From 89692884a1ac0077a1d62917e22a5d5e4383b9d9 Mon Sep 17 00:00:00 2001
From: Christopher Fujino <christopherfujino@gmail.com>
Date: Tue, 7 Nov 2023 17:53:22 -0800
Subject: [PATCH] [flutter_tools] Fix local engine preview device (#138046)

Fixes https://github.com/flutter/flutter/issues/137982
---
 packages/flutter_tools/lib/src/artifacts.dart             | 7 ++++++-
 .../flutter_tools/test/general.shard/artifacts_test.dart  | 8 ++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/packages/flutter_tools/lib/src/artifacts.dart b/packages/flutter_tools/lib/src/artifacts.dart
index 7f3e6abaeeba1..7b70f107a6226 100644
--- a/packages/flutter_tools/lib/src/artifacts.dart
+++ b/packages/flutter_tools/lib/src/artifacts.dart
@@ -1028,7 +1028,12 @@ class CachedLocalEngineArtifacts implements Artifacts {
       case Artifact.flutterToolsFileGenerators:
         return _getFileGeneratorsPath();
       case Artifact.flutterPreviewDevice:
-        throw UnimplementedError('The preview device is not supported with local engine builds');
+        return _backupCache.getArtifactPath(
+          artifact,
+          platform: platform,
+          mode: mode,
+          environmentType: environmentType,
+        );
     }
   }
 
diff --git a/packages/flutter_tools/test/general.shard/artifacts_test.dart b/packages/flutter_tools/test/general.shard/artifacts_test.dart
index dc39ffe002c8c..bb0915c25ddda 100644
--- a/packages/flutter_tools/test/general.shard/artifacts_test.dart
+++ b/packages/flutter_tools/test/general.shard/artifacts_test.dart
@@ -329,6 +329,14 @@ void main() {
           'snapshots', 'frontend_server_aot.dart.snapshot')
       );
 
+      expect(
+        artifacts.getArtifactPath(
+          Artifact.flutterPreviewDevice,
+          platform: TargetPlatform.windows_x64,
+        ),
+        fileSystem.path.join('root', 'bin', 'cache', 'artifacts',
+          'flutter_preview', 'flutter_preview.exe'),
+      );
 
       fileSystem.file(fileSystem.path.join('/out', 'host_debug_unopt', 'impellerc'))
         .createSync(recursive: true);