Track Source objects in PackageNames.

lib/src/solver/backtracking_solver.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.
 
 /// A back-tracking depth-first solver.
 ///
 /// Attempts to find the best solution for a root package's transitive
 /// dependency graph, where a "solution" is a set of concrete package versions.
 /// A valid solution will select concrete versions for every package reached
 /// from the root package's dependency graph, and each of those packages will
@@ skipping 213 matching lines @@
   ///
   /// Returns `null` if it isn't in the lockfile (or has been unlocked).
   PackageId getLocked(String package) {
     if (type == SolveType.GET) return lockFile.packages[package];
 
     // When downgrading, we don't want to force the latest versions of
     // non-hosted packages, since they don't support multiple versions and thus
     // can't be downgraded.
     if (type == SolveType.DOWNGRADE) {
       var locked = lockFile.packages[package];
-      if (locked != null &&
-          !systemCache.sources[locked.source].hasMultipleVersions) {
-        return locked;
-      }
+      if (locked != null && !locked.source.hasMultipleVersions) return locked;
     }
 
     if (_forceLatest.isEmpty || _forceLatest.contains(package)) return null;
     return lockFile.packages[package];
   }
 
   /// Gets the package [name] that's currently contained in the lockfile if it
   /// matches the current constraint and has the same source and description as
   /// other references to that package.
   ///
   /// Returns `null` otherwise.
   PackageId _getValidLocked(String name) {
     var package = getLocked(name);
     if (package == null) return null;
 
     var constraint = _selection.getConstraint(name);
     if (!constraint.allows(package.version)) {
       logSolve('$package is locked but does not match $constraint');
       return null;
     } else {
       logSolve('$package is locked');
     }
 
     var required = _selection.getRequiredDependency(name);
-    if (required != null) {
-      if (package.source != required.dep.source) return null;
-
-      var source = systemCache.sources[package.source];
-      if (!source.descriptionsEqual(
-          package.description, required.dep.description)) return null;
-    }
+    if (required != null && !package.samePackage(required.dep)) return null;
 
     return package;
   }
 
   /// Tries to find the best set of versions that meet the constraints.
   ///
   /// Selects matching versions of unselected packages, or backtracks if there
   /// are no such versions.
   Future<List<PackageId>> _solve() async {
     // TODO(nweiz): Use real while loops when issue 23394 is fixed.
@@ skipping 250 matching lines @@
           _fail(otherDep.depender.name);
         }
 
         logSolve(
             'inconsistent source "${dep.source}" for ${dep.name}:\n'
             '  $dependency\n' +
                 _selection.describeDependencies(dep.name));
         throw new SourceMismatchException(dep.name, allDeps);
       }
 
-      var source = systemCache.sources[dep.source];
-      if (!source.descriptionsEqual(
-          dep.description, required.dep.description)) {
+      if (!dep.samePackage(required.dep)) {
         // Mark the dependers as failing rather than the package itself, because
         // no version with this description will be compatible.
         for (var otherDep in _selection.getDependenciesOn(dep.name)) {
           _fail(otherDep.depender.name);
         }
 
         logSolve(
             'inconsistent description "${dep.description}" for ${dep.name}:\n'
             '  $dependency\n' +
                 _selection.describeDependencies(dep.name));
@@ skipping 36 matching lines @@
         // Not overridden.
         return dep;
       }).toSet();
     } else {
       // Ignore any overridden dependencies.
       deps.removeWhere((dep) => _overrides.containsKey(dep.name));
     }
 
     // Make sure the package doesn't have any bad dependencies.
     for (var dep in deps.toSet()) {
-      if (!dep.isRoot && systemCache.sources[dep.source] is UnknownSource) {
+      if (!dep.isRoot && dep.source is UnknownSource) {
         throw new UnknownSourceException(id.name, [new Dependency(id, dep)]);
       }
 
       if (dep.name == 'barback') {
         deps.add(new PackageDep.magic('pub itself'));
       }
     }
 
     return deps;
   }
@@ skipping 49 matching lines @@
   void _validateSdkConstraint(Pubspec pubspec) {
     if (_overrides.containsKey(pubspec.name)) return;
     if (pubspec.environment.sdkVersion.allows(sdk.version)) return;
 
     throw new BadSdkVersionException(pubspec.name,
         'Package ${pubspec.name} requires SDK version '
         '${pubspec.environment.sdkVersion} but the current SDK is '
         '${sdk.version}.');
   }
 }