/**
 * Copyright 2019 The AMP HTML Authors. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import SourceMapTree from './source-map-tree';
import type { SourceMapInput, SourceMapLoader } from './types';
/**
 * Recursively builds a tree structure out of sourcemap files, with each node
 * being either an `OriginalSource` "leaf" or a `SourceMapTree` composed of
 * `OriginalSource`s and `SourceMapTree`s.
 *
 * Every sourcemap is composed of a collection of source files and mappings
 * into locations of those source files. When we generate a `SourceMapTree` for
 * the sourcemap, we attempt to load each source file's own sourcemap. If it
 * does not have an associated sourcemap, it is considered an original,
 * unmodified source file.
 */
export default function buildSourceMapTree(input: SourceMapInput | SourceMapInput[], loader: SourceMapLoader, relativeRoot?: string): SourceMapTree;