diff --git a/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.xtend b/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.xtend
index ee358b24b3d..381fdd37aab 100644
--- a/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.xtend
+++ b/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.xtend
@@ -80,7 +80,7 @@ class AccessorsCompilerTest extends AbstractXtendCompilerTest {
 	
 	@Test
 	def void testCannotOverrideWithConflictingReturnType() {
-		file('''
+		val source = '''
 			import org.eclipse.xtend.lib.annotations.Accessors
 			class Foo {
 				def String getFoo() {"foo"}
@@ -89,7 +89,10 @@ class AccessorsCompilerTest extends AbstractXtendCompilerTest {
 			class Bar extends Foo {
 				@Accessors int foo
 			}
-		''').assertError(XtendPackage.Literals.XTEND_FIELD, INCOMPATIBLE_RETURN_TYPE, "incompatible", "getFoo")
+		'''
+		file(source).assertError(XtendPackage.Literals.XTEND_FIELD, INCOMPATIBLE_RETURN_TYPE,
+			source.indexOf("@Accessors int foo"), "@Accessors int foo".length,
+			"incompatible", "getFoo")
 	}
 	
 	@Test
diff --git a/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/validation/OverrideValidationTest.java b/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/validation/OverrideValidationTest.java
index 4456e9f4d23..a48f9380a6c 100644
--- a/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/validation/OverrideValidationTest.java
+++ b/org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/validation/OverrideValidationTest.java
@@ -805,8 +805,11 @@ public void testClassMustBeAbstract_06() throws Exception {
 	}
 
 	@Test public void testInterfaceIncompatibleReturnType_0() throws Exception {
-		XtendInterface xtendInterface = interfaze("interface Foo extends test.SuperInterface { override Boolean string() }");
-		helper.assertError(xtendInterface.getMembers().get(0), XTEND_FUNCTION, INCOMPATIBLE_RETURN_TYPE);
+		var source = "interface Foo extends test.SuperInterface { override Boolean string() }";
+		XtendInterface xtendInterface = interfaze(source);
+		helper.assertError(xtendInterface.getMembers().get(0), XTEND_FUNCTION, INCOMPATIBLE_RETURN_TYPE,
+				source.indexOf("Boolean"), "Boolean".length(),
+				"return type is incompatible with", "string()");
 	}
 
 	@Test public void testInterfaceIncompatibleReturnType_1() throws Exception {
@@ -815,8 +818,11 @@ public void testClassMustBeAbstract_06() throws Exception {
 	}
 
 	@Test public void testInterfaceIncompatibleReturnType_2() throws Exception {
-		XtendInterface xtendInterface = interfaze("interface Foo extends test.SomeInterface { override void foo() }");
-		helper.assertError(xtendInterface.getMembers().get(0), XTEND_FUNCTION, INCOMPATIBLE_RETURN_TYPE);
+		var source = "interface Foo extends test.SomeInterface { override void foo() }";
+		XtendInterface xtendInterface = interfaze(source);
+		helper.assertError(xtendInterface.getMembers().get(0), XTEND_FUNCTION, INCOMPATIBLE_RETURN_TYPE,
+				source.indexOf("void"), "void".length(),
+				"return type is incompatible with", "foo()");
 	}
 
 	@Test public void testInterfaceIncompatibleGenericReturnType_0() throws Exception {
@@ -825,8 +831,10 @@ public void testClassMustBeAbstract_06() throws Exception {
 	}
 
 	@Test public void testInterfaceIncompatibleGenericReturnType_1() throws Exception {
-		XtendInterface xtendInterface = interfaze("interface Foo extends test.SuperInterface { override java.util.List<Object> returnsListString() }");
-		helper.assertError(xtendInterface.getMembers().get(0), XTEND_FUNCTION, INCOMPATIBLE_RETURN_TYPE);
+		var source = "interface Foo extends test.SuperInterface { override java.util.List<Object> returnsListString() }";
+		XtendInterface xtendInterface = interfaze(source);
+		helper.assertError(xtendInterface.getMembers().get(0), XTEND_FUNCTION, INCOMPATIBLE_RETURN_TYPE,
+				source.indexOf("java.util.List<Object>"), "java.util.List<Object>".length());
 	}
 
 	@Test public void testInterfaceIncompatibleGenericReturnType_2() throws Exception {
diff --git a/org.eclipse.xtend.core.tests/xtend-gen/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.java b/org.eclipse.xtend.core.tests/xtend-gen/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.java
index 2e9d058eab9..e8013a9ea5a 100644
--- a/org.eclipse.xtend.core.tests/xtend-gen/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.java
+++ b/org.eclipse.xtend.core.tests/xtend-gen/org/eclipse/xtend/core/tests/compiler/AccessorsCompilerTest.java
@@ -170,7 +170,10 @@ public void testCannotOverrideWithConflictingReturnType() {
       _builder.newLine();
       _builder.append("}");
       _builder.newLine();
-      this._validationTestHelper.assertError(this.file(_builder.toString()), XtendPackage.Literals.XTEND_FIELD, IssueCodes.INCOMPATIBLE_RETURN_TYPE, "incompatible", "getFoo");
+      final String source = _builder.toString();
+      this._validationTestHelper.assertError(this.file(source), XtendPackage.Literals.XTEND_FIELD, IssueCodes.INCOMPATIBLE_RETURN_TYPE, 
+        source.indexOf("@Accessors int foo"), "@Accessors int foo".length(), 
+        "incompatible", "getFoo");
     } catch (Throwable _e) {
       throw Exceptions.sneakyThrow(_e);
     }