Add a test target to SwiftPM package. (#9557)

Author: shoumikhin

Package.swift

@@ -82,5 +82,24 @@ let package = Package(
           (value["libraries"] as? [String] ?? []).map { .linkedLibrary($0) }
       ),
     ]
-  }
+  } + [
+    .testTarget(
+      name: "tests",
+      dependencies: [
+        .target(name: "executorch_debug"),
+        .target(name: "kernels_portable"),
+      ],
+      path: "extension/apple/ExecuTorch/__tests__",
+      resources: [
+        .copy("resources/add.pte")
+      ],
+      linkerSettings: [
+        .linkedLibrary("c++"),
+        .unsafeFlags([
+          "-Xlinker", "-force_load",
+          "-Xlinker", "cmake-out/kernels_portable.xcframework/macos-arm64/libkernels_portable_macos.a",
+        ])
+      ]
+    )
+  ]
 )

extension/apple/ExecuTorch/__tests__/ModuleTest.swift

@@ -11,9 +11,16 @@
 import XCTest
 
 class ModuleTest: XCTestCase {
+  var resourceBundle: Bundle {
+#if SWIFT_PACKAGE
+    return Bundle.module
+#else
+    return Bundle(for: type(of: self))
+#endif
+  }
+  
   func test() throws {
-    let bundle = Bundle(for: type(of: self))
-    guard let modelPath = bundle.path(forResource: "add", ofType: "pte") else {
+    guard let modelPath = resourceBundle.path(forResource: "add", ofType: "pte") else {
       XCTFail("Couldn't find the model file")
       return
     }

scripts/build_apple_frameworks.sh

@@ -206,7 +206,7 @@ cmake_build() {
     cmake --build . \
         --config "$mode" \
         --verbose
-    cd ..
+    cd -
 }
 
 for index in ${!PLATFORMS[*]}; do
@@ -285,4 +285,9 @@ done
 
 rm -rf "$HEADERS_PATH"
 
+echo "Running tests"
+
+cd "$SOURCE_ROOT_DIR"
+swift test
+
 echo "Build succeeded!"