Bug 381443 - [compiler][null] Allow parameter widening from @NonNull to

unannotated

3 files changed, 42 insertions, 39 deletions

diff --git a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java
index 0912731..e2fd4e6 100644
--- a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java
+++ b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java
@@ -25,6 +25,7 @@
  *								bug 374605 - Unreasonable warning for enum-based switch statements
  *								bug 375366 - ECJ ignores unusedParameterIncludeDocCommentReference unless enableJavadoc option is set
  *								bug 388281 - [compiler][null] inheritance of null annotations as an option
+ *								bug 381443 - [compiler][null] Allow parameter widening from @NonNull to unannotated
  *******************************************************************************/
 package org.eclipse.jdt.core.tests.compiler.regression;
 
@@ -12633,12 +12634,7 @@ public void test313_warn_options() {
 		"	                     ^^^^^^\n" + 
 		"Missing nullable annotation: inherited method from X declares this parameter as @Nullable\n" + 
 		"----------\n" + 
-		"3. WARNING in ---OUTPUT_DIR_PLACEHOLDER---/p/X.java (at line 9)\n" + 
-		"	@Nullable Object foo(Object o, Object o2) { return null; }\n" + 
-		"	                               ^^^^^^\n" + 
-		"Missing non-null annotation: inherited method from X declares this parameter as @NonNull\n" + 
-		"----------\n" + 
-		"3 problems (3 warnings)", 
+		"2 problems (2 warnings)", 
 		true);
 }
 
@@ -12682,12 +12678,7 @@ public void test314_warn_options() {
 		"	                     ^^^^^^\n" + 
 		"Missing nullable annotation: inherited method from X declares this parameter as @Nullable\n" + 
 		"----------\n" + 
-		"3. ERROR in ---OUTPUT_DIR_PLACEHOLDER---/p/X.java (at line 9)\n" + 
-		"	@Nullable Object foo(Object o, Object o2) { return null; }\n" + 
-		"	                               ^^^^^^\n" + 
-		"Missing non-null annotation: inherited method from X declares this parameter as @NonNull\n" + 
-		"----------\n" + 
-		"3 problems (3 errors)", 
+		"2 problems (2 errors)", 
 		true);
 }
 
@@ -13673,12 +13664,7 @@ public void testBug375366c() throws IOException {
 			"	                     ^^^^^^\n" + 
 			"Missing nullable annotation: inherited method from X declares this parameter as @Nullable\n" + 
 			"----------\n" + 
-			"3. ERROR in ---OUTPUT_DIR_PLACEHOLDER---/p/X.java (at line 9)\n" + 
-			"	@Nullable Object foo(Object o, Object o2) { return null; }\n" + 
-			"	                               ^^^^^^\n" + 
-			"Missing non-null annotation: inherited method from X declares this parameter as @NonNull\n" + 
-			"----------\n" + 
-			"3 problems (3 errors)", 
+			"2 problems (2 errors)", 
 			false/*don't flush*/);
 }
 
diff --git a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/NullAnnotationTest.java b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/NullAnnotationTest.java
index 4997d50..fc2e484 100644
--- a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/NullAnnotationTest.java
+++ b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/NullAnnotationTest.java
@@ -920,10 +920,10 @@ public void test_parameter_specification_inheritance_008() {
 	options.put(JavaCore.COMPILER_PB_NULL_UNCHECKED_CONVERSION, JavaCore.ERROR);
 	runConformTestWithLibs(
 		new String[] {
-			"IX.java",
+			"X.java",
 			"import org.eclipse.jdt.annotation.*;\n" +
-			"public interface IX {\n" +
-			"    void printObject(@NonNull Object o);\n" +
+			"public class X {\n" +
+			"    void printObject(@NonNull Object o) { System.out.print(o.toString()); }\n" +
 			"}\n"
 		},
 		null /*customOptions*/,
@@ -931,26 +931,25 @@ public void test_parameter_specification_inheritance_008() {
 	runNegativeTestWithLibs(
 		false, // don't flush
 		new String[] {
-			"X.java",
-			"public class X implements IX {\n" +
-			"    public void printObject(Object o) { System.out.print(o.toString()); }\n" +
+			"XSub.java",
+			"public class XSub extends X {\n" +
+			"    @Override\n" +
+			"    public void printObject(Object o) { super.printObject(o); }\n" +
 			"}\n",
 			"M.java",
 			"public class M{\n" +
-			"    void foo(IX x, Object o) {\n" +
+			"    void foo(X x, Object o) {\n" +
 			"        x.printObject(o);\n" +
 			"    }\n" +
 			"}\n"
 		},
 		options,
 		"----------\n" +
-		// additional error:
-		"1. ERROR in X.java (at line 2)\n" +
-		"	public void printObject(Object o) { System.out.print(o.toString()); }\n" +
-		"	                        ^^^^^^\n" +
-		"Missing non-null annotation: inherited method from IX declares this parameter as @NonNull\n" +
+		"1. ERROR in XSub.java (at line 3)\n" +
+		"	public void printObject(Object o) { super.printObject(o); }\n" +
+		"	                                                      ^\n" +
+		"Null type safety: The expression of type Object needs unchecked conversion to conform to \'@NonNull Object\'\n" +
 		"----------\n" +
-		// main error:
 		"----------\n" +
 		"1. ERROR in M.java (at line 3)\n" +
 		"	x.printObject(o);\n" +
@@ -1114,18 +1113,14 @@ public void test_parameter_specification_inheritance_013() {
 		"	public @Nullable String getString(String s1, @NonNull String s2, @NonNull String s3) {\n" +
 		"	       ^^^^^^^^^^^^^^^^\n" +
 		"The return type is incompatible with the @NonNull return from IY.getString(String, String, String)\n" +
+		// no problem regarding s1: widening @NonNull to unannotated
 		"----------\n" +
 		"2. ERROR in p1\\Y.java (at line 5)\n" +
 		"	public @Nullable String getString(String s1, @NonNull String s2, @NonNull String s3) {\n" +
-		"	                                  ^^^^^^\n" +
-		"Missing non-null annotation: inherited method from IY declares this parameter as @NonNull\n" +
-		"----------\n" +
-		"3. ERROR in p1\\Y.java (at line 5)\n" +
-		"	public @Nullable String getString(String s1, @NonNull String s2, @NonNull String s3) {\n" +
 		"	                                             ^^^^^^^^^^^^^^^\n" +
 		"Illegal redefinition of parameter s2, inherited method from X declares this parameter as @Nullable\n" +
 		"----------\n" +
-		"4. ERROR in p1\\Y.java (at line 5)\n" +
+		"3. ERROR in p1\\Y.java (at line 5)\n" +
 		"	public @Nullable String getString(String s1, @NonNull String s2, @NonNull String s3) {\n" +
 		"	                                                                 ^^^^^^^^^^^^^^^\n" +
 		"Illegal redefinition of parameter s3, inherited method from IY declares this parameter as @Nullable\n" +
@@ -1200,6 +1195,29 @@ public void test_parameter_specification_inheritance_014() {
 		"The method getString3(String) from X cannot implement the corresponding method from IY due to incompatible nullness constraints\n" +
 		"----------\n");
 }
+// a method relaxes the parameter null specification from @NonNull to un-annotated
+// see https://bugs.eclipse.org/381443
+public void test_parameter_specification_inheritance_015() {
+	runConformTest(
+		new String[] {
+			"X.java",
+			"import org.eclipse.jdt.annotation.*;\n" +
+			"public class X {\n" +
+			"    void foo(@NonNull String s) { System.out.println(s); }\n" +
+			"}\n",
+			"XSub.java",
+			"import org.eclipse.jdt.annotation.*;\n" +
+			"public class XSub extends X {\n" +
+			"    public void foo(String s) { if (s != null) super.foo(s); }\n" +
+			"    void bar() { foo(null); }\n" +
+			"}\n"
+		},
+		"",
+	    this.LIBS,
+	    false/*shouldFlush*/,
+	    null/*vmArgs*/);
+}
+
 // a nullable return value is dereferenced without a check
 public void test_nullable_return_001() {
 	runNegativeTestWithLibs(
diff --git a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/lookup/ImplicitNullAnnotationVerifier.java b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/lookup/ImplicitNullAnnotationVerifier.java
index 908ad32..664455c 100644
--- a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/lookup/ImplicitNullAnnotationVerifier.java
+++ b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/lookup/ImplicitNullAnnotationVerifier.java
@@ -319,10 +319,9 @@ public class ImplicitNullAnnotationVerifier {
 					} else {
 						scope.problemReporter().cannotImplementIncompatibleNullness(currentMethod, inheritedMethod);
 					}
-				} else if (inheritedNonNullNess != null
+				} else if (inheritedNonNullNess == Boolean.FALSE // unannotated conflics only with inherited @Nullable
 							&& currentNonNullNess == null) 
 				{
-					// weak conflict (TODO reconsider this case)
 					if (currentArgument != null) {
 						scope.problemReporter().parameterLackingNullAnnotation(
 								currentArgument,