Merge branch 'pr-5008'

pmd · May 14, 2024 · 03f5f1a · 03f5f1a
2 parents f1701df + 4472521
commit 03f5f1a
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Showing 3 changed files with 44 additions and 4 deletions.
diff --git a/docs/pages/release_notes.md b/docs/pages/release_notes.md
@@ -34,6 +34,7 @@ Since this release, PMD will also expose any getter returning a collection of an
   * [#4973](https://github.com/pmd/pmd/pull/4973): \[java] Stop parsing Java for CPD
   * [#4980](https://github.com/pmd/pmd/issues/4980): \[java] Bad intersection, unrelated class types java.lang.Object\[] and java.lang.Number
   * [#4988](https://github.com/pmd/pmd/pull/4988): \[java] Fix impl of ASTVariableId::isResourceDeclaration / VariableId/@<!-- -->ResourceDeclaration
+  * [#5006](https://github.com/pmd/pmd/issues/5006): \[java] Bad intersection, unrelated class types Child and Parent<? extends Child>
 * java-bestpractices
   * [#4278](https://github.com/pmd/pmd/issues/4278): \[java] UnusedPrivateMethod FP with Junit 5 @MethodSource and default factory method name
   * [#4852](https://github.com/pmd/pmd/issues/4852): \[java] ReplaceVectorWithList false-positive (neither Vector nor List usage) 

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/types/Lub.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/types/Lub.java
@@ -340,10 +340,21 @@ static JTypeMirror glb(TypeSystem ts, Collection<? extends JTypeMirror> types) {
                     JTypeMirror componentGlb = glb(ts, setOf(((JArrayType) ci).getComponentType(),
                                                              ((JArrayType) primaryBound).getComponentType()));
                     primaryBound = ts.arrayType(componentGlb);
+
                 } else {
-                    throw new IllegalArgumentException(
-                        "Bad intersection, unrelated class types " + ci + " and " + primaryBound + " in " + types
-                    );
+                    // We have two primary bounds. This may happen during capture
+                    // of recursive F-bounded types. Here we do a last resort check
+                    // to see if one of the bounds is a subtype (unchecked) of the other.
+                    // In that case we pick this as primary bound as it is more specific.
+
+                    int cmp = compareRelatedness(ci.getErasure(), primaryBound.getErasure());
+                    if (cmp == 0) {
+                        throw new IllegalArgumentException(
+                            "Bad intersection, unrelated class types " + ci + " and " + primaryBound + " in " + types
+                        );
+                    } else if (cmp < 0) {
+                        primaryBound = ci;
+                    }
                 }
             } else {
                 bounds.add(ci);
@@ -366,6 +377,15 @@ static JTypeMirror glb(TypeSystem ts, Collection<? extends JTypeMirror> types) {
         return new JIntersectionType(ts, primaryBound, bounds);
     }
 
+    private static int compareRelatedness(JTypeMirror t, JTypeMirror s) {
+        if (TypeOps.isConvertiblePure(t, s.getErasure()).withoutWarnings()) {
+            return -1;
+        } else if (TypeOps.isConvertiblePure(s, t.getErasure()).withoutWarnings()) {
+            return 1;
+        }
+        return 0;
+    }
+
     private static void checkGlbComponent(Collection<? extends JTypeMirror> types, JTypeMirror ci) {
         if (ci.isPrimitive() || ci instanceof JWildcardType || ci instanceof JIntersectionType) {
             throw new IllegalArgumentException("Bad intersection type component: " + ci + " in " + types);

diff --git a/pmd-java/src/test/kotlin/net/sourceforge/pmd/lang/java/types/CaptureTest.kt b/pmd-java/src/test/kotlin/net/sourceforge/pmd/lang/java/types/CaptureTest.kt
@@ -9,11 +9,12 @@ import io.kotest.core.spec.style.FunSpec
 import io.kotest.matchers.shouldBe
 import net.sourceforge.pmd.lang.java.symbols.internal.asm.createUnresolvedAsmSymbol
 import net.sourceforge.pmd.lang.java.types.TypeConversion.*
+import net.sourceforge.pmd.lang.test.ast.IntelliMarker
 
 /**
  * @author Clément Fournier
  */
-class CaptureTest : FunSpec({
+class CaptureTest : IntelliMarker, FunSpec({
 
     with(TypeDslOf(testTypeSystem)) {
         with(gen) {
@@ -69,6 +70,24 @@ class CaptureTest : FunSpec({
                 }
             }
 
+            test("Capture of recursive types #5006") {
+                val acu = javaParser.parse("""
+                    class Parent<T extends Parent<T>> {} // Recursive type T
+
+                    class Child extends Parent<Child> {}
+
+                    class Box<T extends Parent<T>> {
+                      public void foo(Box<? extends Child> box) {} // <-- The bug is triggered by this line
+                    }
+                """.trimIndent())
+
+                val (_, child, box) = acu.declaredTypeSignatures()
+
+                val type = acu.methodDeclarations().first()!!.formalParameters.get(0).typeMirror
+
+                 capture(type) shouldBe box[captureMatcher(`?` extends child)]
+            }
+
         }
     }