Improve circular dependency overrides.

test/version_solver_test.dart

 // Copyright (c) 2012, 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 'package:path/path.dart' as p;
 import 'package:scheduled_test/scheduled_test.dart';
 
 import 'package:pub/src/lock_file.dart';
@@ skipping 1198 matching lines @@
         'dependency_overrides': {'foo': '>=1.0.0 <2.0.0'}
       })
     ]).create();
 
     expectResolves(
         error: 'Package foo has no versions that match >=1.0.0 <2.0.0 derived '
                  'from:\n'
                '- myapp depends on version >=1.0.0 <2.0.0');
   });
 
-  integration('override a bad source without error', () {
+  integration('overrides a bad source without error', () {
     servePackages((builder) {
       builder.serve('foo', '0.0.0');
     });
 
     d.dir(appPath, [
       d.pubspec({
         'name': 'myapp',
         'dependencies': {'foo': {'bad': 'any'}},
         'dependency_overrides': {'foo': 'any'}
       })
     ]).create();
 
     expectResolves(result: {'foo': '0.0.0'});
   });
+
+  integration('overrides an unmatched root dependency', () {
+    servePackages((builder) {
+      builder.serve('foo', '0.0.0', deps: {'myapp': '1.0.0'});
+    });
+
+    d.dir(appPath, [
+      d.pubspec({
+        'name': 'myapp',
+        'version': '2.0.0',
+        'dependency_overrides': {'foo': 'any'}
+      })
+    ]).create();
+
+    expectResolves(result: {'foo': '0.0.0'});
+  });
 }
 
 void downgrade() {
   integration("downgrades a dependency to the lowest matching version", () {
     servePackages((builder) {
       builder.serve('foo', '1.0.0');
       builder.serve('foo', '2.0.0-dev');
       builder.serve('foo', '2.0.0');
       builder.serve('foo', '2.1.0');
     });
@@ skipping 69 matching lines @@
         dep = registry.hosted
             .refFor(dep.name, url: await globalPackageServer.url)
             .withConstraint(dep.constraint);
       }
       expect(dep.allows(id), isTrue, reason: "Expected $id to match $dep.");
     }
 
     expect(ids, isEmpty, reason: "Expected no additional packages.");
   });
 }