From 8dc5ece999d257bbf68c451bc34ed57fe16dfffa Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Wed, 18 Sep 2024 15:52:11 -0700
Subject: [PATCH 01/22] Adds vscode workspace with impeller test runner

---
 .gitignore              |   1 -
 .vscode/extensions.json |  17 ----
 engine.code-workspace   | 197 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 197 insertions(+), 18 deletions(-)
 delete mode 100644 .vscode/extensions.json
 create mode 100644 engine.code-workspace

diff --git a/.gitignore b/.gitignore
index 57696b6cdc409..9abe6831d2794 100644
--- a/.gitignore
+++ b/.gitignore
@@ -49,7 +49,6 @@ xcuserdata
 .project
 .settings/
 .vscode/
-!.vscode/extensions.json
 
 # packages file containing multi-root paths
 .packages.generated
diff --git a/.vscode/extensions.json b/.vscode/extensions.json
deleted file mode 100644
index 314960ffa5d1b..0000000000000
--- a/.vscode/extensions.json
+++ /dev/null
@@ -1,17 +0,0 @@
-{
-  "recommendations": [
-    // Uses github-styled markdown preview, which supports more features than the default markdown preview.
-    "bierner.github-markdown-preview",
-
-    // Flutter and Dart extensions.
-    "Dart-Code.dart-code",
-
-    // Supports C/C++ in the engine.
-    // See https://github.com/flutter/engine/blob/main/docs/contributing/Setting-up-the-Engine-development-environment.md#vscode-with-cc-intellisense-cc
-    "llvm-vs-code-extensions.vscode-clangd",
-
-    // Auto-formats C/C++ code.
-    // https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#cc
-    "xaver.clang-format",
-  ]
-}
diff --git a/engine.code-workspace b/engine.code-workspace
new file mode 100644
index 0000000000000..026fde0433c74
--- /dev/null
+++ b/engine.code-workspace
@@ -0,0 +1,197 @@
+{
+  "folders": [
+    {
+      "path": "."
+    }
+  ],
+  "settings": {
+    "files.associations": {
+      "optional": "cpp",
+      "__bit_reference": "cpp",
+      "__bits": "cpp",
+      "__config": "cpp",
+      "__debug": "cpp",
+      "__errc": "cpp",
+      "__hash_table": "cpp",
+      "__locale": "cpp",
+      "__mutex_base": "cpp",
+      "__node_handle": "cpp",
+      "__nullptr": "cpp",
+      "__split_buffer": "cpp",
+      "__string": "cpp",
+      "__threading_support": "cpp",
+      "__tree": "cpp",
+      "__tuple": "cpp",
+      "any": "cpp",
+      "array": "cpp",
+      "atomic": "cpp",
+      "bitset": "cpp",
+      "cctype": "cpp",
+      "chrono": "cpp",
+      "cinttypes": "cpp",
+      "clocale": "cpp",
+      "cmath": "cpp",
+      "codecvt": "cpp",
+      "compare": "cpp",
+      "complex": "cpp",
+      "concepts": "cpp",
+      "condition_variable": "cpp",
+      "csignal": "cpp",
+      "cstdarg": "cpp",
+      "cstddef": "cpp",
+      "cstdint": "cpp",
+      "cstdio": "cpp",
+      "cstdlib": "cpp",
+      "cstring": "cpp",
+      "ctime": "cpp",
+      "cwchar": "cpp",
+      "cwctype": "cpp",
+      "deque": "cpp",
+      "exception": "cpp",
+      "forward_list": "cpp",
+      "fstream": "cpp",
+      "future": "cpp",
+      "initializer_list": "cpp",
+      "iomanip": "cpp",
+      "ios": "cpp",
+      "iosfwd": "cpp",
+      "iostream": "cpp",
+      "istream": "cpp",
+      "limits": "cpp",
+      "list": "cpp",
+      "locale": "cpp",
+      "map": "cpp",
+      "memory": "cpp",
+      "mutex": "cpp",
+      "new": "cpp",
+      "numeric": "cpp",
+      "ostream": "cpp",
+      "queue": "cpp",
+      "random": "cpp",
+      "ratio": "cpp",
+      "regex": "cpp",
+      "set": "cpp",
+      "span": "cpp",
+      "sstream": "cpp",
+      "stack": "cpp",
+      "stdexcept": "cpp",
+      "streambuf": "cpp",
+      "string": "cpp",
+      "string_view": "cpp",
+      "strstream": "cpp",
+      "system_error": "cpp",
+      "tuple": "cpp",
+      "type_traits": "cpp",
+      "typeinfo": "cpp",
+      "unordered_map": "cpp",
+      "unordered_set": "cpp",
+      "valarray": "cpp",
+      "variant": "cpp",
+      "vector": "cpp",
+      "algorithm": "cpp",
+      "filesystem": "cpp",
+      "memory_resource": "cpp",
+      "bit": "cpp",
+      "charconv": "cpp",
+      "format": "cpp",
+      "functional": "cpp",
+      "iterator": "cpp",
+      "utility": "cpp",
+      "__assert": "cpp",
+      "*.inc": "cpp",
+      "__verbose_abort": "cpp",
+      "*.def": "cpp",
+      "*.hpp11": "cpp",
+      "__functional_base": "cpp",
+      "shared_mutex": "cpp",
+      "coroutine": "cpp",
+      "hash_map": "cpp",
+      "hash_set": "cpp",
+      "thread": "cpp",
+      "propagate_const": "cpp",
+      "*.gen": "cpp",
+      "simd": "cpp",
+      "barrier": "cpp",
+      "cuchar": "cpp",
+      "latch": "cpp",
+      "numbers": "cpp",
+      "scoped_allocator": "cpp",
+      "semaphore": "cpp",
+      "typeindex": "cpp",
+      "__std_stream": "cpp",
+      "*.ipp": "cpp",
+      "csetjmp": "cpp",
+      "cfenv": "cpp"
+    },
+    "C_Cpp.default.includePath": [
+      "${default}",
+      "${workspaceFolder}/..",
+      "${workspaceFolder}",
+    ],
+    "dotnet.defaultSolution": "disable",
+    "dart.showTodos": false,
+    "testMate.cpp.test.advancedExecutables": [
+      {
+        "pattern": "../out/host_debug_unopt_arm64/impeller_unittests",
+        "runTask": {
+          "before": [
+            "impeller_unittests_arm64"
+          ]
+        },
+        "gtest": {
+          "prependTestRunningArgs": [
+            "--enable_playground"
+          ]
+        }
+      }
+    ],
+  },
+  "tasks": {
+    "version": "2.0.0",
+    "tasks": [
+      {
+        "label": "impeller_unittests_arm64",
+        "type": "shell",
+        "command": "./flutter/bin/et",
+        "args": [
+          "build",
+          "-c",
+          "host_debug_unopt_arm64",
+          "//flutter/impeller:impeller_unittests"
+        ],
+        "options": {
+          "cwd": "${workspaceFolder}/.."
+        },
+        "problemMatcher": [
+          "$gcc"
+        ],
+        "presentation": {
+          "echo": true,
+          "reveal": "always",
+          "focus": false,
+          "panel": "shared",
+          "clear": true
+        },
+        "group": {
+          "kind": "build",
+        }
+      }
+    ]
+  },
+  "extensions": {
+    "recommendations": [
+      // C++ TestMate
+      "matepek.vscode-catch2-test-adapter",
+      // Uses github-styled markdown preview, which supports more features than the default markdown preview.
+      "bierner.github-markdown-preview",
+      // Flutter and Dart extensions.
+      "Dart-Code.dart-code",
+      // Supports C/C++ in the engine.
+      // See https://github.com/flutter/engine/blob/main/docs/contributing/Setting-up-the-Engine-development-environment.md#vscode-with-cc-intellisense-cc
+      "llvm-vs-code-extensions.vscode-clangd",
+      // Auto-formats C/C++ code.
+      // https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#cc
+      "xaver.clang-format",
+    ]
+  }
+}

From a1ec843cccb8854318b54e859753bfe0da9aa224 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Wed, 18 Sep 2024 16:09:22 -0700
Subject: [PATCH 02/22] not sure why, but these have to be named like this
 which will interfere with linux

---
 engine.code-workspace | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/engine.code-workspace b/engine.code-workspace
index 026fde0433c74..9298159472958 100644
--- a/engine.code-workspace
+++ b/engine.code-workspace
@@ -135,7 +135,7 @@
         "pattern": "../out/host_debug_unopt_arm64/impeller_unittests",
         "runTask": {
           "before": [
-            "impeller_unittests_arm64"
+            "impeller_unittests"
           ]
         },
         "gtest": {
@@ -150,7 +150,7 @@
     "version": "2.0.0",
     "tasks": [
       {
-        "label": "impeller_unittests_arm64",
+        "label": "impeller_unittests",
         "type": "shell",
         "command": "./flutter/bin/et",
         "args": [
@@ -194,4 +194,4 @@
       "xaver.clang-format",
     ]
   }
-}
+}
\ No newline at end of file

From 86c084d4b9aac2a81bda2de9e01bcd49c1da5156 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Wed, 18 Sep 2024 16:16:16 -0700
Subject: [PATCH 03/22] added my launch entry too for debugging

---
 engine.code-workspace | 32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/engine.code-workspace b/engine.code-workspace
index 9298159472958..6c92d331fa88b 100644
--- a/engine.code-workspace
+++ b/engine.code-workspace
@@ -135,7 +135,7 @@
         "pattern": "../out/host_debug_unopt_arm64/impeller_unittests",
         "runTask": {
           "before": [
-            "impeller_unittests"
+            "impeller_unittests_arm64"
           ]
         },
         "gtest": {
@@ -150,7 +150,7 @@
     "version": "2.0.0",
     "tasks": [
       {
-        "label": "impeller_unittests",
+        "label": "impeller_unittests_arm64",
         "type": "shell",
         "command": "./flutter/bin/et",
         "args": [
@@ -193,5 +193,33 @@
       // https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#cc
       "xaver.clang-format",
     ]
+  },
+  "launch": {
+    "version": "0.2.0",
+    "configurations": [
+      {
+        "name": "impeller_unittests_arm64",
+        "type": "cppdbg",
+        "request": "launch",
+        "program": "${workspaceFolder}/../out/host_debug_unopt_arm64/impeller_unittests",
+        "args": [
+          "--enable_playground",
+        ],
+        "stopAtEntry": false,
+        "cwd": "${workspaceFolder}/../out/host_debug_unopt_arm64",
+        "environment": [],
+        "externalConsole": false,
+        "MIMode": "lldb",
+        "setupCommands": [
+          {
+            "description": "Enable pretty-printing for lldb",
+            "text": "settings set target.pretty-printing true",
+            "ignoreFailures": true
+          }
+        ],
+        "preLaunchTask": "impeller_unittests_arm64",
+      }
+    ],
+    "compounds": []
   }
 }
\ No newline at end of file

From 1148586cb181338c9c7d368632780f4ddcae9d7e Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Wed, 18 Sep 2024 16:19:06 -0700
Subject: [PATCH 04/22] added test adapter

---
 engine.code-workspace | 1 +
 1 file changed, 1 insertion(+)

diff --git a/engine.code-workspace b/engine.code-workspace
index 6c92d331fa88b..e7963affe7519 100644
--- a/engine.code-workspace
+++ b/engine.code-workspace
@@ -132,6 +132,7 @@
     "dart.showTodos": false,
     "testMate.cpp.test.advancedExecutables": [
       {
+        "name": "impeller_unittests_arm64",
         "pattern": "../out/host_debug_unopt_arm64/impeller_unittests",
         "runTask": {
           "before": [

From 7f07717aa44c781b975b3b8af80804acd76250af Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Wed, 18 Sep 2024 16:30:02 -0700
Subject: [PATCH 05/22] added source map for the debugger - works from launch
 ui, not from debug test ui =(

---
 engine.code-workspace | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/engine.code-workspace b/engine.code-workspace
index e7963affe7519..8946ff3a11d08 100644
--- a/engine.code-workspace
+++ b/engine.code-workspace
@@ -216,6 +216,11 @@
             "description": "Enable pretty-printing for lldb",
             "text": "settings set target.pretty-printing true",
             "ignoreFailures": true
+          },
+          {
+            "description": "Source map",
+            "text": "settings set target.source-map \"flutter/\" \"${workspaceFolder}\"",
+            "ignoreFailures": false
           }
         ],
         "preLaunchTask": "impeller_unittests_arm64",

From 1a4a2a1d51cc503fff5d1b61fa8edab94b77d32c Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Wed, 18 Sep 2024 16:51:16 -0700
Subject: [PATCH 06/22] got source map working for the test menu

---
 engine.code-workspace | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/engine.code-workspace b/engine.code-workspace
index 8946ff3a11d08..ae76943d85172 100644
--- a/engine.code-workspace
+++ b/engine.code-workspace
@@ -146,6 +146,33 @@
         }
       }
     ],
+    "testMate.cpp.debug.configTemplate": {
+      "type": "cppvsdbg",
+      "linux": {
+        "type": "cppdbg",
+        "MIMode": "gdb"
+      },
+      "darwin": {
+        "type": "cppdbg",
+        "MIMode": "lldb",
+        "setupCommands": [
+          {
+            "description": "Source map",
+            "text": "settings set target.source-map \"flutter/\" \"${workspaceFolder}\"",
+            "ignoreFailures": false
+          }
+        ],
+      },
+      "win32": {
+        "type": "cppvsdbg"
+      },
+      "program": "${exec}",
+      "args": "${argsArray}",
+      "cwd": "${cwd}",
+      "env": "${envObj}",
+      "environment": "${envObjArray}",
+      "sourceFileMap": "${sourceFileMapObj}",
+    }
   },
   "tasks": {
     "version": "2.0.0",

From 8f0f017706c98bb1dcd4e09ce9c12d546a744712 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 09:44:56 -0700
Subject: [PATCH 07/22] license update

---
 ci/licenses_golden/excluded_files | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ci/licenses_golden/excluded_files b/ci/licenses_golden/excluded_files
index 549608f4d5a5e..56b935eea2ae8 100644
--- a/ci/licenses_golden/excluded_files
+++ b/ci/licenses_golden/excluded_files
@@ -18,7 +18,6 @@
 ../../../flutter/.github
 ../../../flutter/.gitignore
 ../../../flutter/.style.yapf
-../../../flutter/.vscode
 ../../../flutter/AUTHORS
 ../../../flutter/CODEOWNERS
 ../../../flutter/CONTRIBUTING.md
@@ -50,6 +49,7 @@
 ../../../flutter/display_list/utils/dl_accumulation_rect_unittests.cc
 ../../../flutter/display_list/utils/dl_matrix_clip_tracker_unittests.cc
 ../../../flutter/docs
+../../../flutter/engine.code-workspace
 ../../../flutter/examples
 ../../../flutter/flow/README.md
 ../../../flutter/flow/diff_context_unittests.cc

From aa24e2fd9df5b62575c971fcca72737109a5947b Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Fri, 20 Sep 2024 09:06:05 -0700
Subject: [PATCH 08/22] license exception

---
 tools/licenses/lib/paths.dart | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/licenses/lib/paths.dart b/tools/licenses/lib/paths.dart
index d2f2b93306c4f..35d17f3c676fd 100644
--- a/tools/licenses/lib/paths.dart
+++ b/tools/licenses/lib/paths.dart
@@ -25,6 +25,7 @@ final Set<String> skippedPaths = <String>{
   r'flutter/buildtools', // only used by build
   r'flutter/ci',
   r'flutter/docs',
+  r'flutter/engine.code-workspace',
   r'flutter/flutter_frontend_server',
   r'flutter/impeller/docs',
   r'flutter/lib/web_ui/build', // this is compiler-generated output

From d4fcdeb90d6c05bcb1818db420b608692d116cf4 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Fri, 20 Sep 2024 09:30:16 -0700
Subject: [PATCH 09/22] tool signature

---
 ci/licenses_golden/tool_signature | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ci/licenses_golden/tool_signature b/ci/licenses_golden/tool_signature
index 22136f5b4a8a1..4cc7ffd679d25 100644
--- a/ci/licenses_golden/tool_signature
+++ b/ci/licenses_golden/tool_signature
@@ -1,2 +1,2 @@
-Signature: 53025d1261891c38c7bccb158862e09f
+Signature: 8859e172e060ecb45aa665c3119d5d25
 

From 3c37b7c0a518c5ad1899da1b63d5bb5f824085fc Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 10:58:29 -0700
Subject: [PATCH 10/22] Added tool for updating the workspace

---
 tools/json_injector/README.md                 |  0
 tools/json_injector/bin/main.dart             |  5 ++
 tools/json_injector/lib/json_injector.dart    | 22 ++++++
 tools/json_injector/pubspec.yaml              |  5 ++
 .../test/json_injector_test.dart              | 79 +++++++++++++++++++
 5 files changed, 111 insertions(+)
 create mode 100644 tools/json_injector/README.md
 create mode 100644 tools/json_injector/bin/main.dart
 create mode 100644 tools/json_injector/lib/json_injector.dart
 create mode 100644 tools/json_injector/pubspec.yaml
 create mode 100644 tools/json_injector/test/json_injector_test.dart

diff --git a/tools/json_injector/README.md b/tools/json_injector/README.md
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/tools/json_injector/bin/main.dart b/tools/json_injector/bin/main.dart
new file mode 100644
index 0000000000000..93a23ee210a86
--- /dev/null
+++ b/tools/json_injector/bin/main.dart
@@ -0,0 +1,5 @@
+import 'package:json_injector/json_injector.dart';
+
+void main() {
+  
+}
\ No newline at end of file
diff --git a/tools/json_injector/lib/json_injector.dart b/tools/json_injector/lib/json_injector.dart
new file mode 100644
index 0000000000000..60f9b351d411c
--- /dev/null
+++ b/tools/json_injector/lib/json_injector.dart
@@ -0,0 +1,22 @@
+import 'dart:convert' show jsonDecode;
+
+Object? inject(Object? json, Object? injector) {
+  if (json is Map && injector is Map) {
+    final result = <dynamic, dynamic>{};
+    for (final key in json.keys) {
+      if (!injector.containsKey(key)) {
+        result[key] = json[key];
+      }
+    }
+    for (final key in injector.keys) {
+      if (json.containsKey(key)) {
+        result[key] = inject(json[key], injector[key]);
+      } else {
+        result[key] = injector[key];
+      }
+    }
+    return result;
+  }
+
+  return json;
+}
diff --git a/tools/json_injector/pubspec.yaml b/tools/json_injector/pubspec.yaml
new file mode 100644
index 0000000000000..b5c270ad23936
--- /dev/null
+++ b/tools/json_injector/pubspec.yaml
@@ -0,0 +1,5 @@
+name: json_injector
+environment:
+  sdk: '^3.6.0-255.0.dev'
+dependencies:
+  test: any
diff --git a/tools/json_injector/test/json_injector_test.dart b/tools/json_injector/test/json_injector_test.dart
new file mode 100644
index 0000000000000..f5d8e16d3ef19
--- /dev/null
+++ b/tools/json_injector/test/json_injector_test.dart
@@ -0,0 +1,79 @@
+import 'package:json_injector/json_injector.dart';
+import 'package:test/test.dart';
+
+bool _deepEquals(Object? x, Object? y) {
+  if (x is Map && y is Map) {
+    if (x.length != y.length) {
+      return false;
+    }
+
+    for (final key in x.keys) {
+      if (!_deepEquals(x[key], y[key])) {
+        return false;
+      }
+    }
+    return true;
+  } else if (x is List && y is List) {
+    if (x.length != y.length) {
+      return false;
+    }
+
+    for (int i = 0; i < x.length; i++) {
+      if (_deepEquals(x[i], y[i])) {
+        return false;
+      }
+    }
+    return true;
+  } else {
+    return x == y;
+  }
+}
+
+void main() {
+  test('noop', () {
+    const json = {
+      'configurations': <Object?>[],
+    };
+    final result = inject(json, {});
+
+    expect(_deepEquals(json, result), isTrue);
+  });
+
+  test('simple inject', () {
+    const json = {
+      'configurations': <Object?>[],
+    };
+    const injector = {
+      'bar': <Object?>[],
+    };
+
+    expect(
+        _deepEquals(inject(json, injector), {
+          'configurations': <Object?>[],
+          'bar': <Object?>[],
+        }),
+        isTrue);
+  });
+
+  test('simple recurse', () {
+    const json = {
+      'configurations': {
+        'foo': 1,
+      },
+    };
+    const injector = {
+      'configurations': {
+        'bar': 2,
+      },
+    };
+
+    expect(
+        _deepEquals(inject(json, injector), {
+          'configurations': {
+            'foo': 1,
+            'bar': 2,
+          },
+        }),
+        isTrue);
+  });
+}

From 0d5ae0b5218fc8a281d049c1c82aa673a5903e39 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 11:05:51 -0700
Subject: [PATCH 11/22] added matcher

---
 .../test/json_injector_test.dart              | 34 ++++++++++++++-----
 1 file changed, 26 insertions(+), 8 deletions(-)

diff --git a/tools/json_injector/test/json_injector_test.dart b/tools/json_injector/test/json_injector_test.dart
index f5d8e16d3ef19..44919c2eb2534 100644
--- a/tools/json_injector/test/json_injector_test.dart
+++ b/tools/json_injector/test/json_injector_test.dart
@@ -1,7 +1,7 @@
 import 'package:json_injector/json_injector.dart';
 import 'package:test/test.dart';
 
-bool _deepEquals(Object? x, Object? y) {
+bool _deepEquals(dynamic x, dynamic y) {
   if (x is Map && y is Map) {
     if (x.length != y.length) {
       return false;
@@ -29,6 +29,24 @@ bool _deepEquals(Object? x, Object? y) {
   }
 }
 
+class _DeepMatcher extends Matcher {
+  _DeepMatcher(this._target);
+
+  final dynamic _target;
+
+  @override
+  Description describe(Description description) {
+    description.add('equals $_target');
+    return description;
+  }
+
+  @override
+  bool matches(dynamic item, Map<dynamic, dynamic> matchState) =>
+      _deepEquals(item, _target);
+}
+
+Matcher _isDeepEquals(dynamic x) => _DeepMatcher(x);
+
 void main() {
   test('noop', () {
     const json = {
@@ -36,7 +54,7 @@ void main() {
     };
     final result = inject(json, {});
 
-    expect(_deepEquals(json, result), isTrue);
+    expect(result, _isDeepEquals(json));
   });
 
   test('simple inject', () {
@@ -48,11 +66,11 @@ void main() {
     };
 
     expect(
-        _deepEquals(inject(json, injector), {
+        inject(json, injector),
+        _isDeepEquals({
           'configurations': <Object?>[],
           'bar': <Object?>[],
-        }),
-        isTrue);
+        }));
   });
 
   test('simple recurse', () {
@@ -68,12 +86,12 @@ void main() {
     };
 
     expect(
-        _deepEquals(inject(json, injector), {
+        inject(json, injector),
+        _isDeepEquals({
           'configurations': {
             'foo': 1,
             'bar': 2,
           },
-        }),
-        isTrue);
+        }));
   });
 }

From 1eafab42fa5e5c99d219dbf813dd8cae8fa0ea03 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 11:32:09 -0700
Subject: [PATCH 12/22] added list

---
 tools/json_injector/lib/json_injector.dart    | 11 +++++++++
 .../test/json_injector_test.dart              | 23 ++++++++++++++++++-
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/tools/json_injector/lib/json_injector.dart b/tools/json_injector/lib/json_injector.dart
index 60f9b351d411c..c6e50079930f1 100644
--- a/tools/json_injector/lib/json_injector.dart
+++ b/tools/json_injector/lib/json_injector.dart
@@ -16,6 +16,17 @@ Object? inject(Object? json, Object? injector) {
       }
     }
     return result;
+  } if (json is List<Map> && injector is List<Map>) {
+    final Map<String, Object?> jsonList = {};
+    final Map<String, Object?> injectorList = {};
+    for (final item in json) {
+      jsonList['name'] = item;
+    }
+    for (final item in injector) {
+      injectorList['name'] = item;
+    }
+    final joined = inject(jsonList, injectorList) as Map?;
+    return joined?.values.toList();
   }
 
   return json;
diff --git a/tools/json_injector/test/json_injector_test.dart b/tools/json_injector/test/json_injector_test.dart
index 44919c2eb2534..74e91775f0bf8 100644
--- a/tools/json_injector/test/json_injector_test.dart
+++ b/tools/json_injector/test/json_injector_test.dart
@@ -19,7 +19,7 @@ bool _deepEquals(dynamic x, dynamic y) {
     }
 
     for (int i = 0; i < x.length; i++) {
-      if (_deepEquals(x[i], y[i])) {
+      if (!_deepEquals(x[i], y[i])) {
         return false;
       }
     }
@@ -94,4 +94,25 @@ void main() {
           },
         }));
   });
+
+  test('simple list', () {
+    const json = {
+      'configurations': [
+        {'name': 'foo', 'x': 1},
+      ],
+    };
+    const injector = {
+      'configurations': [
+        {'name': 'foo', 'y': 1},
+      ],
+    };
+
+    expect(
+        inject(json, injector),
+        _isDeepEquals({
+          'configurations': [
+            {'name': 'foo', 'x': 1, 'y': 1},
+          ],
+        }));
+  });
 }

From dc74f17df6243497bf531c678e5af859469cb449 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 11:35:21 -0700
Subject: [PATCH 13/22] pulled out namekey

---
 tools/json_injector/lib/json_injector.dart       | 14 ++++++--------
 tools/json_injector/test/json_injector_test.dart |  2 +-
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/tools/json_injector/lib/json_injector.dart b/tools/json_injector/lib/json_injector.dart
index c6e50079930f1..dc7bd6c3a7fe3 100644
--- a/tools/json_injector/lib/json_injector.dart
+++ b/tools/json_injector/lib/json_injector.dart
@@ -1,6 +1,4 @@
-import 'dart:convert' show jsonDecode;
-
-Object? inject(Object? json, Object? injector) {
+Object? inject(Object? json, Object? injector, {String? nameKey}) {
   if (json is Map && injector is Map) {
     final result = <dynamic, dynamic>{};
     for (final key in json.keys) {
@@ -10,22 +8,22 @@ Object? inject(Object? json, Object? injector) {
     }
     for (final key in injector.keys) {
       if (json.containsKey(key)) {
-        result[key] = inject(json[key], injector[key]);
+        result[key] = inject(json[key], injector[key], nameKey: nameKey);
       } else {
         result[key] = injector[key];
       }
     }
     return result;
-  } if (json is List<Map> && injector is List<Map>) {
+  } if (json is List<Map> && injector is List<Map> && nameKey != null) {
     final Map<String, Object?> jsonList = {};
     final Map<String, Object?> injectorList = {};
     for (final item in json) {
-      jsonList['name'] = item;
+      jsonList[nameKey] = item;
     }
     for (final item in injector) {
-      injectorList['name'] = item;
+      injectorList[nameKey] = item;
     }
-    final joined = inject(jsonList, injectorList) as Map?;
+    final joined = inject(jsonList, injectorList, nameKey: nameKey) as Map?;
     return joined?.values.toList();
   }
 
diff --git a/tools/json_injector/test/json_injector_test.dart b/tools/json_injector/test/json_injector_test.dart
index 74e91775f0bf8..25f60bb384005 100644
--- a/tools/json_injector/test/json_injector_test.dart
+++ b/tools/json_injector/test/json_injector_test.dart
@@ -108,7 +108,7 @@ void main() {
     };
 
     expect(
-        inject(json, injector),
+        inject(json, injector, nameKey: 'name'),
         _isDeepEquals({
           'configurations': [
             {'name': 'foo', 'x': 1, 'y': 1},

From 1e8a0b91a74aed518763ceaf7aa9bbe05391b8d6 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 13:35:31 -0700
Subject: [PATCH 14/22] added simple template example

---
 tools/json_injector/bin/main.dart             |  6 +++-
 tools/json_injector/lib/json_injector.dart    | 29 +++++++++++++++----
 .../test/json_injector_test.dart              | 28 ++++++++++++++++++
 3 files changed, 57 insertions(+), 6 deletions(-)

diff --git a/tools/json_injector/bin/main.dart b/tools/json_injector/bin/main.dart
index 93a23ee210a86..7699c509c3a4e 100644
--- a/tools/json_injector/bin/main.dart
+++ b/tools/json_injector/bin/main.dart
@@ -1,5 +1,9 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
 import 'package:json_injector/json_injector.dart';
 
 void main() {
-  
+
 }
\ No newline at end of file
diff --git a/tools/json_injector/lib/json_injector.dart b/tools/json_injector/lib/json_injector.dart
index dc7bd6c3a7fe3..f37d90601a2d7 100644
--- a/tools/json_injector/lib/json_injector.dart
+++ b/tools/json_injector/lib/json_injector.dart
@@ -1,4 +1,13 @@
-Object? inject(Object? json, Object? injector, {String? nameKey}) {
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const String _templateKey = 'json_injector:template';
+
+Object? inject(Object? json, Object? injector,
+    {String? nameKey, Map<String, Map<dynamic, dynamic>>? templates}) {
+  Object? recurse(Object? x, Object? y) =>
+      inject(x, y, nameKey: nameKey, templates: templates);
   if (json is Map && injector is Map) {
     final result = <dynamic, dynamic>{};
     for (final key in json.keys) {
@@ -7,14 +16,24 @@ Object? inject(Object? json, Object? injector, {String? nameKey}) {
       }
     }
     for (final key in injector.keys) {
-      if (json.containsKey(key)) {
-        result[key] = inject(json[key], injector[key], nameKey: nameKey);
+      if (key == _templateKey) {
+        final String templateName = injector[key] as String;
+        final Map<dynamic, dynamic>? template = templates?[templateName];
+        if (template == null) {
+          throw StateError('unknown template: $templateName');
+        }
+        for (final templateKey in template.keys) {
+          result[templateKey] = template[templateKey];
+        }
+      } else if (json.containsKey(key)) {
+        result[key] = recurse(json[key], injector[key]);
       } else {
         result[key] = injector[key];
       }
     }
     return result;
-  } if (json is List<Map> && injector is List<Map> && nameKey != null) {
+  }
+  if (json is List<Map> && injector is List<Map> && nameKey != null) {
     final Map<String, Object?> jsonList = {};
     final Map<String, Object?> injectorList = {};
     for (final item in json) {
@@ -23,7 +42,7 @@ Object? inject(Object? json, Object? injector, {String? nameKey}) {
     for (final item in injector) {
       injectorList[nameKey] = item;
     }
-    final joined = inject(jsonList, injectorList, nameKey: nameKey) as Map?;
+    final joined = recurse(jsonList, injectorList) as Map?;
     return joined?.values.toList();
   }
 
diff --git a/tools/json_injector/test/json_injector_test.dart b/tools/json_injector/test/json_injector_test.dart
index 25f60bb384005..e260d15dcb596 100644
--- a/tools/json_injector/test/json_injector_test.dart
+++ b/tools/json_injector/test/json_injector_test.dart
@@ -1,3 +1,7 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
 import 'package:json_injector/json_injector.dart';
 import 'package:test/test.dart';
 
@@ -115,4 +119,28 @@ void main() {
           ],
         }));
   });
+
+  test('simple template', () {
+    const json = {
+      'configurations': [
+        {'name': 'foo', 'x': 1},
+      ],
+    };
+    const injector = {
+      'configurations': [
+        {'name': 'foo', 'json_injector:template': 'super'},
+      ],
+    };
+    const templates = {
+      'super': {'y': 2, 'z': 3}
+    };
+
+    expect(
+        inject(json, injector, nameKey: 'name', templates: templates),
+        _isDeepEquals({
+          'configurations': [
+            {'name': 'foo', 'x': 1, 'y': 2, 'z': 3},
+          ],
+        }));
+  });
 }

From c37888cdb805308a887654f195248cad2624d25c Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 13:53:25 -0700
Subject: [PATCH 15/22] implemented main

---
 tools/json_injector/bin/main.dart | 45 +++++++++++++++++++++++++++++--
 tools/json_injector/pubspec.yaml  |  1 +
 2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/tools/json_injector/bin/main.dart b/tools/json_injector/bin/main.dart
index 7699c509c3a4e..33954c38b49b8 100644
--- a/tools/json_injector/bin/main.dart
+++ b/tools/json_injector/bin/main.dart
@@ -2,8 +2,49 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'dart:convert' show jsonDecode, jsonEncode;
+import 'dart:io';
+
+import 'package:args/args.dart';
 import 'package:json_injector/json_injector.dart';
 
-void main() {
+void main(List<String> arguments) {
+  final parser = ArgParser()
+    ..addOption('input',
+        abbr: 'i', help: 'Path to the input JSON file', mandatory: true)
+    ..addOption('injector',
+        abbr: 'j', help: 'Path to the injector JSON file', mandatory: true)
+    ..addOption('output',
+        abbr: 'o', help: 'Path to the output JSON file', mandatory: true)
+    ..addOption('templates',
+        abbr: 't', help: 'Path to the templates JSON file', mandatory: false)
+    ..addOption('name-key',
+        abbr: 'n', help: 'Name key for processing', mandatory: false);
+
+  ArgResults argResults;
+  try {
+    argResults = parser.parse(arguments);
+  } catch (e) {
+    print('Error: $e\n');
+    print('Usage:\n${parser.usage}');
+    return;
+  }
+
+  final String inputJson = File(argResults['input'] as String).readAsStringSync();
+  final String injectorJson = File(argResults['injector'] as String).readAsStringSync();
+  final String? nameKey = argResults['name-key'] as String?;
+  final String outputPath = argResults['output'] as String;
+  
+  Map<String, Map<dynamic, dynamic>>? templates;
+  final String? templatesPath = argResults['templates'] as String?;
+  if (templatesPath != null) {
+    final templateJson = File(templatesPath).readAsStringSync();
+    templates = jsonDecode(templateJson) as Map<String, Map<dynamic, dynamic>>?;
+  }
+
+  final dynamic input = jsonDecode(inputJson);
+  final dynamic injector = jsonDecode(injectorJson);
 
-}
\ No newline at end of file
+  final dynamic result = inject(input, injector, nameKey: nameKey, templates: templates);
+  File(outputPath).writeAsStringSync(jsonEncode(result));
+}
diff --git a/tools/json_injector/pubspec.yaml b/tools/json_injector/pubspec.yaml
index b5c270ad23936..1d8ccbebc32ab 100644
--- a/tools/json_injector/pubspec.yaml
+++ b/tools/json_injector/pubspec.yaml
@@ -3,3 +3,4 @@ environment:
   sdk: '^3.6.0-255.0.dev'
 dependencies:
   test: any
+  args: any

From 68cc6ffb6b7ac8f97eb407b504dfe4779a8e7396 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 13:57:26 -0700
Subject: [PATCH 16/22] made error for missing mandatory options better

---
 tools/json_injector/bin/main.dart | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/tools/json_injector/bin/main.dart b/tools/json_injector/bin/main.dart
index 33954c38b49b8..524be77cdc753 100644
--- a/tools/json_injector/bin/main.dart
+++ b/tools/json_injector/bin/main.dart
@@ -21,20 +21,23 @@ void main(List<String> arguments) {
     ..addOption('name-key',
         abbr: 'n', help: 'Name key for processing', mandatory: false);
 
+  late final String inputJson;
+  late final String injectorJson;
+  late final String outputPath;
+
   ArgResults argResults;
   try {
     argResults = parser.parse(arguments);
+    inputJson = File(argResults['input'] as String).readAsStringSync();
+    injectorJson = File(argResults['injector'] as String).readAsStringSync();
+    outputPath = argResults['output'] as String;
   } catch (e) {
     print('Error: $e\n');
     print('Usage:\n${parser.usage}');
     return;
   }
 
-  final String inputJson = File(argResults['input'] as String).readAsStringSync();
-  final String injectorJson = File(argResults['injector'] as String).readAsStringSync();
   final String? nameKey = argResults['name-key'] as String?;
-  final String outputPath = argResults['output'] as String;
-  
   Map<String, Map<dynamic, dynamic>>? templates;
   final String? templatesPath = argResults['templates'] as String?;
   if (templatesPath != null) {
@@ -45,6 +48,7 @@ void main(List<String> arguments) {
   final dynamic input = jsonDecode(inputJson);
   final dynamic injector = jsonDecode(injectorJson);
 
-  final dynamic result = inject(input, injector, nameKey: nameKey, templates: templates);
+  final dynamic result =
+      inject(input, injector, nameKey: nameKey, templates: templates);
   File(outputPath).writeAsStringSync(jsonEncode(result));
 }

From 9a113bafcd8a6b75cf28f1daab14138b3f55c4a4 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 14:18:19 -0700
Subject: [PATCH 17/22] added injectos and cleaned up the workspace

---
 tools/json_injector/bin/main.dart             | 23 +++++++++---
 .../injectors/engine-templates.json           |  1 +
 .../injectors/engine.code-workspace           | 35 +++++++++++++++++++
 3 files changed, 55 insertions(+), 4 deletions(-)
 create mode 100644 tools/json_injector/injectors/engine-templates.json
 create mode 100644 tools/json_injector/injectors/engine.code-workspace

diff --git a/tools/json_injector/bin/main.dart b/tools/json_injector/bin/main.dart
index 524be77cdc753..fcdd5f63bb9a1 100644
--- a/tools/json_injector/bin/main.dart
+++ b/tools/json_injector/bin/main.dart
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:convert' show jsonDecode, jsonEncode;
+import 'dart:convert' show JsonEncoder, jsonDecode, jsonEncode;
 import 'dart:io';
 
 import 'package:args/args.dart';
@@ -45,10 +45,25 @@ void main(List<String> arguments) {
     templates = jsonDecode(templateJson) as Map<String, Map<dynamic, dynamic>>?;
   }
 
-  final dynamic input = jsonDecode(inputJson);
-  final dynamic injector = jsonDecode(injectorJson);
+  late final dynamic input;
+  try {
+    input = jsonDecode(inputJson);
+  } catch (ex) {
+    print('failed to parse: ${argResults['input']}');
+    print('Error: $ex');
+    return;
+  }
+  late final dynamic injector;
+  try {
+    injector = jsonDecode(injectorJson);
+  } catch (ex) {
+    print('failed to parse: ${argResults['injector']}');
+    print('Error: $ex');
+    return;
+  }
 
   final dynamic result =
       inject(input, injector, nameKey: nameKey, templates: templates);
-  File(outputPath).writeAsStringSync(jsonEncode(result));
+  File(outputPath)
+      .writeAsStringSync(const JsonEncoder.withIndent('  ').convert(result));
 }
diff --git a/tools/json_injector/injectors/engine-templates.json b/tools/json_injector/injectors/engine-templates.json
new file mode 100644
index 0000000000000..9e26dfeeb6e64
--- /dev/null
+++ b/tools/json_injector/injectors/engine-templates.json
@@ -0,0 +1 @@
+{}
\ No newline at end of file
diff --git a/tools/json_injector/injectors/engine.code-workspace b/tools/json_injector/injectors/engine.code-workspace
new file mode 100644
index 0000000000000..d29525fac3080
--- /dev/null
+++ b/tools/json_injector/injectors/engine.code-workspace
@@ -0,0 +1,35 @@
+{
+  "tasks": {
+    "version": "2.0.0",
+    "tasks": [
+      {
+        "label": "display_list_unittests_arm64",
+        "type": "shell",
+        "command": "./flutter/bin/et",
+        "args": [
+          "build",
+          "-c",
+          "host_debug_unopt_arm64",
+          "//flutter/display_list:display_list_unittests"
+        ],
+        "options": {
+          "cwd": "${workspaceFolder}/.."
+        },
+        "problemMatcher": [
+          "$gcc"
+        ],
+        "presentation": {
+          "echo": true,
+          "reveal": "always",
+          "focus": false,
+          "panel": "shared",
+          "clear": true
+        },
+        "group": {
+          "kind": "build",
+          "isDefault": true
+        }
+      }
+    ]
+  }
+}
\ No newline at end of file

From d77a666b1a9e1e9c36b13c5d91935b89c3733754 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 14:40:29 -0700
Subject: [PATCH 18/22] fixed lists

---
 tools/json_injector/lib/json_injector.dart | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/tools/json_injector/lib/json_injector.dart b/tools/json_injector/lib/json_injector.dart
index f37d90601a2d7..c7eec321f6938 100644
--- a/tools/json_injector/lib/json_injector.dart
+++ b/tools/json_injector/lib/json_injector.dart
@@ -4,6 +4,15 @@
 
 const String _templateKey = 'json_injector:template';
 
+bool _isListOf<T>(List<dynamic> list) {
+  for (final item in list) {
+    if (item is! T) {
+      return false;
+    }
+  }
+  return list.isNotEmpty;
+}
+
 Object? inject(Object? json, Object? injector,
     {String? nameKey, Map<String, Map<dynamic, dynamic>>? templates}) {
   Object? recurse(Object? x, Object? y) =>
@@ -33,14 +42,21 @@ Object? inject(Object? json, Object? injector,
     }
     return result;
   }
-  if (json is List<Map> && injector is List<Map> && nameKey != null) {
+  if (json is List<dynamic> &&
+      injector is List<dynamic> &&
+      nameKey != null &&
+      _isListOf<Map<dynamic, dynamic>>(json) &&
+      _isListOf<Map<dynamic, dynamic>>(injector)) {
     final Map<String, Object?> jsonList = {};
     final Map<String, Object?> injectorList = {};
+
     for (final item in json) {
-      jsonList[nameKey] = item;
+      final Map<dynamic, dynamic> map = item as Map;
+      jsonList[map[nameKey] as String] = item;
     }
     for (final item in injector) {
-      injectorList[nameKey] = item;
+      final Map<dynamic, dynamic> map = item as Map;
+      injectorList[map[nameKey] as String] = item;
     }
     final joined = recurse(jsonList, injectorList) as Map?;
     return joined?.values.toList();

From 6572c74fc6f2e09973452f50543ad412b32e75ab Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 15:02:54 -0700
Subject: [PATCH 19/22] got templates working correctly

---
 tools/json_injector/bin/main.dart             |  4 +-
 .../injectors/engine-templates.json           | 24 +++++++++++-
 .../injectors/engine.code-workspace           | 25 ++-----------
 tools/json_injector/lib/json_injector.dart    | 37 +++++++++++++++++--
 .../test/json_injector_test.dart              | 25 +++++++++++++
 5 files changed, 87 insertions(+), 28 deletions(-)

diff --git a/tools/json_injector/bin/main.dart b/tools/json_injector/bin/main.dart
index fcdd5f63bb9a1..8e151a55c1ce2 100644
--- a/tools/json_injector/bin/main.dart
+++ b/tools/json_injector/bin/main.dart
@@ -38,11 +38,11 @@ void main(List<String> arguments) {
   }
 
   final String? nameKey = argResults['name-key'] as String?;
-  Map<String, Map<dynamic, dynamic>>? templates;
+  Map<dynamic, dynamic>? templates;
   final String? templatesPath = argResults['templates'] as String?;
   if (templatesPath != null) {
     final templateJson = File(templatesPath).readAsStringSync();
-    templates = jsonDecode(templateJson) as Map<String, Map<dynamic, dynamic>>?;
+    templates = jsonDecode(templateJson) as Map<dynamic, dynamic>?;
   }
 
   late final dynamic input;
diff --git a/tools/json_injector/injectors/engine-templates.json b/tools/json_injector/injectors/engine-templates.json
index 9e26dfeeb6e64..581d3b1fed754 100644
--- a/tools/json_injector/injectors/engine-templates.json
+++ b/tools/json_injector/injectors/engine-templates.json
@@ -1 +1,23 @@
-{}
\ No newline at end of file
+{
+  "et-task": {
+    "type": "shell",
+    "command": "./flutter/bin/et",
+    "options": {
+      "cwd": "${workspaceFolder}/.."
+    },
+    "problemMatcher": [
+      "$gcc"
+    ],
+    "presentation": {
+      "echo": true,
+      "reveal": "always",
+      "focus": false,
+      "panel": "shared",
+      "clear": true
+    },
+    "group": {
+      "kind": "build",
+      "isDefault": true
+    }
+  }
+}
\ No newline at end of file
diff --git a/tools/json_injector/injectors/engine.code-workspace b/tools/json_injector/injectors/engine.code-workspace
index d29525fac3080..e900e54eba868 100644
--- a/tools/json_injector/injectors/engine.code-workspace
+++ b/tools/json_injector/injectors/engine.code-workspace
@@ -1,35 +1,16 @@
 {
   "tasks": {
-    "version": "2.0.0",
     "tasks": [
       {
         "label": "display_list_unittests_arm64",
-        "type": "shell",
-        "command": "./flutter/bin/et",
+        "json_injector:template": "et-task",
         "args": [
           "build",
           "-c",
           "host_debug_unopt_arm64",
           "//flutter/display_list:display_list_unittests"
-        ],
-        "options": {
-          "cwd": "${workspaceFolder}/.."
-        },
-        "problemMatcher": [
-          "$gcc"
-        ],
-        "presentation": {
-          "echo": true,
-          "reveal": "always",
-          "focus": false,
-          "panel": "shared",
-          "clear": true
-        },
-        "group": {
-          "kind": "build",
-          "isDefault": true
-        }
+        ]
       }
     ]
   }
-}
\ No newline at end of file
+}
diff --git a/tools/json_injector/lib/json_injector.dart b/tools/json_injector/lib/json_injector.dart
index c7eec321f6938..842a57a1e9623 100644
--- a/tools/json_injector/lib/json_injector.dart
+++ b/tools/json_injector/lib/json_injector.dart
@@ -13,8 +13,38 @@ bool _isListOf<T>(List<dynamic> list) {
   return list.isNotEmpty;
 }
 
+dynamic _applyTemplate(dynamic item, Map<dynamic, dynamic>? templates) {
+  if (item is Map) {
+    if (item.containsKey(_templateKey)) {
+      final String templateName = item[_templateKey] as String;
+      final Map<dynamic, dynamic>? template =
+          templates?[templateName] as Map<dynamic, dynamic>?;
+
+      if (template == null) {
+        throw StateError('unknown template: $templateName');
+      }
+
+      final Map<dynamic, dynamic> result = {};
+      for (final x in item.keys) {
+        if (x != _templateKey) {
+          result[x] = item[x];
+        }
+      }
+      for (final x in template.keys) {
+        result[x] = template[x];
+      }
+      return result;
+    } else {
+      return item;
+    }
+  } else if (item is List) {
+  } else {
+    return item;
+  }
+}
+
 Object? inject(Object? json, Object? injector,
-    {String? nameKey, Map<String, Map<dynamic, dynamic>>? templates}) {
+    {String? nameKey, Map<dynamic, dynamic>? templates}) {
   Object? recurse(Object? x, Object? y) =>
       inject(x, y, nameKey: nameKey, templates: templates);
   if (json is Map && injector is Map) {
@@ -27,7 +57,8 @@ Object? inject(Object? json, Object? injector,
     for (final key in injector.keys) {
       if (key == _templateKey) {
         final String templateName = injector[key] as String;
-        final Map<dynamic, dynamic>? template = templates?[templateName];
+        final Map<dynamic, dynamic>? template =
+            templates?[templateName] as Map<dynamic, dynamic>?;
         if (template == null) {
           throw StateError('unknown template: $templateName');
         }
@@ -37,7 +68,7 @@ Object? inject(Object? json, Object? injector,
       } else if (json.containsKey(key)) {
         result[key] = recurse(json[key], injector[key]);
       } else {
-        result[key] = injector[key];
+        result[key] = _applyTemplate(injector[key], templates);
       }
     }
     return result;
diff --git a/tools/json_injector/test/json_injector_test.dart b/tools/json_injector/test/json_injector_test.dart
index e260d15dcb596..2cc665ca7687c 100644
--- a/tools/json_injector/test/json_injector_test.dart
+++ b/tools/json_injector/test/json_injector_test.dart
@@ -143,4 +143,29 @@ void main() {
           ],
         }));
   });
+
+  test('new list item template', () {
+    const json = {
+      'configurations': [
+        {'name': 'foo', 'x': 1},
+      ],
+    };
+    const injector = {
+      'configurations': [
+        {'name': 'bar', 'json_injector:template': 'super'},
+      ],
+    };
+    const templates = {
+      'super': {'y': 2, 'z': 3}
+    };
+
+    expect(
+        inject(json, injector, nameKey: 'name', templates: templates),
+        _isDeepEquals({
+          'configurations': [
+            {'name': 'foo', 'x': 1},
+            {'name': 'bar', 'y': 2, 'z': 3},
+          ],
+        }));
+  });
 }

From fd26d14d6c93461affb05a4255c1c9cc2fcdec14 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 15:13:38 -0700
Subject: [PATCH 20/22] updated readme

---
 tools/json_injector/README.md                 | 25 +++++++++++++++++++
 .../injectors/engine.code-workspace           | 10 ++++++++
 2 files changed, 35 insertions(+)

diff --git a/tools/json_injector/README.md b/tools/json_injector/README.md
index e69de29bb2d1d..fe1391e3fbe45 100644
--- a/tools/json_injector/README.md
+++ b/tools/json_injector/README.md
@@ -0,0 +1,25 @@
+# json_injector
+
+## Description
+
+This is a tool to manipulate json files. It's main purpose is to reduce
+redundancy in VSCode workspaces.
+
+It can inject missing keys from one json file into another, treat List\<Map\>s as
+Maps for the purpose of merging and apply templates.
+
+## Usage
+
+The following invocation will update //engine.code-workspace, injecting the json
+data from `injectors/engine.code-workspace` and also applying the templates at
+`./injectors/engine-templates.json`.  List\<Map\>s who have the key named
+'label' will be treated as Maps whose key is "label".
+
+```shell
+dart run bin/main.dart \
+  --input ~/dev/engine/src/flutter/engine.code-workspace \
+  --injector injectors/engine.code-workspace \
+  --output ~/dev/engine/src/flutter/engine.code-workspace \
+  --name-key label \
+  --templates injectors/engine-templates.json
+```
\ No newline at end of file
diff --git a/tools/json_injector/injectors/engine.code-workspace b/tools/json_injector/injectors/engine.code-workspace
index e900e54eba868..773071d924915 100644
--- a/tools/json_injector/injectors/engine.code-workspace
+++ b/tools/json_injector/injectors/engine.code-workspace
@@ -10,6 +10,16 @@
           "host_debug_unopt_arm64",
           "//flutter/display_list:display_list_unittests"
         ]
+      },
+      {
+        "label": "impeller_unittests_arm64",
+        "json_injector:template": "et-task",
+        "args": [
+          "build",
+          "-c",
+          "host_debug_unopt_arm64",
+          "//flutter/impeller:impeller_unittests"
+        ]
       }
     ]
   }

From 40e0f7f80d1e00677fe6ab734a295124824315f2 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 15:26:56 -0700
Subject: [PATCH 21/22] adds test that uses actual output from jsonDecode

---
 tools/json_injector/lib/json_injector.dart    |  1 +
 .../test/json_injector_test.dart              | 30 +++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/tools/json_injector/lib/json_injector.dart b/tools/json_injector/lib/json_injector.dart
index 842a57a1e9623..cc8a6bf023fc2 100644
--- a/tools/json_injector/lib/json_injector.dart
+++ b/tools/json_injector/lib/json_injector.dart
@@ -38,6 +38,7 @@ dynamic _applyTemplate(dynamic item, Map<dynamic, dynamic>? templates) {
       return item;
     }
   } else if (item is List) {
+    return item;
   } else {
     return item;
   }
diff --git a/tools/json_injector/test/json_injector_test.dart b/tools/json_injector/test/json_injector_test.dart
index 2cc665ca7687c..7846c4bb2988b 100644
--- a/tools/json_injector/test/json_injector_test.dart
+++ b/tools/json_injector/test/json_injector_test.dart
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'dart:convert' show jsonDecode, jsonEncode;
+
 import 'package:json_injector/json_injector.dart';
 import 'package:test/test.dart';
 
@@ -144,6 +146,34 @@ void main() {
         }));
   });
 
+    test('simple template - json', () {
+    dynamic json = <String, Object>{
+      'configurations': [
+        {'name': 'foo', 'x': 1},
+      ],
+    };
+    dynamic injector = {
+      'configurations': [
+        {'name': 'foo', 'json_injector:template': 'super'},
+      ],
+    };
+    Map<dynamic, dynamic> templates = {
+      'super': {'y': 2, 'z': 3}
+    };
+
+    json = jsonDecode(jsonEncode(json));
+    injector = jsonDecode(jsonEncode(injector));
+    templates = jsonDecode(jsonEncode(templates)) as Map<dynamic, dynamic>;
+
+    expect(
+        inject(json, injector, nameKey: 'name', templates: templates),
+        _isDeepEquals({
+          'configurations': [
+            {'name': 'foo', 'x': 1, 'y': 2, 'z': 3},
+          ],
+        }));
+  });
+
   test('new list item template', () {
     const json = {
       'configurations': [

From 3a6109acbc38308dbab033f4f10fb139c89f5588 Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Thu, 19 Sep 2024 16:11:39 -0700
Subject: [PATCH 22/22] pub_get_offline

---
 tools/pub_get_offline.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/pub_get_offline.py b/tools/pub_get_offline.py
index 2bf6b8ace54a0..bc43990eeb5c8 100644
--- a/tools/pub_get_offline.py
+++ b/tools/pub_get_offline.py
@@ -46,7 +46,7 @@
     os.path.join(ENGINE_DIR, 'tools', 'githooks'),
     os.path.join(ENGINE_DIR, 'tools', 'golden_tests_harvester'),
     os.path.join(ENGINE_DIR, 'tools', 'header_guard_check'),
-    os.path.join(ENGINE_DIR, 'tools', 'licenses'),
+    os.path.join(ENGINE_DIR, 'tools', 'json_injector'),
     os.path.join(ENGINE_DIR, 'tools', 'path_ops', 'dart'),
     os.path.join(ENGINE_DIR, 'tools', 'pkg', 'engine_build_configs'),
     os.path.join(ENGINE_DIR, 'tools', 'pkg', 'engine_repo_tools'),