chore!: remove deprecated filename validation fallbacks for Nextcloud 29 and below

CHANGELOG.md

@@ -6,6 +6,12 @@
 
 All notable changes to this project will be documented in this file.
 
+## 4.0.0 (UNRELEASED)
+### 📝 Notes
+* The support for Nextcloud versions below 30 has been removed,
+  this means some functions like filename validation will now only
+  work with the capabilities provided by Nextcloud 30 or newer.
+
 ## 4.0.0-beta.1 - 2025-11-27
 ### 🐛 Fixed bugs
 * fix: actions type exports by @skjnldsv in https://github.com/nextcloud-libraries/nextcloud-files/pull/1381

README.md

@@ -13,6 +13,15 @@ This library provides three kinds of utils:
 2. Geneal purpose function related to files or folders, like filename validation.
 3. Functions and classes to interact with the Nextcloud **files** app, like registering a new view or a file action.
 
+## Compatibility
+
+| `@nextcloud/files` version | Supported | Nextcloud version |
+|----------------------------|-----------|-------------------|
+|                        4.x |        ✅ |               30+ |
+|                        3.x |        ✅ |               26+ |
+|                        2.x |        ❌ |             23-25 |
+|                        1.x |        ❌ |             20-22 |
+
 ## Usage examples
 
 ### Files app

__tests__/utils/filename-validation.spec.ts

@@ -49,19 +49,6 @@ describe('validateFilename', () => {
 		expect(() => validateFilename('.htaccess')).toThrowError(InvalidFilenameError)
 	})
 
-	it('has fallback invalid extension', async () => {
-		expect(() => validateFilename('file.txt.part')).toThrowError(InvalidFilenameError)
-		expect(() => validateFilename('file.txt.filepart')).toThrowError(InvalidFilenameError)
-	})
-
-	// Nextcloud 29
-	it('fallback fetching forbidden characters from oc config', async () => {
-		window._oc_config = { forbidden_filenames_characters: ['=', '?'] }
-		expect(() => validateFilename('foo.bar')).not.toThrow()
-		expect(() => validateFilename('foo=bar')).toThrowError(InvalidFilenameError)
-		expect(() => validateFilename('foo?bar')).toThrowError(InvalidFilenameError)
-	})
-
 	// Nextcloud 30+
 	it('fetches forbidden characters from capabilities', async () => {
 		nextcloudCapabilities.getCapabilities.mockImplementation(() => ({ files: { forbidden_filename_characters: ['=', '?'] } }))
@@ -136,14 +123,16 @@ describe('validateFilename', () => {
 	})
 
 	it('sets error properties correctly on invalid extension', async () => {
+		nextcloudCapabilities.getCapabilities.mockImplementation(() => ({ files: { forbidden_filename_extensions: ['.txt'] } }))
+
 		try {
-			validateFilename('file.part')
+			validateFilename('file.txt')
 			expect(true, 'should not be reached').toBeFalsy()
 		} catch (error) {
 			expect(error).toBeInstanceOf(InvalidFilenameError)
 			expect((error as InvalidFilenameError).reason).toBe(InvalidFilenameErrorReason.Extension)
-			expect((error as InvalidFilenameError).segment).toBe('.part')
-			expect((error as InvalidFilenameError).filename).toBe('file.part')
+			expect((error as InvalidFilenameError).segment).toBe('.txt')
+			expect((error as InvalidFilenameError).filename).toBe('file.txt')
 		}
 	})
 

lib/utils/filename-validation.ts

@@ -78,7 +78,7 @@ export function validateFilename(filename: string): void {
 
 	// Handle forbidden characters
 	// This needs to be done first as the other checks are case insensitive!
-	const forbiddenCharacters = capabilities.forbidden_filename_characters ?? window._oc_config?.forbidden_filenames_characters ?? ['/', '\\']
+	const forbiddenCharacters = capabilities.forbidden_filename_characters ?? ['/', '\\']
 	for (const character of forbiddenCharacters) {
 		if (filename.includes(character)) {
 			throw new InvalidFilenameError({ segment: character, reason: InvalidFilenameErrorReason.Character, filename })
@@ -102,9 +102,7 @@ export function validateFilename(filename: string): void {
 		throw new InvalidFilenameError({ filename, segment: basename, reason: InvalidFilenameErrorReason.ReservedName })
 	}
 
-	// The legacy 'blacklist_files_regex' was hardcoded to the extension '.part' and '.filepart'
-	// So if the new (Nextcloud 30) capability is not awailable then we fallback to that
-	const forbiddenFilenameExtensions = capabilities.forbidden_filename_extensions ?? ['.part', '.filepart']
+	const forbiddenFilenameExtensions = capabilities.forbidden_filename_extensions ?? []
 	for (const extension of forbiddenFilenameExtensions) {
 		if (filename.length > extension.length && filename.endsWith(extension)) {
 			throw new InvalidFilenameError({ segment: extension, reason: InvalidFilenameErrorReason.Extension, filename })
@@ -114,7 +112,7 @@ export function validateFilename(filename: string): void {
 
 /**
  * Check the validity of a filename
- * This is a convinient wrapper for `checkFilenameValidity` to only return a boolean for the valid
+ * This is a convenient wrapper for `checkFilenameValidity` to only return a boolean for the valid
  * @param filename Filename to check validity
  */
 export function isFilenameValid(filename: string): boolean {

lib/window.d.ts

@@ -33,8 +33,6 @@ declare global {
 
 		_oc_config?: {
 			forbidden_filenames_characters: string[]
-			/** @deprecated */
-			blacklist_files_regex?: string
 		}
 	}
 }