1 files changed, 64 insertions, 0 deletions
diff --git a/packages/utils/src/abi_encoder/evm_data_types/array.ts b/packages/utils/src/abi_encoder/evm_data_types/array.ts
new file mode 100644
index 000000000..7595cb667
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/array.ts
@@ -0,0 +1,64 @@
+import { DataItem } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractSetDataType } from '../abstract_data_types/types/set';
+import { constants } from '../utils/constants';
+
+export class ArrayDataType extends AbstractSetDataType {
+    private static readonly _MATCHER = RegExp('^(.+)\\[([0-9]*)\\]$');
+    private readonly _arraySignature: string;
+    private readonly _elementType: string;
+
+    public static matchType(type: string): boolean {
+        return ArrayDataType._MATCHER.test(type);
+    }
+
+    private static _decodeElementTypeAndLengthFromType(type: string): [string, undefined | number] {
+        const matches = ArrayDataType._MATCHER.exec(type);
+        if (_.isNull(matches) || matches.length !== 3) {
+            throw new Error(`Could not parse array: ${type}`);
+        } else if (_.isUndefined(matches[1])) {
+            throw new Error(`Could not parse array type: ${type}`);
+        } else if (_.isUndefined(matches[2])) {
+            throw new Error(`Could not parse array length: ${type}`);
+        }
+        const arrayElementType = matches[1];
+        const arrayLength = _.isEmpty(matches[2]) ? undefined : parseInt(matches[2], constants.DEC_BASE);
+        return [arrayElementType, arrayLength];
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        // Construct parent
+        const isArray = true;
+        const [arrayElementType, arrayLength] = ArrayDataType._decodeElementTypeAndLengthFromType(dataItem.type);
+        super(dataItem, dataTypeFactory, isArray, arrayLength, arrayElementType);
+        // Set array properties
+        this._elementType = arrayElementType;
+        this._arraySignature = this._computeSignature();
+    }
+
+    public getSignature(): string {
+        return this._arraySignature;
+    }
+
+    private _computeSignature(): string {
+        // Compute signature for a single array element
+        const elementDataItem: DataItem = {
+            type: this._elementType,
+            name: 'N/A',
+        };
+        const elementComponents = this.getDataItem().components;
+        if (!_.isUndefined(elementComponents)) {
+            elementDataItem.components = elementComponents;
+        }
+        const elementDataType = this.getFactory().create(elementDataItem);
+        const elementSignature = elementDataType.getSignature();
+        // Construct signature for array of type `element`
+        if (_.isUndefined(this._arrayLength)) {
+            return `${elementSignature}[]`;
+        } else {
+            return `${elementSignature}[${this._arrayLength}]`;
+        }
+    }
+}