined = true;
-            this.type = matches[1];
-            this.length = new BigNumber(matches[2], 10);
-            if (this.length.lessThan(0)) {
-                throw new Error(`Bad array length: ${JSON.stringify(this.length)}`);
-            }
-            this.constructChildren();
-        }
-
-        private constructChildren() {
-            for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
-                const childDataItem = {
-                    type: this.type,
-                    name: `${this.getDataItem().name}[${idx.toString(10)}]`,
-                } as DataItem;
-                const child = DataTypeFactory.create(childDataItem, this);
-                this.children.push(child);
-            }
-        }
-
-        // @TODO: HACKY -- shouldn't really have children for a 
-        public getChildren(): DataType[] {
-            if (this.isStatic()) {
-                return [];
-            } else {
-                return this.children;
-            }
-        }
-
-        public assignValue(value: any[]) {
-            // Sanity check length
-            const valueLength = new BigNumber(value.length);
-            if (this.length !== SolArray.UNDEFINED_LENGTH && valueLength.equals(this.length) === false) {
-                throw new Error(
-                    `Expected array of length ${JSON.stringify(this.length)}, but got array of length ${JSON.stringify(
-                        valueLength,
-                    )}`,
-                );
-            }
-
-            // Assign length if not already set
-            if (this.length === SolArray.UNDEFINED_LENGTH) {
-                this.length = valueLength;
-                this.constructChildren();
-            }
-
-            // Assign values to children
-            for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
-                const idxNumber = idx.toNumber();
-                this.children[idxNumber].assignValue(value[idxNumber]);
-            }
-        }
-
-        private getHexValueDynamicArray(): string {
-            const lengthBufUnpadded = ethUtil.toBuffer(`0x${this.length.toString(16)}`);
-            const lengthBuf = ethUtil.setLengthLeft(lengthBufUnpadded, 32);
-            let valueBuf = lengthBuf;
-
-            const valueHex = ethUtil.bufferToHex(valueBuf);
-            return valueHex;
-        }
-
-        private getHexValueStaticArray(): string {
-            let valueBuf = new Buffer("");
-
-            for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
-                const idxNumber = idx.toNumber();
-                const childValueHex = this.children[idxNumber].getHexValue();
-                const childValueBuf = ethUtil.toBuffer(childValueHex);
-                valueBuf = Buffer.concat([valueBuf, childValueBuf]);
-
-                console.log(JSON.stringify(idx));
-            }
-
-            // Convert value buffer to hex
-            const valueHex = ethUtil.bufferToHex(valueBuf);
-            return valueHex;
-        }
-
-        public getHexValue(): string {
-            if (this.isLengthDefined) {
-                return this.getHexValueStaticArray();
-            } else {
-                return this.getHexValueDynamicArray();
-            }
-        }
-
-        public isStatic(): boolean {
-            return this.isLengthDefined;
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return this.matcher.test(type);
-        }
-
-        public getSignature(): string {
-            let type = this.type;
-            if (this.type === 'tuple') {
-                let tupleDataItem = {
-                    type: 'tuple',
-                    name: 'N/A',
-                } as DataItem;
-                const tupleComponents = this.getDataItem().components;
-                if (tupleComponents !== undefined) {
-                    tupleDataItem.components = tupleComponents;
-                }
-                const tuple = new Tuple(tupleDataItem);
-                type = tuple.getSignature();
-            }
-
-            if (this.length.equals(SolArray.UNDEFINED_LENGTH)) {
-                return `${type}[]`;
-            }
-            return `${type}[${this.length}]`;
-        }
-    }
-
-    export class Tuple extends DynamicDataType {
-        private length: BigNumber;
-        private childMap: { [key: string]: number };
-
-        constructor(dataItem: DataItem) {
-            super(dataItem);
-            expect(Tuple.matchGrammar(dataItem.type)).to.be.true();
-            this.length = new BigNumber(0);
-            this.childMap = {};
-            if (dataItem.components !== undefined) {
-                this.constructChildren(dataItem.components);
-                this.length = new BigNumber(dataItem.components.length);
-            } else {
-                throw new Error('Components undefined');
-            }
-        }
-
-        private constructChildren(dataItems: DataItem[]) {
-            _.each(dataItems, (dataItem: DataItem) => {
-                const childDataItem = {
-                    type: dataItem.type,
-                    name: `${this.getDataItem().name}.${dataItem.name}`,
-                } as DataItem;
-                const child = DataTypeFactory.create(childDataItem, this);
-                this.childMap[dataItem.name] = this.children.length;
-                this.children.push(child);
-            });
-        }
-
-        private assignValueFromArray(value: any[]) {
-            // Sanity check length
-            const valueLength = new BigNumber(value.length);
-            if (this.length !== SolArray.UNDEFINED_LENGTH && valueLength.equals(this.length) === false) {
-                throw new Error(
-                    `Expected array of ${JSON.stringify(
-                        this.length,
-                    )} elements, but got array of length ${JSON.stringify(valueLength)}`,
-                );
-            }
-
-            // Assign values to children
-            for (let idx = new BigNumber(0); idx.lessThan(this.length); idx = idx.plus(1)) {
-                const idxNumber = idx.toNumber();
-                this.children[idxNumber].assignValue(value[idxNumber]);
-            }
-        }
-
-        private assignValueFromObject(obj: object) {
-            let childMap = _.cloneDeep(this.childMap);
-            _.forOwn(obj, (value: any, key: string) => {
-                if (key in childMap === false) {
-                    throw new Error(`Could not assign tuple to object: unrecognized key '${key}'`);
-                }
-                this.children[this.childMap[key]].assignValue(value);
-                delete childMap[key];
-            });
-
-            if (Object.keys(childMap).length !== 0) {
-                throw new Error(`Could not assign tuple to object: missing keys ${Object.keys(childMap)}`);
-            }
-        }
-
-        public assignValue(value: any[] | object) {
-            if (value instanceof Array) {
-                this.assignValueFromArray(value);
-            } else if (typeof value === 'object') {
-                this.assignValueFromObject(value);
-            } else {
-                throw new Error(`Unexpected type for ${value}`);
-            }
-        }
-
-        public getHexValue(): string {
-            return '0x';
-        }
-
-        public getSignature(): string {
-            // Compute signature
-            let signature = `(`;
-            _.each(this.children, (child: DataType, i: number) => {
-                signature += child.getSignature();
-                if (i < this.children.length - 1) {
-                    signature += ',';
-                }
-            });
-            signature += ')';
-            return signature;
-        }
-
-        public isStatic(): boolean {
-            return false; // @TODO: True in every case or only when dynamic data?
-        }
-
-        public static matchGrammar(type: string): boolean {
-            return type === 'tuple';
-        }
-    }
-
-    /* TODO
-    class Fixed extends StaticDataType {}
-
-    class UFixed extends StaticDataType {}*/
-
-    export class Pointer extends StaticDataType {
-        destDataType: DynamicDataType;
-        parentDataType: DataType;
-
-        constructor(destDataType: DynamicDataType, parentDataType: DataType) {
-            const destDataItem = destDataType.getDataItem();
-            const dataItem = { name: `ptr<${destDataItem.name}>`, type: `ptr<${destDataItem.type}>` } as DataItem;
-            super(dataItem);
-            this.destDataType = destDataType;
-            this.parentDataType = parentDataType;
-            this.children.push(destDataType);
-        }
-
-        /*
-        public assignValue(destDataType: DynamicDataType) {
-            this.destDataType = destDataType;
-        }*/
-
-        public assignValue(value: any) {
-            this.destDataType.assignValue(value);
-        }
-
-        public getHexValue(): string {
-            console.log(
-                '*'.repeat(40),
-                this.destDataType.getAbsoluteOffset().toString(16),
-                '^'.repeat(150),
-                this.parentDataType.getAbsoluteOffset().toString(16),
-            );
-
-            let offset = this.destDataType
-                .getAbsoluteOffset()
-                .minus(this.parentDataType.getAbsoluteOffset().plus(this.parentDataType.getSize()));
-            const hexBase = 16;
-            const evmWordWidth = 32;
-            const valueBuf = ethUtil.setLengthLeft(ethUtil.toBuffer(`0x${offset.toString(hexBase)}`), evmWordWidth);
-            const encodedValue = ethUtil.bufferToHex(valueBuf);
-            return encodedValue;
-        }
-
-        public getSignature(): string {
-            return this.destDataType.getSignature();
-        }
-
-        public isStatic(): boolean {
-            return true;
-        }
-
-        public encodeToCalldata(calldata: Calldata): void {
-            throw 2;
-        }
-    }
-
-    export class DataTypeFactory {
-        public static mapDataItemToDataType(dataItem: DataItem): DataType {
-            console.log(`Type: ${dataItem.type}`);
-
-            if (SolArray.matchGrammar(dataItem.type)) return new SolArray(dataItem);
-            if (Address.matchGrammar(dataItem.type)) return new Address(dataItem);
-            if (Bool.matchGrammar(dataItem.type)) return new Bool(dataItem);
-            if (Int.matchGrammar(dataItem.type)) return new Int(dataItem);
-            if (UInt.matchGrammar(dataItem.type)) return new UInt(dataItem);
-            if (Byte.matchGrammar(dataItem.type)) return new Byte(dataItem);
-            if (Tuple.matchGrammar(dataItem.type)) return new Tuple(dataItem);
-            if (SolArray.matchGrammar(dataItem.type)) return new SolArray(dataItem);
-            if (Bytes.matchGrammar(dataItem.type)) return new Bytes(dataItem);
-            if (SolString.matchGrammar(dataItem.type)) return new SolString(dataItem);
-            //if (Fixed.matchGrammar(dataItem.type)) return Fixed(dataItem);
-            //if (UFixed.matchGrammar(dataItem.type)) return UFixed(dataItem);
-
-            throw new Error(`Unrecognized data type: '${dataItem.type}'`);
-        }
-
-        public static create(dataItem: DataItem, parentDataType: DataType): DataType {
-            const dataType = DataTypeFactory.mapDataItemToDataType(dataItem);
-            if (dataType.isStatic()) {
-                return dataType;
-            } else {
-                const pointer = new Pointer(dataType, parentDataType);
-                return pointer;
-            }
-
-            throw new Error(`Unrecognized instance type: '${dataType}'`);
-        }
-    }
-
-    class Queue<T> {
-        private store: T[] = [];
-        push(val: T) {
-            this.store.push(val);
-        }
-        pop(): T | undefined {
-            return this.store.shift();
-        }
-    }
-
-    export class Method extends DataType {
-        name: string;
-        params: DataType[];
-        private signature: string;
-        selector: string;
-
-        constructor(abi: MethodAbi) {
-            super({ type: 'method', name: abi.name });
-            this.name = abi.name;
-            this.params = [];
-
-            _.each(abi.inputs, (input: DataItem) => {
-                this.params.push(DataTypeFactory.create(input, this));
-            });
-
-            // Compute signature
-            this.signature = `${this.name}(`;
-            _.each(this.params, (param: DataType, i: number) => {
-                this.signature += param.getSignature();
-                if (i < this.params.length - 1) {
-                    this.signature += ',';
-                }
-            });
-            this.signature += ')';
-
-            // Compute selector
-            this.selector = ethUtil.bufferToHex(ethUtil.toBuffer(ethUtil.sha3(this.signature).slice(0, 4)));
-
-            console.log(`--SIGNATURE--\n${this.signature}\n---------\n`);
-            console.log(`--SELECTOR--\n${this.selector}\n---------\n`);
-        }
-
-        public getSignature(): string {
-            return this.signature;
-        }
-
-        public assignValue(args: any[]) {
-            const calldata = new Calldata(this.selector, this.params.length);
-            const params = this.params;
-            const paramQueue = new Queue<DataType>();
-            _.each(params, (param: DataType, i: number) => {
-                try {
-                    param.assignValue(args[i]);
-                } catch (e) {
-                    console.log('Failed to assign to ', param.getDataItem().name);
-                    throw e;
-                }
-                param.bind(calldata, CalldataSection.PARAMS);
-                _.each(param.getChildren(), (child: DataType) => {
-                    paramQueue.push(child);
-                });
-            });
-
-            let param: DataType | undefined = undefined;
-            while ((param = paramQueue.pop()) !== undefined) {
-                param.bind(calldata, CalldataSection.DATA);
-                _.each(param.getChildren(), (child: DataType) => {
-                    paramQueue.push(child);
-                });
-            }
-
-            console.log(calldata);
-
-            this.assignHexValue(calldata.getHexValue());
-
-            //return calldata.getRaw();
-        }
-
-        public encode(args: any[]): string {
-            this.assignValue(args);
-            return this.getHexValue();
-        }
-
-        public isStatic(): boolean {
-            return true;
-        }
-
-        /*
-        encodeOptimized(args: any[]): string {
-            const calldata = new Memory();
-            // Assign values
-            optimizableParams : StaticDataType = [];
-            _.each(this.params, function(args: any[], i: number, param: DataType) {
-                param.assignValue(args[i]);
-                if (param instanceof DynamicDataType) {
-
-                }
-            });
-
-            // Find non-parameter leaves
-
-
-            return '';
-        } */
-
-        /*
-        decode(rawCalldata: string): any[] {
-            const calldata = new Calldata(this.name, this.params.length);
-            calldata.assignRaw(rawCalldata);
-            let args: any[];
-            let params = this.params;
-            _.each(params, function(args: any[], i: number, param: DataType) {
-                param.decodeFromCalldata(calldata);
-                args.push(param.getValue());
-            });
-
-            return args;
-        }*/
-    }
-}
-
 describe.only('ABI Encoder', () => {
     describe.only('Just a Greg, Eh', () => {
+
+
         it('Crazy ABI', async () => {
-            const method = new AbiEncoder.Method(crazyAbi);
+            const method = new AbiEncoder.Method(AbiSamples.crazyAbi);
             console.log(method.getSignature());
 
             const args = [[new BigNumber(127), new BigNumber(14), new BigNumber(54)],
@@ -1405,20 +129,50 @@ describe.only('ABI Encoder', () => {
             expect(calldata).to.be.equal(expectedCalldata);*/
         });
 
-        it.only('Static Array ABI', async () => {
-            const method = new AbiEncoder.Method(staticArrayAbi);
-            const args = [[new BigNumber(127), new BigNumber(14), new BigNumber(54)]];
+        it.only('Fixed Lenfgth Array / Dynamic Members', async () => {
+            const method = new AbiEncoder.Method(AbiSamples.staticArrayDynamicMembersAbi);
+            const args = [["Brave", "New", "World"]];
             const calldata = method.encode(args);
             console.log(calldata);
             console.log('*'.repeat(40));
             console.log(JSON.stringify(args));
             const expectedCalldata =
+                '0x243a6e6e0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+            expect(calldata).to.be.equal(expectedCalldata);
+        });
+
+        it.only('Unfixed Length Array / Dynamic Members ABI', async () => {
+            const method = new AbiEncoder.Method(AbiSamples.dynamicArrayDynamicMembersAbi);
+            const args = [["Brave", "New", "World"]];
+            const calldata = method.encode(args);
+            console.log(calldata);
+            console.log('*'.repeat(40));
+            console.log(JSON.stringify(args));
+            const expectedCalldata = '0x13e751a900000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+            expect(calldata).to.be.equal(expectedCalldata);
+        });
+
+        it.only('Unfixed Length Array / Static Members ABI', async () => {
+            const method = new AbiEncoder.Method(AbiSamples.dynamicArrayStaticMembersAbi);
+            const args = [[new BigNumber(127), new BigNumber(14), new BigNumber(54)]];
+            const calldata = method.encode(args);
+            const expectedCalldata = '0x4fc8a83300000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000007f000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000036';
+            expect(calldata).to.be.equal(expectedCalldata);
+        });
+
+
+        it.only('Fixed Length Array / Static Members ABI', async () => {
+            const method = new AbiEncoder.Method(AbiSamples.staticArrayAbi);
+            const args = [[new BigNumber(127), new BigNumber(14), new BigNumber(54)]];
+            const calldata = method.encode(args);
+            const expectedCalldata =
                 '0xf68ade72000000000000000000000000000000000000000000000000000000000000007f000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000036';
             expect(calldata).to.be.equal(expectedCalldata);
         });
 
+
         it('Simple ABI 2', async () => {
-            const method = new AbiEncoder.Method(simpleAbi2);
+            const method = new AbiEncoder.Method(AbiSamples.simpleAbi2);
 
             const args = [
                 '0xaf', // e (bytes1)
@@ -1434,14 +188,14 @@ describe.only('ABI Encoder', () => {
         });
 
         it('Yessir', async () => {
-            const method = new AbiEncoder.Method(simpleAbi);
+            const method = new AbiEncoder.Method(AbiSamples.simpleAbi);
             const calldata = method.encode([new BigNumber(5), 'five']);
             console.log(calldata);
             expect(true).to.be.true();
         });
 
         it('Array ABI', async () => {
-            const method = new AbiEncoder.Method(stringAbi);
+            const method = new AbiEncoder.Method(AbiSamples.stringAbi);
             const calldata = method.encode([['five', 'six', 'seven']]);
             console.log(method.getSignature());
             console.log(method.selector);
@@ -1453,7 +207,7 @@ describe.only('ABI Encoder', () => {
         });
 
         it('Object ABI (Array input)', async () => {
-            const method = new AbiEncoder.Method(tupleAbi);
+            const method = new AbiEncoder.Method(AbiSamples.tupleAbi);
             const calldata = method.encode([[new BigNumber(5), 'five']]);
             console.log(method.getSignature());
             console.log(method.selector);
@@ -1465,7 +219,7 @@ describe.only('ABI Encoder', () => {
         });
 
         it('Object ABI (Object input)', async () => {
-            const method = new AbiEncoder.Method(tupleAbi);
+            const method = new AbiEncoder.Method(AbiSamples.tupleAbi);
             const calldata = method.encode([{ someUint: new BigNumber(5), someStr: 'five' }]);
             console.log(method.getSignature());
             console.log(method.selector);
@@ -1477,7 +231,7 @@ describe.only('ABI Encoder', () => {
         });
 
         it.skip('Object ABI (Object input - Missing Key)', async () => {
-            const method = new AbiEncoder.Method(tupleAbi);
+            const method = new AbiEncoder.Method(AbiSamples.tupleAbi);
             const calldata = method.encode([{ someUint: new BigNumber(5) }]);
             console.log(method.getSignature());
             console.log(method.selector);
@@ -1491,7 +245,7 @@ describe.only('ABI Encoder', () => {
         });
 
         it.skip('Object ABI (Object input - Too Many Keys)', async () => {
-            const method = new AbiEncoder.Method(tupleAbi);
+            const method = new AbiEncoder.Method(AbiSamples.tupleAbi);
             const calldata = method.encode([{ someUint: new BigNumber(5), someStr: 'five', unwantedKey: 14 }]);
             console.log(method.getSignature());
             console.log(method.selector);
diff --git a/packages/order-utils/test/abi_samples.ts b/packages/order-utils/test/abi_samples.ts
new file mode 100644
index 000000000..2e7111504
--- /dev/null
+++ b/packages/order-utils/test/abi_samples.ts
@@ -0,0 +1,358 @@
+import { MethodAbi } from 'ethereum-types';
+
+export const simpleAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'greg',
+            type: 'uint256',
+        },
+        {
+            name: 'gregStr',
+            type: 'string',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const stringAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'greg',
+            type: 'string[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const tupleAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+            ],
+            name: 'order',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const staticArrayAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'uint8[3]',
+        }
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const staticArrayDynamicMembersAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'string[3]',
+        }
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const dynamicArrayDynamicMembersAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'string[]',
+        }
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const dynamicArrayStaticMembersAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'uint8[]',
+        }
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const crazyAbi = {
+    constant: false,
+    inputs: [
+        /*{
+            name: 'someUInt256',
+            type: 'uint256',
+        },
+        {
+            name: 'someInt256',
+            type: 'int256',
+        },
+        {
+            name: 'someInt32',
+            type: 'int32',
+        },
+        {
+            name: 'someByte',
+            type: 'byte',
+        },
+        {
+            name: 'someBytes32',
+            type: 'bytes32',
+        },
+        {
+            name: 'someBytes',
+            type: 'bytes',
+        },
+        {
+            name: 'someString',
+            type: 'string',
+        },*/
+        /*{
+            name: 'someAddress',
+            type: 'address',
+        },
+        {
+            name: 'someBool',
+            type: 'bool',
+        },*/
+
+        {
+            name: 'someStaticArray',
+            type: 'uint8[3]',
+        },
+        {
+            name: 'someStaticArrayWithDynamicMembers',
+            type: 'string[2]',
+        },
+        {
+            name: 'someDynamicArrayWithDynamicMembers',
+            type: 'bytes[]',
+        },
+        {
+            name: 'some2DArray',
+            type: 'string[][]',
+        },
+        {
+            name: 'someTuple',
+            type: 'tuple',
+            components: [
+                {
+                    name: 'someUint32',
+                    type: 'uint32',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+            ],
+        },
+        {
+            name: 'someTupleWithDynamicTypes',
+            type: 'tuple',
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+                //{
+                //      name: 'someStrArray',
+                //     type: 'string[]',
+                /// },
+                {
+                    name: 'someBytes',
+                    type: 'bytes',
+                },
+                {
+                    name: 'someAddress',
+                    type: 'address',
+                },
+            ],
+        } /*,
+        {
+            name: 'someArrayOfTuplesWithDynamicTypes',
+            type: 'tuple[]',
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+                {
+                    name: 'someStrArray',
+                    type: 'string[]',
+                },
+                {
+                    name: 'someBytes',
+                    type: 'bytes',
+                },
+                {
+                    name: 'someAddress',
+                    type: 'address',
+                },
+            ],
+        },*/,
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const simpleAbi2 = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someByte',
+            type: 'byte',
+        },
+        {
+            name: 'someBytes32',
+            type: 'bytes32',
+        },
+        {
+            name: 'someBytes',
+            type: 'bytes',
+        },
+        {
+            name: 'someString',
+            type: 'string',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;
+
+export const fillOrderAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'makerAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'takerAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'feeRecipientAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'senderAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'makerAssetAmount',
+                    type: 'uint256',
+                },
+                {
+                    name: 'takerAssetAmount',
+                    type: 'uint256',
+                },
+                {
+                    name: 'makerFee',
+                    type: 'uint256',
+                },
+                {
+                    name: 'takerFee',
+                    type: 'uint256',
+                },
+                {
+                    name: 'expirationTimeSeconds',
+                    type: 'uint256',
+                },
+                {
+                    name: 'salt',
+                    type: 'uint256',
+                },
+                {
+                    name: 'makerAssetData',
+                    type: 'bytes',
+                },
+                {
+                    name: 'takerAssetData',
+                    type: 'bytes',
+                },
+            ],
+            name: 'order',
+            type: 'tuple',
+        },
+        {
+            name: 'takerAssetFillAmount',
+            type: 'uint256',
+        },
+        {
+            name: 'salt',
+            type: 'uint256',
+        },
+        {
+            name: 'orderSignature',
+            type: 'bytes',
+        },
+        {
+            name: 'takerSignature',
+            type: 'bytes',
+        },
+    ],
+    name: 'fillOrder',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+} as MethodAbi;