Add fasta subdirectories to subpackage_relationships_test.

pkg/front_end/test/subpackage_relationships_test.dart

 // 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.
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:front_end/compiler_options.dart';
 import 'package:front_end/dependency_grapher.dart';
 import 'package:path/path.dart' as pathos;
 
 main() async {
   exit(await new _SubpackageRelationshipsTest().run());
 }
 
 /// Map from subpackage name to the rules for what the subpackage is allowed to
 /// depend directly on.
 ///
-/// Each subdirectory of `lib/src` is considered a subpackage.  Files in
-/// `lib/src` but not in a subdirectory are considered to be in the `lib/src`
-/// subpackage.  Files outside of `lib/src` (but still in `lib`) are considered
-/// to be in the `lib` subpackage.
+/// Each listed directory is considered a subpackage.  Each package contains all
+/// of its descendant files that are not in a more deeply nested subpackage.
 ///
 /// TODO(paulberry): stuff in lib/src shouldn't depend on lib; lib should just
 /// re-export stuff in lib/src.
 /// TODO(paulberry): remove dependencies on analyzer.
 final subpackageRules = {
   'lib': new SubpackageRules(
       mayImportAnalyzer: true,
       allowedDependencies: ['lib/src', 'lib/src/base']),
   'lib/src': new SubpackageRules(
       mayImportAnalyzer: true,
       allowedDependencies: ['lib', 'lib/src/base', 'lib/src/scanner']),
   'lib/src/base': new SubpackageRules(
       mayImportAnalyzer: true, allowedDependencies: ['lib']),
-  'lib/src/scanner': new SubpackageRules(allowedDependencies: ['lib/src/base']),
-  'lib/src/fasta': new SubpackageRules(mayImportAnalyzer: true),
+  'lib/src/fasta':
+      new SubpackageRules(mayImportAnalyzer: true, allowedDependencies: [
+    'lib/src/fasta/builder',
+    'lib/src/fasta/dill',
+    'lib/src/fasta/kernel',
+    'lib/src/fasta/parser',
+    'lib/src/fasta/scanner',
+    'lib/src/fasta/testing',
+  ]),
+  'lib/src/fasta/analyzer':
+      new SubpackageRules(mayImportAnalyzer: true, allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/builder',
+    'lib/src/fasta/dill',
+    'lib/src/fasta/kernel',
+    'lib/src/fasta/scanner',
+    'lib/src/fasta/source',
+  ]),
+  'lib/src/fasta/bin': new SubpackageRules(allowedDependencies: [
+    'lib/src/fasta',
+  ]),
+  'lib/src/fasta/builder': new SubpackageRules(allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/dill',
+    'lib/src/fasta/parser',
+    'lib/src/fasta/source',
+  ]),
+  'lib/src/fasta/dill': new SubpackageRules(allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/kernel',
+  ]),
+  'lib/src/fasta/kernel': new SubpackageRules(allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/builder',
+    'lib/src/fasta/dill',
+    'lib/src/fasta/parser',
+    'lib/src/fasta/scanner',
+    'lib/src/fasta/source',
+  ]),
+  'lib/src/fasta/parser':
+      new SubpackageRules(allowSubdirs: true, allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/scanner',
+    'lib/src/fasta/util',
+  ]),
+  'lib/src/fasta/scanner':
+      new SubpackageRules(allowSubdirs: true, allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/parser',
+    'lib/src/fasta/util',
+  ]),
+  'lib/src/fasta/source': new SubpackageRules(allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/analyzer',
+    'lib/src/fasta/builder',
+    'lib/src/fasta/dill',
+    'lib/src/fasta/kernel',
+    'lib/src/fasta/parser',
+    'lib/src/fasta/scanner',
+  ]),
+  'lib/src/fasta/testing':
+      new SubpackageRules(mayImportAnalyzer: true, allowedDependencies: [
+    'lib/src/fasta',
+    'lib/src/fasta/dill',
+    'lib/src/fasta/kernel',
+  ]),
+  'lib/src/fasta/util': new SubpackageRules(),
+  'lib/src/scanner': new SubpackageRules(allowedDependencies: [
+    'lib/src/base',
+  ]),
 };
 
 /// Rules for what a subpackage may depend directly on.
 class SubpackageRules {
   /// Indicates whether the subpackage may directly depend on analyzer.
   final bool mayImportAnalyzer;
 
+  /// Indicates whether dart files may exist in subdirectories of this
+  /// subpackage.
+  ///
+  /// If `false`, any subdirectory of this subpackage must be a separate
+  /// subpackage.
+  final bool allowSubdirs;
+
   /// Indicates which other subpackages a given subpackage may directly depend
   /// on.
   final List<String> allowedDependencies;
 
   SubpackageRules(
-      {this.mayImportAnalyzer: false, this.allowedDependencies: const []});
+      {this.mayImportAnalyzer: false,
+      this.allowSubdirs: false,
+      this.allowedDependencies: const []});
 }
 
 class _SubpackageRelationshipsTest {
   /// File uri of the front_end package's "lib" directory.
   final frontEndLibUri = Platform.script.resolve('../lib/');
 
   /// Indicates whether any problems have been reported yet.
   bool problemsReported = false;
 
   /// Check for problems resulting from URI [src] having a direct dependency on
@@ skipping 67 matching lines @@
     }
     return problemsReported ? 1 : 0;
   }
 
   /// Determines which subpackage [src] is in.
   ///
   /// If [src] is not part of the front end, `null` is returned.
   String subpackageForUri(Uri src) {
     if (src.scheme != 'package') return null;
     if (src.pathSegments[0] != 'front_end') return null;
-    if (src.pathSegments[1] != 'src') return 'lib';
-    if (src.pathSegments.length == 3) return 'lib/src';
-    return 'lib/src/${src.pathSegments[2]}';
+    var pathWithLib = 'lib/${src.pathSegments.skip(1).join('/')}';
+    String subpackage;
+    String pathWithinSubpackage;
+    for (var subpackagePath in subpackageRules.keys) {
+      var subpackagePathWithSlash = '$subpackagePath/';
+      if (pathWithLib.startsWith(subpackagePathWithSlash) &&
+          (subpackage == null || subpackage.length < subpackagePath.length)) {
+        subpackage = subpackagePath;
+        pathWithinSubpackage =
+            pathWithLib.substring(subpackagePathWithSlash.length);
+      }
+    }
+    if (subpackage == null) {
+      problem('Uri $src is inside package:front_end but is not in any known '
+          'subpackage');
+    } else if (!subpackageRules[subpackage].allowSubdirs &&
+        pathWithinSubpackage.contains('/')) {
+      problem('Uri $src is in a subfolder of $subpackage, but that '
+          'subpackage does not allow dart files in subdirectories.');
+    }
+    return subpackage;
   }
 }