feat(scala): add scala schema idl support

.github/workflows/ci.yml

@@ -597,6 +597,41 @@ jobs:
         run: |
           cd scala && sbt +test && cd -
 
+  scala_xlang:
+    name: Scala Xlang Test
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+      - name: Set up JDK 21
+        uses: actions/setup-java@v4
+        with:
+          java-version: 21
+          distribution: "temurin"
+          cache: sbt
+      - name: Set up Python 3.11
+        uses: actions/setup-python@v5
+        with:
+          python-version: 3.11
+      - name: Cache Maven local repository
+        uses: actions/cache@v4
+        with:
+          path: ~/.m2/repository
+          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
+          restore-keys: |
+            ${{ runner.os }}-maven-
+      - uses: sbt/setup-sbt@1cad58d595b729a71ca2254cdf5b43dd6f42d4bb # v1.1.18
+      - name: Run Scala Xlang Test
+        env:
+          FORY_SCALA_JAVA_CI: "1"
+          ENABLE_FORY_DEBUG_OUTPUT: "1"
+        run: |
+          cd java
+          mvn -T16 --no-transfer-progress clean install -DskipTests -Dmaven.javadoc.skip=true -Dmaven.source.skip=true
+          cd fory-core
+          mvn -T16 --no-transfer-progress test -Dtest=org.apache.fory.xlang.ScalaXlangTest
+      - name: Run Scala IDL Tests
+        run: ./integration_tests/idl_tests/run_scala_tests.sh
+
   integration_tests:
     name: Integration Tests
     runs-on: ubuntu-latest

AGENTS.md

@@ -67,6 +67,7 @@ This is the entry point for AI guidance in Apache Fory. Read this file first, th
 - Only add tests that verify internal behaviors or fix specific bugs; do not create unnecessary tests unless requested.
 - Do not add cleanup-sentinel tests that only pin deleted APIs or removed fields.
 - Tests must exercise the actual code you wrote or changed. Do not write tests that pass by exercising a pre-existing code path that produces similar-looking results. Before writing a test, identify the exact new code path (annotation, codegen output, new API) and verify the test would fail if that code path were removed. When the change involves codegen or annotations, the test must use those annotations on real structs, run through the codegen pipeline, and verify the generated output drives the expected runtime behavior.
+- Keep test method names concise. Name the behavior under test without encoding the whole scenario or expected result in the method name.
 - When reading code, skip files not tracked by git by default unless you generated them yourself or the task explicitly requires them.
 - Maintain cross-language consistency while respecting language-specific idioms.
 - Keep one active ownership path per concept. Do not leave duplicate serializers, resolvers, helpers, or registration paths for the same type family unless the split is deliberate and documented.

compiler/README.md

@@ -4,7 +4,7 @@ The FDL compiler generates cross-language serialization code from schema definit
 
 ## Features
 
-- **Multi-language code generation**: Java, Python, Go, Rust, C++, C#, JavaScript, and Swift
+- **Multi-language code generation**: Java, Python, Go, Rust, C++, C#, JavaScript, Swift, Dart, and Scala
 - **Rich type system**: Primitives, enums, messages, lists, dense arrays, maps
 - **Cross-language serialization**: Generated code works seamlessly with Apache Fory
 - **Type ID and namespace support**: Both numeric IDs and name-based type registration
@@ -64,16 +64,16 @@ message Cat [id=103] {
 foryc schema.fdl --output ./generated
 
 # Generate for specific languages
-foryc schema.fdl --lang java,python,csharp,javascript --output ./generated
+foryc schema.fdl --lang java,python,csharp,javascript,scala --output ./generated
 
 # Override package name
 foryc schema.fdl --package myapp.models --output ./generated
 
 # Language-specific output directories (protoc-style)
-foryc schema.fdl --java_out=./src/main/java --python_out=./python/src --csharp_out=./csharp/src/Generated --javascript_out=./javascript
+foryc schema.fdl --java_out=./src/main/java --python_out=./python/src --csharp_out=./csharp/src/Generated --javascript_out=./javascript --scala_out=./scala/src/main/scala
 
 # Combine with other options
-foryc schema.fdl --java_out=./gen --go_out=./gen/go --csharp_out=./gen/csharp --javascript_out=./gen/js -I ./proto
+foryc schema.fdl --java_out=./gen --go_out=./gen/go --csharp_out=./gen/csharp --javascript_out=./gen/js --scala_out=./gen/scala -I ./proto
 ```
 
 ### 3. Use Generated Code
@@ -318,12 +318,12 @@ Each generator extends `BaseGenerator` and implements:
 Generates POJOs with:
 
 - Private fields with getters/setters
-- `@Nullable` annotations for nullable fields and `@ForyField` annotations for ref fields
+- `@Nullable` annotations for nullable fields and `@Ref` annotations for ref fields
 - Registration helper class
 
 ```java
 public class Cat {
-    @ForyField(ref = true)
+    @Ref
     private Dog friend;
 
     @Nullable
@@ -457,7 +457,7 @@ Arguments:
   FILES                 FDL files to compile
 
 Options:
-  --lang TEXT          Target languages (java,python,cpp,rust,go,csharp,javascript or "all")
+  --lang TEXT          Target languages (java,python,cpp,rust,go,csharp,javascript,swift,dart,scala or "all")
                        Default: all
   --output, -o PATH    Output directory
                        Default: ./generated

compiler/fory_compiler/cli.py

@@ -264,7 +264,7 @@ def parse_args(args: Optional[List[str]] = None) -> argparse.Namespace:
         "--lang",
         type=str,
         default="all",
-        help="Comma-separated list of target languages (java,python,cpp,rust,go,csharp,javascript,swift,dart). Default: all",
+        help="Comma-separated list of target languages (java,python,cpp,rust,go,csharp,javascript,swift,dart,scala). Default: all",
     )
 
     parser.add_argument(
@@ -367,6 +367,14 @@ def parse_args(args: Optional[List[str]] = None) -> argparse.Namespace:
         help="Generate Dart code in DST_DIR",
     )
 
+    parser.add_argument(
+        "--scala_out",
+        type=Path,
+        default=None,
+        metavar="DST_DIR",
+        help="Generate Scala 3 code in DST_DIR",
+    )
+
     parser.add_argument(
         "--go_nested_type_style",
         type=str,
@@ -672,6 +680,7 @@ def cmd_compile(args: argparse.Namespace) -> int:
         "javascript": args.javascript_out,
         "swift": args.swift_out,
         "dart": args.dart_out,
+        "scala": args.scala_out,
     }
 
     # Determine which languages to generate

compiler/fory_compiler/generators/__init__.py

@@ -27,6 +27,7 @@
 from fory_compiler.generators.javascript import JavaScriptGenerator
 from fory_compiler.generators.swift import SwiftGenerator
 from fory_compiler.generators.dart import DartGenerator
+from fory_compiler.generators.scala import ScalaGenerator
 
 GENERATORS = {
     "java": JavaGenerator,
@@ -38,6 +39,7 @@
     "javascript": JavaScriptGenerator,
     "swift": SwiftGenerator,
     "dart": DartGenerator,
+    "scala": ScalaGenerator,
 }
 
 __all__ = [
@@ -51,5 +53,6 @@
     "JavaScriptGenerator",
     "SwiftGenerator",
     "DartGenerator",
+    "ScalaGenerator",
     "GENERATORS",
 ]