feat!: upgrade minimum Dart SDK version to 2.18.0 (#429)

.github/workflows/validate.yaml

@@ -29,7 +29,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: dart-lang/setup-dart@v1
         with:
-          sdk: 2.12.0 # Update when min sdk supported version of `melos` package changes.
+          sdk: 2.18.0 # Update when min sdk supported version of `melos` package changes.
       - name: "Run Melos"
         run: ./.github/workflows/scripts/install-tools.sh
 

all_lint_rules.yaml

@@ -70,11 +70,14 @@ linter:
     - cascade_invocations
     - cast_nullable_to_non_nullable
     - close_sinks
+    - collection_methods_unrelated_type
+    - combinators_ordering
     - comment_references
     - conditional_uri_does_not_exist
     - constant_identifier_names
     - control_flow_in_finally
     - curly_braces_in_flow_control_structures
+    - dangling_library_doc_comments
     - depend_on_referenced_packages
     - deprecated_consistency
     - diagnostic_describe_all_properties
@@ -84,16 +87,18 @@ linter:
     - empty_catches
     - empty_constructor_bodies
     - empty_statements
+    - enable_null_safety
     - eol_at_end_of_file
     - exhaustive_cases
     - file_names
     - flutter_style_todos
     - hash_and_equals
     - implementation_imports
-    - invariant_booleans
+    - implicit_call_tearoffs
     - iterable_contains_unrelated_type
     - join_return_with_assignment
     - leading_newlines_in_multiline_strings
+    - library_annotations
     - library_names
     - library_prefixes
     - library_private_types_in_public_api
@@ -132,7 +137,6 @@ linter:
     - prefer_constructors_over_static_methods
     - prefer_contains
     - prefer_double_quotes
-    - prefer_equal_for_default_values
     - prefer_expression_function_bodies
     - prefer_final_fields
     - prefer_final_in_for_each
@@ -186,6 +190,7 @@ linter:
     - unnecessary_getters_setters
     - unnecessary_lambdas
     - unnecessary_late
+    - unnecessary_library_directive
     - unnecessary_new
     - unnecessary_null_aware_assignments
     - unnecessary_null_aware_operator_on_extension_on_nullable
@@ -200,6 +205,7 @@ linter:
     - unnecessary_string_interpolations
     - unnecessary_this
     - unnecessary_to_list_in_spreads
+    - unreachable_from_main
     - unrelated_type_equality_checks
     - unsafe_html
     - use_build_context_synchronously
@@ -217,6 +223,7 @@ linter:
     - use_rethrow_when_possible
     - use_setters_to_change_properties
     - use_string_buffers
+    - use_string_in_part_of_directives
     - use_super_parameters
     - use_test_throws_matchers
     - use_to_and_as_if_applicable

docs/configuration/overview.mdx

@@ -150,8 +150,6 @@ Configuration for the `bootstrap` command.
 Whether to use `pubspec_overrides.yaml` for overriding workspace dependencies
 during development.
 
-Enabling this option requires Dart **2.17.0** or greater.
-
 When this option is enabled, Melos will generate a `pubspec_overrides.yaml` file
 in the root of every package during bootstrapping. This file should not be
 tracked in version control and should be added to `.gitignore`.

docs/getting-started.mdx

@@ -31,7 +31,7 @@ packages:
 The `packages` list should contain paths to the individual packages within your project. Each path
 can be defined using the [glob](https://docs.python.org/3/library/glob.html) pattern expansion format.
 
-Consider setting `usePubspecOverrides` to `true`, if you are using Dart 2.17.0 or greater:
+Consider setting `usePubspecOverrides` to `true`:
 
 ```yaml
 command:

packages/conventional_commit/lib/conventional_commit.dart

@@ -68,7 +68,7 @@ class ConventionalCommit {
     final mergeCommitPrefixMatch = _mergeCommitPrefixRegex.firstMatch(header);
     final isMergeCommit = mergeCommitPrefixMatch != null;
     final headerMatch = _conventionalCommitHeaderRegex.firstMatch(
-      isMergeCommit ? header.substring(mergeCommitPrefixMatch!.end) : header,
+      isMergeCommit ? header.substring(mergeCommitPrefixMatch.end) : header,
     );
 
     if (headerMatch == null) {

packages/conventional_commit/pubspec.yaml

@@ -6,7 +6,7 @@ repository: /~https://github.com/invertase/melos/tree/main/packages/conventional_c
 issue_tracker: /~https://github.com/invertase/melos/issues
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: '>=2.18.0 <3.0.0'
 
 dev_dependencies:
   collection: ^1.15.0

packages/melos/lib/src/command_runner/bootstrap.dart

@@ -18,11 +18,10 @@
 import 'dart:async';
 
 import '../commands/runner.dart';
-import '../workspace_configs.dart';
 import 'base.dart';
 
 class BootstrapCommand extends MelosCommand {
-  BootstrapCommand(MelosWorkspaceConfig config) : super(config) {
+  BootstrapCommand(super.config) {
     setupPackageFilterParser();
   }
 

packages/melos/lib/src/command_runner/clean.dart

@@ -16,11 +16,10 @@
  */
 
 import '../commands/runner.dart';
-import '../workspace_configs.dart';
 import 'base.dart';
 
 class CleanCommand extends MelosCommand {
-  CleanCommand(MelosWorkspaceConfig config) : super(config) {
+  CleanCommand(super.config) {
     setupPackageFilterParser();
   }
 

packages/melos/lib/src/command_runner/exec.dart

@@ -18,11 +18,10 @@
 import 'dart:io';
 
 import '../commands/runner.dart';
-import '../workspace_configs.dart';
 import 'base.dart';
 
 class ExecCommand extends MelosCommand {
-  ExecCommand(MelosWorkspaceConfig config) : super(config) {
+  ExecCommand(super.config) {
     setupPackageFilterParser();
     argParser.addOption('concurrency', defaultsTo: '5', abbr: 'c');
     argParser.addFlag(

packages/melos/lib/src/command_runner/list.dart

@@ -16,11 +16,10 @@
  */
 
 import '../commands/runner.dart';
-import '../workspace_configs.dart';
 import 'base.dart';
 
 class ListCommand extends MelosCommand {
-  ListCommand(MelosWorkspaceConfig config) : super(config) {
+  ListCommand(super.config) {
     setupPackageFilterParser();
     argParser.addFlag(
       'long',

packages/melos/lib/src/command_runner/publish.dart

@@ -16,11 +16,10 @@
  */
 
 import '../commands/runner.dart';
-import '../workspace_configs.dart';
 import 'base.dart';
 
 class PublishCommand extends MelosCommand {
-  PublishCommand(MelosWorkspaceConfig config) : super(config) {
+  PublishCommand(super.config) {
     setupPackageFilterParser();
     argParser.addFlag(
       'dry-run',

packages/melos/lib/src/command_runner/run.dart

@@ -16,11 +16,10 @@
  */
 
 import '../commands/runner.dart';
-import '../workspace_configs.dart';
 import 'base.dart';
 
 class RunCommand extends MelosCommand {
-  RunCommand(MelosWorkspaceConfig config) : super(config) {
+  RunCommand(super.config) {
     argParser.addFlag(
       'no-select',
       negatable: false,

packages/melos/lib/src/command_runner/script.dart

@@ -21,10 +21,9 @@ import 'base.dart';
 
 class ScriptCommand extends MelosCommand {
   ScriptCommand._(
-    MelosWorkspaceConfig config, {
+    super.config, {
     required this.scripts,
-  })  : assert(scripts.isNotEmpty),
-        super(config) {
+  }) : assert(scripts.isNotEmpty) {
     argParser.addFlag(
       'no-select',
       negatable: false,

packages/melos/lib/src/command_runner/version.dart

@@ -26,7 +26,6 @@ import '../commands/runner.dart';
 import '../common/utils.dart';
 import '../common/versioning.dart';
 import '../package.dart';
-import '../workspace_configs.dart';
 import 'base.dart';
 
 /// Template variable that is replaced with versioned package info in commit
@@ -38,7 +37,7 @@ const defaultCommitMessage =
     'chore(release): publish packages\n\n{$packageVersionsTemplateVar}';
 
 class VersionCommand extends MelosCommand {
-  VersionCommand(MelosWorkspaceConfig config) : super(config) {
+  VersionCommand(super.config) {
     setupPackageFilterParser();
     argParser.addFlag(
       'prerelease',

packages/melos/lib/src/commands/bootstrap.dart

@@ -64,13 +64,6 @@ mixin _BootstrapMixin on _CleanMixin {
   Future<void> _linkPackagesWithPubspecOverrides(
     MelosWorkspace workspace,
   ) async {
-    if (!workspace.isPubspecOverridesSupported) {
-      logger.warning(
-        'Dart 2.17.0 or greater is required to use Melos with '
-        'pubspec overrides.',
-      );
-    }
-
     final filteredPackages = workspace.filteredPackages.values;
 
     await Stream.fromIterable(filteredPackages).parallel(
@@ -101,10 +94,8 @@ mixin _BootstrapMixin on _CleanMixin {
 
         bootstrappedPackages.forEach(_logBootstrapSuccess);
       },
-      parallelism: workspace.config.commands.bootstrap.runPubGetInParallel &&
-              workspace.canRunPubGetConcurrently
-          ? null
-          : 1,
+      parallelism:
+          workspace.config.commands.bootstrap.runPubGetInParallel ? null : 1,
     ).drain<void>();
   }
 
@@ -185,10 +176,8 @@ mixin _BootstrapMixin on _CleanMixin {
           );
           return package;
         },
-        parallelism: workspace.config.commands.bootstrap.runPubGetInParallel &&
-                workspace.canRunPubGetConcurrently
-            ? null
-            : 1,
+        parallelism:
+            workspace.config.commands.bootstrap.runPubGetInParallel ? null : 1,
       );
 
   Future<void> _runPubGetForPackage(

packages/melos/lib/src/common/git_commit.dart

@@ -47,12 +47,12 @@ GitCommit[
 
 class RichGitCommit extends GitCommit {
   RichGitCommit({
-    required String author,
-    required String id,
-    required DateTime date,
-    required String message,
+    required super.author,
+    required super.id,
+    required super.date,
+    required super.message,
     required this.parsedMessage,
-  }) : super(author: author, id: id, date: date, message: message);
+  });
 
   static RichGitCommit? tryParse(GitCommit commit) {
     final parsedMessage = ConventionalCommit.tryParse(commit.message);

packages/melos/lib/src/common/git_repository.dart

@@ -218,8 +218,8 @@ GitLabRepository(
 }
 
 final _hostsToUrlParser = {
-  'GitHub': (Uri url) => GitHubRepository.fromUrl(url),
-  'GitLab': (Uri url) => GitLabRepository.fromUrl(url),
+  'GitHub': GitHubRepository.fromUrl,
+  'GitLab': GitLabRepository.fromUrl,
 };
 
 final _hostsToSpecParser = {

packages/melos/lib/src/common/pub_dependency_list.dart

@@ -22,10 +22,10 @@ import 'package:string_scanner/string_scanner.dart';
 
 class PubDependencyList extends VersionedEntry {
   PubDependencyList._(
-    VersionedEntry entry,
+    super.entry,
     this.sdks,
     this.sections,
-  ) : super.copy(entry);
+  ) : super.copy();
 
   factory PubDependencyList.parse(String input) {
     final scanner = StringScanner(input);

packages/melos/lib/src/common/utils.dart

@@ -154,17 +154,6 @@ Version currentDartVersion(String dartTool) {
   return Version.parse(versionString);
 }
 
-String nextDartMajorVersion([String dartTool = 'dart']) {
-  return currentDartVersion(dartTool).nextMajor.toString();
-}
-
-bool isPubspecOverridesSupported([String dartTool = 'dart']) =>
-    currentDartVersion(dartTool).compareTo(Version.parse('2.17.0-266.0.dev')) >=
-    0;
-
-bool canRunPubGetConcurrently([String dartTool = 'dart']) =>
-    currentDartVersion(dartTool).compareTo(Version.parse('2.16.0')) >= 0;
-
 T _promptWithTerminal<T>(
   T Function() runPrompt, {
   required String message,

packages/melos/lib/src/package.dart

@@ -1267,20 +1267,20 @@ Map<String, Package> _transitivelyRelatedPackages({
 }
 
 extension on PubSpec {
-  Flutter? get flutter => (unParsedYaml?['flutter'] as Map<Object?, Object?>?)
-      .let((value) => Flutter(value));
+  Flutter? get flutter =>
+      (unParsedYaml?['flutter'] as Map<Object?, Object?>?).let(Flutter.new);
 }
 
 class Flutter {
   Flutter(this._flutter);
 
   final Map<Object?, Object?> _flutter;
 
-  Plugin? get plugin => (_flutter['plugin'] as Map<Object?, Object?>?)
-      .let((value) => Plugin(value));
+  Plugin? get plugin =>
+      (_flutter['plugin'] as Map<Object?, Object?>?).let(Plugin.new);
 
-  Module? get module => (_flutter['module'] as Map<Object?, Object?>?)
-      .let((value) => Module(value));
+  Module? get module =>
+      (_flutter['module'] as Map<Object?, Object?>?).let(Module.new);
 }
 
 class Module {

packages/melos/lib/src/scripts.dart

@@ -36,7 +36,7 @@ class LifecycleHook {
 }
 
 class Scripts extends MapView<String, Script> {
-  const Scripts(Map<String, Script> map) : super(map);
+  const Scripts(super.map);
 
   factory Scripts.fromYaml(
     Map<Object?, Object?> yaml, {

packages/melos/lib/src/workspace.dart

@@ -127,12 +127,6 @@ class MelosWorkspace {
     return tool;
   }
 
-  late final bool canRunPubGetConcurrently =
-      utils.canRunPubGetConcurrently(sdkTool('dart'));
-
-  late final bool isPubspecOverridesSupported =
-      utils.isPubspecOverridesSupported(sdkTool('dart'));
-
   /// Returns a string path to the 'melos_tool' directory in this workspace.
   ///
   /// This directory should be git ignored and is used by Melos for temporary

packages/melos/pubspec.yaml

@@ -9,7 +9,10 @@ repository: /~https://github.com/invertase/melos/tree/main/packages/melos
 issue_tracker: /~https://github.com/invertase/melos/issues
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: '>=2.18.0 <3.0.0'
+
+executables:
+  melos:
 
 dependencies:
   ansi_styles: ^0.3.1
@@ -37,6 +40,3 @@ dependencies:
 dev_dependencies:
   mockito: ^5.1.0
   test: ^1.17.5
-
-executables:
-  melos: