[native_assets_builder] Speedup builds for 0 or 1 packages with native assets

pkgs/native_assets_builder/CHANGELOG.md

@@ -1,12 +1,17 @@
+## 0.2.3
+
+- Quicker build planning for 0 or 1 packages with native assets
+  ([#128](https://github.com/dart-lang/native/issues/128)).
+
 ## 0.2.2
 
 - Take a `PackageLayout` argument for `build` and `dryRun`
-  [flutter#134427](https://github.com/flutter/flutter/issues/134427).
+  ([flutter#134427](https://github.com/flutter/flutter/issues/134427)).
 
 ## 0.2.1
 
 - Provide a `PackageLayout` constructor for already parsed `PackageConfig`
-  [flutter#134427](https://github.com/flutter/flutter/issues/134427).
+  ([flutter#134427](https://github.com/flutter/flutter/issues/134427)).
 
 ## 0.2.0
 

pkgs/native_assets_builder/lib/src/build_runner/build_runner.dart

@@ -7,6 +7,7 @@ import 'dart:io';
 
 import 'package:logging/logging.dart';
 import 'package:native_assets_cli/native_assets_cli.dart';
+import 'package:package_config/package_config.dart';
 
 import '../package_layout/package_layout.dart';
 import '../utils/run_process.dart';
@@ -47,27 +48,38 @@ class NativeAssetsBuildRunner {
     packageLayout ??= await PackageLayout.fromRootPackageRoot(workingDirectory);
     final packagesWithNativeAssets =
         await packageLayout.packagesWithNativeAssets;
-    final planner = await NativeAssetsBuildPlanner.fromRootPackageRoot(
-      rootPackageRoot: packageLayout.rootPackageRoot,
-      packagesWithNativeAssets: packagesWithNativeAssets,
-      dartExecutable: Uri.file(Platform.resolvedExecutable),
-      logger: logger,
-    );
-    final (plan, planSuccess) = planner.plan();
-    if (!planSuccess) {
-      return _BuildResultImpl(
-        assets: [],
-        dependencies: [],
-        success: false,
+    final List<Package> buildPlan;
+    final PackageGraph packageGraph;
+    if (packagesWithNativeAssets.length <= 1) {
+      buildPlan = packagesWithNativeAssets;
+      packageGraph = PackageGraph({
+        for (final p in packagesWithNativeAssets) p.name: [],
+      });
+    } else {
+      final planner = await NativeAssetsBuildPlanner.fromRootPackageRoot(
+        rootPackageRoot: packageLayout.rootPackageRoot,
+        packagesWithNativeAssets: packagesWithNativeAssets,
+        dartExecutable: Uri.file(Platform.resolvedExecutable),
+        logger: logger,
       );
+      final (plan, planSuccess) = planner.plan();
+      if (!planSuccess) {
+        return _BuildResultImpl(
+          assets: [],
+          dependencies: [],
+          success: false,
+        );
+      }
+      buildPlan = plan;
+      packageGraph = planner.packageGraph;
     }
     final assets = <Asset>[];
     final dependencies = <Uri>[];
     final metadata = <String, Metadata>{};
     var success = true;
-    for (final package in plan) {
+    for (final package in buildPlan) {
       final dependencyMetadata = _metadataForPackage(
-        packageGraph: planner.packageGraph,
+        packageGraph: packageGraph,
         packageName: package.name,
         targetMetadata: metadata,
       );
@@ -123,22 +135,28 @@ class NativeAssetsBuildRunner {
     packageLayout ??= await PackageLayout.fromRootPackageRoot(workingDirectory);
     final packagesWithNativeAssets =
         await packageLayout.packagesWithNativeAssets;
-    final planner = await NativeAssetsBuildPlanner.fromRootPackageRoot(
-      rootPackageRoot: packageLayout.rootPackageRoot,
-      packagesWithNativeAssets: packagesWithNativeAssets,
-      dartExecutable: Uri.file(Platform.resolvedExecutable),
-      logger: logger,
-    );
-    final (plan, planSuccess) = planner.plan();
-    if (!planSuccess) {
-      return _DryRunResultImpl(
-        assets: [],
-        success: false,
+    final List<Package> buildPlan;
+    if (packagesWithNativeAssets.length <= 1) {
+      buildPlan = packagesWithNativeAssets;
+    } else {
+      final planner = await NativeAssetsBuildPlanner.fromRootPackageRoot(
+        rootPackageRoot: packageLayout.rootPackageRoot,
+        packagesWithNativeAssets: packagesWithNativeAssets,
+        dartExecutable: Uri.file(Platform.resolvedExecutable),
+        logger: logger,
       );
+      final (plan, planSuccess) = planner.plan();
+      if (!planSuccess) {
+        return _DryRunResultImpl(
+          assets: [],
+          success: false,
+        );
+      }
+      buildPlan = plan;
     }
     final assets = <Asset>[];
     var success = true;
-    for (final package in plan) {
+    for (final package in buildPlan) {
       final config = await _cliConfigDryRun(
         packageName: package.name,
         packageRoot: packageLayout.packageRoot(package.name),

pkgs/native_assets_builder/pubspec.yaml

@@ -1,7 +1,7 @@
 name: native_assets_builder
 description: >-
   This package is the backend that invokes top-level `build.dart` scripts.
-version: 0.2.2
+version: 0.2.3
 repository: https://github.com/dart-lang/native/tree/main/pkgs/native_assets_builder
 
 environment: