Correctly handle exceptions from providers (close #760)

Author: henri-tremblay

core/src/main/java/org/easymock/internal/ClassProxyFactory.java

@@ -145,21 +145,22 @@ public static boolean isCallerMockInvocationHandlerInvoke(Throwable e) {
 
     @Override
     public <T> T createProxy(final Class<T> toMock, InvocationHandler handler, Method[] mockedMethods, ConstructorArgs args) {
-        Throwable kept = null;
+        RuntimeException exception = null;
         // We pick the provider we think will work
         // But we still loop around all the providers just in case we are wrong when picking but that one will eventually work
         ClassInfoProvider[] providers = isJdkClassOrWithoutPackage(toMock) ? jdkClassInfoProviders : defaultClassInfoProviders;
         for (ClassInfoProvider provider : providers) {
             try {
                 return doCreateProxy(toMock, handler, provider, mockedMethods, args);
-            } catch (Error | RuntimeException e) {
-                kept = e;
+            } catch (Throwable e) {
+                if (exception == null) {
+                    exception = new RuntimeException("Failed to mock " + toMock + " with provider " + provider, e);
+                } else {
+                    exception.addSuppressed(e);
+                }
             }
         }
-        if (kept instanceof Error) {
-            throw (Error) kept;
-        }
-        throw (RuntimeException) kept;
+        throw exception;
     }
 
     @IgnoreAnimalSniffer // It reports errors on MethodHandle.invoke

core/src/main/java/org/easymock/internal/MocksControl.java

@@ -110,10 +110,11 @@ public <T, R> R createMock(String name, Class<T> toMock, ConstructorArgs constru
                 R mock = (R) proxyFactory.createProxy(toMock, new ObjectMethodsFilter(toMock,
                     new MockInvocationHandler(this), name), mockedMethods, constructorArgs);
                 return mock;
-            } catch (NoClassDefFoundError e) {
-                if(e.getMessage().startsWith("org/objenesis")) {
+            } catch (RuntimeException e) {
+                // special case where Objenesis is not in the classpath and we try to mock classes
+                if(e.getCause() instanceof NoClassDefFoundError && e.getCause().getMessage().startsWith("org/objenesis")) {
                     throw new RuntimeExceptionWrapper(new RuntimeException(
-                        "Class mocking requires to have Objenesis library in the classpath", e));
+                        "Class mocking requires to have Objenesis library in the classpath", e.getCause()));
                 }
                 throw e;
             }

core/src/main/java/org/easymock/internal/classinfoprovider/DefaultClassInfoProvider.java

@@ -30,4 +30,8 @@ public <T> ClassLoader classLoader(Class<T> toMock) {
         return toMock.getClassLoader();
     }
 
+    @Override
+    public String toString() {
+        return getClass().getSimpleName();
+    }
 }

core/src/main/java/org/easymock/internal/classinfoprovider/JdkClassInfoProvider.java

@@ -29,4 +29,10 @@ public String classPackage(Class<?> toMock) {
     public <T> ClassLoader classLoader(Class<T> toMock) {
         return getClass().getClassLoader();
     }
+
+    @Override
+    public String toString() {
+        return getClass().getSimpleName();
+    }
+
 }

core/src/test/java/org/easymock/tests/DefaultClassInstantiatorTest.java

@@ -165,13 +165,14 @@ public void objectParamRecursion() {
     @Test
     public void constructorWithCodeLimitation() {
         Exception e = assertThrows(Exception.class, () -> createMock(ConstructorWithCodeClass.class));
-        assertEquals("Failed to instantiate org.easymock.tests.DefaultClassInstantiatorTest$ConstructorWithCodeClass's mock: ", e.getMessage());
+        assertEquals("Failed to mock class org.easymock.tests.DefaultClassInstantiatorTest$ConstructorWithCodeClass with provider DefaultClassInfoProvider", e.getMessage());
     }
 
     @Test
     public void privateConstructorLimitation() {
         Exception e = assertThrows(Exception.class, () -> createMock(PrivateConstructorClass.class));
-        assertEquals("No visible constructors in class org.easymock.tests.DefaultClassInstantiatorTest$PrivateConstructorClass", e.getMessage());
+        assertEquals("Failed to mock class org.easymock.tests.DefaultClassInstantiatorTest$PrivateConstructorClass with provider DefaultClassInfoProvider", e.getMessage());
+        assertEquals("No visible constructors in class org.easymock.tests.DefaultClassInstantiatorTest$PrivateConstructorClass", e.getCause().getMessage());
     }
 
     @Test

core/src/test/java/org/easymock/tests2/PartialMockingTest.java

@@ -109,7 +109,8 @@ public void testPartialMock_InvalidParams() {
     public void testPartialMock_ExceptionInConstructor() {
         RuntimeException ex = assertThrows(RuntimeException.class,
             () -> createMockBuilder(ArrayList.class).withConstructor(-5).createMock());
-        Assertions.assertEquals("Failed to instantiate mock calling constructor: Exception in constructor", ex.getMessage());
+        Assertions.assertEquals("Failed to mock class java.util.ArrayList with provider JdkClassInfoProvider", ex.getMessage());
+        Assertions.assertEquals("Failed to instantiate mock calling constructor: Exception in constructor", ex.getCause().getMessage());
     }
 
     @Test

test-nodeps/src/test/java/org/itests/DependencyTest.java

@@ -48,14 +48,9 @@ public void testInterfaceMocking() {
 
     @Test
     public void testClassMocking() {
-        try {
-            createMock(DependencyTest.class);
-            fail("Should throw an exception due to a NoClassDefFoundError");
-        } catch (RuntimeException e) {
-            assertEquals("Class mocking requires to have Objenesis library in the classpath", e
-                    .getMessage());
-            assertTrue(e.getCause() instanceof NoClassDefFoundError);
-        }
+        RuntimeException e = assertThrows(RuntimeException.class, () -> createMock(DependencyTest.class));
+        assertEquals("Class mocking requires to have Objenesis library in the classpath", e.getMessage());
+        assertTrue(e.getCause() instanceof NoClassDefFoundError);
     }
 
     @Test
@@ -69,23 +64,14 @@ public void testInterfaceMockingSupport() {
 
     @Test
     public void testClassMockingSupport() {
-        try {
-            support.createMock(DependencyTest.class);
-            fail("Should throw an exception due to a NoClassDefFoundError");
-        } catch (RuntimeException e) {
-            assertEquals("Class mocking requires to have Objenesis library in the classpath", e
-                    .getMessage());
-            assertTrue(e.getCause() instanceof NoClassDefFoundError);
-        }
+        RuntimeException e = assertThrows(RuntimeException.class, () -> support.createMock(DependencyTest.class));
+        assertEquals("Class mocking requires to have Objenesis library in the classpath", e.getMessage());
+        assertTrue(e.getCause() instanceof NoClassDefFoundError);
     }
 
     @Test
     public void testStillNoClassDefFoundErrorWhenSomeOtherClassIsMissing() {
-        try {
-            support.createMock(Main.class);
-            fail("Should throw an exception due to a NoClassDefFoundError");
-        } catch (NoClassDefFoundError e) {
-            assertEquals("org/depends/Dependency", e.getMessage());
-        }
+        NoClassDefFoundError e = assertThrows(NoClassDefFoundError.class, () -> support.createMock(Main.class));
+        assertEquals("org/depends/Dependency", e.getMessage());
     }
 }