refactor(utils): expose formatExt as utility

Signed-off-by: Lexus Drumgold <[email protected]>

package.json

@@ -42,8 +42,8 @@
   "types": "./dist/index.d.mts",
   "typesVersions": {
     "*": {
-      "./utils/*": [
-        "./dist/utils/*.d.mts"
+      "./utils": [
+        "./dist/utils/index.d.mts"
       ]
     }
   },

src/utils/__tests__/format-ext.spec.ts

@@ -0,0 +1,27 @@
+/**
+ * @file Unit Tests - formatExt
+ * @module pathe/utils/tests/unit/formatExt
+ */
+
+import type { Ext } from '#src/types'
+import testSubject from '../format-ext'
+
+describe('unit:utils/formatExt', () => {
+  let ext: Ext
+
+  beforeEach(() => {
+    ext = '.mjs'
+  })
+
+  it('should return empty string if ext is empty string', () => {
+    expect(testSubject('')).to.equal('')
+  })
+
+  it('should return ext without modifications if ext starts with dot', () => {
+    expect(testSubject(ext)).to.equal(ext)
+  })
+
+  it('should return formatted file extension', () => {
+    expect(testSubject(ext.slice(1))).to.equal(ext)
+  })
+})

src/utils/format-ext.ts

@@ -0,0 +1,23 @@
+/**
+ * @file Utilities - formatExt
+ * @module pathe/utils/formatExt
+ */
+
+import type { Ext } from '#src/types'
+import type { EmptyString } from '@flex-development/tutils'
+
+/**
+ * Formats a file extension.
+ *
+ * This includes:
+ *
+ * - Prepending a `.` (dot) character if not already present
+ *
+ * @param {string} [ext=''] - File extension to format
+ * @return {EmptyString | Ext} Formatted file extension or empty string
+ */
+const formatExt = (ext: string = ''): EmptyString | Ext => {
+  return ext.trim().replace(/^([^.])/, '.$1') as EmptyString | Ext
+}
+
+export default formatExt

src/utils/index.ts

@@ -0,0 +1,6 @@
+/**
+ * @file Entry Point - Utilities
+ * @module pathe/utils
+ */
+
+export { default as formatExt } from './format-ext'