Update typedef syntax to use Function notation and turn on lint for old notation. (#18362)

Now that Dart 1 is turned off, reapplying my change to turn on the prefer_generic_function_type_aliases analysis option, and fix all the typedefs to Dart 2 preferred syntax.

Also eliminated the unused analysis_options_repo.yaml file and turned on public_member_api_docs in analysys_options.yaml.

No logic changes, just changing the typedef syntax for all typedefs, and updating analysis options.

analysis_options.yaml

@@ -7,17 +7,17 @@
 # See the configuration guide for more
 # https://github.com/dart-lang/sdk/tree/master/pkg/analyzer#configuring-the-analyzer
 #
-# There are four similar analysis options files in the flutter repos:
+# There are four similar analysis options files in the flutter repo:
 #   - analysis_options.yaml (this file)
 #   - packages/flutter/lib/analysis_options_user.yaml
 #   - https://github.com/flutter/plugins/blob/master/analysis_options.yaml
 #   - https://github.com/flutter/engine/blob/master/analysis_options.yaml
 #
-# This file contains the analysis options used by Flutter tools, such as IntelliJ,
-# Android Studio, and the `flutter analyze` command.
+# This file contains the analysis options used by Flutter tools, such as
+# IntelliJ, Android Studio, and the 'flutter analyze' command.
 #
-# The flutter/plugins repo contains a copy of this file, which should be kept
-# in sync with this file.
+# The flutter/plugins and flutter/engine repos contain a copy of this file,
+# which should be kept in sync with this file.
 
 analyzer:
   language:
@@ -124,6 +124,7 @@ linter:
     - prefer_final_locals
     - prefer_foreach
     # - prefer_function_declarations_over_variables # not yet tested
+    - prefer_generic_function_type_aliases
     - prefer_initializing_formals
     # - prefer_interpolation_to_compose_strings # not yet tested
     # - prefer_iterable_whereType # https://github.com/dart-lang/sdk/issues/32463
@@ -131,6 +132,7 @@ linter:
     - prefer_is_not_empty
     - prefer_single_quotes
     - prefer_typing_uninitialized_variables
+    - public_member_api_docs
     - recursive_getters
     - slash_for_doc_comments
     - sort_constructors_first

analysis_options_repo.yaml

@@ -1,157 +0,0 @@
-# Specify analysis options.
-#
-# Until there are meta linter rules, each desired lint must be explicitly enabled.
-# See: https://github.com/dart-lang/linter/issues/288
-#
-# For a list of lints, see: http://dart-lang.github.io/linter/lints/
-# See the configuration guide for more
-# https://github.com/dart-lang/sdk/tree/master/pkg/analyzer#configuring-the-analyzer
-#
-# There are three similar analysis options files in the flutter repo:
-#   - analysis_options.yaml
-#   - analysis_options_repo.yaml (this file)
-#   - packages/flutter/lib/analysis_options_user.yaml
-#
-# This file contains the analysis options used by 'flutter analyze' when analyzing
-# the flutter repository. It is very similar to analysis_options.yaml;
-# the only difference (currently) is the public_member_api_docs option,
-# which is turned on and programmatically reduced to a single output line
-# indicating the # of violations for that rule.
-
-analyzer:
-  language:
-    enableStrictCallChecks: true
-    enableSuperMixins: true
-  strong-mode:
-    implicit-dynamic: false
-  errors:
-    # treat missing required parameters as a warning (not a hint)
-    missing_required_param: warning
-    # treat missing returns as a warning (not a hint)
-    missing_return: warning
-    # allow having TODOs in the code
-    todo: ignore
-  # `flutter analyze` (without `--watch`) just ignores directories
-  # that contain a .dartignore file, and this file does not have any
-  # effect on what files are actually analyzed.
-
-linter:
-  rules:
-    # these rules are documented on and in the same order as
-    # the Dart Lint rules page to make maintenance easier
-    # https://github.com/dart-lang/linter/blob/master/example/all.yaml
-    - always_declare_return_types
-    - always_put_control_body_on_new_line
-    # - always_put_required_named_parameters_first # we prefer having parameters in the same order as fields https://github.com/flutter/flutter/issues/10219
-    - always_require_non_null_named_parameters
-    - always_specify_types
-    - annotate_overrides
-    # - avoid_annotating_with_dynamic # conflicts with always_specify_types
-    - avoid_as
-    # - avoid_bool_literals_in_conditional_expressions # not yet tested
-    # - avoid_catches_without_on_clauses # we do this commonly
-    # - avoid_catching_errors # we do this commonly
-    - avoid_classes_with_only_static_members
-    # - avoid_double_and_int_checks # only useful when targeting JS runtime
-    - avoid_empty_else
-    # - avoid_field_initializers_in_const_classes # not yet tested
-    - avoid_function_literals_in_foreach_calls
-    - avoid_init_to_null
-    # - avoid_js_rounded_ints # only useful when targeting JS runtime
-    - avoid_null_checks_in_equality_operators
-    # - avoid_positional_boolean_parameters # not yet tested
-    # - avoid_private_typedef_functions # we prefer having typedef (discussion in https://github.com/flutter/flutter/pull/16356)
-    - avoid_relative_lib_imports
-    - avoid_renaming_method_parameters
-    - avoid_return_types_on_setters
-    # - avoid_returning_null # we do this commonly
-    # - avoid_returning_this # https://github.com/dart-lang/linter/issues/842
-    # - avoid_setters_without_getters # not yet tested
-    # - avoid_single_cascade_in_expression_statements # not yet tested
-    - avoid_slow_async_io
-    # - avoid_types_as_parameter_names # https://github.com/dart-lang/linter/pull/954/files
-    # - avoid_types_on_closure_parameters # conflicts with always_specify_types
-    # - avoid_unused_constructor_parameters # https://github.com/dart-lang/linter/pull/847
-    - await_only_futures
-    - camel_case_types
-    - cancel_subscriptions
-    # - cascade_invocations # not yet tested
-    # - close_sinks # https://github.com/flutter/flutter/issues/5789
-    # - comment_references # blocked on https://github.com/dart-lang/dartdoc/issues/1153
-    # - constant_identifier_names # https://github.com/dart-lang/linter/issues/204
-    - control_flow_in_finally
-    - directives_ordering
-    - empty_catches
-    - empty_constructor_bodies
-    - empty_statements
-    - hash_and_equals
-    - implementation_imports
-    # - invariant_booleans # https://github.com/flutter/flutter/issues/5790
-    - iterable_contains_unrelated_type
-    # - join_return_with_assignment # not yet tested
-    - library_names
-    - library_prefixes
-    - list_remove_unrelated_type
-    # - literal_only_boolean_expressions # https://github.com/flutter/flutter/issues/5791
-    - no_adjacent_strings_in_list
-    - no_duplicate_case_values
-    - non_constant_identifier_names
-    # - omit_local_variable_types # opposite of always_specify_types
-    # - one_member_abstracts # too many false positives
-    # - only_throw_errors # https://github.com/flutter/flutter/issues/5792
-    - overridden_fields
-    - package_api_docs
-    - package_names
-    - package_prefixed_library_names
-    # - parameter_assignments # we do this commonly
-    - prefer_adjacent_string_concatenation
-    - prefer_asserts_in_initializer_lists
-    - prefer_bool_in_asserts
-    - prefer_collection_literals
-    - prefer_conditional_assignment
-    - prefer_const_constructors
-    - prefer_const_constructors_in_immutables
-    - prefer_const_declarations
-    - prefer_const_literals_to_create_immutables
-    # - prefer_constructors_over_static_methods # not yet tested
-    - prefer_contains
-    - prefer_equal_for_default_values
-    # - prefer_expression_function_bodies # conflicts with https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo#consider-using--for-short-functions-and-methods
-    - prefer_final_fields
-    - prefer_final_locals
-    - prefer_foreach
-    # - prefer_function_declarations_over_variables # not yet tested
-    - prefer_initializing_formals
-    # - prefer_interpolation_to_compose_strings # not yet tested
-    # - prefer_iterable_whereType # https://github.com/dart-lang/sdk/issues/32463
-    - prefer_is_empty
-    - prefer_is_not_empty
-    - prefer_single_quotes
-    - prefer_typing_uninitialized_variables
-    - public_member_api_docs # this is the only difference from analysis_options.yaml
-    - recursive_getters
-    - slash_for_doc_comments
-    - sort_constructors_first
-    - sort_unnamed_constructors_first
-    - super_goes_last
-    - test_types_in_equals
-    - throw_in_finally
-    # - type_annotate_public_apis # subset of always_specify_types
-    - type_init_formals
-    # - unawaited_futures # https://github.com/flutter/flutter/issues/5793
-    - unnecessary_brace_in_string_interps
-    - unnecessary_getters_setters
-    # - unnecessary_lambdas # https://github.com/dart-lang/linter/issues/498
-    - unnecessary_null_aware_assignments
-    - unnecessary_null_in_if_null_operators
-    - unnecessary_overrides
-    - unnecessary_parenthesis
-    # - unnecessary_statements # not yet tested
-    - unnecessary_this
-    - unrelated_type_equality_checks
-    - use_rethrow_when_possible
-    # - use_setters_to_change_properties # not yet tested
-    # - use_string_buffers # https://github.com/dart-lang/linter/pull/664
-    # - use_to_and_as_if_applicable # has false positives, so we prefer to catch this by code-review
-    - valid_regexps
-    # - void_checks # not yet tested

dev/bots/prepare_package.dart

@@ -175,7 +175,7 @@ class ProcessRunner {
   }
 }
 
-typedef Future<Uint8List> HttpReader(Uri url, {Map<String, String> headers});
+typedef HttpReader = Future<Uint8List> Function(Uri url, {Map<String, String> headers});
 
 /// Creates a pre-populated Flutter archive from a git repo.
 class ArchiveCreator {

dev/bots/test.dart

@@ -8,7 +8,7 @@ import 'dart:io';
 
 import 'package:path/path.dart' as path;
 
-typedef Future<Null> ShardRunner();
+typedef ShardRunner = Future<Null> Function();
 
 final String flutterRoot = path.dirname(path.dirname(path.dirname(path.fromUri(Platform.script))));
 final String flutter = path.join(flutterRoot, 'bin', Platform.isWindows ? 'flutter.bat' : 'flutter');

dev/bots/test/fake_process_manager.dart

@@ -150,7 +150,7 @@ class FakeProcess extends Mock implements Process {
 }
 
 /// Callback used to receive stdin input when it occurs.
-typedef void StringReceivedCallback(String received);
+typedef StringReceivedCallback = void Function(String received);
 
 /// A stream consumer class that consumes UTF8 strings as lists of ints.
 class StringStreamConsumer implements StreamConsumer<List<int>> {

dev/devicelab/lib/framework/framework.dart

@@ -20,7 +20,7 @@ const Duration _kDefaultTaskTimeout = const Duration(minutes: 15);
 
 /// Represents a unit of work performed in the CI environment that can
 /// succeed, fail and be retried independently of others.
-typedef Future<TaskResult> TaskFunction();
+typedef TaskFunction = Future<TaskResult> Function();
 
 bool _isTaskRegistered = false;
 

dev/devicelab/lib/tasks/analysis.dart

@@ -15,7 +15,7 @@ const int _kRunsPerBenchmark = 3;
 
 /// Runs a benchmark once and reports the result as a lower-is-better numeric
 /// value.
-typedef Future<double> _Benchmark();
+typedef _Benchmark = Future<double> Function();
 
 /// Path to the generated "mega gallery" app.
 Directory get _megaGalleryDirectory => dir(path.join(Directory.systemTemp.path, 'mega_gallery'));

dev/devicelab/test/adb_test.dart

@@ -112,7 +112,7 @@ CommandArgs cmd({
   );
 }
 
-typedef dynamic ExitErrorFactory();
+typedef ExitErrorFactory = dynamic Function();
 
 class CommandArgs {
   CommandArgs({ this.command, this.arguments, this.environment });

dev/integration_tests/channels/lib/src/test_step.dart

@@ -11,7 +11,7 @@ import 'pair.dart';
 
 enum TestStatus { ok, pending, failed, complete }
 
-typedef Future<TestStepResult> TestStep();
+typedef TestStep = Future<TestStepResult> Function();
 
 const String nothing = '-';
 

dev/integration_tests/platform_interaction/lib/src/test_step.dart

@@ -8,7 +8,7 @@ import 'package:flutter/material.dart';
 
 enum TestStatus { ok, pending, failed, complete }
 
-typedef Future<TestStepResult> TestStep();
+typedef TestStep = Future<TestStepResult> Function();
 
 const String nothing = '-';
 

dev/manual_tests/lib/material_arc.dart

@@ -396,7 +396,7 @@ class _RectangleDemoState extends State<_RectangleDemo> {
   }
 }
 
-typedef Widget _DemoBuilder(_ArcDemo demo);
+typedef _DemoBuilder = Widget Function(_ArcDemo demo);
 
 class _ArcDemo {
   _ArcDemo(this.title, this.builder, TickerProvider vsync)

dev/manual_tests/lib/overlay_geometry.dart

@@ -92,7 +92,7 @@ class OverlayGeometryApp extends StatefulWidget {
   OverlayGeometryAppState createState() => new OverlayGeometryAppState();
 }
 
-typedef void CardTapCallback(GlobalKey targetKey, Offset globalPosition);
+typedef CardTapCallback = void Function(GlobalKey targetKey, Offset globalPosition);
 
 class CardBuilder extends SliverChildDelegate {
   CardBuilder({ this.cardModels, this.onTapUp });

examples/flutter_gallery/lib/demo/material/expansion_panels_demo.dart

@@ -10,8 +10,8 @@ enum _Location {
   Bermuda
 }
 
-typedef Widget DemoItemBodyBuilder<T>(DemoItem<T> item);
-typedef String ValueToString<T>(T value);
+typedef DemoItemBodyBuilder<T> = Widget Function(DemoItem<T> item);
+typedef ValueToString<T> = String Function(T value);
 
 class DualHeaderWithHint extends StatelessWidget {
   const DualHeaderWithHint({

examples/flutter_gallery/lib/demo/material/grid_list_demo.dart

@@ -10,7 +10,7 @@ enum GridDemoTileStyle {
   twoLine
 }
 
-typedef void BannerTapCallback(Photo photo);
+typedef BannerTapCallback = void Function(Photo photo);
 
 const double _kMinFlingVelocity = 800.0;
 const String _kGalleryAssetsPackage = 'flutter_gallery_assets';

examples/flutter_gallery/lib/gallery/updater.dart

@@ -8,7 +8,7 @@ import 'package:flutter/material.dart';
 
 import 'package:url_launcher/url_launcher.dart';
 
-typedef Future<String> UpdateUrlFetcher();
+typedef UpdateUrlFetcher = Future<String> Function();
 
 class Updater extends StatefulWidget {
   const Updater({ @required this.updateUrlFetcher, this.child, Key key })

examples/layers/services/isolate.dart

@@ -9,8 +9,8 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 
-typedef void OnProgressListener(double completed, double total);
-typedef void OnResultListener(String result);
+typedef OnProgressListener = void Function(double completed, double total);
+typedef OnResultListener = void Function(String result);
 
 // An encapsulation of a large amount of synchronous processing.
 //

examples/layers/widgets/styled_text.dart

@@ -4,7 +4,7 @@
 
 import 'package:flutter/material.dart';
 
-typedef Widget _TextTransformer(String name, String text);
+typedef _TextTransformer = Widget Function(String name, String text);
 
 // From https://en.wikiquote.org/wiki/2001:_A_Space_Odyssey_(film)
 const String _kDialogText = '''

examples/stocks/lib/i18n/stock_messages_all.dart

@@ -12,7 +12,7 @@ import 'package:intl/src/intl_helpers.dart';
 import 'stock_messages_en.dart' as messages_en;
 import 'stock_messages_es.dart' as messages_es;
 
-typedef Future<dynamic> LibraryLoader();
+typedef LibraryLoader = Future<dynamic> Function();
 Map<String, LibraryLoader> _deferredLibraries = {
   'en': () => new Future.value(null),
   'es': () => new Future.value(null),

examples/stocks/lib/i18n/stock_messages_en.dart

@@ -12,7 +12,7 @@ final messages = new MessageLookup();
 final _keepAnalysisHappy = Intl.defaultLocale;
 
 // ignore: non_constant_identifier_names
-typedef MessageIfAbsent(String message_str, List args);
+typedef MessageIfAbsent = dynamic Function(String message_str, List args);
 
 class MessageLookup extends MessageLookupByLibrary {
   get localeName => 'en';

examples/stocks/lib/stock_home.dart

@@ -11,7 +11,7 @@ import 'stock_strings.dart';
 import 'stock_symbol_viewer.dart';
 import 'stock_types.dart';
 
-typedef void ModeUpdater(StockMode mode);
+typedef ModeUpdater = void Function(StockMode mode);
 
 enum _StockMenuItem { autorefresh, refresh, speedUp, speedDown }
 enum StockHomeTab { market, portfolio }