Update TODO with finished tasks for 0.1.3.

TODO.md

@@ -34,8 +34,8 @@ For example:
 - [x] wvcc bug: Nested static view classes are not seen by compiler
   - This required tweaking how the configurations are passed around. Ultimately, we should strive for less complexity
     in this regard.
-- [ ] `OutletContainer` trait or interface for components which can contain an `<Outlet />` child.
-- [ ] `Context` should have methods for simply finding an ancestor of a certain type without the need for a predicate.
+- [x] `OutletContainer` trait or interface for components which can contain an `<Outlet />` child.
+- [x] `Context` should have methods for simply finding an ancestor of a certain type without the need for a predicate.
 
 ## 0.1.2
 - [x] `Outlet` component for rendering children like so:

view-components/src/main/java/groowt/view/component/context/ComponentContext.java

@@ -99,6 +99,23 @@ public interface ComponentContext {
         return ancestorClass.cast(this.findNearestAncestor(matching.and(ancestorClass::isInstance)));
     }
 
+    default <T extends ViewComponent> @Nullable T findNearestAncestor(Class<T> ancestorClass) {
+        return ancestorClass.cast(this.findNearestAncestor(ancestorClass::isInstance));
+    }
+
+    boolean hasAncestor(Predicate<? super ViewComponent> matching);
+
+    default <T extends ViewComponent> boolean hasAncestor(
+            Class<T> ancestorClass,
+            Predicate<? super ViewComponent> matching
+    ) {
+        return this.hasAncestor(matching.and(ancestorClass::isInstance));
+    }
+
+    default <T extends ViewComponent> boolean hasAncestor(Class<T> ancestorClass) {
+        return this.hasAncestor(ancestorClass::isInstance);
+    }
+
     List<ViewComponent> getAllAncestors();
 
 }

view-components/src/main/java/groowt/view/component/context/DefaultComponentContext.java

@@ -70,7 +70,10 @@ public class DefaultComponentContext implements ComponentContext {
     public @Nullable ViewComponent findNearestAncestor(Predicate<? super ViewComponent> matching) {
         final List<ViewComponent> componentStack = this.getRenderContext().getComponentStack();
         if (componentStack.size() > 1) {
-            for (final var ancestor : componentStack.subList(1, componentStack.size() -1)) {
+            // 1/27/25: earlier this was originally componentStack.size() - 1 as the second argument to sublist().
+            // On examination today, it didn't make sense, because it would be chopping off the farthest ancestor from
+            // search. So I removed it, in accordance with the implementation in hasAncestor().
+            for (final var ancestor : componentStack.subList(1, componentStack.size())) {
                 if (matching.test(ancestor)) {
                     return ancestor;
                 }
@@ -79,6 +82,19 @@ public class DefaultComponentContext implements ComponentContext {
         return null;
     }
 
+    @Override
+    public boolean hasAncestor(Predicate<? super ViewComponent> matching) {
+        final List<ViewComponent> componentStack = this.getRenderContext().getComponentStack();
+        if (componentStack.size() > 1) {
+            for (final var ancestor : componentStack.subList(1, componentStack.size())) {
+                if (matching.test(ancestor)) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
     @Override
     public List<ViewComponent> getAllAncestors() {
         final List<ViewComponent> componentStack = this.getRenderContext().getComponentStack();

web-view-components/src/main/groovy/groowt/view/component/web/lib/IntrinsicHtml.groovy

@@ -5,7 +5,6 @@ import groowt.view.component.ComponentRenderException
 import groowt.view.component.context.ComponentContext
 import groowt.view.component.context.ComponentScope.TypeAndFactory
 import groowt.view.component.factory.ComponentFactory
-import groowt.view.component.web.WithHtml
 
 class IntrinsicHtml extends DelegatingWebViewComponent implements WithHtml {
 

web-view-components/src/main/groovy/groowt/view/component/web/lib/Outlet.groovy

@@ -1,6 +1,7 @@
 package groowt.view.component.web.lib
 
 import groowt.view.View
+import groowt.view.component.ComponentRenderException
 import groowt.view.component.runtime.DefaultComponentWriter
 
 class Outlet extends DelegatingWebViewComponent {
@@ -14,6 +15,11 @@ class Outlet extends DelegatingWebViewComponent {
     @Override
     protected View getDelegate() {
         return { Writer w ->
+            if (!context.hasAncestor(OutletContainer)) {
+                throw new ComponentRenderException(
+                        "<Outlet> is being used outside of a component implementing OutletContainer."
+                )
+            }
             def cw = new DefaultComponentWriter(w, context.renderContext, context)
             givenChildren.each { cw << it }
         }

web-view-components/src/main/groovy/groowt/view/component/web/lib/OutletContainer.groovy

@@ -0,0 +1,5 @@
+package groowt.view.component.web.lib
+
+import groowt.view.component.web.WebViewComponent
+
+interface OutletContainer extends WebViewComponent {}

web-view-components/src/main/groovy/groowt/view/component/web/lib/WithHtml.groovy

@@ -1,4 +1,4 @@
-package groowt.view.component.web
+package groowt.view.component.web.lib
 
 trait WithHtml {
 

web-view-components/src/test/groovy/groowt/view/component/web/lib/OutletTests.groovy

@@ -1,17 +1,35 @@
 package groowt.view.component.web.lib
 
+
+import groowt.view.component.web.WebViewComponentContext
+import groowt.view.component.web.WebViewComponentScope
 import org.junit.jupiter.api.Test
 
 class OutletTests extends AbstractWebViewComponentTests {
 
+    static final class DummyOutletContainer extends Echo implements OutletContainer {
+
+        DummyOutletContainer() {
+            super([:])
+        }
+
+    }
+
+    @Override
+    void configureContext(WebViewComponentContext context) {
+        context.configureRootScope(WebViewComponentScope) {
+            addWithNoArgConstructor(DummyOutletContainer)
+        }
+    }
+
     @Test
     void smokeScreen() {
-        doTest('<Outlet />', '')
+        doTest('<OutletTests.DummyOutletContainer><Outlet /></OutletTests.DummyOutletContainer>', '')
     }
 
     @Test
     void withChildren() {
-        doTest('<Echo items={[0, 1, 2]}><Outlet children={items} /></Echo>', '012')
+        doTest('<OutletTests.DummyOutletContainer><Echo items={[0, 1, 2]}><Outlet children={items} /></Echo></OutletTests.DummyOutletContainer>', '012')
     }
 
 }