Move pub into sdk/lib/_internal.

utils/tests/pub/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.
-
-library pub_update_test;
-
-import 'dart:async';
-import 'dart:io';
-
-import 'package:unittest/unittest.dart';
-
-import '../../pub/lock_file.dart';
-import '../../pub/package.dart';
-import '../../pub/pubspec.dart';
-import '../../pub/sdk.dart' as sdk;
-import '../../pub/source.dart';
-import '../../pub/source_registry.dart';
-import '../../pub/system_cache.dart';
-import '../../pub/utils.dart';
-import '../../pub/version.dart';
-import '../../pub/solver/version_solver.dart';
-import 'test_pub.dart';
-
-MockSource source1;
-MockSource source2;
-
-main() {
-  initConfig();
-
-  // Since this test isn't run from the SDK, it can't find the "version" file
-  // to load. Instead, just manually inject a version.
-  sdk.version = new Version(1, 2, 3);
-
-  group('basic graph', basicGraph);
-  group('with lockfile', withLockFile);
-  group('root dependency', rootDependency);
-  group('dev dependency', devDependency);
-  group('unsolvable', unsolvable);
-  group('backtracking', backtracking);
-  group('SDK constraint', sdkConstraint);
-}
-
-void basicGraph() {
-  testResolve('no dependencies', {
-    'myapp 0.0.0': {}
-  }, result: {
-    'myapp from root': '0.0.0'
-  });
-
-  testResolve('simple dependency tree', {
-    'myapp 0.0.0': {
-      'a': '1.0.0',
-      'b': '1.0.0'
-    },
-    'a 1.0.0': {
-      'aa': '1.0.0',
-      'ab': '1.0.0'
-    },
-    'aa 1.0.0': {},
-    'ab 1.0.0': {},
-    'b 1.0.0': {
-      'ba': '1.0.0',
-      'bb': '1.0.0'
-    },
-    'ba 1.0.0': {},
-    'bb 1.0.0': {}
-  }, result: {
-    'myapp from root': '0.0.0',
-    'a': '1.0.0',
-    'aa': '1.0.0',
-    'ab': '1.0.0',
-    'b': '1.0.0',
-    'ba': '1.0.0',
-    'bb': '1.0.0'
-  });
-
-  testResolve('shared dependency with overlapping constraints', {
-    'myapp 0.0.0': {
-      'a': '1.0.0',
-      'b': '1.0.0'
-    },
-    'a 1.0.0': {
-      'shared': '>=2.0.0 <4.0.0'
-    },
-    'b 1.0.0': {
-      'shared': '>=3.0.0 <5.0.0'
-    },
-    'shared 2.0.0': {},
-    'shared 3.0.0': {},
-    'shared 3.6.9': {},
-    'shared 4.0.0': {},
-    'shared 5.0.0': {},
-  }, result: {
-    'myapp from root': '0.0.0',
-    'a': '1.0.0',
-    'b': '1.0.0',
-    'shared': '3.6.9'
-  });
-
-  testResolve('shared dependency where dependent version in turn affects '
-              'other dependencies', {
-    'myapp 0.0.0': {
-      'foo': '<=1.0.2',
-      'bar': '1.0.0'
-    },
-    'foo 1.0.0': {},
-    'foo 1.0.1': { 'bang': '1.0.0' },
-    'foo 1.0.2': { 'whoop': '1.0.0' },
-    'foo 1.0.3': { 'zoop': '1.0.0' },
-    'bar 1.0.0': { 'foo': '<=1.0.1' },
-    'bang 1.0.0': {},
-    'whoop 1.0.0': {},
-    'zoop 1.0.0': {}
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '1.0.1',
-    'bar': '1.0.0',
-    'bang': '1.0.0'
-  }, maxTries: 2);
-
-  testResolve('circular dependency', {
-    'myapp 1.0.0': {
-      'foo': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'bar': '1.0.0'
-    },
-    'bar 1.0.0': {
-      'foo': '1.0.0'
-    }
-  }, result: {
-    'myapp from root': '1.0.0',
-    'foo': '1.0.0',
-    'bar': '1.0.0'
-  });
-}
-
-withLockFile() {
-  testResolve('with compatible locked dependency', {
-    'myapp 0.0.0': {
-      'foo': 'any'
-    },
-    'foo 1.0.0': { 'bar': '1.0.0' },
-    'foo 1.0.1': { 'bar': '1.0.1' },
-    'foo 1.0.2': { 'bar': '1.0.2' },
-    'bar 1.0.0': {},
-    'bar 1.0.1': {},
-    'bar 1.0.2': {}
-  }, lockfile: {
-    'foo': '1.0.1'
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '1.0.1',
-    'bar': '1.0.1'
-  });
-
-  testResolve('with incompatible locked dependency', {
-    'myapp 0.0.0': {
-      'foo': '>1.0.1'
-    },
-    'foo 1.0.0': { 'bar': '1.0.0' },
-    'foo 1.0.1': { 'bar': '1.0.1' },
-    'foo 1.0.2': { 'bar': '1.0.2' },
-    'bar 1.0.0': {},
-    'bar 1.0.1': {},
-    'bar 1.0.2': {}
-  }, lockfile: {
-    'foo': '1.0.1'
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '1.0.2',
-    'bar': '1.0.2'
-  });
-
-  testResolve('with unrelated locked dependency', {
-    'myapp 0.0.0': {
-      'foo': 'any'
-    },
-    'foo 1.0.0': { 'bar': '1.0.0' },
-    'foo 1.0.1': { 'bar': '1.0.1' },
-    'foo 1.0.2': { 'bar': '1.0.2' },
-    'bar 1.0.0': {},
-    'bar 1.0.1': {},
-    'bar 1.0.2': {},
-    'baz 1.0.0': {}
-  }, lockfile: {
-    'baz': '1.0.0'
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '1.0.2',
-    'bar': '1.0.2'
-  });
-
-  testResolve('unlocks dependencies if necessary to ensure that a new '
-      'dependency is satisfied', {
-    'myapp 0.0.0': {
-      'foo': 'any',
-      'newdep': 'any'
-    },
-    'foo 1.0.0': { 'bar': '<2.0.0' },
-    'bar 1.0.0': { 'baz': '<2.0.0' },
-    'baz 1.0.0': { 'qux': '<2.0.0' },
-    'qux 1.0.0': {},
-    'foo 2.0.0': { 'bar': '<3.0.0' },
-    'bar 2.0.0': { 'baz': '<3.0.0' },
-    'baz 2.0.0': { 'qux': '<3.0.0' },
-    'qux 2.0.0': {},
-    'newdep 2.0.0': { 'baz': '>=1.5.0' }
-  }, lockfile: {
-    'foo': '1.0.0',
-    'bar': '1.0.0',
-    'baz': '1.0.0',
-    'qux': '1.0.0'
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '2.0.0',
-    'bar': '2.0.0',
-    'baz': '2.0.0',
-    'qux': '1.0.0',
-    'newdep': '2.0.0'
-  }, maxTries: 3);
-}
-
-rootDependency() {
-  testResolve('with root source', {
-    'myapp 1.0.0': {
-      'foo': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'myapp from root': '>=1.0.0'
-    }
-  }, result: {
-    'myapp from root': '1.0.0',
-    'foo': '1.0.0'
-  });
-
-  testResolve('with different source', {
-    'myapp 1.0.0': {
-      'foo': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'myapp': '>=1.0.0'
-    }
-  }, result: {
-    'myapp from root': '1.0.0',
-    'foo': '1.0.0'
-  });
-
-  testResolve('with mismatched sources', {
-    'myapp 1.0.0': {
-      'foo': '1.0.0',
-      'bar': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'myapp': '>=1.0.0'
-    },
-    'bar 1.0.0': {
-      'myapp from mock2': '>=1.0.0'
-    }
-  }, error: sourceMismatch('foo', 'bar'));
-
-  testResolve('with wrong version', {
-    'myapp 1.0.0': {
-      'foo': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'myapp': '<1.0.0'
-    }
-  }, error: couldNotSolve);
-}
-
-devDependency() {
-  testResolve("includes root package's dev dependencies", {
-    'myapp 1.0.0': {
-      '(dev) foo': '1.0.0',
-      '(dev) bar': '1.0.0'
-    },
-    'foo 1.0.0': {},
-    'bar 1.0.0': {}
-  }, result: {
-    'myapp from root': '1.0.0',
-    'foo': '1.0.0',
-    'bar': '1.0.0'
-  });
-
-  testResolve("includes dev dependency's transitive dependencies", {
-    'myapp 1.0.0': {
-      '(dev) foo': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'bar': '1.0.0'
-    },
-    'bar 1.0.0': {}
-  }, result: {
-    'myapp from root': '1.0.0',
-    'foo': '1.0.0',
-    'bar': '1.0.0'
-  });
-
-  testResolve("ignores transitive dependency's dev dependencies", {
-    'myapp 1.0.0': {
-      'foo': '1.0.0'
-    },
-    'foo 1.0.0': {
-      '(dev) bar': '1.0.0'
-    },
-    'bar 1.0.0': {}
-  }, result: {
-    'myapp from root': '1.0.0',
-    'foo': '1.0.0'
-  });
-}
-
-unsolvable() {
-  testResolve('no version that matches requirement', {
-    'myapp 0.0.0': {
-      'foo': '>=1.0.0 <2.0.0'
-    },
-    'foo 2.0.0': {},
-    'foo 2.1.3': {}
-  }, error: noVersion(['myapp']));
-
-  testResolve('no version that matches combined constraint', {
-    'myapp 0.0.0': {
-      'foo': '1.0.0',
-      'bar': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'shared': '>=2.0.0 <3.0.0'
-    },
-    'bar 1.0.0': {
-      'shared': '>=2.9.0 <4.0.0'
-    },
-    'shared 2.5.0': {},
-    'shared 3.5.0': {}
-  }, error: noVersion(['foo', 'bar']));
-
-  testResolve('disjoint constraints', {
-    'myapp 0.0.0': {
-      'foo': '1.0.0',
-      'bar': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'shared': '<=2.0.0'
-    },
-    'bar 1.0.0': {
-      'shared': '>3.0.0'
-    },
-    'shared 2.0.0': {},
-    'shared 4.0.0': {}
-  }, error: disjointConstraint(['foo', 'bar']));
-
-  testResolve('mismatched descriptions', {
-    'myapp 0.0.0': {
-      'foo': '1.0.0',
-      'bar': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'shared-x': '1.0.0'
-    },
-    'bar 1.0.0': {
-      'shared-y': '1.0.0'
-    },
-    'shared-x 1.0.0': {},
-    'shared-y 1.0.0': {}
-  }, error: descriptionMismatch('foo', 'bar'));
-
-  testResolve('mismatched sources', {
-    'myapp 0.0.0': {
-      'foo': '1.0.0',
-      'bar': '1.0.0'
-    },
-    'foo 1.0.0': {
-      'shared': '1.0.0'
-    },
-    'bar 1.0.0': {
-      'shared from mock2': '1.0.0'
-    },
-    'shared 1.0.0': {},
-    'shared 1.0.0 from mock2': {}
-  }, error: sourceMismatch('foo', 'bar'));
-
-  testResolve('no valid solution', {
-    'myapp 0.0.0': {
-      'a': 'any',
-      'b': 'any'
-    },
-    'a 1.0.0': {
-      'b': '1.0.0'
-    },
-    'a 2.0.0': {
-      'b': '2.0.0'
-    },
-    'b 1.0.0': {
-      'a': '2.0.0'
-    },
-    'b 2.0.0': {
-      'a': '1.0.0'
-    }
-  }, error: couldNotSolve, maxTries: 4);
-}
-
-backtracking() {
-  testResolve('circular dependency on older version', {
-    'myapp 0.0.0': {
-      'a': '>=1.0.0'
-    },
-    'a 1.0.0': {},
-    'a 2.0.0': {
-      'b': '1.0.0'
-    },
-    'b 1.0.0': {
-      'a': '1.0.0'
-    }
-  }, result: {
-    'myapp from root': '0.0.0',
-    'a': '1.0.0'
-  }, maxTries: 2);
-
-  // The latest versions of a and b disagree on c. An older version of either
-  // will resolve the problem. This test validates that b, which is farther
-  // in the dependency graph from myapp is downgraded first.
-  testResolve('rolls back leaf versions first', {
-    'myapp 0.0.0': {
-      'a': 'any'
-    },
-    'a 1.0.0': {
-      'b': 'any'
-    },
-    'a 2.0.0': {
-      'b': 'any',
-      'c': '2.0.0'
-    },
-    'b 1.0.0': {},
-    'b 2.0.0': {
-      'c': '1.0.0'
-    },
-    'c 1.0.0': {},
-    'c 2.0.0': {}
-  }, result: {
-    'myapp from root': '0.0.0',
-    'a': '2.0.0',
-    'b': '1.0.0',
-    'c': '2.0.0'
-  }, maxTries: 2);
-
-  // Only one version of baz, so foo and bar will have to downgrade until they
-  // reach it.
-  testResolve('simple transitive', {
-    'myapp 0.0.0': {'foo': 'any'},
-    'foo 1.0.0': {'bar': '1.0.0'},
-    'foo 2.0.0': {'bar': '2.0.0'},
-    'foo 3.0.0': {'bar': '3.0.0'},
-    'bar 1.0.0': {'baz': 'any'},
-    'bar 2.0.0': {'baz': '2.0.0'},
-    'bar 3.0.0': {'baz': '3.0.0'},
-    'baz 1.0.0': {}
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '1.0.0',
-    'bar': '1.0.0',
-    'baz': '1.0.0'
-  }, maxTries: 3);
-
-  // This ensures it doesn't exhaustively search all versions of b when it's
-  // a-2.0.0 whose dependency on c-2.0.0-nonexistent led to the problem. We
-  // make sure b has more versions than a so that the solver tries a first
-  // since it sorts sibling dependencies by number of versions.
-  testResolve('backjump to nearer unsatisfied package', {
-    'myapp 0.0.0': {
-      'a': 'any',
-      'b': 'any'
-    },
-    'a 1.0.0': { 'c': '1.0.0' },
-    'a 2.0.0': { 'c': '2.0.0-nonexistent' },
-    'b 1.0.0': {},
-    'b 2.0.0': {},
-    'b 3.0.0': {},
-    'c 1.0.0': {},
-  }, result: {
-    'myapp from root': '0.0.0',
-    'a': '1.0.0',
-    'b': '3.0.0',
-    'c': '1.0.0'
-  }, maxTries: 2);
-
-  // Dependencies are ordered so that packages with fewer versions are tried
-  // first. Here, there are two valid solutions (either a or b must be
-  // downgraded once). The chosen one depends on which dep is traversed first.
-  // Since b has fewer versions, it will be traversed first, which means a will
-  // come later. Since later selections are revised first, a gets downgraded.
-  testResolve('traverse into package with fewer versions first', {
-    'myapp 0.0.0': {
-      'a': 'any',
-      'b': 'any'
-    },
-    'a 1.0.0': {'c': 'any'},
-    'a 2.0.0': {'c': 'any'},
-    'a 3.0.0': {'c': 'any'},
-    'a 4.0.0': {'c': 'any'},
-    'a 5.0.0': {'c': '1.0.0'},
-    'b 1.0.0': {'c': 'any'},
-    'b 2.0.0': {'c': 'any'},
-    'b 3.0.0': {'c': 'any'},
-    'b 4.0.0': {'c': '2.0.0'},
-    'c 1.0.0': {},
-    'c 2.0.0': {},
-  }, result: {
-    'myapp from root': '0.0.0',
-    'a': '4.0.0',
-    'b': '4.0.0',
-    'c': '2.0.0'
-  }, maxTries: 2);
-
-  // This sets up a hundred versions of foo and bar, 0.0.0 through 9.9.0. Each
-  // version of foo depends on a baz with the same major version. Each version
-  // of bar depends on a baz with the same minor version. There is only one
-  // version of baz, 0.0.0, so only older versions of foo and bar will
-  // satisfy it.
-  var map = {
-    'myapp 0.0.0': {
-      'foo': 'any',
-      'bar': 'any'
-    },
-    'baz 0.0.0': {}
-  };
-
-  for (var i = 0; i < 10; i++) {
-    for (var j = 0; j < 10; j++) {
-      map['foo $i.$j.0'] = {'baz': '$i.0.0'};
-      map['bar $i.$j.0'] = {'baz': '0.$j.0'};
-    }
-  }
-
-  testResolve('complex backtrack', map, result: {
-    'myapp from root': '0.0.0',
-    'foo': '0.9.0',
-    'bar': '9.0.0',
-    'baz': '0.0.0'
-  }, maxTries: 100);
-
-  // TODO(rnystrom): More tests. In particular:
-  // - Tests that demonstrate backtracking for every case that can cause a
-  //   solution to fail (no versions, disjoint, etc.)
-  // - Tests where there are multiple valid solutions and "best" is possibly
-  //   ambiguous to nail down which order the backtracker tries solutions.
-}
-
-sdkConstraint() {
-  var badVersion = '0.0.0-nope';
-  var goodVersion = sdk.version.toString();
-
-  testResolve('root matches SDK', {
-    'myapp 0.0.0': {'sdk': goodVersion }
-  }, result: {
-    'myapp from root': '0.0.0'
-  });
-
-  testResolve('root does not match SDK', {
-    'myapp 0.0.0': {'sdk': badVersion }
-  }, error: couldNotSolve);
-
-  testResolve('dependency does not match SDK', {
-    'myapp 0.0.0': {'foo': 'any'},
-    'foo 0.0.0': {'sdk': badVersion }
-  }, error: couldNotSolve);
-
-  testResolve('transitive dependency does not match SDK', {
-    'myapp 0.0.0': {'foo': 'any'},
-    'foo 0.0.0': {'bar': 'any'},
-    'bar 0.0.0': {'sdk': badVersion }
-  }, error: couldNotSolve);
-
-  testResolve('selects a dependency version that allows the SDK', {
-    'myapp 0.0.0': {'foo': 'any'},
-    'foo 1.0.0': {'sdk': goodVersion },
-    'foo 2.0.0': {'sdk': goodVersion },
-    'foo 3.0.0': {'sdk': badVersion },
-    'foo 4.0.0': {'sdk': badVersion }
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '2.0.0'
-  }, maxTries: 3);
-
-  testResolve('selects a transitive dependency version that allows the SDK', {
-    'myapp 0.0.0': {'foo': 'any'},
-    'foo 1.0.0': {'bar': 'any'},
-    'bar 1.0.0': {'sdk': goodVersion },
-    'bar 2.0.0': {'sdk': goodVersion },
-    'bar 3.0.0': {'sdk': badVersion },
-    'bar 4.0.0': {'sdk': badVersion }
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '1.0.0',
-    'bar': '2.0.0'
-  }, maxTries: 3);
-
-  testResolve('selects a dependency version that allows a transitive '
-              'dependency that allows the SDK', {
-    'myapp 0.0.0': {'foo': 'any'},
-    'foo 1.0.0': {'bar': '1.0.0'},
-    'foo 2.0.0': {'bar': '2.0.0'},
-    'foo 3.0.0': {'bar': '3.0.0'},
-    'foo 4.0.0': {'bar': '4.0.0'},
-    'bar 1.0.0': {'sdk': goodVersion },
-    'bar 2.0.0': {'sdk': goodVersion },
-    'bar 3.0.0': {'sdk': badVersion },
-    'bar 4.0.0': {'sdk': badVersion }
-  }, result: {
-    'myapp from root': '0.0.0',
-    'foo': '2.0.0',
-    'bar': '2.0.0'
-  }, maxTries: 3);
-
-  testResolve('ignores SDK constraints on bleeding edge', {
-    'myapp 0.0.0': {'sdk': badVersion }
-  }, result: {
-    'myapp from root': '0.0.0'
-  }, useBleedingEdgeSdkVersion: true);
-}
-
-testResolve(description, packages,
-            {lockfile, result, FailMatcherBuilder error, int maxTries,
-             bool useBleedingEdgeSdkVersion}) {
-  if (maxTries == null) maxTries = 1;
-  if (useBleedingEdgeSdkVersion == null) useBleedingEdgeSdkVersion = false;
-
-  test(description, () {
-    var cache = new SystemCache('.');
-    source1 = new MockSource('mock1');
-    source2 = new MockSource('mock2');
-    cache.register(source1);
-    cache.register(source2);
-    cache.sources.setDefault(source1.name);
-
-    // Build the test package graph.
-    var root;
-    packages.forEach((nameVersion, dependencies) {
-      var parsed = parseSource(nameVersion, (isDev, nameVersion, source) {
-        var parts = nameVersion.split(' ');
-        var name = parts[0];
-        var version = parts[1];
-
-        var package = mockPackage(name, version, dependencies);
-        if (name == 'myapp') {
-          // Don't add the root package to the server, so we can verify that Pub
-          // doesn't try to look up information about the local package on the
-          // remote server.
-          root = package;
-        } else {
-          source.addPackage(name, package);
-        }
-      });
-    });
-
-    // Clean up the expectation.
-    if (result != null) {
-      var newResult = {};
-      result.forEach((name, version) {
-        parseSource(name, (isDev, name, source) {
-          version = new Version.parse(version);
-          newResult[name] = new PackageId(name, source, version, name);
-        });
-      });
-      result = newResult;
-    }
-
-    var realLockFile = new LockFile.empty();
-    if (lockfile != null) {
-      lockfile.forEach((name, version) {
-        version = new Version.parse(version);
-        realLockFile.packages[name] =
-          new PackageId(name, source1, version, name);
-      });
-    }
-
-    // Make a version number like the continuous build's version.
-    var previousVersion = sdk.version;
-    if (useBleedingEdgeSdkVersion) {
-      sdk.version = new Version(0, 1, 2, build: '0_r12345_juser');
-    }
-
-    // Resolve the versions.
-    var future = resolveVersions(cache.sources, root,
-        lockFile: realLockFile);
-
-    var matcher;
-    if (result != null) {
-      matcher = new SolveSuccessMatcher(result, maxTries);
-    } else if (error != null) {
-      matcher = error(maxTries);
-    }
-
-    future = future.whenComplete(() {
-      if (useBleedingEdgeSdkVersion) {
-        sdk.version = previousVersion;
-      }
-    });
-
-    expect(future, completion(matcher));
-  });
-}
-
-typedef SolveFailMatcher FailMatcherBuilder(int maxTries);
-
-FailMatcherBuilder noVersion(List<String> packages) {
-  return (maxTries) => new SolveFailMatcher(packages, maxTries,
-      NoVersionException);
-}
-
-FailMatcherBuilder disjointConstraint(List<String> packages) {
-  return (maxTries) => new SolveFailMatcher(packages, maxTries,
-      DisjointConstraintException);
-}
-
-FailMatcherBuilder descriptionMismatch(String package1, String package2) {
-  return (maxTries) => new SolveFailMatcher([package1, package2], maxTries,
-      DescriptionMismatchException);
-}
-
-// If no solution can be found, the solver just reports the last failure that
-// happened during propagation. Since we don't specify the order that solutions
-// are tried, this just validates that *some* failure occurred, but not which.
-SolveFailMatcher couldNotSolve(maxTries) =>
-    new SolveFailMatcher([], maxTries, null);
-
-FailMatcherBuilder sourceMismatch(String package1, String package2) {
-  return (maxTries) => new SolveFailMatcher([package1, package2], maxTries,
-      SourceMismatchException);
-}
-
-class SolveSuccessMatcher implements Matcher {
-  /// The expected concrete package selections.
-  final Map<String, PackageId> _expected;
-
-  /// The maximum number of attempts that should have been tried before finding
-  /// the solution.
-  final int _maxTries;
-
-  SolveSuccessMatcher(this._expected, this._maxTries);
-
-  Description describe(Description description) {
-    return description.add(
-        'Solver to use at most $_maxTries attempts to find:\n'
-        '${_listPackages(_expected.values)}');
-  }
-
-  Description describeMismatch(SolveResult result,
-                               Description description,
-                               MatchState state, bool verbose) {
-    if (!result.succeeded) {
-      description.add('Solver failed with:\n${result.error}');
-      return;
-    }
-
-    description.add('Resolved:\n${_listPackages(result.packages)}\n');
-    description.add(state.state);
-    return description;
-  }
-
-  bool matches(SolveResult result, MatchState state) {
-    if (!result.succeeded) return false;
-
-    var expected = new Map.from(_expected);
-    var failures = new StringBuffer();
-
-    for (var id in result.packages) {
-      if (!expected.containsKey(id.name)) {
-        failures.writeln('Should not have selected $id');
-      } else {
-        var expectedId = expected.remove(id.name);
-        if (id != expectedId) {
-          failures.writeln('Expected $expectedId, not $id');
-        }
-      }
-    }
-
-    if (!expected.isEmpty) {
-      failures.writeln('Missing:\n${_listPackages(expected.values)}');
-    }
-
-    // Allow 1 here because the greedy solver will only make one attempt.
-    if (result.attemptedSolutions != 1 &&
-        result.attemptedSolutions != _maxTries) {
-      failures.writeln('Took ${result.attemptedSolutions} attempts');
-    }
-
-    if (!failures.isEmpty) {
-      state.state = failures.toString();
-      return false;
-    }
-
-    return true;
-  }
-
-  String _listPackages(Iterable<PackageId> packages) {
-    return '- ${packages.join('\n- ')}';
-  }
-}
-
-class SolveFailMatcher implements Matcher {
-  /// The strings that should appear in the resulting error message.
-  // TODO(rnystrom): This seems to always be package names. Make that explicit.
-  final Iterable<String> _expected;
-
-  /// The maximum number of attempts that should be tried before failing.
-  final int _maxTries;
-
-  /// The concrete error type that should be found, or `null` if any
-  /// [SolveFailure] is allowed.
-  final Type _expectedType;
-
-  SolveFailMatcher(this._expected, this._maxTries, this._expectedType);
-
-  Description describe(Description description) {
-    description.add('Solver should fail after at most $_maxTries attempts.');
-    if (!_expected.isEmpty) {
-      var textList = _expected.map((s) => '"$s"').join(", ");
-      description.add(' The error should contain $textList.');
-    }
-    return description;
-  }
-
-  Description describeMismatch(SolveResult result,
-                               Description description,
-                               MatchState state, bool verbose) {
-    description.add(state.state);
-    return description;
-  }
-
-  bool matches(SolveResult result, MatchState state) {
-    var failures = new StringBuffer();
-
-    if (result.succeeded) {
-      failures.writeln('Solver succeeded');
-    } else {
-      if (_expectedType != null && result.error.runtimeType != _expectedType) {
-        failures.writeln('Should have error type $_expectedType, got '
-            '${result.error.runtimeType}');
-      }
-
-      var message = result.error.toString();
-      for (var expected in _expected) {
-        if (!message.contains(expected)) {
-          failures.writeln(
-              'Expected error to contain "$expected", got:\n$message');
-        }
-      }
-
-      // Allow 1 here because the greedy solver will only make one attempt.
-      if (result.attemptedSolutions != 1 &&
-          result.attemptedSolutions != _maxTries) {
-        failures.writeln('Took ${result.attemptedSolutions} attempts');
-      }
-    }
-
-    if (!failures.isEmpty) {
-      state.state = failures.toString();
-      return false;
-    }
-
-    return true;
-  }
-}
-
-/// A source used for testing. This both creates mock package objects and acts
-/// as a source for them.
-///
-/// In order to support testing packages that have the same name but different
-/// descriptions, a package's name is calculated by taking the description
-/// string and stripping off any trailing hyphen followed by non-hyphen
-/// characters.
-class MockSource extends Source {
-  final _packages = <String, Map<Version, Package>>{};
-
-  /// Keeps track of which package version lists have been requested. Ensures
-  /// that a source is only hit once for a given package and that pub
-  /// internally caches the results.
-  final _requestedVersions = new Set<String>();
-
-  /// Keeps track of which package pubspecs have been requested. Ensures that a
-  /// source is only hit once for a given package and that pub internally
-  /// caches the results.
-  final _requestedPubspecs = new Map<String, Set<Version>>();
-
-  final String name;
-  bool get shouldCache => true;
-
-  MockSource(this.name);
-
-  Future<String> systemCacheDirectory(PackageId id) {
-    return new Future.value('${id.name}-${id.version}');
-  }
-
-  Future<List<Version>> getVersions(String name, String description) {
-    return new Future.sync(() {
-      // Make sure the solver doesn't request the same thing twice.
-      if (_requestedVersions.contains(description)) {
-        throw new Exception('Version list for $description was already '
-            'requested.');
-      }
-
-      _requestedVersions.add(description);
-
-      if (!_packages.containsKey(description)){
-        throw new Exception('MockSource does not have a package matching '
-            '"$description".');
-      }
-      return _packages[description].keys.toList();
-    });
-  }
-
-  Future<Pubspec> describe(PackageId id) {
-    return new Future.sync(() {
-      // Make sure the solver doesn't request the same thing twice.
-      if (_requestedPubspecs.containsKey(id.description) &&
-          _requestedPubspecs[id.description].contains(id.version)) {
-        throw new Exception('Pubspec for $id was already requested.');
-      }
-
-      _requestedPubspecs.putIfAbsent(id.description, () => new Set<Version>());
-      _requestedPubspecs[id.description].add(id.version);
-
-      return _packages[id.description][id.version].pubspec;
-    });
-  }
-
-  Future<bool> install(PackageId id, String path) {
-    throw new Exception('no');
-  }
-
-  void addPackage(String description, Package package) {
-    _packages.putIfAbsent(description, () => new Map<Version, Package>());
-    _packages[description][package.version] = package;
-  }
-}
-
-Package mockPackage(String description, String version,
-                    Map dependencyStrings) {
-  var sdkConstraint = null;
-
-  // Build the pubspec dependencies.
-  var dependencies = <PackageRef>[];
-  var devDependencies = <PackageRef>[];
-
-  dependencyStrings.forEach((name, constraint) {
-    parseSource(name, (isDev, name, source) {
-      var packageName = name.replaceFirst(new RegExp(r"-[^-]+$"), "");
-      constraint = new VersionConstraint.parse(constraint);
-
-      if (name == 'sdk') {
-        sdkConstraint = constraint;
-        return;
-      }
-
-      var ref = new PackageRef(packageName, source, constraint, name);
-
-      if (isDev) {
-        devDependencies.add(ref);
-      } else {
-        dependencies.add(ref);
-      }
-    });
-  });
-
-  var name = description.replaceFirst(new RegExp(r"-[^-]+$"), "");
-  var pubspec = new Pubspec(
-      name, new Version.parse(version), dependencies, devDependencies,
-      new PubspecEnvironment(sdkConstraint));
-  return new Package.inMemory(pubspec);
-}
-
-void parseSource(String description,
-    callback(bool isDev, String name, Source source)) {
-  var isDev = false;
-
-  if (description.startsWith("(dev) ")) {
-    description = description.substring("(dev) ".length);
-    isDev = true;
-  }
-
-  var name = description;
-  var source = source1;
-
-  var sourceNames = {
-    'mock1': source1,
-    'mock2': source2,
-    'root': null
-  };
-
-  var match = new RegExp(r"(.*) from (.*)").firstMatch(description);
-  if (match != null) {
-    name = match[1];
-    source = sourceNames[match[2]];
-  }
-
-  callback(isDev, name, source);
-}