Extract common utilities to a module.

Author: microbit-carlos

src/__tests__/upyhex.spec.ts renamed to src/__tests__/appended-script.spec.ts

@@ -2,6 +2,7 @@
  * Module to add and remove Python scripts into and from a MicroPython hex.
  */
 import MemoryMap from 'nrf-intel-hex';
+import { bytesToStr, strToBytes } from './common';
 
 const enum UserCodeBlock {
   /** User script located at specific flash address. */
@@ -27,34 +28,6 @@ const enum UserCodeBlock {
  */
 const HEX_INSERTION_POINT = ':::::::::::::::::::::::::::::::::::::::::::\n';
 
-/**
- * Converts a string into a byte array of characters.
- * TODO: Update to encode to UTF-8 correctly.
- * @param str - String to convert to bytes.
- * @returns A byte array with the encoded data.
- */
-function strToBytes(str: string): Uint8Array {
-  const data: Uint8Array = new Uint8Array(str.length);
-  for (let i: number = 0; i < str.length; i++) {
-    // TODO: This will only keep the LSB from the UTF-16 code points
-    data[i] = str.charCodeAt(i);
-  }
-  return data;
-}
-
-/**
- * Converts a byte array into a string of characters.
- * TODO: This currently only deals with single byte characters, so needs to
- *       be expanded to support UTF-8 characters longer than 1 byte.
- * @param byteArray - Array of bytes to convert.
- * @returns String output from the conversion.
- */
-function bytesToStr(byteArray: Uint8Array): string {
-  const result: string[] = [];
-  byteArray.forEach((element) => result.push(String.fromCharCode(element)));
-  return result.join('');
-}
-
 /**
  * Removes the old insertion line the input Intel Hex string contains it.
  * @param intelHex String with the intel hex lines.

src/appended-script.ts

@@ -0,0 +1,33 @@
+/**
+ * General utilities.
+ */
+
+/**
+ * Converts a string into a byte array of characters.
+ * TODO: Update to encode to UTF-8 correctly.
+ * @param str - String to convert to bytes.
+ * @returns A byte array with the encoded data.
+ */
+function strToBytes(str: string): Uint8Array {
+  const data: Uint8Array = new Uint8Array(str.length);
+  for (let i: number = 0; i < str.length; i++) {
+    // TODO: This will only keep the LSB from the UTF-16 code points
+    data[i] = str.charCodeAt(i);
+  }
+  return data;
+}
+
+/**
+ * Converts a byte array into a string of characters.
+ * TODO: This currently only deals with single byte characters, so needs to
+ *       be expanded to support UTF-8 characters longer than 1 byte.
+ * @param byteArray - Array of bytes to convert.
+ * @returns String output from the conversion.
+ */
+function bytesToStr(byteArray: Uint8Array): string {
+  const result: string[] = [];
+  byteArray.forEach((element) => result.push(String.fromCharCode(element)));
+  return result.join('');
+}
+
+export { strToBytes, bytesToStr };