alternative to #1762: fix: a NPE in CtTypeImpl#isSameParameter in noclasspath

src/main/java/spoon/support/reflect/declaration/CtTypeImpl.java

@@ -760,28 +760,31 @@ private boolean isSameParameter(CtMethod<?> method, CtTypeReference<?> ctParamet
 			}
 		}
 		if (expectedType instanceof CtTypeParameterReference && ctParameterType instanceof CtTypeParameterReference) {
-			// Check if Object or extended.
+			// both types are generic
 			if (!ctParameterType.equals(expectedType)) {
 				return false;
 			}
 		} else if (expectedType instanceof CtTypeParameterReference) {
-			if (!ctParameterType.isSubtypeOf(factory.Type().createReference(expectedType.getActualClass()))) {
+			// expectedType type is generic, ctParameterType is real type
+			if (!expectedType.getTypeErasure().getQualifiedName().equals(ctParameterType.getQualifiedName())) {
 				return false;
 			}
 		} else if (ctParameterType instanceof CtTypeParameterReference) {
+			// ctParameterType is generic, expectedType type is real type
 			CtTypeParameter declaration = (CtTypeParameter) ctParameterType.getDeclaration();
-			if (declaration.getSuperclass() instanceof CtIntersectionTypeReference) {
+			if (declaration != null && declaration.getSuperclass() instanceof CtIntersectionTypeReference) {
 				for (CtTypeReference<?> ctTypeReference : declaration.getSuperclass().asCtIntersectionTypeReference().getBounds()) {
 					if (ctTypeReference.equals(expectedType)) {
 						return true;
 					}
 				}
-			} else if (declaration.getSuperclass() != null) {
+			} else if (declaration != null && declaration.getSuperclass() != null) {
 				return declaration.getSuperclass().equals(expectedType);
 			} else {
 				return getFactory().Type().objectType().equals(expectedType);
 			}
 		} else if (!expectedType.getQualifiedName().equals(ctParameterType.getQualifiedName())) {
+			// both are real types
 			return false;
 		}
 		return true;

src/test/java/spoon/test/invocations/InvocationTest.java

@@ -3,20 +3,25 @@
 import org.junit.Test;
 import spoon.Launcher;
 import spoon.SpoonAPI;
+import spoon.reflect.CtModel;
 import spoon.reflect.code.CtInvocation;
 import spoon.reflect.code.CtTypeAccess;
 import spoon.reflect.declaration.CtClass;
+import spoon.reflect.declaration.CtExecutable;
 import spoon.reflect.declaration.CtMethod;
 import spoon.reflect.factory.Factory;
 import spoon.reflect.reference.CtExecutableReference;
 import spoon.reflect.visitor.filter.AbstractFilter;
+import spoon.reflect.visitor.filter.TypeFilter;
 import spoon.test.invocations.testclasses.Bar;
 import spoon.test.invocations.testclasses.Foo;
 
 import java.util.List;
+import java.util.stream.Collectors;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static spoon.testing.utils.ModelUtils.build;
@@ -58,4 +63,21 @@ public void testTargetNullForStaticMethod() throws Exception {
 			fail();
 		}
 	}
+
+	@Test
+	public void testIssue1753() {
+		final Launcher launcher = new Launcher();
+		launcher.getEnvironment().setNoClasspath(true);
+		launcher.addInputResource("./src/test/resources/noclasspath/elasticsearch1753");
+
+		final CtModel model = launcher.buildModel();
+		final List<CtExecutable> executables =
+				model.getElements(new TypeFilter<>(CtExecutable.class))
+						.stream()
+						.filter(i -> i.getPosition().getLine() == 190)
+						.collect(Collectors.toList());
+		assertEquals(1, executables.size());
+		final CtExecutable exe = executables.get(0);
+		assertNotNull(exe.getReference().getDeclaration());
+	}
 }