[pull] main from expo:main

packages/expo-file-system/CHANGELOG.md

@@ -13,6 +13,8 @@
 
 ### 💡 Others
 
+- Improve read/write performance on Android by applying `withContext(Dispatchers.IO)` when possible. ([#46376](https://github.com/expo/expo/pull/46376) by [@wh201906](https://github.com/wh201906))
+
 ## 56.0.7 — 2026-05-20
 
 ### 🛠 Breaking changes

packages/expo-file-system/android/src/main/java/expo/modules/filesystem/FileSystemFile.kt

@@ -5,8 +5,8 @@ import android.util.Base64
 import expo.modules.filesystem.unifiedfile.JavaFile
 import expo.modules.filesystem.unifiedfile.SAFDocumentFile
 import expo.modules.kotlin.exception.Exceptions
+import expo.modules.kotlin.jni.NativeArrayBuffer
 import expo.modules.kotlin.services.FilePermissionService
-import expo.modules.kotlin.typedarray.TypedArray
 import java.io.FileOutputStream
 import java.security.MessageDigest
 
@@ -84,15 +84,15 @@ class FileSystemFile(uri: Uri) : FileSystemPath(uri) {
     }
   }
 
-  fun write(content: TypedArray, append: Boolean = false) {
+  fun write(content: NativeArrayBuffer, append: Boolean = false) {
     validateType()
     validatePermission(FilePermissionService.Permission.WRITE)
     if (!exists) {
       create()
     }
     if (uri.isContentUri) {
       file.outputStream(append).use { outputStream ->
-        val array = ByteArray(content.length)
+        val array = ByteArray(content.size())
         content.toDirectBuffer().get(array)
         outputStream.write(array)
       }

packages/expo-file-system/android/src/main/java/expo/modules/filesystem/FileSystemModule.kt

@@ -8,12 +8,14 @@ import androidx.annotation.RequiresApi
 import expo.modules.kotlin.activityresult.AppContextActivityResultLauncher
 import expo.modules.kotlin.exception.Exceptions
 import expo.modules.kotlin.functions.Coroutine
+import expo.modules.kotlin.jni.NativeArrayBuffer
 import expo.modules.kotlin.modules.Module
 import expo.modules.kotlin.modules.ModuleDefinition
 import expo.modules.kotlin.services.FilePermissionService
-import expo.modules.kotlin.typedarray.TypedArray
 import expo.modules.kotlin.types.Either
+import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.withContext
 import java.io.File
 import java.net.URI
 
@@ -31,7 +33,7 @@ class FileSystemModule : Module() {
 
   private fun writeToFile(
     file: FileSystemFile,
-    content: Either<String, TypedArray>,
+    content: Either<String, NativeArrayBuffer>,
     options: WriteOptions?
   ) {
     val append = options?.append ?: false
@@ -43,8 +45,8 @@ class FileSystemModule : Module() {
           file.write(it, append)
         }
       }
-    } else if (content.`is`(TypedArray::class)) {
-      content.get(TypedArray::class).let {
+    } else if (content.`is`(NativeArrayBuffer::class)) {
+      content.get(NativeArrayBuffer::class).let {
         file.write(it, append)
       }
     }
@@ -159,32 +161,40 @@ class FileSystemModule : Module() {
         file.create(options ?: CreateOptions())
       }
 
-      AsyncFunction("write") Coroutine { file: FileSystemFile, content: Either<String, TypedArray>, options: WriteOptions? ->
-        writeToFile(file, content, options)
+      AsyncFunction("write") Coroutine { file: FileSystemFile, content: Either<String, NativeArrayBuffer>, options: WriteOptions? ->
+        withContext(Dispatchers.IO) {
+          writeToFile(file, content, options)
+        }
       }
 
-      Function("writeSync") { file: FileSystemFile, content: Either<String, TypedArray>, options: WriteOptions? ->
+      Function("writeSync") { file: FileSystemFile, content: Either<String, NativeArrayBuffer>, options: WriteOptions? ->
         writeToFile(file, content, options)
       }
 
-      AsyncFunction("text") { file: FileSystemFile ->
-        file.text()
+      AsyncFunction("text") Coroutine { file: FileSystemFile ->
+        withContext(Dispatchers.IO) {
+          file.text()
+        }
       }
 
       Function("textSync") { file: FileSystemFile ->
         file.text()
       }
 
-      AsyncFunction("base64") { file: FileSystemFile ->
-        file.base64()
+      AsyncFunction("base64") Coroutine { file: FileSystemFile ->
+        withContext(Dispatchers.IO) {
+          file.base64()
+        }
       }
 
       Function("base64Sync") { file: FileSystemFile ->
         file.base64()
       }
 
-      AsyncFunction("bytes") { file: FileSystemFile ->
-        file.bytes()
+      AsyncFunction("bytes") Coroutine { file: FileSystemFile ->
+        withContext(Dispatchers.IO) {
+          file.bytes()
+        }
       }
 
       Function("bytesSync") { file: FileSystemFile ->

packages/expo-file-system/ios/FileSystemFile.swift

@@ -105,9 +105,11 @@ internal final class FileSystemFile: FileSystemPath {
   }
 
   // TODO: blob support
-  func write(_ content: TypedArray, append: Bool = false) throws {
+  func write(_ content: NativeArrayBuffer, append: Bool = false) throws {
     try withCorrectTypeAndScopedAccess(permission: .write) {
-      let data = Data(bytes: content.rawPointer, count: content.byteLength)
+      let data = content.withUnsafeBytes { rawBuffer in
+        Data(rawBuffer)
+      }
       if append {
         try writeAppending(data)
       } else {

packages/expo-file-system/ios/FileSystemModule.swift

@@ -36,7 +36,7 @@ public final class FileSystemModule: Module {
 
   private func writeToFile(
     _ file: FileSystemFile,
-    content: Either<String, TypedArray>,
+    content: Either<String, NativeArrayBuffer>,
     options: WriteOptions?
   ) throws {
     let append = options?.append ?? false
@@ -49,7 +49,7 @@ public final class FileSystemModule: Module {
       } else {
         try file.write(content, append: append)
       }
-    } else if let content: TypedArray = content.get() {
+    } else if let content: NativeArrayBuffer = content.get() {
       try file.write(content, append: append)
     }
   }
@@ -194,11 +194,11 @@ public final class FileSystemModule: Module {
         return try file.info(options: options ?? InfoOptions())
       }
 
-      AsyncFunction("write") { (file: FileSystemFile, content: Either<String, TypedArray>, options: WriteOptions?) in
+      AsyncFunction("write") { (file: FileSystemFile, content: Either<String, NativeArrayBuffer>, options: WriteOptions?) in
         try writeToFile(file, content: content, options: options)
       }
 
-      Function("writeSync") { (file: FileSystemFile, content: Either<String, TypedArray>, options: WriteOptions?) in
+      Function("writeSync") { (file: FileSystemFile, content: Either<String, NativeArrayBuffer>, options: WriteOptions?) in
         try writeToFile(file, content: content, options: options)
       }
 

packages/expo-file-system/mocks/FileSystem.ts

@@ -247,7 +247,7 @@ export class FileSystemFile {
   }
 
   writeSync(
-    content: string | Uint8Array,
+    content: string | Uint8Array | ArrayBuffer,
     options: { append?: boolean; encoding?: 'utf8' | 'base64' } = {}
   ): void {
     assertParent(this.uri, false);
@@ -281,7 +281,7 @@ export class FileSystemFile {
   }
 
   async write(
-    content: string | Uint8Array,
+    content: string | Uint8Array | ArrayBuffer,
     options: { append?: boolean; encoding?: 'utf8' | 'base64' } = {}
   ): Promise<void> {
     this.writeSync(content, options);

packages/expo-file-system/src/__tests__/FileSystem-test.native.ts

@@ -236,6 +236,14 @@ describe('expo-file-system behavioral mock', () => {
     await expect(file.bytes()).resolves.toEqual(payload);
   });
 
+  it('File.writeSync(ArrayBuffer) and File.bytes() roundtrip byte-for-byte', async () => {
+    const file = new File(Paths.cache, 'bin-buffer.dat');
+    const payload = Uint8Array.from([6, 7, 8, 9]).buffer;
+    file.writeSync(payload);
+    expect(Array.from(file.bytesSync())).toEqual([6, 7, 8, 9]);
+    await expect(file.bytes()).resolves.toEqual(new Uint8Array(payload));
+  });
+
   it('File.writeSync with append option appends to existing bytes', () => {
     const file = new File(Paths.cache, 'log.txt');
     file.writeSync('a');