Reland "Add flag controlling creation of .packages file."

lib/src/command/add.dart

@@ -94,6 +94,8 @@ class AddCommand extends PubCommand {
         help: 'Build executables in immediate dependencies.');
     argParser.addOption('directory',
         abbr: 'C', help: 'Run this in the directory <dir>.', valueHelp: 'dir');
+    argParser.addFlag('legacy-packages-file',
+        help: 'Generate the legacy ".packages" file', negatable: false);
   }
 
   @override
@@ -165,7 +167,8 @@ class AddCommand extends PubCommand {
           .acquireDependencies(SolveType.get,
               dryRun: true,
               precompile: argResults['precompile'],
-              analytics: analytics);
+              analytics: analytics,
+              generateDotPackages: false);
     } else {
       /// Update the `pubspec.yaml` before calling [acquireDependencies] to
       /// ensure that the modification timestamp on `pubspec.lock` and
@@ -180,6 +183,7 @@ class AddCommand extends PubCommand {
         SolveType.get,
         precompile: argResults['precompile'],
         analytics: analytics,
+        generateDotPackages: argResults['legacy-packages-file'],
       );
 
       if (argResults['example'] && entrypoint.example != null) {
@@ -188,6 +192,7 @@ class AddCommand extends PubCommand {
           precompile: argResults['precompile'],
           onlyReportSuccessOrFailure: true,
           analytics: analytics,
+          generateDotPackages: argResults['legacy-packages-file'],
         );
       }
     }

lib/src/command/downgrade.dart

@@ -42,6 +42,8 @@ class DowngradeCommand extends PubCommand {
 
     argParser.addOption('directory',
         abbr: 'C', help: 'Run this in the directory<dir>.', valueHelp: 'dir');
+    argParser.addFlag('legacy-packages-file',
+        help: 'Generate the legacy ".packages" file', negatable: false);
   }
 
   @override
@@ -57,6 +59,7 @@ class DowngradeCommand extends PubCommand {
       unlock: argResults.rest,
       dryRun: dryRun,
       analytics: analytics,
+      generateDotPackages: argResults['legacy-packages-file'],
     );
     var example = entrypoint.example;
     if (argResults['example'] && example != null) {
@@ -66,6 +69,7 @@ class DowngradeCommand extends PubCommand {
         dryRun: dryRun,
         onlyReportSuccessOrFailure: true,
         analytics: analytics,
+        generateDotPackages: argResults['legacy-packages-file'],
       );
     }
 

lib/src/command/get.dart

@@ -33,6 +33,9 @@ class GetCommand extends PubCommand {
 
     argParser.addFlag('packages-dir', hide: true);
 
+    argParser.addFlag('legacy-packages-file',
+        help: 'Generate the legacy ".packages" file', negatable: false);
+
     argParser.addFlag(
       'example',
       help: 'Also run in `example/` (if it exists).',
@@ -53,16 +56,20 @@ class GetCommand extends PubCommand {
       SolveType.get,
       dryRun: argResults['dry-run'],
       precompile: argResults['precompile'],
+      generateDotPackages: argResults['legacy-packages-file'],
       analytics: analytics,
     );
 
     var example = entrypoint.example;
     if (argResults['example'] && example != null) {
-      await example.acquireDependencies(SolveType.get,
-          dryRun: argResults['dry-run'],
-          precompile: argResults['precompile'],
-          onlyReportSuccessOrFailure: true,
-          analytics: analytics);
+      await example.acquireDependencies(
+        SolveType.get,
+        dryRun: argResults['dry-run'],
+        precompile: argResults['precompile'],
+        generateDotPackages: argResults['legacy-packages-file'],
+        analytics: analytics,
+        onlyReportSuccessOrFailure: true,
+      );
     }
   }
 }

lib/src/command/remove.dart

@@ -50,6 +50,9 @@ class RemoveCommand extends PubCommand {
 
     argParser.addOption('directory',
         abbr: 'C', help: 'Run this in the directory<dir>.', valueHelp: 'dir');
+
+    argParser.addFlag('legacy-packages-file',
+        help: 'Generate the legacy ".packages" file', negatable: false);
   }
 
   @override
@@ -69,7 +72,8 @@ class RemoveCommand extends PubCommand {
           .acquireDependencies(SolveType.get,
               precompile: argResults['precompile'],
               dryRun: true,
-              analytics: null);
+              analytics: null,
+              generateDotPackages: false);
     } else {
       /// Update the pubspec.
       _writeRemovalToPubspec(packages);
@@ -81,6 +85,7 @@ class RemoveCommand extends PubCommand {
         SolveType.get,
         precompile: argResults['precompile'],
         analytics: analytics,
+        generateDotPackages: argResults['legacy-packages-file'],
       );
 
       var example = entrypoint.example;
@@ -90,6 +95,7 @@ class RemoveCommand extends PubCommand {
           precompile: argResults['precompile'],
           onlyReportSuccessOrFailure: true,
           analytics: analytics,
+          generateDotPackages: argResults['legacy-packages-file'],
         );
       }
     }

lib/src/command/upgrade.dart

@@ -56,6 +56,9 @@ class UpgradeCommand extends PubCommand {
 
     argParser.addFlag('packages-dir', hide: true);
 
+    argParser.addFlag('legacy-packages-file',
+        help: 'Generate the legacy ".packages" file', negatable: false);
+
     argParser.addFlag(
       'major-versions',
       help: 'Upgrades packages to their latest resolvable versions, '
@@ -80,6 +83,8 @@ class UpgradeCommand extends PubCommand {
 
   bool get _precompile => argResults['precompile'];
 
+  bool get _packagesFile => argResults['legacy-packages-file'];
+
   bool get _upgradeNullSafety =>
       argResults['nullsafety'] || argResults['null-safety'];
 
@@ -126,6 +131,7 @@ class UpgradeCommand extends PubCommand {
       dryRun: _dryRun,
       precompile: _precompile,
       onlyReportSuccessOrFailure: onlySummary,
+      generateDotPackages: _packagesFile,
       analytics: analytics,
     );
     _showOfflineWarning();
@@ -237,6 +243,7 @@ be direct 'dependencies' or 'dev_dependencies', following packages are not:
         dryRun: true,
         precompile: _precompile,
         analytics: null, // No analytics for dry-run
+        generateDotPackages: false,
       );
     } else {
       if (changes.isNotEmpty) {
@@ -249,6 +256,7 @@ be direct 'dependencies' or 'dev_dependencies', following packages are not:
         SolveType.get,
         precompile: _precompile,
         analytics: analytics,
+        generateDotPackages: argResults['legacy-packages-file'],
       );
     }
 
@@ -333,6 +341,7 @@ be direct 'dependencies' or 'dev_dependencies', following packages are not:
         dryRun: true,
         precompile: _precompile,
         analytics: null,
+        generateDotPackages: false,
       );
     } else {
       if (changes.isNotEmpty) {
@@ -345,6 +354,7 @@ be direct 'dependencies' or 'dev_dependencies', following packages are not:
         SolveType.upgrade,
         precompile: _precompile,
         analytics: analytics,
+        generateDotPackages: argResults['legacy-packages-file'],
       );
     }
 

lib/src/entrypoint.dart

@@ -224,13 +224,17 @@ class Entrypoint {
   Entrypoint? _example;
 
   /// Writes .packages and .dart_tool/package_config.json
-  Future<void> writePackagesFiles() async {
+  Future<void> writePackagesFiles({bool generateDotPackages = false}) async {
     final entrypointName = isGlobal ? null : root.name;
-    writeTextFile(
-        packagesFile,
-        lockFile.packagesFile(cache,
-            entrypoint: entrypointName,
-            relativeFrom: isGlobal ? null : root.dir));
+    if (generateDotPackages) {
+      writeTextFile(
+          packagesFile,
+          lockFile.packagesFile(cache,
+              entrypoint: entrypointName,
+              relativeFrom: isGlobal ? null : root.dir));
+    } else {
+      tryDeleteEntry(packagesFile);
+    }
     ensureDir(p.dirname(packageConfigFile));
     writeTextFile(
         packageConfigFile,
@@ -268,6 +272,7 @@ class Entrypoint {
     Iterable<String>? unlock,
     bool dryRun = false,
     bool precompile = false,
+    required bool generateDotPackages,
     required PubAnalytics? analytics,
     bool onlyReportSuccessOrFailure = false,
   }) async {
@@ -341,7 +346,7 @@ class Entrypoint {
       /// have to reload and reparse all the pubspecs.
       _packageGraph = PackageGraph.fromSolveResult(this, result);
 
-      await writePackagesFiles();
+      await writePackagesFiles(generateDotPackages: generateDotPackages);
 
       try {
         if (precompile) {

lib/src/executable.dart

@@ -308,6 +308,7 @@ Future<DartExecutableWithPackageConfig> getExecutableForCommand(
         () => entrypoint.acquireDependencies(
           SolveType.get,
           analytics: analytics,
+          generateDotPackages: false,
         ),
       );
     } on ApplicationException catch (e) {

lib/src/global_packages.dart

@@ -159,7 +159,11 @@ class GlobalPackages {
     var entrypoint = Entrypoint(path, cache);
 
     // Get the package's dependencies.
-    await entrypoint.acquireDependencies(SolveType.get, analytics: analytics);
+    await entrypoint.acquireDependencies(
+      SolveType.get,
+      analytics: analytics,
+      generateDotPackages: false,
+    );
     var name = entrypoint.root.name;
     _describeActive(name, cache);
 

lib/src/package_config.dart

@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'dart:convert';
+
 import 'package:pub_semver/pub_semver.dart';
 
 import 'language_version.dart';
@@ -160,8 +162,6 @@ class PackageConfigEntry {
   /// Given as `<major>.<minor>` version, similar to the `// @dart = X.Y`
   /// comment. This is derived from the lower-bound on the Dart SDK requirement
   /// in the `pubspec.yaml` for the given package.
-  ///
-  /// `null` if not given.
   LanguageVersion? languageVersion;
 
   /// Additional properties not in the specification for the
@@ -173,10 +173,8 @@ class PackageConfigEntry {
     required this.rootUri,
     this.packageUri,
     this.languageVersion,
-    this.additionalProperties,
-  }) {
-    additionalProperties ??= {};
-  }
+    this.additionalProperties = const {},
+  });
 
   /// Create [PackageConfigEntry] from JSON [data].
   ///
@@ -249,7 +247,13 @@ class PackageConfigEntry {
   Map<String, Object?> toJson() => {
         'name': name,
         'rootUri': rootUri.toString(),
-        if (packageUri != null) 'packageUri': packageUri?.toString(),
+        if (packageUri != null) 'packageUri': packageUri.toString(),
         if (languageVersion != null) 'languageVersion': '$languageVersion',
       }..addAll(additionalProperties ?? {});
+
+  @override
+  String toString() {
+    // TODO: implement toString
+    return JsonEncoder.withIndent('  ').convert(toJson());
+  }
 }

test/add/common/add_test.dart

@@ -46,7 +46,9 @@ void main() {
       await pubAdd(args: ['foo:1.2.3']);
 
       await d.cacheDir({'foo': '1.2.3'}).validate();
-      await d.appPackagesFile({'foo': '1.2.3'}).validate();
+      await d.appPackageConfigFile([
+        d.packageConfigEntry(name: 'foo', version: '1.2.3'),
+      ]).validate();
       await d.appDir({'foo': '1.2.3'}).validate();
     });
 
@@ -62,8 +64,11 @@ void main() {
 
       await d.cacheDir(
           {'foo': '1.2.3', 'bar': '1.1.0', 'baz': '2.5.3'}).validate();
-      await d.appPackagesFile(
-          {'foo': '1.2.3', 'bar': '1.1.0', 'baz': '2.5.3'}).validate();
+      await d.appPackageConfigFile([
+        d.packageConfigEntry(name: 'foo', version: '1.2.3'),
+        d.packageConfigEntry(name: 'bar', version: '1.1.0'),
+        d.packageConfigEntry(name: 'baz', version: '2.5.3'),
+      ]).validate();
       await d
           .appDir({'foo': '1.2.3', 'bar': '1.1.0', 'baz': '2.5.3'}).validate();
     });
@@ -90,7 +95,9 @@ void main() {
       await pubAdd(args: ['foo:1.2.3']);
 
       await d.cacheDir({'foo': '1.2.3'}).validate();
-      await d.appPackagesFile({'foo': '1.2.3'}).validate();
+      await d.appPackageConfigFile([
+        d.packageConfigEntry(name: 'foo', version: '1.2.3'),
+      ]).validate();
 
       await d.dir(appPath, [
         d.pubspec({
@@ -136,7 +143,9 @@ void main() {
       await pubAdd(args: ['foo:1.2.3']);
 
       await d.cacheDir({'foo': '1.2.3'}).validate();
-      await d.appPackagesFile({'foo': '1.2.3'}).validate();
+      await d.appPackageConfigFile([
+        d.packageConfigEntry(name: 'foo', version: '1.2.3'),
+      ]).validate();
       await d.appDir({'foo': '1.2.3'}).validate();
     });
 
@@ -217,7 +226,9 @@ environment:
               'adding it to dependencies instead.'));
 
       await d.cacheDir({'foo': '1.2.3'}).validate();
-      await d.appPackagesFile({'foo': '1.2.3'}).validate();
+      await d.appPackageConfigFile([
+        d.packageConfigEntry(name: 'foo', version: '1.2.3'),
+      ]).validate();
 
       await d.dir(appPath, [
         d.pubspec({
@@ -244,7 +255,9 @@ environment:
         await pubAdd(args: ['foo']);
 
         await d.cacheDir({'foo': '1.2.2'}).validate();
-        await d.appPackagesFile({'foo': '1.2.2'}).validate();
+        await d.appPackageConfigFile([
+          d.packageConfigEntry(name: 'foo', version: '1.2.2'),
+        ]).validate();
         await d.dir(appPath, [
           d.pubspec({
             'name': 'myapp',
@@ -456,7 +469,9 @@ environment:
 
       await pubAdd(args: ['--dev', 'foo:1.2.3']);
 
-      await d.appPackagesFile({'foo': '1.2.3'}).validate();
+      await d.appPackageConfigFile([
+        d.packageConfigEntry(name: 'foo', version: '1.2.3'),
+      ]).validate();
 
       await d.dir(appPath, [
         d.pubspec({
@@ -566,7 +581,9 @@ environment:
         await pubAdd(args: ['foo', '--dev']);
 
         await d.cacheDir({'foo': '1.2.2'}).validate();
-        await d.appPackagesFile({'foo': '1.2.2'}).validate();
+        await d.appPackageConfigFile([
+          d.packageConfigEntry(name: 'foo', version: '1.2.2'),
+        ]).validate();
         await d.dir(appPath, [
           d.pubspec({
             'name': 'myapp',