(issue 20): Handle top-level nested test classes (#22)

* (issue 20): fix issue where spring integration tests that do not declare any @MockInBean fields throw an exception due to applicableTestContext being null

* handle top-level nested test classes

---------

Co-authored-by: jamesforward <[email protected]>

README.MD

@@ -86,7 +86,7 @@ Simply include the maven dependency (from central maven) to start using @MockInB
 <dependency>
   <groupId>com.teketik</groupId>
   <artifactId>mock-in-bean</artifactId>
-  <version>boot2-v1.5.1</version>
+  <version>boot2-v1.5.2</version>
   <scope>test</scope>
 </dependency>
 ```

pom.xml

@@ -5,7 +5,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.teketik</groupId>
     <artifactId>mock-in-bean</artifactId>
-    <version>boot2-v1.5.1</version>
+    <version>boot2-v1.5.2</version>
     <name>Mock in Bean</name>
     <description>Surgically Inject Mockito Mock/Spy in Spring Beans</description>
     <url>https://github.com/antoinemeyer/mock-in-bean</url>

src/main/java/com/teketik/test/mockinbean/MockInBeanTestExecutionListener.java

@@ -148,7 +148,8 @@ private Class<?> resolveTestClass(Class<?> candidate) {
     }
 
     private boolean isNestedTestClass(Class<?> candidate) {
-        return AnnotationUtils.isAnnotationDeclaredLocally(Nested.class, candidate);
+        return AnnotationUtils.isAnnotationDeclaredLocally(Nested.class, candidate)
+                && candidate.getEnclosingClass() != null;
     }
 
 }

src/test/java/com/teketik/test/mockinbean/test/NestedTopLevelTest.java

@@ -0,0 +1,13 @@
+package com.teketik.test.mockinbean.test;
+
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+@Nested
+class NestedTopLevelTest extends BaseTest {
+
+    @Test
+    public void test() {
+    }
+
+}