import { Tree } from '@angular-devkit/schematics';
import * as ts from 'typescript';
export declare type FakeReadFileFn = (fileName: string) => string | null;
/**
 * Creates a TypeScript program instance for a TypeScript project within
 * the virtual file system tree.
 * @param tree Virtual file system tree that contains the source files.
 * @param tsconfigPath Virtual file system path that resolves to the TypeScript project.
 * @param basePath Base path for the virtual file system tree.
 * @param fakeFileRead Optional file reader function. Can be used to overwrite files in
 *   the TypeScript program, or to add in-memory files (e.g. to add global types).
 * @param additionalFiles Additional file paths that should be added to the program.
 */
export declare function createMigrationProgram(tree: Tree, tsconfigPath: string, basePath: string, fakeFileRead?: FakeReadFileFn, additionalFiles?: Array<string>): any;
export declare function createMigrationCompilerHost(tree: Tree, options: ts.CompilerOptions, basePath: string, fakeRead?: FakeReadFileFn): ts.CompilerHost;