Rename several classes in barback.

pkg/barback/lib/src/asset_graph.dart

Index: pkg/barback/lib/src/asset_graph.dart
diff --git a/pkg/barback/lib/src/asset_graph.dart b/pkg/barback/lib/src/asset_graph.dart
deleted file mode 100644
index 835e9a4a06144cabb38c9487f63025fd8cd6c5ac..0000000000000000000000000000000000000000
--- a/pkg/barback/lib/src/asset_graph.dart
+++ /dev/null
@@ -1,291 +0,0 @@
-// Copyright (c) 2013, 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.
-
-library barback.asset_graph;
-
-import 'dart:async';
-import 'dart:collection';
-
-import 'asset.dart';
-import 'asset_id.dart';
-import 'asset_graph_manager.dart';
-import 'asset_provider.dart';
-import 'asset_set.dart';
-import 'errors.dart';
-import 'change_batch.dart';
-import 'phase.dart';
-import 'transformer.dart';
-import 'utils.dart';
-
-/// The asset manager for an individual package.
-///
-/// This keeps track of which transformers are applied to which assets, and
-/// re-runs those transformers when their dependencies change. The transformed
-/// assets are accessible via [getAssetById].
-class AssetGraph {
-  /// The name of the package whose assets are managed.
-  final String package;
-
-  /// The [AssetGraphManager] that manages the [AssetGraph]s for all
-  /// dependencies of the current app.
-  final AssetGraphManager _manager;
-
-  final _phases = <Phase>[];
-
-  /// A stream that emits a [BuildResult] each time the build is completed,
-  /// whether or not it succeeded.
-  ///
-  /// If an unexpected error in barback itself occurs, it will be emitted
-  /// through this stream's error channel.
-  Stream<BuildResult> get results => _resultsController.stream;
-  final _resultsController = new StreamController<BuildResult>.broadcast();
-
-  /// A stream that emits any errors from the asset graph or the transformers.
-  ///
-  /// This emits errors as they're detected. If an error occurs in one part of
-  /// the asset graph, unrelated parts will continue building.
-  ///
-  /// This will not emit programming errors from barback itself. Those will be
-  /// emitted through the [results] stream's error channel.
-  Stream get errors => _errorsController.stream;
-  final _errorsController = new StreamController.broadcast();
-
-  /// The errors that have occurred since the current build started.
-  ///
-  /// This will be empty if no build is occurring.
-  Queue _accumulatedErrors;
-
-  /// A future that completes when the currently running build process finishes.
-  ///
-  /// If no build it in progress, is `null`.
-  Future _processDone;
-
-  ChangeBatch _sourceChanges;
-
-  /// Creates a new [AssetGraph].
-  ///
-  /// It loads source assets within [package] using [provider] and then uses
-  /// [transformerPhases] to generate output files from them.
-  //TODO(rnystrom): Better way of specifying transformers and their ordering.
-  AssetGraph(this._manager, this.package,
-      Iterable<Iterable<Transformer>> transformerPhases) {
-    // Flatten the phases to a list so we can traverse backwards to wire up
-    // each phase to its next.
-    var phases = transformerPhases.toList();
-
-    // Each phase writes its outputs as inputs to the next phase after it.
-    // Add a phase at the end for the final outputs of the last phase.
-    phases.add([]);
-
-    Phase nextPhase = null;
-    for (var transformers in phases.reversed) {
-      nextPhase = new Phase(this, _phases.length, transformers.toList(),
-          nextPhase);
-      _phases.insert(0, nextPhase);
-    }
-  }
-
-  /// Gets the asset identified by [id].
-  ///
-  /// If [id] is for a generated or transformed asset, this will wait until
-  /// it has been created and return it. If the asset cannot be found, throws
-  /// [AssetNotFoundException].
-  Future<Asset> getAssetById(AssetId id) {
-    assert(id.package == package);
-
-    // TODO(rnystrom): Waiting for the entire build to complete is unnecessary
-    // in some cases. Should optimize:
-    // * [id] may be generated before the compilation is finished. We should
-    //   be able to quickly check whether there are any more in-place
-    //   transformations that can be run on it. If not, we can return it early.
-    // * If everything is compiled, something that didn't output [id] is
-    //   dirtied, and then [id] is requested, we can return it immediately,
-    //   since anything overwriting it at that point is an error.
-    // * If [id] has never been generated and all active transformers provide
-    //   metadata about the file names of assets it can emit, we can prove that
-    //   none of them can emit [id] and fail early.
-    return (_processDone == null ? new Future.value() : _processDone).then((_) {
-      // Each phase's inputs are the outputs of the previous phase. Find the
-      // last phase that contains the asset. Since the last phase has no
-      // transformers, this will find the latest output for that id.
-
-      // TODO(rnystrom): Currently does not omit assets that are actually used
-      // as inputs for transformers. This means you can request and get an
-      // asset that should be "consumed" because it's used to generate the
-      // real asset you care about. Need to figure out how we want to handle
-      // that and what use cases there are related to it.
-      for (var i = _phases.length - 1; i >= 0; i--) {
-        var node = _phases[i].inputs[id];
-        if (node != null) {
-          // By the time we get here, the asset should have been built.
-          assert(node.asset != null);
-          return node.asset;
-        }
-      }
-
-      // Couldn't find it.
-      throw new AssetNotFoundException(id);
-    });
-  }
-
-  /// Adds [sources] to the graph's known set of source assets.
-  ///
-  /// Begins applying any transforms that can consume any of the sources. If a
-  /// given source is already known, it is considered modified and all
-  /// transforms that use it will be re-applied.
-  void updateSources(Iterable<AssetId> sources) {
-    if (_sourceChanges == null) _sourceChanges = new ChangeBatch();
-    assert(sources.every((id) => id.package == package));
-    _sourceChanges.update(sources);
-
-    _waitForProcess();
-  }
-
-  /// Removes [removed] from the graph's known set of source assets.
-  void removeSources(Iterable<AssetId> removed) {
-    if (_sourceChanges == null) _sourceChanges = new ChangeBatch();
-    assert(removed.every((id) => id.package == package));
-    _sourceChanges.remove(removed);
-
-    _waitForProcess();
-  }
-
-  void reportError(error) {
-    _accumulatedErrors.add(error);
-    _errorsController.add(error);
-  }
-
-  /// Starts the build process asynchronously if there is work to be done.
-  ///
-  /// Returns a future that completes with the background processing is done.
-  /// If there is no work to do, returns a future that completes immediately.
-  /// All errors that occur during processing will be caught (and routed to the
-  /// [results] stream) before they get to the returned future, so it is safe
-  /// to discard it.
-  Future _waitForProcess() {
-    if (_processDone != null) return _processDone;
-
-    _accumulatedErrors = new Queue();
-    return _processDone = _process().then((_) {
-      // Report the build completion.
-      // TODO(rnystrom): Put some useful data in here.
-      _resultsController.add(new BuildResult(_accumulatedErrors));
-    }).catchError((error) {
-      // If we get here, it's an unexpected error. Runtime errors like missing
-      // assets should be handled earlier. Errors from transformers or other
-      // external code that barback calls into should be caught at that API
-      // boundary.
-      //
-      // On the off chance we get here, pipe the error to the results stream
-      // as an error. That will let applications handle it without it appearing
-      // in the same path as "normal" errors that get reported.
-      _resultsController.addError(error);
-    }).whenComplete(() {
-      _processDone = null;
-      _accumulatedErrors = null;
-    });
-  }
-
-  /// Starts the background processing.
-  ///
-  /// Returns a future that completes when all assets have been processed.
-  Future _process() {
-    return _processSourceChanges().then((_) {
-      // Find the first phase that has work to do and do it.
-      var future;
-      for (var phase in _phases) {
-        future = phase.process();
-        if (future != null) break;
-      }
-
-      // If all phases are done and no new updates have come in, we're done.
-      if (future == null) {
-        // If changes have come in, start over.
-        if (_sourceChanges != null) return _process();
-
-        // Otherwise, everything is done.
-        return;
-      }
-
-      // Process that phase and then loop onto the next.
-      return future.then((_) => _process());
-    });
-  }
-
-  /// Processes the current batch of changes to source assets.
-  Future _processSourceChanges() {
-    // Always pump the event loop. This ensures a bunch of synchronous source
-    // changes are processed in a single batch even when the first one starts
-    // the build process.
-    return new Future(() {
-      if (_sourceChanges == null) return null;
-
-      // Take the current batch to ensure it doesn't get added to while we're
-      // processing it.
-      var changes = _sourceChanges;
-      _sourceChanges = null;
-
-      var updated = new AssetSet();
-      var futures = [];
-      for (var id in changes.updated) {
-        // TODO(rnystrom): Catch all errors from provider and route to results.
-        futures.add(_manager.provider.getAsset(id).then((asset) {
-          updated.add(asset);
-        }).catchError((error) {
-          if (error is AssetNotFoundException) {
-            // Handle missing asset errors like regular missing assets.
-            reportError(error);
-          } else {
-            // It's an unexpected error, so rethrow it.
-            throw error;
-          }
-        }));
-      }
-
-      return Future.wait(futures).then((_) {
-        _phases.first.updateInputs(updated, changes.removed);
-      });
-    });
-  }
-}
-
-/// An event indicating that the asset graph has finished building.
-///
-/// A build can end either in success or failure. If there were no errors during
-/// the build, it's considered to be a success; any errors render it a failure,
-/// although individual assets may still have built successfully.
-class BuildResult {
-  /// All errors that occurred during the build.
-  final List errors;
-
-  /// `true` if the build succeeded.
-  bool get succeeded => errors.isEmpty;
-
-  BuildResult(Iterable errors)
-      : errors = errors.toList();
-
-  /// Creates a build result indicating a successful build.
-  ///
-  /// This equivalent to a build result with no errors.
-  BuildResult.success()
-      : this([]);
-
-  String toString() {
-    if (succeeded) return "success";
-
-    return "errors:\n" + errors.map((error) {
-      var stackTrace = getAttachedStackTrace(error);
-      if (stackTrace != null) stackTrace = new Trace.from(stackTrace);
-
-      var msg = new StringBuffer();
-      msg.write(prefixLines(error.toString()));
-      if (stackTrace != null) {
-        msg.write("\n\n");
-        msg.write("Stack trace:\n");
-        msg.write(prefixLines(stackTrace.toString()));
-      }
-      return msg.toString();
-    }).join("\n\n");
-  }
-}