Revert "Switch FE to use the libraries.json format."

pkg/front_end/lib/src/base/libraries_specification.dart

Index: pkg/front_end/lib/src/base/libraries_specification.dart
diff --git a/pkg/front_end/lib/src/base/libraries_specification.dart b/pkg/front_end/lib/src/base/libraries_specification.dart
deleted file mode 100644
index f21c8a2579a0ea836570acc288a2df0f310dc0b5..0000000000000000000000000000000000000000
--- a/pkg/front_end/lib/src/base/libraries_specification.dart
+++ /dev/null
@@ -1,221 +0,0 @@
-// 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.
-
-/// Library specification in-memory representation.
-///
-/// Many dart tools are configurable to support different target platforms.  For
-/// a given target, they need to know what libraries are available and where are
-/// the sources and target-specific patches.
-///
-/// Here we define APIs to represent this specification and implement
-/// serialization to (and deserialization from) a JSON file.
-///
-/// Here is an example specification JSON file:
-///
-///     {
-///       "vm": {
-///         "libraries": {
-///             "core": {
-///                "uri": "async/core.dart",
-///                "patches": [
-///                    "path/to/core_patch.dart",
-///                    "path/to/list_patch.dart"
-///                ]
-///             }
-///             "async": {
-///                "uri": "async/async.dart",
-///                "patches": "path/to/async_patch.dart"
-///             }
-///             "convert": {
-///                "uri": "convert/convert.dart",
-///             }
-///         }
-///       }
-///     }
-///
-/// The format contains:
-///   - a top level entry for each target. Keys are target names (e.g. "vm"
-///     above), and values contain the entire specification of a target.
-///
-///   - each target specification is a map. Today only one key ("libraries") is
-///     supported, but this may be extended in the future to add more
-///     information on each target.
-///
-///   - The "libraries" entry contains details for how each platform library is
-///     implemented. The entry is a map, where keys are the name of the platform
-///     library and values contain details for where to find the implementation
-///     fo that library.
-///
-///   - The name of the library is a single token (e.g. "core") that matches the
-///     Uri path used after `dart:` (e.g. "dart:core").
-///
-///   - The "uri" entry on the library information is mandatory. The value is a
-///     string URI reference. The "patches" entry is optional and may have as a
-///     value a string URI reference or a list of URI references.
-///
-///     All URI references can either be a file URI or a relative URI path,
-///     which will be resolved relative to the location of the library
-///     specification file.
-///
-///
-/// Note: we currently have several different files that need to be updated
-/// when changing libraries, sources, and patch files:
-///    * .platform files (for dart2js)
-///    * .gypi files (for vm)
-///    * sdk_library_metadata/lib/libraries.dart (for analyzer, ddc)
-///
-/// we are in the process of unifying them all under this format (see
-/// https://github.com/dart-lang/sdk/issues/28836), but for now we need to pay
-/// close attention to change them consistently.
-
-// TODO(sigmund): move this file to a shared package.
-import 'dart:convert' show JSON;
-
-import '../fasta/util/relativize.dart';
-
-/// Contents from a single library specification file.
-///
-/// Contains information about all libraries on all target platforms defined in
-/// that file.
-class LibrariesSpecification {
-  final Map<String, TargetLibrariesSpecification> _targets;
-
-  const LibrariesSpecification(
-      [this._targets = const <String, TargetLibrariesSpecification>{}]);
-
-  /// The library specification for a given [target], or null if none is
-  /// available.
-  TargetLibrariesSpecification specificationFor(String target) =>
-      _targets[target];
-
-  /// Parse the given [json] as a library specification, resolving any relative
-  /// paths from [baseUri].
-  ///
-  /// May throw an exception if [json] is not properly formatted or contains
-  /// invalid values.
-  static LibrariesSpecification parse(Uri baseUri, String json) {
-    if (json == null) return const LibrariesSpecification();
-    var jsonData;
-    try {
-      var data = JSON.decode(json);
-      if (data is! Map) {
-        return _reportError('top-level specification is not a map');
-      }
-      jsonData = data as Map;
-    } on FormatException catch (e) {
-      throw new LibrariesSpecificationException(e);
-    }
-    var targets = <String, TargetLibrariesSpecification>{};
-    jsonData.forEach((String targetName, targetData) {
-      Map<String, LibraryInfo> libraries = <String, LibraryInfo>{};
-      if (targetData is! Map) {
-        return _reportError(
-            "target specification for '$targetName' is not a map");
-      }
-      if (!targetData.containsKey("libraries")) {
-        return _reportError("target specification "
-            "for '$targetName' doesn't have a libraries entry");
-      }
-      var librariesData = targetData["libraries"];
-      if (librariesData is! Map) {
-        return _reportError("libraries entry for '$targetName' is not a map");
-      }
-      librariesData.forEach((String name, data) {
-        if (data is! Map) {
-          return _reportError(
-              "library data for '$name' in target '$targetName' is not a map");
-        }
-        Uri checkAndResolve(uriString) {
-          if (uriString is! String) {
-            return _reportError("uri value '$uriString' is not a string"
-                "(from library '$name' in target '$targetName')");
-          }
-          var uri = Uri.parse(uriString);
-          if (uri.scheme != '' && uri.scheme != 'file') {
-            return _reportError("uri scheme in '$uriString' is not supported.");
-          }
-          return baseUri.resolveUri(uri);
-        }
-
-        var uri = checkAndResolve(data['uri']);
-        var patches;
-        if (data['patches'] is List) {
-          patches = data['patches'].map(baseUri.resolve).toList();
-        } else if (data['patches'] is String) {
-          patches = [checkAndResolve(data['patches'])];
-        } else if (data['patches'] == null) {
-          patches = const [];
-        } else {
-          return _reportError(
-              "patches entry for '$name' is not a list or a string");
-        }
-        libraries[name] = new LibraryInfo(name, uri, patches);
-      });
-      targets[targetName] =
-          new TargetLibrariesSpecification(targetName, libraries);
-    });
-    return new LibrariesSpecification(targets);
-  }
-
-  static _reportError(String error) =>
-      throw new LibrariesSpecificationException(error);
-
-  /// Serialize this specification to json.
-  ///
-  /// If possible serializes paths relative to [outputUri].
-  String toJsonString(Uri outputUri) => JSON.encode(toJsonMap(outputUri));
-
-  Map toJsonMap(Uri outputUri) {
-    var result = {};
-    var dir = outputUri.resolve('.');
-    String pathFor(Uri uri) => relativizeUri(uri, base: dir);
-    _targets.forEach((targetName, target) {
-      var libraries = {};
-      target._libraries.forEach((name, lib) {
-        libraries[name] = {
-          'uri': pathFor(lib.uri),
-          'patches': lib.patches.map(pathFor).toList(),
-        };
-      });
-      result[targetName] = {'libraries': libraries};
-    });
-    return result;
-  }
-}
-
-/// Specifies information about all libraries supported by a given target.
-class TargetLibrariesSpecification {
-  /// Name of the target platform.
-  final String targetName;
-
-  final Map<String, LibraryInfo> _libraries;
-
-  const TargetLibrariesSpecification(this.targetName,
-      [this._libraries = const <String, LibraryInfo>{}]);
-
-  /// Details about a library whose import is `dart:$name`.
-  LibraryInfo libraryInfoFor(String name) => _libraries[name];
-}
-
-/// Information about a `dart:` library in a specific target platform.
-class LibraryInfo {
-  /// The name of the library, which is the path developers use to import this
-  /// library (as `dart:$name`).
-  final String name;
-
-  /// The file defining the main implementation of the library.
-  final Uri uri;
-
-  /// Patch files used for this library in the target platform, if any.
-  final List<Uri> patches;
-
-  const LibraryInfo(this.name, this.uri, this.patches);
-}
-
-class LibrariesSpecificationException {
-  Object error;
-  LibrariesSpecificationException(this.error);
-
-  String toString() => '$error';
-}