add lifecycle component traits and tests

Author: halotukozak

core/jvm/src/test/scala/com/avsystem/commons/di/LifeCycleComponentTest.scala

@@ -0,0 +1,81 @@
+package com.avsystem.commons
+package di
+
+import monix.execution.atomic.{Atomic, AtomicBoolean, AtomicInt}
+import org.scalatest.funsuite.AsyncFunSuite
+
+class LifeCycleComponentTest extends AsyncFunSuite with Components {
+
+  object init {
+    val inits: AtomicInt = Atomic(0)
+    val component: Component[InitializingComponent] = singleton {
+      new InitializingComponent {
+        override def init(): Unit = inits += 1
+      }
+    }
+  }
+
+  object asyncInit {
+    val inits: AtomicInt = Atomic(0)
+    val component: Component[AsyncInitializingComponent] = singleton {
+      new AsyncInitializingComponent {
+        def init()(implicit ec: ExecutionContext): Future[Unit] = Future {
+          inits += 1
+        }(ec)
+      }
+    }
+  }
+
+  object disposable {
+    val destroyed: AtomicBoolean = Atomic(false)
+    val component: Component[DisposableComponent] = singleton {
+      new DisposableComponent {
+        def destroy(): Unit = destroyed.set(true)
+      }
+    }
+  }
+
+
+  object asyncDisposable {
+    val destroyed: AtomicBoolean = Atomic(false)
+    val component: Component[AsyncDisposableComponent] = singleton {
+      new AsyncDisposableComponent {
+        def destroy()(implicit ec: ExecutionContext): Future[Unit] = Future {
+          destroyed.set(true)
+        }(ec)
+      }
+    }
+  }
+
+  test("InitializingComponent singleton initializes once and returns same instance")(for {
+    _ <- Future.unit
+    _ = assert(init.inits.get() == 0)
+    c1 <- init.component.init
+    _ = assert(init.inits.get() == 1)
+    c2 <- init.component.init
+    _ = assert(init.inits.get() == 1)
+  } yield assert(c1 eq c2))
+
+  test("AsyncInitializingComponent singleton initializes once and returns same instance")(for {
+    _ <- Future.unit
+    _ = assert(asyncInit.inits.get() == 0)
+    c1 <- asyncInit.component.init
+    _ = assert(asyncInit.inits.get() == 1)
+    c2 <- asyncInit.component.init
+    _ = assert(asyncInit.inits.get() == 1)
+  } yield assert(c1 eq c2))
+
+  test("DisposableComponent destroy triggers side effect") {
+    assert(!disposable.destroyed.get())
+    disposable.component.destroy.map { _ =>
+      assert(disposable.destroyed.get())
+    }
+  }
+
+  test("AsyncDisposableComponent destroy triggers side effect") {
+    assert(!asyncDisposable.destroyed.get())
+    asyncDisposable.component.destroy.map { _ =>
+      assert(asyncDisposable.destroyed.get())
+    }
+  }
+}

core/src/main/scala/com/avsystem/commons/di/LifeCycleComponents.scala

@@ -0,0 +1,20 @@
+package com.avsystem.commons
+package di
+
+trait InitializingComponent {
+  def init(): Unit
+  final def initialized(): this.type = init().thenReturn(this)
+}
+
+trait DisposableComponent {
+  def destroy(): Unit
+}
+
+trait AsyncInitializingComponent {
+  def init()(implicit ec: ExecutionContext): Future[Unit]
+  final def initialized()(implicit ec: ExecutionContext): Future[this.type] = init()(using ec).map[this.type](_ => this)(using ec)
+}
+
+trait AsyncDisposableComponent {
+  def destroy()(implicit ec: ExecutionContext): Future[Unit]
+}