Use allowed_experiments.json when building SDK summary (reland).

Landed: https://dart-review.googlesource.com/c/sdk/+/149052 Reverted: https://dart-review.googlesource.com/c/sdk/+/149201 Change-Id: Ief9430c58254fe8cbdcedc8d3678c61d4c086f67 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149364 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
2020-05-29 16:31:35 +00:00
parent 609c0d35eb
commit 6a551f8d54
14 changed files with 340 additions and 135 deletions
@@ -7,27 +7,23 @@ import 'dart:async';
 import 'package:analysis_server/src/context_manager.dart';
 import 'package:analysis_server/src/plugin/notification_manager.dart';
 import 'package:analysis_server/src/utilities/null_string_sink.dart';
-import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/source/error_processor.dart';
 import 'package:analyzer/src/context/builder.dart';
-import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/context/context_root.dart';
 import 'package:analyzer/src/dart/analysis/byte_store.dart';
 import 'package:analyzer/src/dart/analysis/driver.dart';
 import 'package:analyzer/src/dart/analysis/file_state.dart';
 import 'package:analyzer/src/dart/analysis/performance_logger.dart';
-import 'package:analyzer/src/dart/analysis/session.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:analyzer/src/services/lint.dart';
-import 'package:analyzer/src/summary/summary_file_builder.dart';
 import 'package:analyzer/src/test_utilities/mock_sdk.dart';
 import 'package:analyzer/src/test_utilities/resource_provider_mixin.dart';
 import 'package:analyzer/src/util/glob.dart';
@@ -1811,11 +1807,6 @@ include: package:boo/other_options.yaml
    var sdkExtPath = '$projPath/sdk_ext';
    newFile('$projPath/test', content: 'test.dart');
    newFile('$sdkExtPath/entry.dart');
-    var synchronousSession = SynchronousSession(analysisOptions, null);
-    var bytes =
-        SummaryBuilder([], AnalysisContextImpl(synchronousSession, null))
-            .build(featureSet: FeatureSet.fromEnableFlags([]));
-    newFileWithBytes('$projPath/sdk.ds', bytes);
    // Setup _embedder.yaml.
    newFile('$libPath/_embedder.yaml', content: r'''
 embedded_libs:
@@ -39,6 +39,11 @@ class EmbedderSdk extends AbstractDartSdk {
  }

  // TODO(danrubel) Determine SDK version
+  @override
+  String get allowedExperimentsJson {
+    return null;
+  }
+
  @override
  String get sdkVersion => '0';

@@ -4,13 +4,10 @@

 import 'package:_fe_analyzer_shared/src/sdk/allowed_experiments.dart';
 import 'package:analyzer/dart/analysis/features.dart';
-import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/context/packages.dart';
 import 'package:analyzer/src/dart/analysis/experiments.dart';
-import 'package:analyzer/src/dart/sdk/sdk.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
-import 'package:analyzer/src/test_utilities/mock_sdk.dart';
 import 'package:meta/meta.dart';
 import 'package:pub_semver/pub_semver.dart';

@@ -97,20 +94,9 @@ class FeatureSetProvider {
  }

  static AllowedExperiments _experimentsForSdk(DartSdk sdk) {
-    Folder sdkFolder;
-    if (sdk is FolderBasedDartSdk) {
-      sdkFolder = sdk.directory;
-    } else if (sdk is MockSdk) {
-      sdkFolder = sdk.directory;
-    }
-
-    if (sdkFolder != null) {
+    var experimentsContent = sdk.allowedExperimentsJson;
+    if (experimentsContent != null) {
      try {
-        var experimentsContent = sdkFolder
-            .getChildAssumingFolder('lib')
-            .getChildAssumingFolder('_internal')
-            .getChildAssumingFile('allowed_experiments.json')
-            .readAsStringSync();
        return parseAllowedExperiments(experimentsContent);
      } catch (_) {}
    }
@@ -277,6 +277,11 @@ class EmbedderSdk extends AbstractDartSdk {
    }
  }

+  @override
+  String get allowedExperimentsJson {
+    return null;
+  }
+
  @override
  // TODO(danrubel) Determine SDK version
  String get sdkVersion => '0';
@@ -464,6 +469,19 @@ class FolderBasedDartSdk extends AbstractDartSdk {
    libraryMap = initialLibraryMap();
  }

+  @override
+  String get allowedExperimentsJson {
+    try {
+      return _sdkDirectory
+          .getChildAssumingFolder('lib')
+          .getChildAssumingFolder('_internal')
+          .getChildAssumingFile('allowed_experiments.json')
+          .readAsStringSync();
+    } catch (_) {
+      return null;
+    }
+  }
+
  /**
   * Return the directory containing the SDK.
   */
@@ -42,6 +42,10 @@ abstract class DartSdk {
   */
  static const String DEFAULT_VERSION = "0";

+  /// Return the content of the `allowed_experiments.json` file, or `null`
+  /// if the file cannot be read, e.g. does not exist.
+  String get allowedExperimentsJson;
+
  /**
   * Return the analysis context used for all of the sources in this [DartSdk].
   */
@@ -17444,6 +17444,7 @@ class PackageBundleBuilder extends Object
    with _PackageBundleMixin
    implements idl.PackageBundle {
  LinkedNodeBundleBuilder _bundle2;
+  PackageBundleSdkBuilder _sdk;

  @override
  LinkedNodeBundleBuilder get bundle2 => _bundle2;
@@ -17453,17 +17454,31 @@ class PackageBundleBuilder extends Object
    this._bundle2 = value;
  }

-  PackageBundleBuilder({LinkedNodeBundleBuilder bundle2}) : _bundle2 = bundle2;
+  @override
+  PackageBundleSdkBuilder get sdk => _sdk;
+
+  /// The SDK specific data, if this bundle is for SDK.
+  set sdk(PackageBundleSdkBuilder value) {
+    this._sdk = value;
+  }
+
+  PackageBundleBuilder(
+      {LinkedNodeBundleBuilder bundle2, PackageBundleSdkBuilder sdk})
+      : _bundle2 = bundle2,
+        _sdk = sdk;

  /// Flush [informative] data recursively.
  void flushInformative() {
    _bundle2?.flushInformative();
+    _sdk?.flushInformative();
  }

  /// Accumulate non-[informative] data into [signature].
  void collectApiSignature(api_sig.ApiSignature signature) {
    signature.addBool(this._bundle2 != null);
    this._bundle2?.collectApiSignature(signature);
+    signature.addBool(this._sdk != null);
+    this._sdk?.collectApiSignature(signature);
  }

  List<int> toBuffer() {
@@ -17473,13 +17488,20 @@ class PackageBundleBuilder extends Object

  fb.Offset finish(fb.Builder fbBuilder) {
    fb.Offset offset_bundle2;
+    fb.Offset offset_sdk;
    if (_bundle2 != null) {
      offset_bundle2 = _bundle2.finish(fbBuilder);
    }
+    if (_sdk != null) {
+      offset_sdk = _sdk.finish(fbBuilder);
+    }
    fbBuilder.startTable();
    if (offset_bundle2 != null) {
      fbBuilder.addOffset(0, offset_bundle2);
    }
+    if (offset_sdk != null) {
+      fbBuilder.addOffset(1, offset_sdk);
+    }
    return fbBuilder.endTable();
  }
 }
@@ -17506,6 +17528,7 @@ class _PackageBundleImpl extends Object
  _PackageBundleImpl(this._bc, this._bcOffset);

  idl.LinkedNodeBundle _bundle2;
+  idl.PackageBundleSdk _sdk;

  @override
  idl.LinkedNodeBundle get bundle2 {
@@ -17513,6 +17536,12 @@ class _PackageBundleImpl extends Object
        const _LinkedNodeBundleReader().vTableGet(_bc, _bcOffset, 0, null);
    return _bundle2;
  }
+
+  @override
+  idl.PackageBundleSdk get sdk {
+    _sdk ??= const _PackageBundleSdkReader().vTableGet(_bc, _bcOffset, 1, null);
+    return _sdk;
+  }
 }

 abstract class _PackageBundleMixin implements idl.PackageBundle {
@@ -17522,12 +17551,99 @@ abstract class _PackageBundleMixin implements idl.PackageBundle {
    if (bundle2 != null) {
      _result["bundle2"] = bundle2.toJson();
    }
+    if (sdk != null) {
+      _result["sdk"] = sdk.toJson();
+    }
    return _result;
  }

  @override
  Map<String, Object> toMap() => {
        "bundle2": bundle2,
+        "sdk": sdk,
+      };
+
+  @override
+  String toString() => convert.json.encode(toJson());
+}
+
+class PackageBundleSdkBuilder extends Object
+    with _PackageBundleSdkMixin
+    implements idl.PackageBundleSdk {
+  String _allowedExperimentsJson;
+
+  @override
+  String get allowedExperimentsJson => _allowedExperimentsJson ??= '';
+
+  /// The content of the `allowed_experiments.json` from SDK.
+  set allowedExperimentsJson(String value) {
+    this._allowedExperimentsJson = value;
+  }
+
+  PackageBundleSdkBuilder({String allowedExperimentsJson})
+      : _allowedExperimentsJson = allowedExperimentsJson;
+
+  /// Flush [informative] data recursively.
+  void flushInformative() {}
+
+  /// Accumulate non-[informative] data into [signature].
+  void collectApiSignature(api_sig.ApiSignature signature) {
+    signature.addString(this._allowedExperimentsJson ?? '');
+  }
+
+  fb.Offset finish(fb.Builder fbBuilder) {
+    fb.Offset offset_allowedExperimentsJson;
+    if (_allowedExperimentsJson != null) {
+      offset_allowedExperimentsJson =
+          fbBuilder.writeString(_allowedExperimentsJson);
+    }
+    fbBuilder.startTable();
+    if (offset_allowedExperimentsJson != null) {
+      fbBuilder.addOffset(0, offset_allowedExperimentsJson);
+    }
+    return fbBuilder.endTable();
+  }
+}
+
+class _PackageBundleSdkReader extends fb.TableReader<_PackageBundleSdkImpl> {
+  const _PackageBundleSdkReader();
+
+  @override
+  _PackageBundleSdkImpl createObject(fb.BufferContext bc, int offset) =>
+      _PackageBundleSdkImpl(bc, offset);
+}
+
+class _PackageBundleSdkImpl extends Object
+    with _PackageBundleSdkMixin
+    implements idl.PackageBundleSdk {
+  final fb.BufferContext _bc;
+  final int _bcOffset;
+
+  _PackageBundleSdkImpl(this._bc, this._bcOffset);
+
+  String _allowedExperimentsJson;
+
+  @override
+  String get allowedExperimentsJson {
+    _allowedExperimentsJson ??=
+        const fb.StringReader().vTableGet(_bc, _bcOffset, 0, '');
+    return _allowedExperimentsJson;
+  }
+}
+
+abstract class _PackageBundleSdkMixin implements idl.PackageBundleSdk {
+  @override
+  Map<String, Object> toJson() {
+    Map<String, Object> _result = <String, Object>{};
+    if (allowedExperimentsJson != '') {
+      _result["allowedExperimentsJson"] = allowedExperimentsJson;
+    }
+    return _result;
+  }
+
+  @override
+  Map<String, Object> toMap() => {
+        "allowedExperimentsJson": allowedExperimentsJson,
      };

  @override
@@ -19565,10 +19681,10 @@ class UnlinkedUnit2Builder extends Object
  List<UnlinkedNamespaceDirectiveBuilder> _exports;
  bool _hasLibraryDirective;
  bool _hasPartOfDirective;
-  String _partOfUri;
  List<UnlinkedNamespaceDirectiveBuilder> _imports;
  List<UnlinkedInformativeDataBuilder> _informativeData;
  List<int> _lineStarts;
+  String _partOfUri;
  List<String> _parts;

  @override
@@ -19606,14 +19722,6 @@ class UnlinkedUnit2Builder extends Object
    this._hasPartOfDirective = value;
  }

-  @override
-  String get partOfUri => _partOfUri ??= '';
-
-  /// URI of the `part of` directive.
-  set partOfUri(String value) {
-    this._partOfUri = value;
-  }
-
  @override
  List<UnlinkedNamespaceDirectiveBuilder> get imports =>
      _imports ??= <UnlinkedNamespaceDirectiveBuilder>[];
@@ -19640,6 +19748,14 @@ class UnlinkedUnit2Builder extends Object
    this._lineStarts = value;
  }

+  @override
+  String get partOfUri => _partOfUri ??= '';
+
+  /// URI of the `part of` directive.
+  set partOfUri(String value) {
+    this._partOfUri = value;
+  }
+
  @override
  List<String> get parts => _parts ??= <String>[];

@@ -19653,19 +19769,19 @@ class UnlinkedUnit2Builder extends Object
      List<UnlinkedNamespaceDirectiveBuilder> exports,
      bool hasLibraryDirective,
      bool hasPartOfDirective,
-      String partOfUri,
      List<UnlinkedNamespaceDirectiveBuilder> imports,
      List<UnlinkedInformativeDataBuilder> informativeData,
      List<int> lineStarts,
+      String partOfUri,
      List<String> parts})
      : _apiSignature = apiSignature,
        _exports = exports,
        _hasLibraryDirective = hasLibraryDirective,
        _hasPartOfDirective = hasPartOfDirective,
-        _partOfUri = partOfUri,
        _imports = imports,
        _informativeData = informativeData,
        _lineStarts = lineStarts,
+        _partOfUri = partOfUri,
        _parts = parts;

  /// Flush [informative] data recursively.
@@ -19731,10 +19847,10 @@ class UnlinkedUnit2Builder extends Object
  fb.Offset finish(fb.Builder fbBuilder) {
    fb.Offset offset_apiSignature;
    fb.Offset offset_exports;
-    fb.Offset offset_partOfUri;
    fb.Offset offset_imports;
    fb.Offset offset_informativeData;
    fb.Offset offset_lineStarts;
+    fb.Offset offset_partOfUri;
    fb.Offset offset_parts;
    if (!(_apiSignature == null || _apiSignature.isEmpty)) {
      offset_apiSignature = fbBuilder.writeListUint32(_apiSignature);
@@ -19743,9 +19859,6 @@ class UnlinkedUnit2Builder extends Object
      offset_exports = fbBuilder
          .writeList(_exports.map((b) => b.finish(fbBuilder)).toList());
    }
-    if (_partOfUri != null) {
-      offset_partOfUri = fbBuilder.writeString(_partOfUri);
-    }
    if (!(_imports == null || _imports.isEmpty)) {
      offset_imports = fbBuilder
          .writeList(_imports.map((b) => b.finish(fbBuilder)).toList());
@@ -19757,6 +19870,9 @@ class UnlinkedUnit2Builder extends Object
    if (!(_lineStarts == null || _lineStarts.isEmpty)) {
      offset_lineStarts = fbBuilder.writeListUint32(_lineStarts);
    }
+    if (_partOfUri != null) {
+      offset_partOfUri = fbBuilder.writeString(_partOfUri);
+    }
    if (!(_parts == null || _parts.isEmpty)) {
      offset_parts = fbBuilder
          .writeList(_parts.map((b) => fbBuilder.writeString(b)).toList());
@@ -19774,9 +19890,6 @@ class UnlinkedUnit2Builder extends Object
    if (_hasPartOfDirective == true) {
      fbBuilder.addBool(3, true);
    }
-    if (offset_partOfUri != null) {
-      fbBuilder.addOffset(8, offset_partOfUri);
-    }
    if (offset_imports != null) {
      fbBuilder.addOffset(2, offset_imports);
    }
@@ -19786,6 +19899,9 @@ class UnlinkedUnit2Builder extends Object
    if (offset_lineStarts != null) {
      fbBuilder.addOffset(5, offset_lineStarts);
    }
+    if (offset_partOfUri != null) {
+      fbBuilder.addOffset(8, offset_partOfUri);
+    }
    if (offset_parts != null) {
      fbBuilder.addOffset(4, offset_parts);
    }
@@ -19818,10 +19934,10 @@ class _UnlinkedUnit2Impl extends Object
  List<idl.UnlinkedNamespaceDirective> _exports;
  bool _hasLibraryDirective;
  bool _hasPartOfDirective;
-  String _partOfUri;
  List<idl.UnlinkedNamespaceDirective> _imports;
  List<idl.UnlinkedInformativeData> _informativeData;
  List<int> _lineStarts;
+  String _partOfUri;
  List<String> _parts;

  @override
@@ -19853,12 +19969,6 @@ class _UnlinkedUnit2Impl extends Object
    return _hasPartOfDirective;
  }

-  @override
-  String get partOfUri {
-    _partOfUri ??= const fb.StringReader().vTableGet(_bc, _bcOffset, 8, '');
-    return _partOfUri;
-  }
-
  @override
  List<idl.UnlinkedNamespaceDirective> get imports {
    _imports ??= const fb.ListReader<idl.UnlinkedNamespaceDirective>(
@@ -19882,6 +19992,12 @@ class _UnlinkedUnit2Impl extends Object
    return _lineStarts;
  }

+  @override
+  String get partOfUri {
+    _partOfUri ??= const fb.StringReader().vTableGet(_bc, _bcOffset, 8, '');
+    return _partOfUri;
+  }
+
  @override
  List<String> get parts {
    _parts ??= const fb.ListReader<String>(fb.StringReader())
@@ -19906,9 +20022,6 @@ abstract class _UnlinkedUnit2Mixin implements idl.UnlinkedUnit2 {
    if (hasPartOfDirective != false) {
      _result["hasPartOfDirective"] = hasPartOfDirective;
    }
-    if (partOfUri != '') {
-      _result["partOfUri"] = partOfUri;
-    }
    if (imports.isNotEmpty) {
      _result["imports"] = imports.map((_value) => _value.toJson()).toList();
    }
@@ -19919,6 +20032,9 @@ abstract class _UnlinkedUnit2Mixin implements idl.UnlinkedUnit2 {
    if (lineStarts.isNotEmpty) {
      _result["lineStarts"] = lineStarts;
    }
+    if (partOfUri != '') {
+      _result["partOfUri"] = partOfUri;
+    }
    if (parts.isNotEmpty) {
      _result["parts"] = parts;
    }
@@ -19931,10 +20047,10 @@ abstract class _UnlinkedUnit2Mixin implements idl.UnlinkedUnit2 {
        "exports": exports,
        "hasLibraryDirective": hasLibraryDirective,
        "hasPartOfDirective": hasPartOfDirective,
-        "partOfUri": partOfUri,
        "imports": imports,
        "informativeData": informativeData,
        "lineStarts": lineStarts,
+        "partOfUri": partOfUri,
        "parts": parts,
      };

@@ -1253,6 +1253,15 @@ table LinkedNodeUnit {
 table PackageBundle {
  /// The version 2 of the summary.
  bundle2:LinkedNodeBundle (id: 0);
+
+  /// The SDK specific data, if this bundle is for SDK.
+  sdk:PackageBundleSdk (id: 1);
+}
+
+/// Summary information about a package.
+table PackageBundleSdk {
+  /// The content of the `allowed_experiments.json` from SDK.
+  allowedExperimentsJson:string (id: 0);
 }

 /// Summary information about a top-level type inference error.
@@ -1335,9 +1344,6 @@ table UnlinkedUnit2 {
  /// Is `true` if the unit contains a `part of` directive.
  hasPartOfDirective:bool (id: 3);

-  /// URI of the `part of` directive.
-  partOfUri:string (id: 8);
-
  /// URIs of `import` directives.
  imports:[UnlinkedNamespaceDirective] (id: 2);

@@ -1346,6 +1352,9 @@ table UnlinkedUnit2 {
  /// Offsets of the first character of each line in the source code.
  lineStarts:[uint] (id: 5);

+  /// URI of the `part of` directive.
+  partOfUri:string (id: 8);
+
  /// URIs of `part` directives.
  parts:[string] (id: 4);
 }
@@ -1888,6 +1888,17 @@ abstract class PackageBundle extends base.SummaryClass {
  /// The version 2 of the summary.
  @Id(0)
  LinkedNodeBundle get bundle2;
+
+  /// The SDK specific data, if this bundle is for SDK.
+  @Id(1)
+  PackageBundleSdk get sdk;
+}
+
+/// Summary information about a package.
+abstract class PackageBundleSdk extends base.SummaryClass {
+  /// The content of the `allowed_experiments.json` from SDK.
+  @Id(0)
+  String get allowedExperimentsJson;
 }

 /// Summary information about a top-level type inference error.
@@ -2244,10 +2255,6 @@ abstract class UnlinkedUnit2 extends base.SummaryClass {
  @Id(3)
  bool get hasPartOfDirective;

-  /// URI of the `part of` directive.
-  @Id(8)
-  String get partOfUri;
-
  /// URIs of `import` directives.
  @Id(2)
  List<UnlinkedNamespaceDirective> get imports;
@@ -2260,6 +2267,10 @@ abstract class UnlinkedUnit2 extends base.SummaryClass {
  @Id(5)
  List<int> get lineStarts;

+  /// URI of the `part of` directive.
+  @Id(8)
+  String get partOfUri;
+
  /// URIs of `part` directives.
  @Id(4)
  List<String> get parts;
@@ -4,6 +4,7 @@

 import 'dart:collection';

+import 'package:_fe_analyzer_shared/src/sdk/allowed_experiments.dart';
 import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/dart/analysis/utilities.dart';
 import 'package:analyzer/dart/ast/ast.dart';
@@ -14,70 +15,104 @@ import 'package:analyzer/src/dart/sdk/sdk.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/src/summary/format.dart';
 import 'package:analyzer/src/summary/summarize_elements.dart';
 import 'package:analyzer/src/summary2/link.dart' as summary2;
 import 'package:analyzer/src/summary2/linked_element_factory.dart' as summary2;
 import 'package:analyzer/src/summary2/reference.dart' as summary2;
 import 'package:meta/meta.dart';

-class SummaryBuilder {
-  final Iterable<Source> librarySources;
-  final AnalysisContext context;
+List<int> buildSdkSummary({
+  @required ResourceProvider resourceProvider,
+  @required String sdkPath,
+}) {
+  //
+  // Prepare SDK.
+  //
+  FolderBasedDartSdk sdk =
+      FolderBasedDartSdk(resourceProvider, resourceProvider.getFolder(sdkPath));
+  sdk.useSummary = false;
+  sdk.analysisOptions = AnalysisOptionsImpl();

-  /**
-   * Create a summary builder for these [librarySources] and [context].
-   */
-  SummaryBuilder(this.librarySources, this.context);
+  //
+  // Prepare 'dart:' URIs to serialize.
+  //
+  Set<String> uriSet =
+      sdk.sdkLibraries.map((SdkLibrary library) => library.shortName).toSet();
+  // TODO(scheglov) Why do we need it?
+  uriSet.add('dart:html_common/html_common_dart2js.dart');

-  /**
-   * Create an SDK summary builder for the dart SDK at the given [sdkPath].
-   */
-  factory SummaryBuilder.forSdk(String sdkPath) {
-    //
-    // Prepare SDK.
-    //
-    ResourceProvider resourceProvider = PhysicalResourceProvider.INSTANCE;
-    FolderBasedDartSdk sdk = FolderBasedDartSdk(
-        resourceProvider, resourceProvider.getFolder(sdkPath));
-    sdk.useSummary = false;
-    sdk.analysisOptions = AnalysisOptionsImpl();
-
-    //
-    // Prepare 'dart:' URIs to serialize.
-    //
-    Set<String> uriSet =
-        sdk.sdkLibraries.map((SdkLibrary library) => library.shortName).toSet();
-    uriSet.add('dart:html_common/html_common_dart2js.dart');
-
-    Set<Source> librarySources = HashSet<Source>();
-    for (String uri in uriSet) {
-      librarySources.add(sdk.mapDartUri(uri));
+  Set<Source> librarySources = HashSet<Source>();
+  for (String uri in uriSet) {
+    var source = sdk.mapDartUri(uri);
+    // TODO(scheglov) Fix the previous TODO and remove this check.
+    if (source != null) {
+      librarySources.add(source);
    }
-
-    return SummaryBuilder(librarySources, sdk.context);
  }

+  String allowedExperimentsJson;
+  try {
+    allowedExperimentsJson = sdk.directory
+        .getChildAssumingFolder('lib')
+        .getChildAssumingFolder('_internal')
+        .getChildAssumingFile('allowed_experiments.json')
+        .readAsStringSync();
+  } catch (_) {}
+
+  return _Builder(
+    sdk.context,
+    allowedExperimentsJson,
+    librarySources,
+  ).build();
+}
+
+@Deprecated('Use buildSdkSummary()')
+class SummaryBuilder {
+  final ResourceProvider resourceProvider;
+  final String sdkPath;
+
+  factory SummaryBuilder.forSdk(String sdkPath) {
+    return SummaryBuilder.forSdk2(
+      resourceProvider: PhysicalResourceProvider.INSTANCE,
+      sdkPath: sdkPath,
+    );
+  }
+
+  SummaryBuilder.forSdk2({
+    @required this.resourceProvider,
+    @required this.sdkPath,
+  });
+
  /**
   * Build the linked bundle and return its bytes.
   */
-  List<int> build({
-    @required FeatureSet featureSet,
-  }) {
-    return _Builder(context, featureSet, librarySources).build();
+  List<int> build() {
+    return buildSdkSummary(
+      resourceProvider: resourceProvider,
+      sdkPath: sdkPath,
+    );
  }
 }

 class _Builder {
  final AnalysisContext context;
-  final FeatureSet featureSet;
+  final String allowedExperimentsJson;
  final Iterable<Source> librarySources;

  final Set<String> libraryUris = <String>{};
  final List<summary2.LinkInputLibrary> inputLibraries = [];

+  AllowedExperiments allowedExperiments;
  final PackageBundleAssembler bundleAssembler = PackageBundleAssembler();

-  _Builder(this.context, this.featureSet, this.librarySources);
+  _Builder(
+    this.context,
+    this.allowedExperimentsJson,
+    this.librarySources,
+  ) {
+    allowedExperiments = _parseAllowedExperiments(allowedExperimentsJson);
+  }

  /**
   * Build the linked bundle and return its bytes.
@@ -94,7 +129,12 @@ class _Builder {
    var linkResult = summary2.link(elementFactory, inputLibraries);
    bundleAssembler.setBundle2(linkResult.bundle);

-    return bundleAssembler.assemble().toBuffer();
+    return PackageBundleBuilder(
+      bundle2: linkResult.bundle,
+      sdk: PackageBundleSdkBuilder(
+        allowedExperimentsJson: allowedExperimentsJson,
+      ),
+    ).toBuffer();
  }

  void _addLibrary(Source source) {
@@ -130,10 +170,23 @@ class _Builder {
    );
  }

+  /// Return the [FeatureSet] for the given [uri], must be a `dart:` URI.
+  FeatureSet _featureSet(Uri uri) {
+    if (uri.isScheme('dart')) {
+      var pathSegments = uri.pathSegments;
+      if (pathSegments.isNotEmpty) {
+        var libraryName = pathSegments.first;
+        var experiments = allowedExperiments.forSdkLibrary(libraryName);
+        return FeatureSet.fromEnableFlags(experiments);
+      }
+    }
+    throw StateError('Expected a valid dart: URI: $uri');
+  }
+
  CompilationUnit _parse(Source source) {
    var result = parseString(
      content: source.contents.data,
-      featureSet: featureSet,
+      featureSet: _featureSet(source.uri),
      throwIfDiagnostics: false,
    );

@@ -149,4 +202,16 @@ class _Builder {

    return result.unit;
  }
+
+  static AllowedExperiments _parseAllowedExperiments(String content) {
+    if (content == null) {
+      return AllowedExperiments(
+        sdkDefaultExperiments: [],
+        sdkLibraryExperiments: {},
+        packageExperiments: {},
+      );
+    }
+
+    return parseAllowedExperiments(content);
+  }
 }
@@ -43,6 +43,11 @@ class SummaryBasedDartSdk implements DartSdk {
    _bundle = bundle;
  }

+  @override
+  String get allowedExperimentsJson {
+    return _bundle.sdk?.allowedExperimentsJson;
+  }
+
  /**
   * Return the [PackageBundle] for this SDK, not `null`.
   */
@@ -2,7 +2,6 @@
 // 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 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/context/context.dart';
@@ -1067,7 +1066,7 @@ final Map<String, String> _librariesDartEntries = {
  'ffi': 'const LibraryInfo("ffi/ffi.dart")',
  'html': 'const LibraryInfo("html/dart2js/html_dart2js.dart")',
  'io': 'const LibraryInfo("io/io.dart")',
-  'isolate': 'const LibraryInfo("io/isolate.dart")',
+  'isolate': 'const LibraryInfo("isolate/isolate.dart")',
  'math': 'const LibraryInfo("math/math.dart")',
 };

@@ -1158,6 +1157,21 @@ class MockSdk implements DartSdk {
    );
  }

+  @override
+  String get allowedExperimentsJson {
+    try {
+      var convertedRoot = resourceProvider.convertPath(sdkRoot);
+      return resourceProvider
+          .getFolder(convertedRoot)
+          .getChildAssumingFolder('lib')
+          .getChildAssumingFolder('_internal')
+          .getChildAssumingFile('allowed_experiments.json')
+          .readAsStringSync();
+    } catch (_) {
+      return null;
+    }
+  }
+
  @override
  AnalysisContextImpl get context {
    if (_analysisContext == null) {
@@ -1167,11 +1181,6 @@ class MockSdk implements DartSdk {
    return _analysisContext;
  }

-  Folder get directory {
-    var convertedRoot = resourceProvider.convertPath(sdkRoot);
-    return resourceProvider.getFolder(convertedRoot);
-  }
-
  @override
  String get sdkVersion => throw UnimplementedError();

@@ -1255,12 +1264,9 @@ class MockSdk implements DartSdk {

  /// Compute the bytes of the linked bundle associated with this SDK.
  List<int> _computeLinkedBundleBytes() {
-    List<Source> librarySources = sdkLibraries
-        .map((SdkLibrary library) => mapDartUri(library.shortName))
-        .toList();
-    var featureSet = FeatureSet.fromEnableFlags(['non-nullable']);
-    return SummaryBuilder(librarySources, context).build(
-      featureSet: featureSet,
+    return buildSdkSummary(
+      resourceProvider: resourceProvider,
+      sdkPath: sdkRoot,
    );
  }
 }
@@ -4,7 +4,6 @@

 import 'dart:io';

-import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/file_system/physical_file_system.dart';
 import 'package:analyzer/src/dart/sdk/sdk.dart';
 import 'package:analyzer/src/summary/summary_file_builder.dart';
@@ -42,18 +41,10 @@ void main(List<String> args) {
  //
  // Handle commands.
  //
-  if (command == 'build-non-nullable') {
+  if (command == 'build-strong') {
    _buildSummary(
      sdkPath,
      outFilePath,
-      enabledExperiments: ['non-nullable'],
-      title: 'non-nullable',
-    );
-  } else if (command == 'build-legacy' || command == 'build-strong') {
-    _buildSummary(
-      sdkPath,
-      outFilePath,
-      enabledExperiments: [],
      title: 'legacy',
    );
  } else {
@@ -70,14 +61,13 @@ const BINARY_NAME = "build_sdk_summaries";
 void _buildSummary(
  String sdkPath,
  String outPath, {
-  @required List<String> enabledExperiments,
  @required String title,
 }) {
  print('Generating $title summary.');
  Stopwatch sw = Stopwatch()..start();
-  var featureSet = FeatureSet.fromEnableFlags(enabledExperiments);
-  List<int> bytes = SummaryBuilder.forSdk(sdkPath).build(
-    featureSet: featureSet,
+  List<int> bytes = buildSdkSummary(
+    resourceProvider: PhysicalResourceProvider.INSTANCE,
+    sdkPath: sdkPath,
  );
  File(outPath).writeAsBytesSync(bytes, mode: FileMode.writeOnly);
  print('\tDone in ${sw.elapsedMilliseconds} ms.');
@@ -6,7 +6,6 @@ import 'dart:async';
 import 'dart:io' as io;
 import 'dart:isolate';

-import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/physical_file_system.dart';
@@ -159,9 +158,9 @@ class Driver with HasContextMixin implements CommandLineStarter {
      final stopwatch = Stopwatch()..start();

      for (var i = 0; i < 3; i++) {
-        var featureSet = FeatureSet.fromEnableFlags([]);
-        SummaryBuilder.forSdk(options.dartSdkPath).build(
-          featureSet: featureSet,
+        buildSdkSummary(
+          resourceProvider: PhysicalResourceProvider.INSTANCE,
+          sdkPath: options.dartSdkPath,
        );
      }

@@ -46,13 +46,13 @@ prebuilt_dart_action("generate_summary_strong") {
  outputs = [ output ]
  if (!dont_use_nnbd) {
    args = [
-      "build-non-nullable",
+      "build-strong",
      rebase_path(output),
      rebase_path("../../sdk_nnbd"),
    ]
  } else {
    args = [
-      "build-legacy",
+      "build-strong",
      rebase_path(output),
      rebase_path("../../sdk"),
    ]