✨ Add access to parameter annotations in the parameter injector

CHANGELOG.md

@@ -23,6 +23,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
  - Allow command argument names to include `_` and `-` ([#186](https://github.com/Incendo/cloud/pull/186))
  - Make it easier to use translatable components with MinecraftHelp ([#197](https://github.com/Incendo/cloud/pull/197))
  - Show "No result for query" when a multi-help topic is empty
+ - Use the method+field annotation accessor rather than the method accessor when injecting method parameters
 
 ### Deprecated
  - Description, and everything using Description directly ([#207](https://github.com/Incendo/cloud/pull/207))

cloud-annotations/src/main/java/cloud/commandframework/annotations/MethodCommandExecutionHandler.java

@@ -92,7 +92,7 @@ class MethodCommandExecutionHandler<C> implements CommandExecutionHandler<C> {
                     final Optional<?> value = this.injectorRegistry.getInjectable(
                             parameter.getType(),
                             commandContext,
-                            this.annotationAccessor
+                            AnnotationAccessor.of(AnnotationAccessor.of(parameter), this.annotationAccessor)
                     );
                     if (value.isPresent()) {
                         arguments.add(value.get());

cloud-core/src/main/java/cloud/commandframework/annotations/AnnotationAccessor.java

@@ -60,6 +60,18 @@ public interface AnnotationAccessor {
         return new AnnotatedElementAccessor(element);
     }
 
+    /**
+     * Get a {@link AnnotationAccessor} instance that delegates to multiple {@link AnnotatedElement} instances.
+     * The first accessor that provides a requested annotation will always be used
+     *
+     * @param accessors The accessor to delegate to
+     * @return Annotation accessor that delegates to the given accessors (using their natural ordering)
+     * @since 1.4.0
+     */
+    static @NonNull AnnotationAccessor of(final @NonNull AnnotationAccessor@NonNull... accessors) {
+        return new MultiDelegateAnnotationAccessor(accessors);
+    }
+
     /**
      * Get an annotation instance, if it's present. If the annotation
      * isn't available, this will return {@code null}

cloud-core/src/main/java/cloud/commandframework/annotations/MultiDelegateAnnotationAccessor.java

@@ -0,0 +1,64 @@
+//
+// MIT License
+//
+// Copyright (c) 2020 Alexander Söderberg & Contributors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+package cloud.commandframework.annotations;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+import java.lang.annotation.Annotation;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+
+final class MultiDelegateAnnotationAccessor implements AnnotationAccessor {
+
+    private final AnnotationAccessor[] accessors;
+
+    MultiDelegateAnnotationAccessor(final @NonNull AnnotationAccessor@NonNull... accessors) {
+        this.accessors = accessors;
+    }
+
+    @Override
+    public <A extends Annotation> @Nullable A annotation(@NonNull final Class<A> clazz) {
+        A instance = null;
+        for (final AnnotationAccessor annotationAccessor : accessors) {
+            instance = annotationAccessor.annotation(clazz);
+            if (instance != null) {
+                break;
+            }
+        }
+        return instance;
+    }
+
+    @Override
+    public @NonNull Collection<@NonNull Annotation> annotations() {
+        final List<Annotation> annotationList = new LinkedList<>();
+        for (final AnnotationAccessor annotationAccessor : accessors) {
+            annotationList.addAll(annotationAccessor.annotations());
+        }
+        return Collections.unmodifiableCollection(annotationList);
+    }
+
+}

cloud-core/src/main/java/cloud/commandframework/annotations/injection/ParameterInjector.java

@@ -44,7 +44,7 @@ public interface ParameterInjector<C, T> {
      * annotated method. If the injector cannot (or shouldn't) create a value, it is free to return {@code null}.
      *
      * @param context            Command context that is requesting the injection
-     * @param annotationAccessor Annotation accessor proxying the method which the value is being injected into
+     * @param annotationAccessor Annotation accessor proxying the method and parameter which the value is being injected into
      * @return The value, if it could be created. Else {@code null}, in which case no value will be injected
      *         by this particular injector
      */

cloud-core/src/test/java/cloud/commandframework/AnnotationAccessorTest.java

@@ -0,0 +1,64 @@
+//
+// MIT License
+//
+// Copyright (c) 2020 Alexander Söderberg & Contributors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+package cloud.commandframework;
+
+import cloud.commandframework.annotations.AnnotationAccessor;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import java.lang.reflect.Method;
+import java.lang.reflect.Parameter;
+
+public class AnnotationAccessorTest {
+
+    @Qualifier("method")
+    public static void annotatedMethod(@Qualifier("parameter") final String parameter) {
+    }
+
+    @Test
+    void testQualifierResolutionOrder() throws Exception {
+        final Method method = AnnotationAccessorTest.class.getMethod("annotatedMethod", String.class);
+        final Parameter parameter = method.getParameters()[0];
+        final AnnotationAccessor accessor = AnnotationAccessor.of(
+                AnnotationAccessor.of(parameter),
+                AnnotationAccessor.of(method)
+        );
+        final Qualifier qualifier = accessor.annotation(Qualifier.class);
+        Assertions.assertNotNull(qualifier);
+        Assertions.assertEquals("parameter", qualifier.value());
+    }
+
+    @Target({ElementType.PARAMETER, ElementType.METHOD})
+    @Retention(RetentionPolicy.RUNTIME)
+    private @interface Qualifier {
+
+        String value();
+
+    }
+
+}

cloud-core/src/test/java/cloud/commandframework/ParameterInjectorRegistryTest.java

@@ -48,7 +48,7 @@ public class ParameterInjectorRegistryTest {
     private Injector injector;
 
     @BeforeEach
-    public void setup() {
+    void setup() {
         this.commandSender = new TestCommandSender();
         this.commandManager = new TestCommandManager();
         this.commandContextFactory = new StandardCommandContextFactory<>();
@@ -63,7 +63,7 @@ public class ParameterInjectorRegistryTest {
     }
 
     @Test
-    public void testSimpleInjection() {
+    void testSimpleInjection() {
         Assertions.assertEquals(INJECTED_INTEGER, parameterInjectorRegistry.getInjectable(
                 Integer.class,
                 this.createContext(),
@@ -72,7 +72,7 @@ public class ParameterInjectorRegistryTest {
     }
 
     @Test
-    public void testGuiceInjection() {
+    void testGuiceInjection() {
         this.parameterInjectorRegistry.registerInjectionService(GuiceInjectionService.create(this.injector));
         Assertions.assertEquals(TestModule.INJECTED_INTEGER, parameterInjectorRegistry.getInjectable(
                 Integer.class,
@@ -82,7 +82,7 @@ public class ParameterInjectorRegistryTest {
     }
 
     @Test
-    public void testNonExistentInjection() {
+    void testNonExistentInjection() {
         Assertions.assertNull(parameterInjectorRegistry.getInjectable(
                 String.class,
                 this.createContext(),