Add ClassPathScanner tests

Signed-off-by: Stephen Kitt <skitt@redhat.com>

src/test/java/org/opendaylight/infrautils/inject/tests/ClassPathScannerTest.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright © 2018 Red Hat, Inc. and others.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.infrautils.inject.tests;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.CALLS_REAL_METHODS;
+import static org.mockito.Mockito.mock;
+
+import com.google.inject.Binder;
+import com.google.inject.binder.AnnotatedBindingBuilder;
+import com.google.inject.binder.ScopedBindingBuilder;
+import java.util.HashMap;
+import java.util.Map;
+import javax.annotation.Nullable;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mockito;
+import org.opendaylight.infrautils.inject.ClassPathScanner;
+
+public class ClassPathScannerTest {
+    private final TestBinder testBinder = mock(TestBinder.class, Mockito.CALLS_REAL_METHODS);
+
+    @Before
+    public void setup() {
+        new ClassPathScanner("org.opendaylight.infrautils.inject.tests").bind(testBinder,
+            ClassPathScannerTestTopInterface.class);
+    }
+
+    @Test
+    public void verifyImplementationBinding() {
+        assertEquals(ClassPathScannerTestImplementation.class,
+            testBinder.getImplementation(ClassPathScannerTestTopInterface.class));
+    }
+
+    private abstract static class TestBinder implements Binder {
+        private Map<Class<?>, Class<?>> bindings;
+
+        private <T> void storeBinding(Class<T> type, Class<? extends T> implementation) {
+            if (bindings == null) {
+                bindings = new HashMap<>();
+            }
+            bindings.put(type, implementation);
+        }
+
+        <T> Class<? extends T> getImplementation(Class<T> type) {
+            return (Class<? extends T>) bindings.get(type);
+        }
+
+        @Override
+        public <T> AnnotatedBindingBuilder<T> bind(Class<T> type) {
+            TestAnnotatedBindingBuilder builder = mock(TestAnnotatedBindingBuilder.class, CALLS_REAL_METHODS);
+            builder.setType(type);
+            builder.setBinder(this);
+            return builder;
+        }
+
+        private abstract static class TestAnnotatedBindingBuilder<T> implements AnnotatedBindingBuilder<T> {
+            private Class<T> type;
+            private TestBinder binder;
+
+            @Nullable
+            @Override
+            public ScopedBindingBuilder to(Class<? extends T> implementation) {
+                binder.storeBinding(type, implementation);
+                return null;
+            }
+
+            void setType(Class<T> type) {
+                this.type = type;
+            }
+
+            void setBinder(TestBinder binder) {
+                this.binder = binder;
+            }
+        }
+    }
+}

src/test/java/org/opendaylight/infrautils/inject/tests/ClassPathScannerTestImplementation.java

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+/*
+ * Copyright © 2018 Red Hat, Inc. and others.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.infrautils.inject.tests;
+
+import javax.inject.Singleton;
+
+@Singleton
+public class ClassPathScannerTestImplementation implements ClassPathScannerTestTopInterface {
+}

src/test/java/org/opendaylight/infrautils/inject/tests/ClassPathScannerTestTopInterface.java

@@ -0,0 +1,11 @@
+/*
+ * Copyright © 2018 Red Hat, Inc. and others.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.infrautils.inject.tests;
+
+public interface ClassPathScannerTestTopInterface {
+}