TypeMayBeWeakenedInspection: not weaken when resource expr: IDEA-185994

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/WeakestTypeFinder.java

@@ -132,6 +132,13 @@ public class WeakestTypeFinder {
           return Collections.emptyList();
         }
       }
+      else if (referenceParent instanceof PsiResourceExpression) {
+        PsiClass closeable = facade.findClass(CommonClassNames.JAVA_LANG_AUTO_CLOSEABLE, scope);
+        if (closeable == null || variableOrMethodClass.equals(closeable)) {
+          return Collections.emptyList();
+        }
+        weakestTypeClasses.add(closeable);
+      }
       else if (referenceParent instanceof PsiAssignmentExpression) {
         final PsiAssignmentExpression assignmentExpression = (PsiAssignmentExpression)referenceParent;
         if (!findWeakestType(referenceElement, assignmentExpression, useRighthandTypeAsWeakestTypeInAssignments, weakestTypeClasses)) {

plugins/InspectionGadgets/test/com/siyeh/igtest/abstraction/weaken_type/TryWithResources.java

@@ -0,0 +1,23 @@
+import java.io.Closeable;
+
+class DummyClass {
+
+  public void doSomething() {
+  }
+}
+
+class CloseableDummyClass extends DummyClass implements Closeable {
+
+  @Override
+  public void close() {
+  }
+}
+
+class CallerClass {
+
+  public void call(CloseableDummyClass closeableDummyClass) {
+    try (closeableDummyClass) {
+      closeableDummyClass.doSomething();
+    }
+  }
+}

plugins/InspectionGadgets/testsrc/com/siyeh/ig/abstraction/TypeMayBeWeakenedInspectionTest.java

@@ -10,6 +10,7 @@ public class TypeMayBeWeakenedInspectionTest extends LightInspectionTestCase {
   public void testNumberAdderDemo() { doTest(); }
   public void testAutoClosableTest() { doTest(); }
   public void testLambda() { doTest(); }
+  public void testTryWithResources() { doTest(); }
 
   @Override
   protected String[] getEnvironmentClasses() {