test IndyProxyHelper

Author: SylvainJuge

javaagent-bootstrap/src/main/java/io/opentelemetry/javaagent/bootstrap/IndyProxy.java

@@ -5,9 +5,7 @@
 
 package io.opentelemetry.javaagent.bootstrap;
 
-/**
- * Interface added to indy proxies to allow unwrapping the proxy object
- */
+/** Interface added to indy proxies to allow unwrapping the proxy object */
 public interface IndyProxy {
 
   /**

javaagent-bootstrap/src/main/java/io/opentelemetry/javaagent/bootstrap/IndyProxyHelper.java

@@ -15,21 +15,21 @@ private IndyProxyHelper() {}
    * @param <T> type of object to return
    * @param o object to unwrap
    * @param type expected object type
-   * @return unwrapped proxy instance or the original object (if not a proxy) cast to the expected type
-   * @throws IllegalArgumentException if the provided object the proxied object can't be cast to the expected type
-   *
+   * @return unwrapped proxy instance or the original object (if not a proxy) cast to the expected
+   *     type
+   * @throws IllegalArgumentException if the provided object the proxied object can't be cast to the
+   *     expected type
    */
   public static <T> T unwrapIfNeeded(Object o, Class<T> type) {
-    if (type.isAssignableFrom(o.getClass())) {
-      return type.cast(o);
-    }
-
     if (o instanceof IndyProxy) {
       Object delegate = ((IndyProxy) o).__getIndyProxyDelegate();
       if (type.isAssignableFrom(delegate.getClass())) {
         return type.cast(delegate);
       }
     }
+    if (type.isAssignableFrom(o.getClass())) {
+      return type.cast(o);
+    }
 
     throw new IllegalArgumentException("unexpected object type");
   }

javaagent-bootstrap/src/test/java/io/opentelemetry/javaagent/bootstrap/IndyProxyHelperTest.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.javaagent.bootstrap;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+class IndyProxyHelperTest {
+
+  @Test
+  void wrongType() {
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> IndyProxyHelper.unwrapIfNeeded("", Integer.class));
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> IndyProxyHelper.unwrapIfNeeded(proxy(""), Integer.class));
+  }
+
+  @Test
+  void unwrap() {
+
+    // no wrapping
+    Number number = IndyProxyHelper.unwrapIfNeeded(42, Number.class);
+    assertThat(number).isEqualTo(42);
+
+    // unwrap needed
+    String string = IndyProxyHelper.unwrapIfNeeded(proxy("hello"), String.class);
+    assertThat(string).isEqualTo("hello");
+  }
+
+  private static IndyProxy proxy(Object delegate) {
+    return () -> delegate;
+  }
+}