[flutter_tools] shrink fingerprinter API to currently used subset (#63840)

packages/flutter_tools/lib/src/base/fingerprint.dart

@@ -6,59 +6,46 @@ import 'package:crypto/crypto.dart' show md5;
 import 'package:meta/meta.dart';
 
 import '../convert.dart' show json;
-import '../globals.dart' as globals;
 import 'file_system.dart';
+import 'logger.dart';
 import 'utils.dart';
 
-typedef FingerprintPathFilter = bool Function(String path);
-
 /// A tool that can be used to compute, compare, and write [Fingerprint]s for a
 /// set of input files and associated build settings.
 ///
-/// This class can be used during build actions to compute a fingerprint of the
-/// build action inputs and options, and if unchanged from the previous build,
-/// skip the build step. This assumes that build outputs are strictly a product
-/// of the fingerprint inputs.
+/// This class should only be used in situations where `assemble` is not appropriate,
+/// such as checking if Cocoapods should be run.
 class Fingerprinter {
   Fingerprinter({
     @required this.fingerprintPath,
     @required Iterable<String> paths,
-    @required Map<String, String> properties,
-    Iterable<String> depfilePaths = const <String>[],
-    FingerprintPathFilter pathFilter,
+    @required FileSystem fileSystem,
+    @required Logger logger,
   }) : _paths = paths.toList(),
-       _properties = Map<String, String>.of(properties),
-       _depfilePaths = depfilePaths.toList(),
-       _pathFilter = pathFilter,
        assert(fingerprintPath != null),
        assert(paths != null && paths.every((String path) => path != null)),
-       assert(properties != null),
-       assert(depfilePaths != null && depfilePaths.every((String path) => path != null));
+       _logger = logger,
+       _fileSystem = fileSystem;
 
   final String fingerprintPath;
   final List<String> _paths;
-  final Map<String, String> _properties;
-  final List<String> _depfilePaths;
-  final FingerprintPathFilter _pathFilter;
+  final Logger _logger;
+  final FileSystem _fileSystem;
 
   Fingerprint buildFingerprint() {
     final List<String> paths = _getPaths();
-    return Fingerprint.fromBuildInputs(_properties, paths);
+    return Fingerprint.fromBuildInputs(paths, _fileSystem);
   }
 
   bool doesFingerprintMatch() {
     try {
-      final File fingerprintFile = globals.fs.file(fingerprintPath);
+      final File fingerprintFile = _fileSystem.file(fingerprintPath);
       if (!fingerprintFile.existsSync()) {
         return false;
       }
 
-      if (!_depfilePaths.every(globals.fs.isFileSync)) {
-        return false;
-      }
-
       final List<String> paths = _getPaths();
-      if (!paths.every(globals.fs.isFileSync)) {
+      if (!paths.every(_fileSystem.isFileSync)) {
         return false;
       }
 
@@ -67,7 +54,7 @@ class Fingerprinter {
       return oldFingerprint == newFingerprint;
     } on Exception catch (e) {
       // Log exception and continue, fingerprinting is only a performance improvement.
-      globals.printTrace('Fingerprint check error: $e');
+      _logger.printTrace('Fingerprint check error: $e');
     }
     return false;
   }
@@ -75,22 +62,14 @@ class Fingerprinter {
   void writeFingerprint() {
     try {
       final Fingerprint fingerprint = buildFingerprint();
-      globals.fs.file(fingerprintPath).writeAsStringSync(fingerprint.toJson());
+      _fileSystem.file(fingerprintPath).writeAsStringSync(fingerprint.toJson());
     } on Exception catch (e) {
       // Log exception and continue, fingerprinting is only a performance improvement.
-      globals.printTrace('Fingerprint write error: $e');
+      _logger.printTrace('Fingerprint write error: $e');
     }
   }
 
-  List<String> _getPaths() {
-    final Set<String> paths = <String>{
-      ..._paths,
-      for (final String depfilePath in _depfilePaths)
-        ...readDepfile(depfilePath),
-    };
-    final FingerprintPathFilter filter = _pathFilter ?? (String path) => true;
-    return paths.where(filter).toList()..sort();
-  }
+  List<String> _getPaths() => _paths;
 }
 
 /// A fingerprint that uniquely identifies a set of build input files and
@@ -101,23 +80,19 @@ class Fingerprinter {
 class Fingerprint {
   const Fingerprint._({
     Map<String, String> checksums,
-    Map<String, String> properties,
-  })  : _checksums = checksums,
-        _properties = properties;
+  })  : _checksums = checksums;
 
-  factory Fingerprint.fromBuildInputs(Map<String, String> properties, Iterable<String> inputPaths) {
-    final Iterable<File> files = inputPaths.map<File>(globals.fs.file);
+  factory Fingerprint.fromBuildInputs(Iterable<String> inputPaths, FileSystem fileSystem) {
+    final Iterable<File> files = inputPaths.map<File>(fileSystem.file);
     final Iterable<File> missingInputs = files.where((File file) => !file.existsSync());
     if (missingInputs.isNotEmpty) {
       throw Exception('Missing input files:\n' + missingInputs.join('\n'));
     }
     return Fingerprint._(
-      // ignore: prefer_const_literals_to_create_immutables, https://github.com/dart-lang/linter/issues/2025
       checksums: <String, String>{
         for (final File file in files)
           file.path: md5.convert(file.readAsBytesSync()).toString(),
       },
-      properties: <String, String>{...properties},
     );
   }
 
@@ -127,37 +102,21 @@ class Fingerprint {
   /// serializing framework and this framework.
   factory Fingerprint.fromJson(String jsonData) {
     final Map<String, dynamic> content = castStringKeyedMap(json.decode(jsonData));
-
-    final String version = content['version'] as String;
-    if (version != globals.flutterVersion.frameworkRevision) {
-      throw Exception('Incompatible fingerprint version: $version');
-    }
     return Fingerprint._(
       checksums: castStringKeyedMap(content['files'])?.cast<String,String>() ?? <String, String>{},
-      properties: castStringKeyedMap(content['properties'])?.cast<String,String>() ?? <String, String>{},
     );
   }
 
   final Map<String, String> _checksums;
-  final Map<String, String> _properties;
 
   String toJson() => json.encode(<String, dynamic>{
-    'version': globals.flutterVersion.frameworkRevision,
-    'properties': _properties,
     'files': _checksums,
   });
 
   @override
   bool operator==(Object other) {
-    if (identical(other, this)) {
-      return true;
-    }
-    if (other.runtimeType != runtimeType) {
-      return false;
-    }
     return other is Fingerprint
-        && _equalMaps(other._checksums, _checksums)
-        && _equalMaps(other._properties, _properties);
+        && _equalMaps(other._checksums, _checksums);
   }
 
   bool _equalMaps(Map<String, String> a, Map<String, String> b) {
@@ -169,37 +128,8 @@ class Fingerprint {
   // Ignore map entries here to avoid becoming inconsistent with equals
   // due to differences in map entry order. This is a really bad hash
   // function and should eventually be deprecated and removed.
-  int get hashCode => _properties.length + _checksums.length;
+  int get hashCode => _checksums.length.hashCode;
 
   @override
-  String toString() => '{checksums: $_checksums, properties: $_properties}';
-}
-
-final RegExp _separatorExpr = RegExp(r'([^\\]) ');
-final RegExp _escapeExpr = RegExp(r'\\(.)');
-
-/// Parses a VM snapshot dependency file.
-///
-/// Snapshot dependency files are a single line mapping the output snapshot to a
-/// space-separated list of input files used to generate that output. Spaces and
-/// backslashes are escaped with a backslash. For example:
-///
-///     outfile : file1.dart fil\\e2.dart fil\ e3.dart
-///
-/// will return a set containing: 'file1.dart', 'fil\e2.dart', 'fil e3.dart'.
-Set<String> readDepfile(String depfilePath) {
-  // Depfile format:
-  // outfile1 outfile2 : file1.dart file2.dart file3.dart
-  final String contents = globals.fs.file(depfilePath).readAsStringSync();
-
-  final List<String> dependencies = contents.split(': ');
-  if (dependencies.length < 2) {
-    throw Exception('malformed depfile');
-  }
-  return dependencies[1]
-      .replaceAllMapped(_separatorExpr, (Match match) => '${match.group(1)}\n')
-      .split('\n')
-      .map<String>((String path) => path.replaceAllMapped(_escapeExpr, (Match match) => match.group(1)).trim())
-      .where((String path) => path.isNotEmpty)
-      .toSet();
+  String toString() => '{checksums: $_checksums}';
 }

packages/flutter_tools/lib/src/macos/cocoapod_utils.dart

@@ -13,7 +13,11 @@ import '../project.dart';
 
 /// For a given build, determines whether dependencies have changed since the
 /// last call to processPods, then calls processPods with that information.
-Future<void> processPodsIfNeeded(XcodeBasedProject xcodeProject, String buildDirectory, BuildMode buildMode) async {
+Future<void> processPodsIfNeeded(
+  XcodeBasedProject xcodeProject,
+  String buildDirectory,
+  BuildMode buildMode,
+) async {
   final FlutterProject project = xcodeProject.parent;
   // Ensure that the plugin list is up to date, since hasPlugins relies on it.
   await refreshPluginsList(project);
@@ -29,7 +33,8 @@ Future<void> processPodsIfNeeded(XcodeBasedProject xcodeProject, String buildDir
       xcodeProject.podfile.path,
       xcodeProject.generatedXcodePropertiesFile.path,
     ],
-    properties: <String, String>{},
+    fileSystem: globals.fs,
+    logger: globals.logger,
   );
 
   final bool didPodInstall = await globals.cocoaPods.processPods(