Flutter: port ordinary apps unmodified (language, dart:io/convert, pub packages, plugin stubs)

.github/workflows/flutter-acceptance.yml

@@ -0,0 +1,82 @@
+name: Flutter app acceptance
+
+# Imports, transpiles and compiles the "ordinary" Flutter apps under
+# scripts/flutter-apps with no edits (scripts/flutter-apps/run-acceptance.sh).
+# The unit and behavior tests (dart-flutter-tests.yml) check constructs one at a
+# time; this checks that a whole app built from pub packages and plugins gets
+# through the importer, the transpiler and javac together.
+#
+# `flutter pub get` is real: the importer transpiles pure-Dart dependencies
+# (dio, ...) from the pub cache, so the Flutter SDK is needed for resolution,
+# never to build anything.
+
+on:
+  pull_request:
+    paths:
+      - 'maven/dart-transpiler/**'
+      - 'maven/dart-runtime/**'
+      - 'maven/flutter-runtime/**'
+      - 'maven/build-engine/src/main/java/com/codename1/maven/FlutterProjectImporter.java'
+      - 'scripts/flutter-apps/**'
+      - '.github/workflows/flutter-acceptance.yml'
+  push:
+    branches:
+      - master
+    paths:
+      - 'maven/dart-transpiler/**'
+      - 'maven/dart-runtime/**'
+      - 'maven/flutter-runtime/**'
+      - 'maven/build-engine/src/main/java/com/codename1/maven/FlutterProjectImporter.java'
+      - 'scripts/flutter-apps/**'
+      - '.github/workflows/flutter-acceptance.yml'
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event_name }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  acceptance:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 45
+    env:
+      LANG: C.UTF-8
+      LC_ALL: C.UTF-8
+    steps:
+      - uses: actions/checkout@v6
+
+      - uses: actions/setup-java@v5
+        with:
+          distribution: temurin
+          java-version: '17'
+
+      - name: Cache Maven dependencies
+        uses: actions/cache@v5
+        with:
+          path: ~/.m2
+          key: ${{ runner.os }}-m2-flutter-acceptance-${{ hashFiles('**/pom.xml') }}
+          restore-keys: |
+            ${{ runner.os }}-m2-flutter-acceptance-
+            ${{ runner.os }}-m2
+
+      - uses: subosito/flutter-action@v2
+        with:
+          channel: stable
+          flutter-version: '3.35.4'
+
+      # The runtimes join the reactor only on JDK 17+ (flutter-modules).
+      - name: Build the transpiler and runtimes
+        env:
+          RETRY_ONLY_MATCHING: transient
+        run: |
+          cd maven
+          bash ../scripts/ci/retry.sh mvn -B install \
+            -pl core,dart-runtime,flutter-runtime,dart-transpiler -am -DskipTests \
+            -Dmaven.javadoc.skip=true -Dmaven.source.skip=true \
+            -Dspotbugs.skip=true -Dpmd.skip=true -Dcheckstyle.skip=true -Djacoco.skip=true
+
+      - name: Import, transpile and compile each app
+        run: JAVA17_HOME="$JAVA_HOME" scripts/flutter-apps/run-acceptance.sh

maven/build-engine/src/test/java/com/codename1/maven/FlutterProjectImporterTest.java

@@ -88,7 +88,8 @@ public void importsLibTreeAssetsAndFontsAndReportsDependencies() throws Exceptio
         File root = Files.createTempDirectory("flutter-import").toFile();
         File flutterProject = new File(root, "demo");
         write(new File(flutterProject, "pubspec.yaml"), PUBSPEC);
-        write(new File(flutterProject, "lib/main.dart"), "void main() {}\n");
+        // imported, so it is a real dependency: one lib/ never imports is not reported
+        write(new File(flutterProject, "lib/main.dart"), "import 'package:some_uncovered_pkg/a.dart';\nvoid main() {}\n");
         write(new File(flutterProject, "lib/pages/home.dart"), "class Home {}\n");
         write(new File(flutterProject, "assets/images/logo.png"), "PNGDATA");
         write(new File(flutterProject, "assets/icons/a.png"), "ICONA");
@@ -103,7 +104,8 @@ public void importsLibTreeAssetsAndFontsAndReportsDependencies() throws Exceptio
         assertEquals("1.2.3+4", r.appVersion);
         assertTrue(r.covered.toString(), r.covered.get(0).startsWith("flutter ("));
         assertTrue(r.covered.toString(), r.covered.get(1).startsWith("cupertino_icons ("));
-        assertEquals(java.util.Collections.singletonList("some_uncovered_pkg"), r.uncovered);
+        assertEquals(r.uncovered.toString(), 1, r.uncovered.size());
+        assertTrue(r.uncovered.toString(), r.uncovered.get(0).startsWith("some_uncovered_pkg (sources not found"));
         assertTrue(r.missingAssets.toString(), r.missingAssets.isEmpty());
 
         File flutterDir = new File(common, "src/main/flutter");
@@ -368,6 +370,37 @@ public void anAssetNeverOverwritesALibSourceAtTheSamePath() throws Exception {
 
     /// lib/ is copied flat, so lib/assets/x.dart shares assets/ with the bundled
     /// assets; the lib-sources record lists exactly the Dart files that came from lib/.
+    /// A pure-Dart package importing an unsupported one cannot compile either: the
+    /// verdict travels to it, and none of its files reach the build.
+    @Test
+    public void aPackageImportingAnUnsupportedOneIsUnsupportedToo() throws Exception {
+        File root = Files.createTempDirectory("flutter-transitive").toFile();
+        File flutterProject = new File(root, "demo");
+        write(new File(flutterProject, "pubspec.yaml"), "name: demo\nversion: 1.0.0\n"
+                + "dependencies:\n  flutter:\n    sdk: flutter\n  outer: 1.0.0\n");
+        write(new File(flutterProject, "lib/main.dart"), "import 'package:outer/outer.dart';\nvoid main() {}\n");
+        File outer = new File(root, "cache/outer-1.0.0");
+        write(new File(outer, "lib/outer.dart"), "import 'package:inner/inner.dart';\nint o() => 1;\n");
+        File inner = new File(root, "cache/inner-1.0.0");
+        write(new File(inner, "lib/inner.dart"), "import 'dart:mirrors';\nint i() => 1;\n");
+        write(new File(flutterProject, ".dart_tool/package_config.json"), "{\n  \"configVersion\": 2,\n"
+                + "  \"packages\": [\n"
+                + "    {\n      \"name\": \"outer\",\n      \"rootUri\": \"" + outer.toURI()
+                + "\",\n      \"packageUri\": \"lib/\"\n    },\n"
+                + "    {\n      \"name\": \"inner\",\n      \"rootUri\": \"" + inner.toURI()
+                + "\",\n      \"packageUri\": \"lib/\"\n    }\n"
+                + "  ]\n}\n");
+
+        File common = new File(root, "common");
+        FlutterProjectImporter.Result r = new FlutterProjectImporter(new com.codename1.build.SystemStreamLog())
+                .importProject(flutterProject, common, null, null);
+
+        assertTrue(r.unsupportedPackages.toString(), r.unsupportedPackages.containsKey("inner"));
+        assertTrue(r.unsupportedPackages.toString(),
+                String.valueOf(r.unsupportedPackages.get("outer")).startsWith("depends on inner"));
+        assertFalse(new File(common, "src/main/flutter/packages/outer/outer.dart").exists());
+    }
+
     @Test
     public void recordsTheDartSourcesCopiedFromLib() throws Exception {
         File root = Files.createTempDirectory("flutter-lib-sources").toFile();
@@ -661,4 +694,45 @@ private static void write(File f, String content) throws IOException {
     private static String read(File f) throws IOException {
         return new String(Files.readAllBytes(f.toPath()), "UTF-8");
     }
+
+    @Test
+    public void entryPointForwardsPluginCallbacksOnlyWhenUsed() {
+        String plain = FlutterProjectImporter.entryPointSource("com.example", "Main", "com.example.flutter",
+                java.util.Arrays.asList("flutter", "dio"));
+        assertFalse(plain.contains("implements"));
+        assertFalse(plain.contains("AppLinks"));
+        assertTrue(plain.contains("com.example.flutter.FlutterRegistry.invokeMain();"));
+        // naming com.codename1.push makes the Android build require google-services.json
+        assertFalse(plain.contains("com.codename1.push"));
+
+        String all = FlutterProjectImporter.entryPointSource("com.example", "Main", "com.example.flutter",
+                java.util.Arrays.asList("app_links", "flutter_local_notifications", "firebase_messaging"));
+        assertTrue(all.contains("implements com.codename1.notifications.LocalNotificationCallback, "
+                + "com.codename1.push.PushCallback"));
+        assertTrue(all.contains("AppLinks.appStarted();\n        super.start();"));
+        assertTrue(all.contains("FlutterLocalNotificationsPlugin.notificationTapped(notificationId);"));
+        assertTrue(all.contains("FirebaseMessaging.pushReceived(value);"));
+        assertTrue(all.contains("return com.codename1.push.Push.getPushKey();"));
+        assertTrue(all.contains("com.codename1.push.Push.subscribeToTopic(topic);"));
+    }
+
+    @Test
+    public void pluginPacksAreCovered() {
+        for (String p : new String[] {"share_plus", "geolocator", "image_picker", "firebase_auth",
+                "firebase_messaging", "google_maps_flutter", "flutter_local_notifications", "app_links"}) {
+            assertTrue(p, FlutterProjectImporter.COVERED.containsKey(p));
+        }
+    }
+
+    @Test
+    public void importLookingTextInTripleQuotedStringsIsNotADirective() {
+        String src = "import 'package:real/real.dart';\n"
+                + "const doc = \"\"\"\nimport 'package:fake/fake.dart';\n\"\"\";\n"
+                + "const raw = r'''\nimport 'package:fake2/x.dart';\\\n''';\n"
+                + "const re = r'\\d';\nimport 'package:after/after.dart';\n";
+        String out = FlutterProjectImporter.stripComments(src);
+        assertTrue(out, out.contains("package:real/real.dart"));
+        assertTrue(out, out.contains("package:after/after.dart"));
+        assertFalse(out, out.contains("fake"));
+    }
 }

maven/codenameone-maven-plugin/src/main/java/com/codename1/maven/TranscodeFlutterMojo.java

@@ -97,6 +97,7 @@ public class TranscodeFlutterMojo extends AbstractCN1Mojo {
     protected void executeImpl() throws MojoExecutionException, MojoFailureException {
         if (flutterSourceDir == null || !flutterSourceDir.isDirectory()) {
             sweepStaleOutput();
+            removeDeselectedPackClasses();
             // Flutter was removed from the project: its assets go with it.
             removeStaleAssets(new HashSet<String>());
             return;
@@ -116,6 +117,15 @@ protected void executeImpl() throws MojoExecutionException, MojoFailureException
                 req.stubClasspathEntry(a.getFile());
             }
         }
+        // The app's own Java can name a plugin pack too (the import-generated entry point
+        // installs the firebase_messaging and app_links hooks): the transpiler copies
+        // exactly the packs that are named, so it must see that Java as well.
+        for (Object root : project.getCompileSourceRoots()) {
+            File dir = new File(String.valueOf(root));
+            if (dir.isDirectory() && !dir.getAbsoluteFile().equals(flutterOutputDir.getAbsoluteFile())) {
+                req.javaSourceRoot(dir);
+            }
+        }
         TranspileResult result = new DartTranspiler().transpile(req);
         for (Diagnostic d : result.getDiagnostics()) {
             String msg = "src/main/flutter/" + d.file + ":[" + d.line + "," + d.col + "] "
@@ -139,10 +149,32 @@ protected void executeImpl() throws MojoExecutionException, MojoFailureException
         } else {
             getLog().info("Transpiled Flutter sources to " + flutterOutputDir);
         }
+        removeDeselectedPackClasses();
         copyAssets();
         registerSourceRoot();
     }
 
+    /**
+     * The transpiler deletes the source of a plugin pack the app stopped naming, but javac
+     * does not reliably delete the class compiled from it on an earlier build. Left in
+     * target/classes, those classes would still ship -- and still imply the permissions
+     * (location, push, ...) the builders derive from the classes they find.
+     */
+    private void removeDeselectedPackClasses() {
+        String packs = "com/codename1/flutter/plugins".replace('/', File.separatorChar);
+        File[] compiled = new File(project.getBuild().getOutputDirectory(), packs).listFiles();
+        if (compiled == null) {
+            return;
+        }
+        File selected = new File(flutterOutputDir, packs);
+        for (File pack : compiled) {
+            if (pack.isDirectory() && !new File(selected, pack.getName()).isDirectory()) {
+                deleteRecursive(pack);
+                getLog().debug("Removed classes of unused Flutter plugin pack " + pack.getName());
+            }
+        }
+    }
+
     private void checkJdk() throws MojoFailureException {
         String spec = System.getProperty("java.specification.version", "1.8");
         int major;