Revert "Adding package:code_transformers for unifying common transformers code"

pkg/code_transformers/lib/src/test_harness.dart

-// Copyright (c) 2014, 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.
-
-/// Utilities for creating unit tests of Barback transformers.
-library code_transformers.src.test_harness;
-
-import 'dart:async';
-
-import 'package:barback/barback.dart';
-import 'package:stack_trace/stack_trace.dart';
-import 'package:unittest/unittest.dart';
-
-String idToString(AssetId id) => '${id.package}|${id.path}';
-AssetId idFromString(String s) {
-  int index = s.indexOf('|');
-  return new AssetId(s.substring(0, index), s.substring(index + 1));
-}
-
-String _removeTrailingWhitespace(String str) =>
-    str.splitMapJoin('\n',
-        onNonMatch: (s) => s.replaceAll(new RegExp(r'\s+$'), ''));
-
-/// A helper package provider that has files stored in memory, also wraps
-/// [Barback] to simply our tests.
-class TestHelper implements PackageProvider {
-
-  /// Maps from an asset string identifier of the form 'package|path' to the
-  /// file contents.
-  final Map<String, String> files;
-  final Iterable<String> packages;
-  final List<String> messages;
-  int messagesSeen = 0;
-  bool errorSeen = false;
-
-  Barback barback;
-  var errorSubscription;
-  var resultSubscription;
-  var logSubscription;
-
-  Future<Asset> getAsset(AssetId id) =>
-      new Future.value(new Asset.fromString(id, files[idToString(id)]));
-
-  TestHelper(List<List<Transformer>> transformers, Map<String, String> files,
-      this.messages)
-      : files = files,
-        packages = files.keys.map((s) => idFromString(s).package) {
-    barback = new Barback(this);
-    for (var p in packages) {
-      barback.updateTransformers(p, transformers);
-    }
-
-    errorSubscription = barback.errors.listen((e) {
-      var trace = null;
-      if (e is Error) trace = e.stackTrace;
-      if (trace != null) {
-        print(Trace.format(trace));
-      }
-      fail('error running barback: $e');
-    });
-
-    resultSubscription = barback.results.listen((result) {
-      expect(result.succeeded, !errorSeen, reason: "${result.errors}");
-    });
-
-    logSubscription = barback.log.listen((entry) {
-      // Ignore info messages.
-      if (entry.level == LogLevel.INFO) return;
-      if (entry.level == LogLevel.ERROR) errorSeen = true;
-      // We only check messages when an expectation is provided.
-      if (messages == null) return;
-
-      var msg = '${entry.level.name.toLowerCase()}: ${entry.message}';
-      var span = entry.span;
-      var spanInfo = span == null ? '' :
-          ' (${span.sourceUrl} ${span.start.line} ${span.start.column})';
-      expect(messagesSeen, lessThan(messages.length),
-          reason: 'more messages than expected.\nMessage seen: $msg$spanInfo');
-      expect('$msg$spanInfo', messages[messagesSeen++]);
-    });
-  }
-
-  void tearDown() {
-    errorSubscription.cancel();
-    resultSubscription.cancel();
-    logSubscription.cancel();
-  }
-
-  /// Tells barback which files have changed, and thus anything that depends on
-  /// it on should be computed. By default mark all the input files.
-  void run([Iterable<String> paths]) {
-    if (paths == null) paths = files.keys;
-    barback.updateSources(paths.map(idFromString));
-  }
-
-  Future<String> operator [](String assetString){
-    return barback.getAssetById(idFromString(assetString))
-        .then((asset) => asset.readAsString());
-  }
-
-  Future check(String assetIdString, String content) {
-    return this[assetIdString].then((value) {
-      value = _removeTrailingWhitespace(value);
-      content = _removeTrailingWhitespace(content);
-      expect(value, content, reason: 'Final output of $assetIdString differs.');
-    });
-  }
-
-  Future checkAll(Map<String, String> files) {
-    return barback.results.first.then((_) {
-      if (files == null) return null;
-      var futures = [];
-      files.forEach((k, v) {
-        futures.add(check(k, v));
-      });
-      return Future.wait(futures);
-    }).then((_) {
-      // We only check messages when an expectation is provided.
-      if (messages == null) return;
-      expect(messages.length, messagesSeen,
-          reason: 'less messages than expected');
-    });
-  }
-}