build/lib/src/generate/run_builder.dart

// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
import 'dart:async';

import 'package:logging/logging.dart';

import '../analyzer/resolver.dart';
import '../asset/id.dart';
import '../asset/reader.dart';
import '../asset/writer.dart';
import '../builder/build_step.dart';
import '../builder/build_step_impl.dart';
import '../builder/builder.dart';
import '../builder/logging.dart';
import '../resource/resource.dart';
import 'expected_outputs.dart';

/// Run [builder] with each asset in [inputs] as the primary input.
///
/// Builds for all inputs are run asynchronously and ordering is not guaranteed.
/// The [log] instance inside the builds will be scoped to [logger] which is
/// defaulted to a [Logger] name 'runBuilder'.
///
/// If a [resourceManager] is provided it will be used and it will not be
/// automatically disposed of (its up to the caller to dispose of it later). If
/// one is not provided then one will be created and disposed at the end of
/// this function call.
Future<void> runBuilder(Builder builder, Iterable<AssetId> inputs,
    AssetReader reader, AssetWriter writer, Resolvers resolvers,
    {Logger logger,
    ResourceManager resourceManager,
    String rootPackage,
    StageTracker stageTracker = NoOpStageTracker.instance}) async {
  var shouldDisposeResourceManager = resourceManager == null;
  resourceManager ??= ResourceManager();
  logger ??= Logger('runBuilder');
  //TODO(nbosch) check overlapping outputs?
  Future<void> buildForInput(AssetId input) async {
    var outputs = expectedOutputs(builder, input);
    if (outputs.isEmpty) return;
    var buildStep = BuildStepImpl(input, outputs, reader, writer,
        rootPackage ?? input.package, resolvers, resourceManager, stageTracker);
    try {
      await builder.build(buildStep);
    } finally {
      await buildStep.complete();
    }
  }

  await scopeLogAsync(() => Future.wait(inputs.map(buildForInput)), logger);

  if (shouldDisposeResourceManager) {
    await resourceManager.disposeAll();
    await resourceManager.beforeExit();
  }
}