Add buildMode, icuDataPath and engineRevision interpolations for custom devices (flutter#164455)

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Make 3 additional string interpolated values available to the
`postBuild` and `runDebug` custom device commands:
- `${icuDataPath}`
- `${engineRevision}`
- `${buildMode}`

flutter#164454 provides some additional context and the main motivation for
this change.

Fixes flutter#164454.

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Author: vially

packages/flutter_tools/lib/src/custom_devices/custom_device.dart

@@ -8,6 +8,7 @@ import 'package:meta/meta.dart';
 import 'package:process/process.dart';
 
 import '../application_package.dart';
+import '../artifacts.dart';
 import '../base/common.dart';
 import '../base/file_system.dart';
 import '../base/io.dart';
@@ -21,6 +22,7 @@ import '../convert.dart';
 import '../device.dart';
 import '../device_port_forwarder.dart';
 import '../features.dart';
+import '../globals.dart' as globals;
 import '../project.dart';
 import '../protocol_discovery.dart';
 import '../vmservice.dart';
@@ -341,6 +343,7 @@ class CustomDeviceAppSession {
     Map<String, Object?> platformArgs = const <String, Object>{},
     bool prebuiltApplication = false,
     String? userIdentifier,
+    Map<String, String> additionalReplacementValues = const <String, String>{},
   }) async {
     final bool traceStartup = platformArgs['trace-startup'] as bool? ?? false;
     final String? packageName = _appPackage.name;
@@ -352,7 +355,7 @@ class CustomDeviceAppSession {
           'remotePath': '/tmp/',
           'appName': packageName,
           'engineOptions': _getEngineOptionsForCmdline(debuggingOptions, traceStartup, route),
-        });
+        }, additionalReplacementValues: additionalReplacementValues);
 
     final Process process = await _processUtils.start(interpolated);
     assert(_process == null);
@@ -700,14 +703,24 @@ class CustomDevice extends Device {
     String? userIdentifier,
     BundleBuilder? bundleBuilder,
   }) async {
+    final TargetPlatform platform = await targetPlatform;
+    final Artifacts artifacts = globals.artifacts!;
+
+    final Map<String, String> additionalReplacementValues = <String, String>{
+      'buildMode': debuggingOptions.buildInfo.modeName,
+      'icuDataPath': artifacts.getArtifactPath(Artifact.icuData, platform: platform),
+      'engineRevision':
+          artifacts.usesLocalArtifacts ? 'local' : globals.flutterVersion.engineRevision,
+    };
+
     if (!prebuiltApplication) {
       final String assetBundleDir = getAssetBuildDirectory();
 
       bundleBuilder ??= BundleBuilder();
 
       // this just builds the asset bundle, it's the same as `flutter build bundle`
       await bundleBuilder.build(
-        platform: await targetPlatform,
+        platform: platform,
         buildInfo: debuggingOptions.buildInfo,
         mainPath: mainPath,
         depfilePath: defaultDepfilePath,
@@ -720,7 +733,11 @@ class CustomDevice extends Device {
         if (packageName == null) {
           throwToolExit('Could not start app, name for $package is unknown.');
         }
-        await _tryPostBuild(appName: packageName, localPath: assetBundleDir);
+        await _tryPostBuild(
+          appName: packageName,
+          localPath: assetBundleDir,
+          additionalReplacementValues: additionalReplacementValues,
+        );
       }
     }
 
@@ -736,6 +753,7 @@ class CustomDevice extends Device {
       platformArgs: platformArgs,
       prebuiltApplication: prebuiltApplication,
       userIdentifier: userIdentifier,
+      additionalReplacementValues: additionalReplacementValues,
     );
   }
 

packages/flutter_tools/static/custom-devices.schema.json

@@ -59,7 +59,7 @@
             "required": false
           },
           "postBuild": {
-            "description": "The command to be invoked after the build process is done, to do any additional packaging for example.",
+            "description": "The command to be invoked after the build process is done, to do any additional packaging for example. The following variables are available via string interpolation:\n- ${appName}\n- ${localPath}\n- ${buildMode}\n- ${icuDataPath}\n- ${engineRevision}",
             "type": ["array", "null"],
             "items": {
               "type": "string"
@@ -91,7 +91,7 @@
             ]
           },
           "runDebug": {
-            "description": "The command to be invoked to run the app in debug mode. The name of the app to be started is available via the ${appName} string interpolation. Make sure the flutter cmdline output is available via this commands stdout/stderr since the SDK needs the \"VM Service is now listening on ...\" message to function. If the forwardPort command is not specified, the VM Service URL will be connected to as-is, without any port forwarding. In that case you need to make sure it is reachable from your host device, possibly via the \"--vm-service-host=<ip>\" engine flag.",
+            "description": "The command to be invoked to run the app in debug mode. Make sure the flutter cmdline output is available via this commands stdout/stderr since the SDK needs the \"VM Service is now listening on ...\" message to function. If the forwardPort command is not specified, the VM Service URL will be connected to as-is, without any port forwarding. In that case you need to make sure it is reachable from your host device, possibly via the \"--vm-service-host=<ip>\" engine flag. The following variables are available via string interpolation:\n- ${appName}\n- ${engineOptions}\n- ${buildMode}\n- ${icuDataPath}\n- ${engineRevision}",
             "type": "array",
             "items": {
               "type": "string"

packages/flutter_tools/test/general.shard/custom_devices/custom_device_test.dart

@@ -7,6 +7,7 @@ import 'dart:async';
 import 'package:file/file.dart';
 import 'package:file/memory.dart';
 import 'package:file_testing/file_testing.dart';
+import 'package:flutter_tools/src/artifacts.dart';
 import 'package:flutter_tools/src/base/logger.dart';
 import 'package:flutter_tools/src/build_info.dart';
 import 'package:flutter_tools/src/build_system/build_system.dart';
@@ -530,6 +531,100 @@ void main() {
     },
   );
 
+  testUsingContext(
+    'custom device command string interpolation end-to-end test',
+    () async {
+      final Completer<void> runDebugCompleter = Completer<void>();
+
+      final CustomDeviceConfig config = testConfig.copyWith(
+        platform: TargetPlatform.linux_arm64,
+        postBuildCommand: const <String>[
+          'testpostbuild',
+          r'--buildMode=${buildMode}',
+          r'--icuDataPath=${icuDataPath}',
+          r'--engineRevision=${engineRevision}',
+        ],
+        runDebugCommand: const <String>[
+          'testrundebug',
+          r'--buildMode=${buildMode}',
+          r'--icuDataPath=${icuDataPath}',
+          r'--engineRevision=${engineRevision}',
+        ],
+      );
+
+      final List<Pattern> commandArgumentsPattern = <Pattern>[
+        RegExp(r'--buildMode=.*'),
+        RegExp(r'--icuDataPath=.*'),
+        RegExp(r'--engineRevision=.*'),
+      ];
+
+      final String expectedIcuDataPath = globals.artifacts!.getArtifactPath(
+        Artifact.icuData,
+        platform: config.platform,
+      );
+      final String expectedEngineRevision = globals.flutterVersion.engineRevision;
+
+      final List<String> expectedCommandArguments = <String>[
+        '--buildMode=debug',
+        '--icuDataPath=$expectedIcuDataPath',
+        '--engineRevision=$expectedEngineRevision',
+      ];
+
+      final List<String> expectedRunDebugCommand = <String>[
+        'testrundebug',
+        ...expectedCommandArguments,
+      ];
+      final List<String> expectedPostBuildCommand = <String>[
+        'testpostbuild',
+        ...expectedCommandArguments,
+      ];
+
+      final FakeProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+        FakeCommand(
+          command: <Pattern>['testpostbuild', ...commandArgumentsPattern],
+          onRun: (List<String> command) => expect(command, expectedPostBuildCommand),
+        ),
+        FakeCommand(command: config.uninstallCommand),
+        FakeCommand(command: config.installCommand),
+        FakeCommand(
+          command: <Pattern>['testrundebug', ...commandArgumentsPattern],
+          completer: runDebugCompleter,
+          onRun: (List<String> command) => expect(command, expectedRunDebugCommand),
+          stdout: 'The Dart VM service is listening on http://127.0.0.1:12345/abcd/\n',
+        ),
+        FakeCommand(
+          command: config.forwardPortCommand!,
+          stdout: testConfigForwardPortSuccessOutput,
+        ),
+      ]);
+
+      // CustomDevice.startApp doesn't care whether we pass a prebuilt app or
+      // buildable app as long as we pass prebuiltApplication as false
+      final PrebuiltLinuxApp app = PrebuiltLinuxApp(executable: 'testexecutable');
+
+      // finally start actually testing things
+      final CustomDevice device = CustomDevice(
+        config: config,
+        logger: BufferLogger.test(),
+        processManager: processManager,
+      );
+
+      await device.startApp(
+        app,
+        debuggingOptions: DebuggingOptions.enabled(BuildInfo.debug),
+        bundleBuilder: FakeBundleBuilder(),
+      );
+      expect(runDebugCompleter.isCompleted, false);
+
+      expect(await device.stopApp(app), true);
+      expect(runDebugCompleter.isCompleted, true);
+    },
+    overrides: <Type, Generator>{
+      FileSystem: () => MemoryFileSystem.test(),
+      ProcessManager: () => FakeProcessManager.any(),
+    },
+  );
+
   testWithoutContext('CustomDevice screenshotting', () async {
     bool screenshotCommandWasExecuted = false;