feat: Add filename util getUniqueName to generate a unique name

__tests__/utils/filename.spec.ts

@@ -3,6 +3,7 @@
  * SPDX-License-Identifier: AGPL-3.0-or-later or LGPL-3.0-or-later
  */
 import { describe, it, expect, beforeEach, vi } from 'vitest'
+import { getUniqueName } from '../../lib/index'
 
 describe('isFilenameValid', () => {
 	beforeEach(() => {
@@ -42,3 +43,43 @@ describe('isFilenameValid', () => {
 		expect(isFilenameValid('.filepart')).toBe(false)
 	})
 })
+
+describe('getUniqueName', () => {
+	it('returns the same name if unique', () => {
+		const name = 'file.txt'
+		const others = ['other.png', 'folder']
+
+		expect(getUniqueName(name, others)).toBe(name)
+	})
+
+	it('adds the index as a suffix by default', () => {
+		const name = 'file.txt'
+		const others = ['file.txt', 'folder']
+
+		expect(getUniqueName(name, others)).toBe('file (1).txt')
+	})
+
+	it('increases the index if needed', () => {
+		const name = 'file.txt'
+		const others = ['file.txt', 'file (1).txt']
+
+		expect(getUniqueName(name, others)).toBe('file (2).txt')
+	})
+
+	it('uses custom suffix if provided', () => {
+		const name = 'file.txt'
+		const others = ['file.txt', 'folder']
+		const suffix = vi.fn((i) => `[${i}]`)
+
+		expect(getUniqueName(name, others, { suffix })).toBe('file [1].txt')
+		expect(suffix).toBeCalledTimes(1)
+		expect(suffix).toBeCalledWith(1)
+	})
+
+	it('can ignore the file extension', () => {
+		const name = 'folder.with.dot'
+		const others = ['folder', 'folder.with.dot', 'file.txt']
+
+		expect(getUniqueName(name, others, { ignoreFileExtension: true })).toBe('folder.with.dot (1)')
+	})
+})

lib/index.ts

@@ -20,7 +20,7 @@ export { File } from './files/file'
 export { Folder } from './files/folder'
 export { Node, NodeStatus } from './files/node'
 
-export { isFilenameValid } from './utils/filename'
+export { isFilenameValid, getUniqueName } from './utils/filename'
 export { formatFileSize, parseFileSize } from './utils/fileSize'
 export { orderBy } from './utils/sorting'
 export { sortNodes, FilesSortingMode, type FilesSortingOptions } from './utils/fileSorting'

lib/utils/filename.ts

@@ -3,6 +3,8 @@
  * SPDX-License-Identifier: AGPL-3.0-or-later or LGPL-3.0-or-later
  */
 
+import { basename, extname } from 'path'
+
 const forbiddenCharacters = window._oc_config?.forbidden_filenames_characters ?? ['/', '\\']
 const forbiddenFilenameRegex = window._oc_config?.blacklist_files_regex ? new RegExp(window._oc_config.blacklist_files_regex) : null
 
@@ -23,3 +25,43 @@ export function isFilenameValid(filename: string): boolean {
 	// in Nextcloud 30 also check forbidden file extensions and file prefixes
 	return true
 }
+
+interface UniqueNameOptions {
+	/**
+	 * A function that takes an index and returns a suffix to add to the file name, defaults to '(index)'
+	 * @param index The current index to add
+	 */
+	suffix?: (index: number) => string
+	/**
+	 * Set to true to ignore the file extension when adding the suffix (when getting a unique directory name)
+	 */
+	ignoreFileExtension?: boolean
+}
+
+/**
+ * Create an unique file name
+ * @param name The initial name to use
+ * @param otherNames Other names that are already used
+ * @param options Optional parameters for tuning the behavior
+ * @return {string} Either the initial name, if unique, or the name with the suffix so that the name is unique
+ */
+export function getUniqueName(
+	name: string,
+	otherNames: string[],
+	options?: UniqueNameOptions,
+): string {
+	const opts = {
+		suffix: (n: number) => `(${n})`,
+		ignoreFileExtension: false,
+		...options,
+	}
+
+	let newName = name
+	let i = 1
+	while (otherNames.includes(newName)) {
+		const ext = opts.ignoreFileExtension ? '' : extname(name)
+		const base = basename(name, ext)
+		newName = `${base} ${opts.suffix(i++)}${ext}`
+	}
+	return newName
+}