/** A single file operation recorded by the virtual tree. */
export type FileChange = {
    path: string;
    type: 'CREATE' | 'UPDATE';
    content: string;
};
/** Abstraction over `node:fs` used by the virtual tree for disk I/O. */
export type FileSystemAdapter = {
    readFile: (path: string, encoding: 'utf8') => Promise<string>;
    writeFile: (path: string, content: string) => Promise<void>;
    exists: (path: string) => Promise<boolean>;
    mkdir: (path: string, options: {
        recursive: true;
    }) => Promise<string | undefined>;
    unlink: (path: string) => Promise<void>;
};
/** Virtual file system that buffers writes in memory until flushed to disk. */
export type Tree = {
    root: string;
    exists: (filePath: string) => Promise<boolean>;
    read: (filePath: string) => Promise<string | null>;
    write: (filePath: string, content: string) => Promise<void>;
    listChanges: () => FileChange[];
    flush: () => Promise<void>;
};
/** Internal pending-entry shape held by the virtual tree. */
export type PendingEntry = {
    content: string;
    type: 'CREATE' | 'UPDATE';
    original: string | null;
};