1 files changed, 33 insertions, 25 deletions

diff --git a/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts b/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
index 9a2a99ec7..afa9afdf2 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
@@ -11,7 +11,6 @@ export class StaticBytes extends PayloadDataType {
     private static readonly _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))$',
     );
-
     private static readonly _DEFAULT_WIDTH = 1;
     private readonly _width: number;
 
@@ -19,16 +18,20 @@ export class StaticBytes extends PayloadDataType {
         return StaticBytes._matcher.test(type);
     }
 
+    private static _decodeWidthFromType(type: string): number {
+        const matches = StaticBytes._matcher.exec(type);
+        const width = (matches !== null && matches.length === 3 && matches[2] !== undefined)
+            ? parseInt(matches[2], Constants.DEC_BASE)
+            : StaticBytes._DEFAULT_WIDTH;
+        return width;
+    }
+
     public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
         super(dataItem, dataTypeFactory, StaticBytes._SIZE_KNOWN_AT_COMPILE_TIME);
-        const matches = StaticBytes._matcher.exec(dataItem.type);
         if (!StaticBytes.matchType(dataItem.type)) {
-            throw new Error(`Tried to instantiate Byte with bad input: ${dataItem}`);
+            throw new Error(`Tried to instantiate Static Bytes with bad input: ${dataItem}`);
         }
-        this._width =
-            matches !== null && matches.length === 3 && matches[2] !== undefined
-                ? parseInt(matches[2], Constants.DEC_BASE)
-                : StaticBytes._DEFAULT_WIDTH;
+        this._width = StaticBytes._decodeWidthFromType(dataItem.type);
     }
 
     public getSignature(): string {
@@ -37,11 +40,30 @@ export class StaticBytes extends PayloadDataType {
     }
 
     public encodeValue(value: string | Buffer): Buffer {
-        // Sanity check if string
-        if (typeof value === 'string' && !value.startsWith('0x')) {
-            throw new Error(`Tried to encode non-hex value. Value must inlcude '0x' prefix.`);
+        // 1/2 Convert value into a buffer and do bounds checking
+        this._sanityCheckValue(value);
+        const valueBuf = ethUtil.toBuffer(value);
+        // 2/2 Store value as hex
+        const valuePadded = ethUtil.setLengthRight(valueBuf, Constants.EVM_WORD_WIDTH_IN_BYTES);
+        return valuePadded;
+    }
+
+    public decodeValue(calldata: RawCalldata): string {
+        const valueBufPadded = calldata.popWord();
+        const valueBuf = valueBufPadded.slice(0, this._width);
+        const value = ethUtil.bufferToHex(valueBuf);
+        this._sanityCheckValue(value);
+        return value;
+    }
+    
+    private _sanityCheckValue(value: string | Buffer): void {
+        if (typeof value === 'string') {
+            if (!value.startsWith('0x')) {
+                throw new Error(`Tried to encode non-hex value. Value must inlcude '0x' prefix.`);
+            } else if (value.length % 2 !== 0) {
+                throw new Error(`Tried to assign ${value}, which is contains a half-byte. Use full bytes only.`);
+            }
         }
-        // Convert value into a buffer and do bounds checking
         const valueBuf = ethUtil.toBuffer(value);
         if (valueBuf.byteLength > this._width) {
             throw new Error(
@@ -49,20 +71,6 @@ export class StaticBytes extends PayloadDataType {
                     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);
-        return paddedValue;
-    }
-
-    public decodeValue(calldata: RawCalldata): string {
-        const paddedValueBuf = calldata.popWord();
-        const valueBuf = paddedValueBuf.slice(0, this._width);
-        const value = ethUtil.bufferToHex(valueBuf);
-        return value;
     }
 }