/*
    * MIT License
    * Copyright (c) 2006-2025 JMockit developers
    * See LICENSE file for full license text.
    */
   package mockit.internal;
   
   import static org.junit.jupiter.api.Assertions.assertNotNull;
   import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import mockit.asm.classes.ClassReader;
  
  import org.junit.jupiter.api.Test;
  
  final class ClassFileTest {
  
      @Test
      void createClassReaderWithValidClass() {
          ClassLoader cl = ClassFileTest.class.getClassLoader();
          ClassReader reader = ClassFile.createClassReader(cl, "mockit/internal/ClassFile");
          assertNotNull(reader);
      }
  
      @Test
      void createClassReaderWithNonExistentClassReturnsNull() {
          ClassLoader cl = ClassFileTest.class.getClassLoader();
          ClassReader reader = ClassFile.createClassReader(cl, "com/example/DoesNotExist");
          // Should return null when class file not found
          assertTrue(reader == null);
      }
  
      @Test
      void createReaderOrGetFromCacheForKnownClass() {
          ClassReader reader = ClassFile.createReaderOrGetFromCache(String.class);
          assertNotNull(reader);
      }
  
      @Test
      void createReaderOrGetFromCacheReturnsCachedReader() {
          // Call twice to test caching
          ClassReader reader1 = ClassFile.createReaderOrGetFromCache(Integer.class);
          ClassReader reader2 = ClassFile.createReaderOrGetFromCache(Integer.class);
          assertNotNull(reader1);
          assertNotNull(reader2);
      }
  
      @Test
      void createReaderOrGetFromCacheForNonCachedClass() {
          // Use a class that's unlikely to be in CachedClassfiles (test-only class)
          ClassReader reader = ClassFile.createReaderOrGetFromCache(ClassFileTest.class);
          assertNotNull(reader);
          // Call again to hit the CLASS_FILES cache
          ClassReader reader2 = ClassFile.createReaderOrGetFromCache(ClassFileTest.class);
          assertNotNull(reader2);
      }
  
      @Test
      void getClassFileByNameForKnownClass() {
          byte[] bytes = ClassFile.getClassFile("java/lang/String");
          assertNotNull(bytes);
          assertTrue(bytes.length > 0);
      }
  
      @Test
      void getClassFileByClassForKnownClass() {
          byte[] bytes = ClassFile.getClassFile(String.class);
          assertNotNull(bytes);
          assertTrue(bytes.length > 0);
      }
  
      @Test
      void getClassFileByLoaderAndNameForKnownClass() {
          byte[] bytes = ClassFile.getClassFile(ClassFileTest.class.getClassLoader(), "mockit/internal/ClassFile");
          assertNotNull(bytes);
          assertTrue(bytes.length > 0);
      }
  
      @Test
      void readBytesFromClassFileByName() {
          byte[] bytes = ClassFile.readBytesFromClassFile("mockit/internal/ClassFile");
          assertNotNull(bytes);
          assertTrue(bytes.length > 0);
      }
  
      @Test
      void readBytesFromClassFileByClass() {
          byte[] bytes = ClassFile.readBytesFromClassFile(ClassFileTest.class);
          assertNotNull(bytes);
          assertTrue(bytes.length > 0);
      }
  
      @Test
      void readBytesFromClassFileThrowsForUnknownClass() {
          assertThrows(RuntimeException.class, () -> ClassFile.readBytesFromClassFile("com/example/DoesNotExist"));
      }
  
      @Test
      void notFoundExceptionHasCorrectMessage() {
         try {
             ClassFile.readBytesFromClassFile("com/example/Missing");
         } catch (RuntimeException e) {
             // Expected
         }
     }
 
     @Test
     void createReaderFromLastRedefinitionIfAny() {
         ClassReader reader = ClassFile.createReaderFromLastRedefinitionIfAny(String.class);
         assertNotNull(reader);
     }
 }