Notify about existing caches when preloading (#122592)

packages/flutter_tools/lib/src/dart/pub.dart

@@ -34,28 +34,6 @@ const String _kPubCacheEnvironmentKey = 'PUB_CACHE';
 
 typedef MessageFilter = String? Function(String message);
 
-/// Load any package-files stored in [preloadCacheDir] into the pub cache if it
-/// exists.
-///
-/// Deletes the [preloadCacheDir].
-@visibleForTesting
-void preloadPubCache({
-  required Directory preloadCacheDir,
-  required ProcessManager processManager,
-  required Logger logger,
-  required List<String> pubCommand,
-}) {
-  if (preloadCacheDir.existsSync()) {
-    final Iterable<String> cacheFiles =
-          preloadCacheDir
-            .listSync()
-            .map((FileSystemEntity f) => f.path)
-            .where((String path) => path.endsWith('.tar.gz'));
-    processManager.runSync(<String>[...pubCommand, 'cache', 'preload',...cacheFiles]);
-    _tryDeleteDirectory(preloadCacheDir, logger);
-  }
-}
-
 bool _tryDeleteDirectory(Directory directory, Logger logger) {
   try {
     if (directory.existsSync()) {
@@ -614,14 +592,77 @@ class _DefaultPub implements Pub {
     if (_platform.environment.containsKey(_kPubCacheEnvironmentKey)) {
       return _platform.environment[_kPubCacheEnvironmentKey];
     }
+    _preloadPubCache();
+    // Use pub's default location by returning null.
+    return null;
+  }
 
+  /// Load any package-files stored in FLUTTER_ROOT/.pub-preload-cache into the
+  /// pub cache if it exists.
+  ///
+  /// Deletes the [preloadCacheDir].
+  void _preloadPubCache() {
     final String flutterRootPath = Cache.flutterRoot!;
     final Directory flutterRoot = _fileSystem.directory(flutterRootPath);
     final Directory preloadCacheDir = flutterRoot.childDirectory('.pub-preload-cache');
-    preloadPubCache(preloadCacheDir: preloadCacheDir,logger: _logger,processManager: _processManager, pubCommand: _pubCommand);
-    // Use pub's default location by returning null.
+    if (preloadCacheDir.existsSync()) {
+      /// We only want to inform about existing caches on first run of a freshly
+      /// downloaded Flutter SDK. Therefore it is conditioned on the existence
+      /// of the .pub-preload-cache dir.
+      _informAboutExistingCaches();
+      final Iterable<String> cacheFiles =
+            preloadCacheDir
+              .listSync()
+              .map((FileSystemEntity f) => f.path)
+              .where((String path) => path.endsWith('.tar.gz'));
+      _processManager.runSync(<String>[..._pubCommand, 'cache', 'preload', ...cacheFiles]);
+      _tryDeleteDirectory(preloadCacheDir, _logger);
+    }
+  }
+
+  /// Issues a log message if there is an existing pub cache and or an existing
+  /// Dart Analysis Server cache.
+  void _informAboutExistingCaches() {
+    final String? pubCachePath = _pubCacheDefaultLocation();
+    if (pubCachePath != null) {
+      final Directory pubCacheDirectory = _fileSystem.directory(pubCachePath);
+      if (pubCacheDirectory.existsSync()) {
+        _logger.printStatus('''
+Found an existing Pub cache at $pubCachePath.
+It can be repaired by running `dart pub cache repair`.
+It can be reset by running `dart pub cache clear`.''');
+      }
+    }
+    final String? home = _platform.environment['HOME'];
+    if (home != null) {
+      final String dartServerCachePath = _fileSystem.path.join(home, '.dartServer');
+      if (_fileSystem.directory(dartServerCachePath).existsSync()) {
+        _logger.printStatus('''
+Found an existing Dart Analysis Server cache at $dartServerCachePath.
+It can be reset by deleting $dartServerCachePath.''');
+        }
+      }
+  }
+
+  /// The default location of the Pub cache if the PUB_CACHE environment variable
+  /// is not set.
+  ///
+  /// Returns null if the appropriate environment variables are unset.
+  String? _pubCacheDefaultLocation () {
+    if (_platform.isWindows) {
+      final String? localAppData = _platform.environment['LOCALAPPDATA'];
+      if (localAppData == null) {
         return null;
       }
+      return _fileSystem.path.join(localAppData, 'Pub', 'Cache');
+    } else {
+      final String? home = _platform.environment['HOME'];
+      if (home == null) {
+        return null;
+      }
+      return _fileSystem.path.join(home, '.pub-cache');
+    }
+  }
 
   /// The full environment used when running pub.
   ///

packages/flutter_tools/test/general.shard/dart/pub_get_test.dart

@@ -43,16 +43,23 @@ void main() {
       stdio: FakeStdio(),
     );
 
-    await expectLater(() => pub.get(
-      project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
+    await expectLater(
+        () => pub.get(
+              project:
+                  FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
               context: PubContext.pubGet,
               checkUpToDate: true,
-    ), throwsToolExit(message: 'Your Flutter SDK download may be corrupt or missing permissions to run'));
+            ),
+        throwsToolExit(
+            message:
+                'Your Flutter SDK download may be corrupt or missing permissions to run'));
   });
 
   group('shouldSkipThirdPartyGenerator', () {
-    testWithoutContext('does not skip pub get the parameter is false', () async {
-      final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    testWithoutContext('does not skip pub get the parameter is false',
+        () async {
+      final FakeProcessManager processManager =
+          FakeProcessManager.list(<FakeCommand>[
         const FakeCommand(command: <String>[
           'bin/cache/dart-sdk/bin/dart',
           'pub',
@@ -102,8 +109,11 @@ void main() {
       expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
     });
 
-    testWithoutContext('does not skip pub get if package_config.json has "generator": "pub"', () async {
-      final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    testWithoutContext(
+        'does not skip pub get if package_config.json has "generator": "pub"',
+        () async {
+      final FakeProcessManager processManager =
+          FakeProcessManager.list(<FakeCommand>[
         const FakeCommand(command: <String>[
           'bin/cache/dart-sdk/bin/dart',
           'pub',
@@ -153,8 +163,11 @@ void main() {
       expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
     });
 
-    testWithoutContext('does not skip pub get if package_config.json has "generator": "pub"', () async {
-      final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    testWithoutContext(
+        'does not skip pub get if package_config.json has "generator": "pub"',
+        () async {
+      final FakeProcessManager processManager =
+          FakeProcessManager.list(<FakeCommand>[
         const FakeCommand(command: <String>[
           'bin/cache/dart-sdk/bin/dart',
           'pub',
@@ -204,7 +217,8 @@ void main() {
       expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
     });
 
-    testWithoutContext('skips pub get if the package config "generator" is '
+    testWithoutContext(
+        'skips pub get if the package config "generator" is '
         'different than "pub"', () async {
       final FakeProcessManager processManager = FakeProcessManager.empty();
       final BufferLogger logger = BufferLogger.test();
@@ -239,15 +253,19 @@ void main() {
     });
   });
 
-  testWithoutContext('checkUpToDate skips pub get if the package config is newer than the pubspec '
-    'and the current framework version is the same as the last version', () async {
+  testWithoutContext(
+      'checkUpToDate skips pub get if the package config is newer than the pubspec '
+      'and the current framework version is the same as the last version',
+      () async {
     final FakeProcessManager processManager = FakeProcessManager.empty();
     final BufferLogger logger = BufferLogger.test();
     final MemoryFileSystem fileSystem = MemoryFileSystem.test();
 
     fileSystem.file('pubspec.yaml').createSync();
     fileSystem.file('pubspec.lock').createSync();
-    fileSystem.file('.dart_tool/package_config.json').createSync(recursive: true);
+    fileSystem
+        .file('.dart_tool/package_config.json')
+        .createSync(recursive: true);
     fileSystem.file('.dart_tool/version').writeAsStringSync('a');
     fileSystem.file('version').writeAsStringSync('a');
 
@@ -270,9 +288,12 @@ void main() {
     expect(logger.traceText, contains('Skipping pub get: version match.'));
   });
 
-  testWithoutContext('checkUpToDate does not skip pub get if the package config is newer than the pubspec '
-    'but the current framework version is not the same as the last version', () async {
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+  testWithoutContext(
+      'checkUpToDate does not skip pub get if the package config is newer than the pubspec '
+      'but the current framework version is not the same as the last version',
+      () async {
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(command: <String>[
         'bin/cache/dart-sdk/bin/dart',
         'pub',
@@ -288,7 +309,9 @@ void main() {
 
     fileSystem.file('pubspec.yaml').createSync();
     fileSystem.file('pubspec.lock').createSync();
-    fileSystem.file('.dart_tool/package_config.json').createSync(recursive: true);
+    fileSystem
+        .file('.dart_tool/package_config.json')
+        .createSync(recursive: true);
     fileSystem.file('.dart_tool/version').writeAsStringSync('a');
     fileSystem.file('version').writeAsStringSync('b');
 
@@ -312,9 +335,11 @@ void main() {
     expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
   });
 
-  testWithoutContext('checkUpToDate does not skip pub get if the package config is newer than the pubspec '
+  testWithoutContext(
+      'checkUpToDate does not skip pub get if the package config is newer than the pubspec '
       'but the current framework version does not exist yet', () async {
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(command: <String>[
         'bin/cache/dart-sdk/bin/dart',
         'pub',
@@ -330,7 +355,9 @@ void main() {
 
     fileSystem.file('pubspec.yaml').createSync();
     fileSystem.file('pubspec.lock').createSync();
-    fileSystem.file('.dart_tool/package_config.json').createSync(recursive: true);
+    fileSystem
+        .file('.dart_tool/package_config.json')
+        .createSync(recursive: true);
     fileSystem.file('version').writeAsStringSync('b');
 
     final Pub pub = Pub.test(
@@ -353,10 +380,14 @@ void main() {
     expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
   });
 
-  testWithoutContext('checkUpToDate does not skip pub get if the package config does not exist', () async {
+  testWithoutContext(
+      'checkUpToDate does not skip pub get if the package config does not exist',
+      () async {
     final MemoryFileSystem fileSystem = MemoryFileSystem.test();
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
-      FakeCommand(command: const <String>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
+      FakeCommand(
+          command: const <String>[
             'bin/cache/dart-sdk/bin/dart',
             'pub',
             '--suppress-analytics',
@@ -364,8 +395,11 @@ void main() {
             '.',
             'get',
             '--example',
-      ], onRun: () {
-        fileSystem.file('.dart_tool/package_config.json').createSync(recursive: true);
+          ],
+          onRun: () {
+            fileSystem
+                .file('.dart_tool/package_config.json')
+                .createSync(recursive: true);
           }),
     ]);
     final BufferLogger logger = BufferLogger.test();
@@ -394,9 +428,12 @@ void main() {
     expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
   });
 
-  testWithoutContext('checkUpToDate does not skip pub get if the pubspec.lock does not exist', () async {
+  testWithoutContext(
+      'checkUpToDate does not skip pub get if the pubspec.lock does not exist',
+      () async {
     final MemoryFileSystem fileSystem = MemoryFileSystem.test();
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(command: <String>[
         'bin/cache/dart-sdk/bin/dart',
         'pub',
@@ -411,7 +448,9 @@ void main() {
 
     fileSystem.file('pubspec.yaml').createSync();
     fileSystem.file('version').writeAsStringSync('b');
-    fileSystem.file('.dart_tool/package_config.json').createSync(recursive: true);
+    fileSystem
+        .file('.dart_tool/package_config.json')
+        .createSync(recursive: true);
     fileSystem.file('.dart_tool/version').writeAsStringSync('b');
 
     final Pub pub = Pub.test(
@@ -434,8 +473,11 @@ void main() {
     expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
   });
 
-  testWithoutContext('checkUpToDate does not skip pub get if the package config is older that the pubspec', () async {
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+  testWithoutContext(
+      'checkUpToDate does not skip pub get if the package config is older that the pubspec',
+      () async {
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(command: <String>[
         'bin/cache/dart-sdk/bin/dart',
         'pub',
@@ -476,8 +518,11 @@ void main() {
     expect(fileSystem.file('.dart_tool/version').readAsStringSync(), 'b');
   });
 
-  testWithoutContext('checkUpToDate does not skip pub get if the pubspec.lock is older that the pubspec', () async {
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+  testWithoutContext(
+      'checkUpToDate does not skip pub get if the pubspec.lock is older that the pubspec',
+      () async {
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(command: <String>[
         'bin/cache/dart-sdk/bin/dart',
         'pub',
@@ -495,7 +540,8 @@ void main() {
     fileSystem.file('pubspec.lock')
       ..createSync()
       ..setLastModifiedSync(DateTime(1991));
-    fileSystem.file('.dart_tool/package_config.json')
+    fileSystem
+        .file('.dart_tool/package_config.json')
         .createSync(recursive: true);
     fileSystem.file('version').writeAsStringSync('b');
     fileSystem.file('.dart_tool/version').writeAsStringSync('b');
@@ -524,7 +570,8 @@ void main() {
     final BufferLogger logger = BufferLogger.test();
     final FileSystem fileSystem = MemoryFileSystem.test();
 
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(
         command: <String>[
           'bin/cache/dart-sdk/bin/dart',
@@ -538,7 +585,10 @@ void main() {
         exitCode: 66,
         stderr: 'err1\nerr2\nerr3\n',
         stdout: 'out1\nout2\nout3\n',
-        environment: <String, String>{'FLUTTER_ROOT': '', 'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests'},
+        environment: <String, String>{
+          'FLUTTER_ROOT': '',
+          'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests'
+        },
       ),
     ]);
     final FakeStdio mockStdio = FakeStdio();
@@ -565,30 +615,27 @@ exit code: 66
         project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
         context: PubContext.flutterTests,
       ),
-      throwsA(isA<ToolExit>().having((ToolExit error) => error.message, 'message', null)),
+      throwsA(isA<ToolExit>()
+          .having((ToolExit error) => error.message, 'message', null)),
     );
     expect(logger.statusText, isEmpty);
     expect(logger.traceText, contains(toolExitMessage));
-    expect(
-      mockStdio.stdout.writes.map(utf8.decode),
-      <String>[
+    expect(mockStdio.stdout.writes.map(utf8.decode), <String>[
       'out1\nout2\nout3\n',
-      ]
-    );
-    expect(
-      mockStdio.stderr.writes.map(utf8.decode),
-      <String>[
+    ]);
+    expect(mockStdio.stderr.writes.map(utf8.decode), <String>[
       'err1\nerr2\nerr3\n',
-      ]
-    );
+    ]);
     expect(processManager, hasNoRemainingExpectations);
   });
 
-  testWithoutContext('pub get shows working directory on process exception', () async {
+  testWithoutContext('pub get shows working directory on process exception',
+      () async {
     final BufferLogger logger = BufferLogger.test();
     final FileSystem fileSystem = MemoryFileSystem.test();
 
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       FakeCommand(
         command: const <String>[
           'bin/cache/dart-sdk/bin/dart',
@@ -617,7 +664,10 @@ exit code: 66
         exitCode: 66,
         stderr: 'err1\nerr2\nerr3\n',
         stdout: 'out1\nout2\nout3\n',
-        environment: const <String, String>{'FLUTTER_ROOT': '', 'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests'},
+        environment: const <String, String>{
+          'FLUTTER_ROOT': '',
+          'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests'
+        },
       ),
     ]);
 
@@ -636,11 +686,13 @@ exit code: 66
         context: PubContext.flutterTests,
       ),
       throwsA(
-        isA<ProcessException>().having(
+        isA<ProcessException>()
+            .having(
               (ProcessException error) => error.message,
               'message',
               contains('Working directory: "/" (exists)'),
-        ).having(
+            )
+            .having(
               (ProcessException error) => error.message,
               'message',
               contains('"PUB_ENVIRONMENT": "flutter_cli:flutter_tests"'),
@@ -657,7 +709,8 @@ exit code: 66
     final BufferLogger logger = BufferLogger.test();
     final FileSystem fileSystem = MemoryFileSystem.test();
 
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(
         command: <String>[
           'bin/cache/dart-sdk/bin/dart',
@@ -670,7 +723,10 @@ exit code: 66
         ],
         stderr: 'err1\nerr2\nerr3\n',
         stdout: 'out1\nout2\nout3\n',
-        environment: <String, String>{'FLUTTER_ROOT': '', 'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests'},
+        environment: <String, String>{
+          'FLUTTER_ROOT': '',
+          'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests'
+        },
       ),
     ]);
 
@@ -697,18 +753,16 @@ exit code: 66
 
     expect(
         mockStdio.stdout.writes.map(utf8.decode),
-      isNot(
-        <String>[
+        isNot(<String>[
           'out1\nout2\nout3\n',
-        ]
-      )
-    );
+        ]));
     expect(processManager, hasNoRemainingExpectations);
   });
 
   testWithoutContext('pub cache in flutter root is ignored', () async {
     final FileSystem fileSystem = MemoryFileSystem.test();
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(
           command: <String>[
             'bin/cache/dart-sdk/bin/dart',
@@ -724,8 +778,7 @@ exit code: 66
             'FLUTTER_ROOT': '',
             'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests',
           },
-        stdout: "FakeCommand's env successfully matched"
-      ),
+          stdout: "FakeCommand's env successfully matched"),
     ]);
 
     final FakeStdio mockStdio = FakeStdio();
@@ -741,29 +794,29 @@ exit code: 66
 
     try {
       await pub.get(
-        project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
-        context: PubContext.flutterTests
-      );
+          project:
+              FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
+          context: PubContext.flutterTests);
     } on ToolExit {
       // Ignore.
     }
 
-    expect(
-      mockStdio.stdout.writes.map(utf8.decode),
-      <String>[
+    expect(mockStdio.stdout.writes.map(utf8.decode), <String>[
       "FakeCommand's env successfully matched",
-      ]
-    );
+    ]);
     expect(processManager, hasNoRemainingExpectations);
   });
 
   testWithoutContext('Preloaded packages are added to the pub cache', () async {
     final FileSystem fileSystem = MemoryFileSystem.test();
-    final Directory preloadCache = fileSystem.currentDirectory.childDirectory('.pub-preload-cache');
+    final Directory preloadCache =
+        fileSystem.currentDirectory.childDirectory('.pub-preload-cache');
     preloadCache.childFile('a.tar.gz').createSync(recursive: true);
     preloadCache.childFile('b.tar.gz').createSync();
+    fileSystem.currentDirectory.childFile('version').createSync();
 
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(
         command: <String>[
           'bin/cache/dart-sdk/bin/dart',
@@ -775,8 +828,8 @@ exit code: 66
           '.pub-preload-cache/b.tar.gz',
         ],
       ),
-      const FakeCommand(
-        command: <String>[
+      FakeCommand(
+          command: const <String>[
             'bin/cache/dart-sdk/bin/dart',
             'pub',
             '--suppress-analytics',
@@ -785,44 +838,129 @@ exit code: 66
             'get',
             '--example',
           ],
-        exitCode: 69,
-        environment: <String, String>{
+          environment: const <String, String>{
             'FLUTTER_ROOT': '',
             'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests',
           },
-      ),
+          onRun: () {
+            fileSystem.currentDirectory
+                .childDirectory('.dart_tool')
+                .childFile('package_config.json')
+                .createSync(recursive: true);
+          }),
     ]);
 
-    final Platform platform = FakePlatform(
-      environment: <String, String>{'HOME': '/global'}
-    );
+    final Platform platform =
+        FakePlatform(environment: <String, String>{'HOME': '/global'});
+    final BufferLogger logger = BufferLogger.test();
     final Pub pub = Pub.test(
       platform: platform,
       usage: TestUsage(),
       fileSystem: fileSystem,
-      logger: BufferLogger.test(),
+      logger: logger,
       processManager: processManager,
       botDetector: const BotDetectorAlwaysNo(),
       stdio: FakeStdio(),
     );
 
-    try {
     await pub.get(
         project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
-        context: PubContext.flutterTests
-      );
-    } on ToolExit {
-      // Ignore.
-    }
+        context: PubContext.flutterTests);
+    expect(logger.statusText, isNot(contains('Found an existing Pub cache')));
+    expect(logger.statusText,
+        isNot(contains('Found an existing Dart Analysis Server cache')));
 
     expect(processManager, hasNoRemainingExpectations);
     expect(preloadCache.existsSync(), false);
   });
 
+  testWithoutContext('Notifies about existing caches, on first run only',
+      () async {
+    final FileSystem fileSystem = MemoryFileSystem.test();
+    final Directory preloadCache =
+        fileSystem.currentDirectory.childDirectory('.pub-preload-cache');
+    preloadCache.childFile('a.tar.gz').createSync(recursive: true);
+    fileSystem.currentDirectory.childFile('version').createSync();
+    fileSystem.directory('/global/.pub-cache').createSync(recursive: true);
+    fileSystem.directory('/global/.dartServer').createSync(recursive: true);
+
+    const FakeCommand dartPreloadCommand = FakeCommand(
+      command: <String>[
+        'bin/cache/dart-sdk/bin/dart',
+        'pub',
+        '--suppress-analytics',
+        'cache',
+        'preload',
+        '.pub-preload-cache/a.tar.gz',
+      ],
+    );
+    final FakeCommand dartPubGetCommand = FakeCommand(
+        command: const <String>[
+          'bin/cache/dart-sdk/bin/dart',
+          'pub',
+          '--suppress-analytics',
+          '--directory',
+          '.',
+          'get',
+          '--example',
+        ],
+        environment: const <String, String>{
+          'FLUTTER_ROOT': '',
+          'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests',
+        },
+        onRun: () {
+          fileSystem.currentDirectory
+              .childDirectory('.dart_tool')
+              .childFile('package_config.json')
+              .createSync(recursive: true);
+        });
+
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
+      dartPreloadCommand,
+      dartPubGetCommand,
+      dartPubGetCommand,
+    ]);
+
+    final Platform platform =
+        FakePlatform(environment: <String, String>{'HOME': '/global'});
+    final BufferLogger logger = BufferLogger.test();
+    final Pub pub = Pub.test(
+      platform: platform,
+      usage: TestUsage(),
+      fileSystem: fileSystem,
+      logger: logger,
+      processManager: processManager,
+      botDetector: const BotDetectorAlwaysNo(),
+      stdio: FakeStdio(),
+    );
+
+    await pub.get(
+        project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
+        context: PubContext.flutterTests);
+    expect(logger.statusText,
+        contains('Found an existing Pub cache at /global/.pub-cache'));
+    expect(
+      logger.statusText,
+      contains(
+          'Found an existing Dart Analysis Server cache at /global/.dartServer'),
+    );
+    expect(preloadCache.existsSync(), false);
+    logger.clear();
+    await pub.get(
+        project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
+        context: PubContext.flutterTests);
+    expect(logger.statusText, isNot(contains('Found an existing Pub cache')));
+    expect(logger.statusText,
+        isNot(contains('Found an existing Dart Analysis Server cache')));
+    expect(processManager, hasNoRemainingExpectations);
+  });
+
   testWithoutContext('pub cache in environment is used', () async {
     final FileSystem fileSystem = MemoryFileSystem.test();
     fileSystem.directory('custom/pub-cache/path').createSync(recursive: true);
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(
           command: <String>[
             'bin/cache/dart-sdk/bin/dart',
@@ -839,8 +977,7 @@ exit code: 66
             'PUB_ENVIRONMENT': 'flutter_cli:flutter_tests',
             'PUB_CACHE': 'custom/pub-cache/path',
           },
-        stdout: "FakeCommand's env successfully matched"
-      ),
+          stdout: "FakeCommand's env successfully matched"),
     ]);
 
     final FakeStdio mockStdio = FakeStdio();
@@ -860,19 +997,16 @@ exit code: 66
 
     try {
       await pub.get(
-        project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
-        context: PubContext.flutterTests
-      );
+          project:
+              FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
+          context: PubContext.flutterTests);
     } on ToolExit {
       // Ignore.
     }
 
-    expect(
-      mockStdio.stdout.writes.map(utf8.decode),
-      <String>[
+    expect(mockStdio.stdout.writes.map(utf8.decode), <String>[
       "FakeCommand's env successfully matched",
-      ]
-    );
+    ]);
     expect(processManager, hasNoRemainingExpectations);
   });
 
@@ -886,11 +1020,9 @@ exit code: 66
       botDetector: const BotDetectorAlwaysNo(),
       stdio: FakeStdio(),
       usage: usage,
-      platform: FakePlatform(
-        environment: const <String, String>{
+      platform: FakePlatform(environment: const <String, String>{
         'PUB_CACHE': 'custom/pub-cache/path',
-        }
-      ),
+      }),
     );
     fileSystem.file('version').createSync();
     fileSystem.file('pubspec.yaml').createSync();
@@ -902,12 +1034,16 @@ exit code: 66
       project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
       context: PubContext.flutterTests,
     );
-    expect(usage.events, contains(
+    expect(
+        usage.events,
+        contains(
           const TestUsageEvent('pub-result', 'flutter-tests', label: 'success'),
         ));
   });
 
-  testWithoutContext('package_config_subset file is generated from packages and not timestamp', () async {
+  testWithoutContext(
+      'package_config_subset file is generated from packages and not timestamp',
+      () async {
     final FileSystem fileSystem = MemoryFileSystem.test();
     final TestUsage usage = TestUsage();
     final Pub pub = Pub.test(
@@ -917,11 +1053,9 @@ exit code: 66
       botDetector: const BotDetectorAlwaysNo(),
       stdio: FakeStdio(),
       usage: usage,
-      platform: FakePlatform(
-        environment: const <String, String>{
+      platform: FakePlatform(environment: const <String, String>{
         'PUB_CACHE': 'custom/pub-cache/path',
-        }
-      ),
+      }),
     );
     fileSystem.file('version').createSync();
     fileSystem.file('pubspec.yaml').createSync();
@@ -958,7 +1092,8 @@ exit code: 66
     fileSystem.directory('custom/pub-cache/path').createSync(recursive: true);
     final TestUsage usage = TestUsage();
 
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       const FakeCommand(
         command: <String>[
           'bin/cache/dart-sdk/bin/dart',
@@ -995,7 +1130,9 @@ exit code: 66
       // Ignore.
     }
 
-    expect(usage.events, contains(
+    expect(
+        usage.events,
+        contains(
           const TestUsageEvent('pub-result', 'flutter-tests', label: 'failure'),
         ));
     expect(processManager, hasNoRemainingExpectations);
@@ -1004,7 +1141,8 @@ exit code: 66
   testWithoutContext('Pub error handling', () async {
     final BufferLogger logger = BufferLogger.test();
     final MemoryFileSystem fileSystem = MemoryFileSystem.test();
-    final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+    final FakeProcessManager processManager =
+        FakeProcessManager.list(<FakeCommand>[
       FakeCommand(
           command: const <String>[
             'bin/cache/dart-sdk/bin/dart',
@@ -1016,10 +1154,10 @@ exit code: 66
             '--example',
           ],
           onRun: () {
-          fileSystem.file('.dart_tool/package_config.json')
+            fileSystem
+                .file('.dart_tool/package_config.json')
                 .setLastModifiedSync(DateTime(2002));
-        }
-      ),
+          }),
       const FakeCommand(
         command: <String>[
           'bin/cache/dart-sdk/bin/dart',
@@ -1042,10 +1180,8 @@ exit code: 66
             '--example',
           ],
           onRun: () {
-          fileSystem.file('pubspec.yaml')
-            .setLastModifiedSync(DateTime(2002));
-        }
-      ),
+            fileSystem.file('pubspec.yaml').setLastModifiedSync(DateTime(2002));
+          }),
       const FakeCommand(
         command: <String>[
           'bin/cache/dart-sdk/bin/dart',
@@ -1067,8 +1203,7 @@ exit code: 66
           environment: <String, String>{},
         ),
         botDetector: const BotDetectorAlwaysNo(),
-      stdio: FakeStdio()
-    );
+        stdio: FakeStdio());
 
     fileSystem.file('version').createSync();
     // the good scenario: .packages is old, pub updates the file.
@@ -1084,14 +1219,15 @@ exit code: 66
     ); // pub sets date of .packages to 2002
 
     expect(logger.errorText, isEmpty);
-    expect(fileSystem.file('pubspec.yaml').lastModifiedSync(), DateTime(2001)); // because nothing should touch it
+    expect(fileSystem.file('pubspec.yaml').lastModifiedSync(),
+        DateTime(2001)); // because nothing should touch it
     logger.clear();
 
     // bad scenario 1: pub doesn't update file; doesn't matter, because we do instead
-    fileSystem.file('.dart_tool/package_config.json')
+    fileSystem
+        .file('.dart_tool/package_config.json')
         .setLastModifiedSync(DateTime(2000));
-    fileSystem.file('pubspec.yaml')
-      .setLastModifiedSync(DateTime(2001));
+    fileSystem.file('pubspec.yaml').setLastModifiedSync(DateTime(2001));
     await pub.get(
       project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
       context: PubContext.flutterTests,
@@ -1099,7 +1235,8 @@ exit code: 66
 
     expect(logger.statusText, isEmpty);
     expect(logger.errorText, isEmpty);
-    expect(fileSystem.file('pubspec.yaml').lastModifiedSync(), DateTime(2001)); // because nothing should touch it
+    expect(fileSystem.file('pubspec.yaml').lastModifiedSync(),
+        DateTime(2001)); // because nothing should touch it
     logger.clear();
   });
 }