Create a package to hold code shared between front_end and analyzer.

Previously such shared code was in the front_end package, but that
created problems because there is a lot of code in front_end that
isn't intended to be shared with the analyzer (including, notably, the
dependency on kernel).

This CL just moves over the flow_analysis logic to the new shared
package.  Follow-up CLs will move over other shared logic and tests.
The end goal is that the analyzer package will no longer have a
dependency on front_end.

Change-Id: I5642d6565204422d79808ca47648462db85e442a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/123624
Reviewed-by: Jens Johansen <jensj@google.com>

.packages

@@ -6,6 +6,7 @@
 # by DEPS into /third_party/pkg and /third_party/pkg_tested.
 # Please update this file if you add a package to DEPS or /pkg
 #
+_fe_analyzer_shared:pkg/_fe_analyzer_shared/lib
 analysis_server:pkg/analysis_server/lib
 analysis_server_client:pkg/analysis_server_client/lib
 analysis_tool:pkg/analysis_tool/lib

pkg/_fe_analyzer_shared/LICENSE

@@ -0,0 +1,26 @@
+Copyright 2019, the Dart project authors. All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+    * Neither the name of Google Inc. nor the names of its
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

pkg/_fe_analyzer_shared/README.md

@@ -0,0 +1,10 @@
+# FE/analyzer shared code
+
+This package contains logic that is shared between the front_end and
+analyzer packages.  It is intended solely to facilitate development of
+the Dart SDK, and is not intended for use by end users.  In
+particular, this package has no public API, so no guarantee is made of
+compatibility between one version of the package and the next.
+
+End users should consider using the analyzer package to analyze Dart
+source code.

pkg/_fe_analyzer_shared/analysis_options.yaml

@@ -0,0 +1,20 @@
+# Copyright (c) 2019, 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.
+
+include: analysis_options_no_lints.yaml
+
+linter:
+  rules:
+    - curly_braces_in_flow_control_structures
+    - prefer_adjacent_string_concatenation
+    - unawaited_futures
+    - recursive_getters
+    - avoid_empty_else
+    - empty_statements
+    - list_remove_unrelated_type
+    - iterable_contains_unrelated_type
+    - valid_regexps
+    - package_api_docs
+    - lines_longer_than_80_chars
+    # - always_specify_types

pkg/_fe_analyzer_shared/analysis_options_no_lints.yaml

@@ -0,0 +1,8 @@
+# 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.
+
+analyzer:
+  errors:
+    # Allow having TODOs in the code
+    todo: ignore

pkg/_fe_analyzer_shared/pubspec.yaml

@@ -0,0 +1,10 @@
+name: _fe_analyzer_shared
+version: 1.0.0
+author: Dart Team <misc@dartlang.org>
+description: Logic that is shared between the front_end and analyzer packages.
+homepage: https://github.com/dart-lang/sdk/tree/master/pkg/_fe_analyzer_shared
+
+environment:
+  sdk: '>=2.2.2 <3.0.0'
+dependencies:
+  meta: ^1.0.2

pkg/analyzer/lib/src/dart/resolver/flow_analysis_visitor.dart

@@ -2,6 +2,7 @@
 // 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:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
@@ -11,7 +12,6 @@ import 'package:analyzer/dart/element/type_system.dart';
 import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/generated/type_system.dart' show Dart2TypeSystem;
 import 'package:analyzer/src/generated/variable_type_provider.dart';
-import 'package:front_end/src/fasta/flow_analysis/flow_analysis.dart';
 
 /// Data gathered by flow analysis, retained for testing purposes.
 class FlowAnalysisDataForTesting {

pkg/analyzer/pubspec.yaml

@@ -8,6 +8,7 @@ environment:
   sdk: '>=2.2.2 <3.0.0'
 
 dependencies:
+  _fe_analyzer_shared: 1.0.0
   args: '>=0.12.1 <2.0.0'
   charcode: ^1.1.0
   collection: ^1.10.1

pkg/analyzer/test/id_tests/assigned_variables_test.dart

@@ -4,12 +4,12 @@
 
 import 'dart:io';
 
+import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/dart/analysis/testing_data.dart';
 import 'package:analyzer/src/dart/resolver/flow_analysis_visitor.dart';
 import 'package:analyzer/src/util/ast_data_extractor.dart';
-import 'package:front_end/src/fasta/flow_analysis/flow_analysis.dart';
 import 'package:front_end/src/testing/id.dart' show ActualData, Id;
 import 'package:front_end/src/testing/id_testing.dart';
 

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

@@ -6,6 +6,7 @@ library fasta.body_builder;
 
 import 'dart:core' hide MapEntry;
 
+import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:kernel/ast.dart';
 import 'package:kernel/type_environment.dart';
 
@@ -42,8 +43,6 @@ import '../fasta_codes.dart' as fasta;
 
 import '../fasta_codes.dart' show LocatedMessage, Message, noLength, Template;
 
-import '../flow_analysis/flow_analysis.dart';
-
 import '../identifiers.dart'
     show
         Identifier,

pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart

@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
+import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
+
 import 'package:kernel/ast.dart'
     show
         Constructor,
@@ -30,8 +32,6 @@ import '../../base/instrumentation.dart' show Instrumentation;
 
 import '../builder/library_builder.dart';
 
-import '../flow_analysis/flow_analysis.dart';
-
 import '../kernel/forest.dart';
 
 import '../kernel/kernel_builder.dart'

pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart

@@ -4,6 +4,8 @@
 
 import 'dart:core' hide MapEntry;
 
+import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
+
 import 'package:front_end/src/fasta/kernel/kernel_shadow_ast.dart';
 
 import 'package:kernel/ast.dart' hide Variance;
@@ -30,8 +32,6 @@ import '../builder/member_builder.dart';
 
 import '../fasta_codes.dart';
 
-import '../flow_analysis/flow_analysis.dart';
-
 import '../kernel/expression_generator.dart' show buildIsNull;
 
 import '../kernel/kernel_shadow_ast.dart'

pkg/front_end/pubspec.yaml

@@ -8,6 +8,7 @@ homepage: https://github.com/dart-lang/sdk/tree/master/pkg/front_end
 environment:
   sdk: '>=2.2.2 <3.0.0'
 dependencies:
+  _fe_analyzer_shared: 1.0.0
   kernel: 0.3.28
   package_config: '^1.1.0'
   meta: ^1.0.2

pkg/front_end/test/deps_test.dart

@@ -75,8 +75,10 @@ Future<void> main() async {
   Set<Uri> otherNonDartUris = new Set<Uri>();
   Set<Uri> frontEndUris = new Set<Uri>();
   Set<Uri> kernelUris = new Set<Uri>();
+  Set<Uri> feAnalyzerSharedUris = new Set<Uri>();
   Set<Uri> dartPlatformUris = new Set<Uri>();
   Uri kernelUri = repoDir.resolve("pkg/kernel/");
+  Uri feAnalyzerSharedUri = repoDir.resolve("pkg/_fe_analyzer_shared/");
   Uri platformUri1 = repoDir.resolve("sdk/lib/");
   Uri platformUri2 = repoDir.resolve("runtime/lib/");
   Uri platformUri3 = repoDir.resolve("runtime/bin/");
@@ -85,6 +87,8 @@ Future<void> main() async {
       frontEndUris.add(uri);
     } else if (uri.toString().startsWith(kernelUri.toString())) {
       kernelUris.add(uri);
+    } else if (uri.toString().startsWith(feAnalyzerSharedUri.toString())) {
+      feAnalyzerSharedUris.add(uri);
     } else if (uri.toString().startsWith(platformUri1.toString()) ||
         uri.toString().startsWith(platformUri2.toString()) ||
         uri.toString().startsWith(platformUri3.toString())) {

pkg/front_end/test/fasta/flow_analysis/assigned_variables_test.dart

@@ -2,7 +2,7 @@
 // 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:front_end/src/fasta/flow_analysis/flow_analysis.dart';
+import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:test/test.dart';
 
 main() {

pkg/front_end/test/fasta/flow_analysis/flow_analysis_test.dart

@@ -2,7 +2,7 @@
 // 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:front_end/src/fasta/flow_analysis/flow_analysis.dart';
+import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:meta/meta.dart';
 import 'package:test/test.dart';
 

pkg/front_end/test/flow_analysis/assigned_variables/assigned_variables_test.dart

@@ -3,9 +3,11 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:io' show Directory, Platform;
+
+import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:front_end/src/api_prototype/experimental_flags.dart'
     show ExperimentalFlag;
-import 'package:front_end/src/fasta/flow_analysis/flow_analysis.dart';
+import 'package:front_end/src/fasta/builder/member_builder.dart';
 import 'package:front_end/src/fasta/source/source_loader.dart';
 
 import 'package:front_end/src/testing/id.dart' show ActualData, Id, IdKind;
@@ -13,7 +15,6 @@ import 'package:front_end/src/testing/id_testing.dart'
     show DataInterpreter, runTests;
 import 'package:front_end/src/testing/id_testing.dart';
 import 'package:front_end/src/testing/id_testing_helper.dart';
-import 'package:front_end/src/fasta/builder/member_builder.dart';
 import 'package:front_end/src/testing/id_testing_utils.dart';
 import 'package:kernel/ast.dart' hide Variance;
 

pkg/nnbd_migration/lib/src/decorated_type_operations.dart

@@ -2,9 +2,9 @@
 // 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:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type_system.dart';
-import 'package:front_end/src/fasta/flow_analysis/flow_analysis.dart';
 import 'package:nnbd_migration/src/decorated_type.dart';
 import 'package:nnbd_migration/src/node_builder.dart';
 import 'package:nnbd_migration/src/nullability_node.dart';

pkg/nnbd_migration/lib/src/edge_builder.dart

@@ -2,6 +2,7 @@
 // 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:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
@@ -13,7 +14,6 @@ import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/dart/resolver/flow_analysis_visitor.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
-import 'package:front_end/src/fasta/flow_analysis/flow_analysis.dart';
 import 'package:meta/meta.dart';
 import 'package:nnbd_migration/instrumentation.dart';
 import 'package:nnbd_migration/nnbd_migration.dart';

pkg/nnbd_migration/lib/src/fix_builder.dart

@@ -2,6 +2,7 @@
 // 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:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
@@ -15,7 +16,6 @@ import 'package:analyzer/src/dart/element/type_provider.dart';
 import 'package:analyzer/src/dart/resolver/flow_analysis_visitor.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
-import 'package:front_end/src/fasta/flow_analysis/flow_analysis.dart';
 import 'package:meta/meta.dart';
 import 'package:nnbd_migration/src/decorated_class_hierarchy.dart';
 import 'package:nnbd_migration/src/utilities/resolution_utils.dart';

pkg/nnbd_migration/pubspec.yaml

@@ -3,4 +3,5 @@ publish_to: none
 environment:
   sdk: '>=2.2.2 <3.0.0'
 dependencies:
+  _fe_analyzer_shared: 1.0.0
   analyzer: ^0.37.0

tools/bots/test_matrix.json

@@ -180,6 +180,7 @@
       "third_party/pkg_tested/",
       "third_party/observatory_pub_packages/packages/",
       "tools/sdks/dart-sdk/",
+      "pkg/_fe_analyzer_shared/",
       "pkg/async_helper/",
       "pkg/build_integration/",
       "pkg/dart_internal/",
@@ -254,6 +255,7 @@
       "tests/search/",
       "tests/standalone_2/",
       "tests/ffi/",
+      "pkg/_fe_analyzer_shared/",
       "pkg/async_helper/",
       "pkg/build_integration/",
       "pkg/dart_internal/",