Add support for --dart-flags in FlutterShellArgs. (flutter#44855) (fl…

…utter#13855)

shell/platform/android/BUILD.gn

@@ -422,6 +422,7 @@ action("robolectric_tests") {
     "test/io/flutter/embedding/engine/FlutterEngineCacheTest.java",
     "test/io/flutter/embedding/engine/FlutterEngineTest.java",
     "test/io/flutter/embedding/engine/FlutterJNITest.java",
+    "test/io/flutter/embedding/engine/FlutterShellArgsTest.java",
     "test/io/flutter/embedding/engine/PluginComponentTest.java",
     "test/io/flutter/embedding/engine/RenderingComponentTest.java",
     "test/io/flutter/embedding/engine/dart/DartExecutorTest.java",

shell/platform/android/io/flutter/embedding/engine/FlutterShellArgs.java

@@ -44,6 +44,8 @@ public class FlutterShellArgs {
   public static final String ARG_VERBOSE_LOGGING = "--verbose-logging";
   public static final String ARG_KEY_OBSERVATORY_PORT = "observatory-port";
   public static final String ARG_OBSERVATORY_PORT = "--observatory-port=";
+  public static final String ARG_KEY_DART_FLAGS = "dart-flags";
+  public static final String ARG_DART_FLAGS = "--dart-flags";
 
   @NonNull
   public static FlutterShellArgs fromIntent(@NonNull Intent intent) {
@@ -91,6 +93,14 @@ public static FlutterShellArgs fromIntent(@NonNull Intent intent) {
       args.add(ARG_VERBOSE_LOGGING);
     }
 
+    // NOTE: all flags provided with this argument are subject to filtering
+    // based on a whitelist in shell/common/switches.cc. If any flag provided
+    // is not present in the whitelist, the process will immediately
+    // terminate.
+    if (intent.hasExtra(ARG_KEY_DART_FLAGS)) {
+      args.add(ARG_DART_FLAGS + "=" + intent.getStringExtra(ARG_KEY_DART_FLAGS));
+    }
+
     return new FlutterShellArgs(args);
   }
 

shell/platform/android/test/io/flutter/FlutterTestSuite.java

@@ -23,6 +23,7 @@
 import io.flutter.plugin.platform.SingleViewPresentationTest;
 import io.flutter.util.PreconditionsTest;
 import test.io.flutter.embedding.engine.FlutterEngineTest;
+import test.io.flutter.embedding.engine.FlutterShellArgsTest;
 import test.io.flutter.embedding.engine.PluginComponentTest;
 import test.io.flutter.embedding.engine.dart.DartExecutorTest;
 
@@ -36,6 +37,7 @@
     FlutterEngineTest.class,
     FlutterFragmentTest.class,
     FlutterJNITest.class,
+    FlutterShellArgsTest.class,
     FlutterRendererTest.class,
     FlutterViewTest.class,
     PlatformChannelTest.class,

shell/platform/android/test/io/flutter/embedding/engine/FlutterShellArgsTest.java

@@ -0,0 +1,30 @@
+package test.io.flutter.embedding.engine;
+
+import android.content.Intent;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.annotation.Config;
+
+import io.flutter.embedding.engine.FlutterShellArgs;
+
+import static org.junit.Assert.assertEquals;
+
+@Config(manifest=Config.NONE)
+@RunWith(RobolectricTestRunner.class)
+public class FlutterShellArgsTest {
+  @Test
+  public void itProcessesDartFlags() {
+    // Setup the test.
+    Intent intent = new Intent();
+    intent.putExtra("dart-flags", "--observe --no-hot --no-pub");
+
+    // Execute the behavior under test.
+    FlutterShellArgs args = FlutterShellArgs.fromIntent(intent);
+
+    // Verify results.
+    assertEquals(1, args.toArray().length);
+    assertEquals("--dart-flags=--observe --no-hot --no-pub", args.toArray()[0]);
+  }
+}