Switch to GitHub Actions (#188)

This PR switches to use GitHub Actions instead of Travis, and updates the analysis options to use the recommended Dart lints from the lints packages.
diff --git a/.github/workflows/dart.yml b/.github/workflows/dart.yml
deleted file mode 100644
index bd08b2f..0000000
--- a/.github/workflows/dart.yml
+++ /dev/null
@@ -1,42 +0,0 @@
-# This workflow uses actions that are not certified by GitHub.
-# They are provided by a third-party and are governed by
-# separate terms of service, privacy policy, and support
-# documentation.
-
-name: Dart
-
-on:
-  push:
-    branches: [ master ]
-  pull_request:
-    branches: [ master ]
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    steps:
-      - uses: actions/checkout@v2
-
-      # Note: This workflow uses the latest stable version of the Dart SDK.
-      # You can specify other versions if desired, see documentation here:
-      # https://github.com/dart-lang/setup-dart/blob/main/README.md
-      # - uses: dart-lang/setup-dart@v1
-      - uses: dart-lang/setup-dart@9a04e6d73cca37bd455e0608d7e5092f881fd603
-
-      - name: Install dependencies
-        run: dart pub get
-
-      # Uncomment this step to verify the use of 'dart format' on each commit.
-      # - name: Verify formatting
-      #   run: dart format --output=none --set-exit-if-changed .
-
-      # Consider passing '--fatal-infos' for slightly stricter analysis.
-      - name: Analyze project source
-        run: dart analyze
-
-      # Your project will need to have tests in test/ and a dependency on
-      # package:test for this step to succeed. Note that Flutter projects will
-      # want to change this to 'flutter test'.
-      - name: Run tests
-        run: dart test
diff --git a/.github/workflows/file.yml b/.github/workflows/file.yml
new file mode 100644
index 0000000..581e9df
--- /dev/null
+++ b/.github/workflows/file.yml
@@ -0,0 +1,52 @@
+name: File Package
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+  workflow_dispatch:
+
+jobs:
+  correctness:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        package: [file, file_testing]
+    steps:
+      - uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+      - uses: dart-lang/setup-dart@9a04e6d73cca37bd455e0608d7e5092f881fd603
+        with:
+          sdk: dev
+      - name: Install ${{ matrix.package }} dependencies
+        run: |
+          cd packages/${{ matrix.package }}
+          dart pub upgrade
+      - name: Verify formatting in ${{ matrix.package }}
+        run: |
+          cd packages/${{ matrix.package }}
+          dart format --output=none --set-exit-if-changed .
+      - name: Analyze package ${{ matrix.package }} source
+        run: |
+          cd packages/${{ matrix.package }}
+          dart analyze --fatal-infos
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        package: [file]
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        sdk: [stable, beta, dev]
+    steps:
+      - uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+      - uses: dart-lang/setup-dart@9a04e6d73cca37bd455e0608d7e5092f881fd603
+        with:
+          sdk: ${{ matrix.sdk }}
+      - name: Install ${{ matrix.package }} dependencies
+        run: |
+          cd packages/${{ matrix.package }}
+          dart pub upgrade
+      - name: Run ${{ matrix.package }} Tests
+        run: |
+          cd packages/${{ matrix.package }}
+          dart pub run test -j1 -rexpanded
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 0b16974..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,8 +0,0 @@
-env:
-  - SHARD=dartfmt
-  - SHARD=analyze
-  - SHARD=tests
-install:
-  - ./dev/bots/travis_install.sh
-script:
-  - ./dev/bots/travis_script.sh
diff --git a/analysis_options.yaml b/analysis_options.yaml
index ee1a01b..8fbd2e4 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -1,165 +1,6 @@
-analyzer:
-  enable-experiment:
-    - non-nullable
-  strong-mode:
-    implicit-casts: false
-    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
+include: package:lints/recommended.yaml
 
-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
-    # - 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
-    - avoid_function_literals_in_foreach_calls
-    # - avoid_implementing_value_types # not yet tested
-    - 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 # there are plenty of valid reasons to return null
-    # - avoid_returning_null_for_future # not yet tested
-    - avoid_returning_null_for_void
-    # - avoid_returning_this # there are plenty of valid reasons to return this
-    # - avoid_setters_without_getters # not yet tested
-    # - avoid_shadowing_type_parameters # not yet tested
-    # - avoid_single_cascade_in_expression_statements # not yet tested
-    # - avoid_slow_async_io
-    - avoid_types_as_parameter_names
-    # - avoid_types_on_closure_parameters # conflicts with always_specify_types
-    - avoid_unused_constructor_parameters
-    - avoid_void_async
-    - await_only_futures
-    - camel_case_types
-    - cancel_subscriptions
-    # - cascade_invocations # not yet tested
-    # - close_sinks # not reliable enough
-    # - comment_references # blocked on https://github.com/flutter/flutter/issues/20765
-    # - constant_identifier_names # needs an opt-out https://github.com/dart-lang/linter/issues/204
-    - control_flow_in_finally
-    # - curly_braces_in_flow_control_structures # not yet tested
-    # - diagnostic_describe_all_properties # not yet tested
-    - directives_ordering
-    - empty_catches
-    - empty_constructor_bodies
-    - empty_statements
-    # - file_names # not yet tested
-    - flutter_style_todos
-    - hash_and_equals
-    - implementation_imports
-    # - invariant_booleans # too many false positives: https://github.com/dart-lang/linter/issues/811
-    - iterable_contains_unrelated_type
-    # - join_return_with_assignment # not yet tested
-    - library_names
-    - library_prefixes
-    # - lines_longer_than_80_chars # not yet tested
-    - list_remove_unrelated_type
-    # - literal_only_boolean_expressions # too many false positives: https://github.com/dart-lang/sdk/issues/34181
-    - no_adjacent_strings_in_list
-    - no_duplicate_case_values
-    - non_constant_identifier_names
-    # - null_closures  # not yet tested
-    # - 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_asserts_with_message # not yet tested
-    # - 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_double_quotes # opposite of prefer_single_quotes
-    - 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_in_for_each # not yet tested
-    # - prefer_final_locals
-    # - prefer_for_elements_to_map_fromIterable # not yet tested
-    - prefer_foreach
-    # - prefer_function_declarations_over_variables # not yet tested
-    - prefer_generic_function_type_aliases
-    # - prefer_if_elements_to_conditional_expressions # not yet tested
-    - prefer_if_null_operators
-    - prefer_initializing_formals
-    - prefer_inlined_adds
-    # - prefer_int_literals # not yet tested
-    # - prefer_interpolation_to_compose_strings # not yet tested
-    - prefer_is_empty
-    - prefer_is_not_empty
-    - prefer_iterable_whereType
-    # - prefer_mixin # https://github.com/dart-lang/language/issues/32
-    # - prefer_null_aware_operators # disable until NNBD, see https://github.com/flutter/flutter/pull/32711#issuecomment-492930932
-    - prefer_single_quotes
-    - prefer_spread_collections
-    - prefer_typing_uninitialized_variables
-    # - prefer_void_to_null
-    # - provide_deprecation_message # not yet tested
-    - public_member_api_docs
-    - recursive_getters
-    - slash_for_doc_comments
-    # - sort_child_properties_last # not yet tested
-    - sort_constructors_first
-    - sort_pub_dependencies
-    - sort_unnamed_constructors_first
-    - test_types_in_equals
-    - throw_in_finally
-    # - type_annotate_public_apis # subset of always_specify_types
-    - type_init_formals
-    - unawaited_futures
-    # - unnecessary_await_in_return # not yet tested
-    - unnecessary_brace_in_string_interps
-    - unnecessary_const
-    - unnecessary_getters_setters
-    # - unnecessary_lambdas # has false positives: https://github.com/dart-lang/linter/issues/498
-    - unnecessary_new
-    - unnecessary_null_aware_assignments
-    - unnecessary_null_in_if_null_operators
-    - unnecessary_overrides
-    - unnecessary_parenthesis
-    - unnecessary_statements
-    - unnecessary_this
-    - unrelated_type_equality_checks
-    # - unsafe_html # not yet tested
-    - use_full_hex_values_for_flutter_colors
-    # - use_function_type_syntax_for_parameters # not yet tested
-    - use_rethrow_when_possible
-    # - use_setters_to_change_properties # not yet tested
-    # - use_string_buffers # has false positives: https://github.com/dart-lang/sdk/issues/34182
-    # - 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
+analyzer:
+  errors:
+    # Allow having TODOs in the code
+    todo: ignore
diff --git a/dev/bots/travis_install.sh b/dev/bots/travis_install.sh
deleted file mode 100755
index ff2f932..0000000
--- a/dev/bots/travis_install.sh
+++ /dev/null
@@ -1,20 +0,0 @@
-#!/bin/bash
-set -ex
-
-echo "$PWD"
-
-export PATH="$HOME/dart-sdk/bin:$PATH"
-export ROOT="$PWD"
-export PACKAGES=("file" "file_testing")
-
-wget \
-    --tries=3 \
-    --output-document=dart-sdk.zip \
-    https://storage.googleapis.com/dart-archive/channels/dev/release/latest/sdk/dartsdk-linux-x64-release.zip
-echo "Unzipping dart-sdk..."
-unzip dart-sdk.zip -d "$HOME" > /dev/null
-
-for package in "${PACKAGES[@]}"; do
-  cd $ROOT/packages/$package
-  pub get
-done
diff --git a/dev/bots/travis_script.sh b/dev/bots/travis_script.sh
deleted file mode 100755
index fe55e57..0000000
--- a/dev/bots/travis_script.sh
+++ /dev/null
@@ -1,20 +0,0 @@
-#!/bin/bash
-set -ex
-
-export PATH="$HOME/dart-sdk/bin:$PATH"
-export ROOT="$PWD"
-export PACKAGES=("file" "file_testing")
-
-if [[ "$SHARD" == "dartfmt" ]]; then
-  dartfmt --dry-run --set-exit-if-changed packages || exit $?
-elif [[ "$SHARD" == "analyze" ]]; then
-  for package in "${PACKAGES[@]}"; do
-    echo "Analyzing packages/$package"
-    cd $ROOT/packages/$package
-    dartanalyzer --options=$ROOT/analysis_options.yaml . || exit $?
-  done
-else
-  # tests shard
-  cd $ROOT/packages/file
-  pub run test -j1 -rexpanded || exit $?
-fi
diff --git a/packages/file/lib/src/backends/chroot/chroot_file_system.dart b/packages/file/lib/src/backends/chroot/chroot_file_system.dart
index ddf752e..6889c98 100644
--- a/packages/file/lib/src/backends/chroot/chroot_file_system.dart
+++ b/packages/file/lib/src/backends/chroot/chroot_file_system.dart
@@ -277,7 +277,7 @@
     }
 
     String getCurrentPath() => root + ctx.joinAll(ledger);
-    Set<String> breadcrumbs = Set<String>();
+    Set<String> breadcrumbs = <String>{};
     while (parts.isNotEmpty) {
       String segment = parts.removeAt(0);
       if (segment == _thisDir) {
diff --git a/packages/file/lib/src/backends/memory/memory_directory.dart b/packages/file/lib/src/backends/memory/memory_directory.dart
index 9288f7e..ec8ad45 100644
--- a/packages/file/lib/src/backends/memory/memory_directory.dart
+++ b/packages/file/lib/src/backends/memory/memory_directory.dart
@@ -136,7 +136,7 @@
         path.endsWith(fileSystem.path.separator)
             ? path.substring(0, path.length - 1)
             : path,
-        Set<LinkNode>(),
+        <LinkNode>{},
       ),
     ];
     while (tasks.isNotEmpty) {
diff --git a/packages/file/lib/src/backends/memory/memory_file_system_entity.dart b/packages/file/lib/src/backends/memory/memory_file_system_entity.dart
index c2f9c4d..ad987d7 100644
--- a/packages/file/lib/src/backends/memory/memory_file_system_entity.dart
+++ b/packages/file/lib/src/backends/memory/memory_file_system_entity.dart
@@ -181,7 +181,8 @@
   /// resolve it to its target prior to returning it.
   @protected
   Node? internalCreateSync({
-    required Node? createChild(DirectoryNode parent, bool isFinalSegment),
+    required Node? Function(DirectoryNode parent, bool isFinalSegment)
+        createChild,
     bool followTailLink = false,
     bool visitLinks = false,
   }) {
diff --git a/packages/file/lib/src/backends/memory/node.dart b/packages/file/lib/src/backends/memory/node.dart
index 4cbb25c..ae4d3f7 100644
--- a/packages/file/lib/src/backends/memory/node.dart
+++ b/packages/file/lib/src/backends/memory/node.dart
@@ -306,7 +306,8 @@
   /// target cannot be traversed into, a [FileSystemException] will be thrown,
   /// and [tailVisitor] will not be invoked.
   Node getReferent({
-    Node? tailVisitor(DirectoryNode parent, String childName, Node? child)?,
+    Node? Function(DirectoryNode parent, String childName, Node? child)?
+        tailVisitor,
   }) {
     Node? referent = fs.findNode(
       target,
diff --git a/packages/file/lib/src/backends/memory/utils.dart b/packages/file/lib/src/backends/memory/utils.dart
index 109baed..eec9980 100644
--- a/packages/file/lib/src/backends/memory/utils.dart
+++ b/packages/file/lib/src/backends/memory/utils.dart
@@ -82,10 +82,11 @@
   LinkNode link,
   PathGenerator path, {
   List<String>? ledger,
-  Node? tailVisitor(DirectoryNode parent, String childName, Node? child)?,
+  Node? Function(DirectoryNode parent, String childName, Node? child)?
+      tailVisitor,
 }) {
   // Record a breadcrumb trail to guard against symlink loops.
-  Set<LinkNode> breadcrumbs = Set<LinkNode>();
+  Set<LinkNode> breadcrumbs = <LinkNode>{};
 
   Node node = link;
   while (isLink(node)) {
diff --git a/packages/file/lib/src/interface/error_codes.dart b/packages/file/lib/src/interface/error_codes.dart
index 2629a5d..8943538 100644
--- a/packages/file/lib/src/interface/error_codes.dart
+++ b/packages/file/lib/src/interface/error_codes.dart
@@ -167,7 +167,7 @@
   // ignore: non_constant_identifier_names
   static int get EXDEV => _platform((_Codes codes) => codes.exdev);
 
-  static int _platform(int getCode(_Codes codes)) {
+  static int _platform(int Function(_Codes codes) getCode) {
     _Codes codes = (_platforms[operatingSystem] ?? _platforms['linux'])!;
     return getCode(codes);
   }
diff --git a/packages/file/pubspec.yaml b/packages/file/pubspec.yaml
index 3037f3a..f6d82de 100644
--- a/packages/file/pubspec.yaml
+++ b/packages/file/pubspec.yaml
@@ -15,4 +15,5 @@
 
 dev_dependencies:
   file_testing: '>=3.0.0 <4.0.0'
+  lints: ^1.0.1
   test: '^1.16.0'
diff --git a/packages/file/test/common_tests.dart b/packages/file/test/common_tests.dart
index 207c082..9e97c15 100644
--- a/packages/file/test/common_tests.dart
+++ b/packages/file/test/common_tests.dart
@@ -64,7 +64,7 @@
     late String root;
     List<String> stack = <String>[];
 
-    void skipIfNecessary(String description, void callback()) {
+    void skipIfNecessary(String description, void Function() callback) {
       stack.add(description);
       bool matchesCurrentFrame(String input) =>
           RegExp('^$input\$').hasMatch(stack.join(' > '));
@@ -80,11 +80,11 @@
       tearDowns = <SetUpTearDown>[];
     });
 
-    void setUp(FutureOr<void> callback()) {
+    void setUp(FutureOr<void> Function() callback) {
       testpkg.setUp(replay == null ? callback : () => setUps.add(callback));
     }
 
-    void tearDown(FutureOr<void> callback()) {
+    void tearDown(FutureOr<void> Function() callback) {
       if (replay == null) {
         testpkg.tearDown(callback);
       } else {
@@ -92,10 +92,11 @@
       }
     }
 
-    void group(String description, void body()) =>
+    void group(String description, void Function() body) =>
         skipIfNecessary(description, () => testpkg.group(description, body));
 
-    void test(String description, FutureOr<void> body(), {dynamic skip}) =>
+    void test(String description, FutureOr<void> Function() body,
+            {dynamic skip}) =>
         skipIfNecessary(description, () {
           if (replay == null) {
             testpkg.test(description, body, skip: skip);
@@ -866,7 +867,7 @@
         test('throwsIfLoopInLinkChain', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
           fs.link(ns('/bar')).createSync(ns('/baz'));
-          fs.link(ns('/baz'))..createSync(ns('/foo'));
+          fs.link(ns('/baz')).createSync(ns('/foo'));
           expectFileSystemException(
             anyOf(ErrorCodes.EMLINK, ErrorCodes.ELOOP),
             () {
@@ -1433,7 +1434,7 @@
               FileSystemEntityType.link);
           expect(fs.file(ns('/foo')).readAsStringSync(), 'foo');
           expect(fs.file(ns('/bar')).readAsStringSync(), 'foo');
-        });
+        }, skip: io.Platform.isWindows /* No links on Windows */);
 
         test('throwsIfDestinationExistsAsLinkToDirectory', () {
           File f = fs.file(ns('/foo'))..createSync();
@@ -1518,7 +1519,7 @@
               FileSystemEntityType.link);
           expect(fs.file(ns('/foo/bar')).readAsStringSync(), 'qux');
           expect(fs.file(ns('/baz/qux')).readAsStringSync(), 'qux');
-        });
+        }, skip: io.Platform.isWindows /* No links on Windows */);
       });
 
       group('length', () {
@@ -3093,7 +3094,7 @@
 
         test('unlinksIfTargetIsLinkLoop', () {
           Link l = fs.link(ns('/foo'))..createSync(ns('/bar'));
-          fs.link(ns('/bar'))..createSync(ns('/foo'));
+          fs.link(ns('/bar')).createSync(ns('/foo'));
           l.deleteSync();
           expect(fs.typeSync(ns('/foo'), followLinks: false),
               FileSystemEntityType.notFound);
diff --git a/packages/file_testing/lib/src/testing/core_matchers.dart b/packages/file_testing/lib/src/testing/core_matchers.dart
index 70765c4..f58539f 100644
--- a/packages/file_testing/lib/src/testing/core_matchers.dart
+++ b/packages/file_testing/lib/src/testing/core_matchers.dart
@@ -61,7 +61,7 @@
 ///
 /// See also:
 ///   - [ErrorCodes]
-void expectFileSystemException(dynamic osErrorCode, void callback()) {
+void expectFileSystemException(dynamic osErrorCode, void Function() callback) {
   expect(callback, throwsFileSystemException(osErrorCode));
 }
 
diff --git a/packages/file_testing/pubspec.yaml b/packages/file_testing/pubspec.yaml
index 85b6de4..e4c6ca1 100644
--- a/packages/file_testing/pubspec.yaml
+++ b/packages/file_testing/pubspec.yaml
@@ -8,3 +8,5 @@
 
 dependencies:
   test: ^1.16.0
+dev_dependencies: 
+  lints: ^1.0.1
diff --git a/pubspec.yaml b/pubspec.yaml
new file mode 100644
index 0000000..2269e8f
--- /dev/null
+++ b/pubspec.yaml
@@ -0,0 +1,10 @@
+name: file_dart_repository
+version: 0.1.0
+description: The repository for the file.dart package
+publish_to: none
+
+environment:
+  sdk: '>=2.12.0 <3.0.0'
+
+dev_dependencies:
+  lints: ^1.0.1