// Copyright 2023 The Bazel 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
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package com.google.devtools.build.lib.skyframe;

import com.google.devtools.build.lib.cmdline.PackageIdentifier;
import com.google.devtools.build.lib.packages.Package;
import javax.annotation.Nullable;

/**
 * Looks up previously loaded packages.
 *
 * <p>Used by {@link ConfiguredTargetFunction} to lookup packages of dependencies.
 */
public interface PrerequisitePackageFunction {

  /** Directly retrieves packages of dependencies from Skyframe without adding a dependency edge. */
  @Nullable // Null if the package not available.
  Package getExistingPackage(PackageIdentifier id) throws InterruptedException;
}