feature: directly write to fs

src/shims-fs.d.ts

@@ -0,0 +1,51 @@
+export interface FileSystemGetFileOptions {
+    create?: boolean
+}
+
+interface FileSystemCreateWritableOptions {
+    keepExistingData?: boolean
+}
+
+interface FileSystemFileHandle {
+    getFile(): Promise<File>;
+
+    createWritable(options?: FileSystemCreateWritableOptions): Promise<FileSystemWritableFileStream>
+}
+
+enum WriteCommandType {
+    write = "write",
+    seek = "seek",
+    truncate = "truncate",
+}
+
+interface WriteParams {
+    type: WriteCommandType
+    size?: number
+    position?: number
+    data: BufferSource | Blob | string
+}
+
+type FileSystemWriteChunkType = BufferSource | Blob | string | WriteParams
+
+interface FileSystemWritableFileStream extends WritableStream {
+    write(data: FileSystemWriteChunkType): Promise<undefined>
+
+    seek(position: number): Promise<undefined>
+
+    truncate(size: number): Promise<undefined>
+
+    close(): Promise<undefined> // should be implemented in WritableStream
+}
+
+export declare interface FileSystemDirectoryHandle {
+    getFileHandle(name: string, options?: FileSystemGetFileOptions): Promise<FileSystemFileHandle>
+}
+
+declare global {
+    interface Window {
+        FileSystemDirectoryHandle
+
+        showDirectoryPicker?(): Promise<FileSystemDirectoryHandle>
+    }
+}
+