Use frontend_server from the Dart SDK (#97078)

packages/flutter_tools/lib/src/artifacts.dart

@@ -346,10 +346,10 @@ class CachedArtifacts implements Artifacts {
   ) {
     switch (artifact) {
       case HostArtifact.engineDartSdkPath:
-        final String path = _dartSdkPath(_fileSystem);
+        final String path = _dartSdkPath(_cache);
         return _fileSystem.directory(path);
       case HostArtifact.engineDartBinary:
-        final String path = _fileSystem.path.join(_dartSdkPath(_fileSystem), 'bin', _hostArtifactToFileName(artifact, _platform.isWindows));
+        final String path = _fileSystem.path.join(_dartSdkPath(_cache), 'bin', _hostArtifactToFileName(artifact, _platform.isWindows));
         return _fileSystem.file(path);
       case HostArtifact.flutterWebSdk:
         final String path = _getFlutterWebSdkPath();
@@ -398,7 +398,7 @@ class CachedArtifacts implements Artifacts {
       case HostArtifact.dart2jsSnapshot:
       case HostArtifact.dartdevcSnapshot:
       case HostArtifact.kernelWorkerSnapshot:
-        final String path = _fileSystem.path.join(_dartSdkPath(_fileSystem), 'bin', 'snapshots', _hostArtifactToFileName(artifact, _platform.isWindows));
+        final String path = _fileSystem.path.join(_dartSdkPath(_cache), 'bin', 'snapshots', _hostArtifactToFileName(artifact, _platform.isWindows));
         return _fileSystem.file(path);
       case HostArtifact.iosDeploy:
         final String artifactFileName = _hostArtifactToFileName(artifact, _platform.isWindows);
@@ -461,13 +461,11 @@ class CachedArtifacts implements Artifacts {
   String _getAndroidArtifactPath(Artifact artifact, TargetPlatform platform, BuildMode mode) {
     final String engineDir = _getEngineArtifactsPath(platform, mode)!;
     switch (artifact) {
-      case Artifact.frontendServerSnapshotForEngineDartSdk:
-        assert(mode != BuildMode.debug, 'Artifact $artifact only available in non-debug mode.');
-        return _fileSystem.path.join(engineDir, _artifactToFileName(artifact));
       case Artifact.genSnapshot:
         assert(mode != BuildMode.debug, 'Artifact $artifact only available in non-debug mode.');
         final String hostPlatform = getNameForHostPlatform(getCurrentHostPlatform());
         return _fileSystem.path.join(engineDir, hostPlatform, _artifactToFileName(artifact));
+      case Artifact.frontendServerSnapshotForEngineDartSdk:
       case Artifact.constFinder:
       case Artifact.flutterFramework:
       case Artifact.flutterMacOSFramework:
@@ -499,13 +497,13 @@ class CachedArtifacts implements Artifacts {
     switch (artifact) {
       case Artifact.genSnapshot:
       case Artifact.flutterXcframework:
-      case Artifact.frontendServerSnapshotForEngineDartSdk:
         final String artifactFileName = _artifactToFileName(artifact)!;
         final String engineDir = _getEngineArtifactsPath(platform, mode)!;
         return _fileSystem.path.join(engineDir, artifactFileName);
       case Artifact.flutterFramework:
         final String engineDir = _getEngineArtifactsPath(platform, mode)!;
         return _getIosEngineArtifactPath(engineDir, environmentType, _fileSystem);
+      case Artifact.frontendServerSnapshotForEngineDartSdk:
       case Artifact.constFinder:
       case Artifact.flutterMacOSFramework:
       case Artifact.flutterMacOSPodspec:
@@ -596,10 +594,14 @@ class CachedArtifacts implements Artifacts {
         // For script snapshots any gen_snapshot binary will do. Returning gen_snapshot for
         // android_arm in profile mode because it is available on all supported host platforms.
         return _getAndroidArtifactPath(artifact, TargetPlatform.android_arm, BuildMode.profile);
+      case Artifact.frontendServerSnapshotForEngineDartSdk:
+        return _fileSystem.path.join(
+          _dartSdkPath(_cache), 'bin', 'snapshots',
+          _artifactToFileName(artifact),
+        );
       case Artifact.flutterTester:
       case Artifact.vmSnapshotData:
       case Artifact.isolateSnapshotData:
-      case Artifact.frontendServerSnapshotForEngineDartSdk:
       case Artifact.icuData:
         final String engineArtifactsPath = _cache.getArtifactDirectory('engine').path;
         final String platformDirName = _enginePlatformDirectoryName(platform);
@@ -795,7 +797,7 @@ class CachedLocalEngineArtifacts implements LocalEngineArtifacts {
         final String path = _fileSystem.path.join(_hostEngineOutPath, 'dart-sdk', 'bin', 'snapshots', _hostArtifactToFileName(artifact, _platform.isWindows));
         return _fileSystem.file(path);
       case HostArtifact.dartdevcSnapshot:
-        final String path = _fileSystem.path.join(_dartSdkPath(_fileSystem), 'bin', 'snapshots', _hostArtifactToFileName(artifact, _platform.isWindows));
+        final String path = _fileSystem.path.join(_dartSdkPath(_cache), 'bin', 'snapshots', _hostArtifactToFileName(artifact, _platform.isWindows));
         return _fileSystem.file(path);
       case HostArtifact.kernelWorkerSnapshot:
         final String path = _fileSystem.path.join(_hostEngineOutPath, 'dart-sdk', 'bin', 'snapshots', _hostArtifactToFileName(artifact, _platform.isWindows));
@@ -920,7 +922,9 @@ class CachedLocalEngineArtifacts implements LocalEngineArtifacts {
       case Artifact.windowsUwpCppClientWrapper:
         return _fileSystem.path.join(_hostEngineOutPath, artifactFileName);
       case Artifact.frontendServerSnapshotForEngineDartSdk:
-        return _fileSystem.path.join(_hostEngineOutPath, 'gen', artifactFileName);
+        return _fileSystem.path.join(
+          _hostEngineOutPath, 'dart-sdk', 'bin', 'snapshots', artifactFileName,
+        );
       case Artifact.uwptool:
         return _fileSystem.path.join(_hostEngineOutPath, artifactFileName);
     }
@@ -1030,8 +1034,8 @@ class OverrideArtifacts implements Artifacts {
 }
 
 /// Locate the Dart SDK.
-String _dartSdkPath(FileSystem fileSystem) {
-  return fileSystem.path.join(Cache.flutterRoot!, 'bin', 'cache', 'dart-sdk');
+String _dartSdkPath(Cache cache) {
+  return cache.getRoot().childDirectory('dart-sdk').path;
 }
 
 class _TestArtifacts implements Artifacts {

packages/flutter_tools/test/general.shard/artifacts_test.dart

@@ -129,6 +129,10 @@ void main() {
         artifacts.getArtifactPath(Artifact.windowsUwpDesktopPath, platform: TargetPlatform.windows_uwp_x64, mode: BuildMode.release),
         fileSystem.path.join('root', 'bin', 'cache', 'artifacts', 'engine', 'windows-uwp-x64-release'),
       );
+      expect(
+        artifacts.getArtifactPath(Artifact.frontendServerSnapshotForEngineDartSdk),
+        fileSystem.path.join('root', 'bin', 'cache', 'dart-sdk', 'bin', 'snapshots', 'frontend_server.dart.snapshot')
+      );
     });
 
     testWithoutContext('precompiled web artifact paths are correct', () {
@@ -294,6 +298,11 @@ void main() {
         artifacts.getHostArtifact(HostArtifact.engineDartSdkPath).path,
         fileSystem.path.join('/out', 'host_debug_unopt', 'dart-sdk'),
       );
+      expect(
+        artifacts.getArtifactPath(Artifact.frontendServerSnapshotForEngineDartSdk),
+        fileSystem.path.join('/out', 'host_debug_unopt', 'dart-sdk', 'bin',
+          'snapshots', 'frontend_server.dart.snapshot')
+      );
     });
 
     testWithoutContext('getEngineType', () {