lambda: effectively final parameters: copy in final variable if needed - never make implicitly final

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/highlighting/EffectiveFinal.java

@@ -90,4 +90,28 @@ class Sample {
                 runnable.run();         // prints 111
                 runnable2.run();        // prints 444
         }
+}
+
+class ParameterIsEffectivelyFinal {
+  {
+    Comparable<String> c = o->{
+      new Runnable() {
+        @Override
+        public void run() {
+          System.out.println(o);
+        }
+      }.run();
+      return 0;
+    };
+    Comparable<String> c1 = o->{
+      o = "";
+      new Runnable() {
+        @Override
+        public void run() {
+          System.out.println(<error descr="Variable 'o' is accessed from within inner class. Needs to be declared final.">o</error>);
+        }
+      }.run();
+      return 0;
+    };
+  }
 }