check ref in foreach iterated value (IDEA-59874)

java/java-impl/src/com/intellij/codeInspection/inferNullity/NullityInferrer.java

@@ -466,6 +466,11 @@ public class NullityInferrer {
                     }
                   }
                 }
+              } else if (parent instanceof PsiForeachStatement) {
+                if (((PsiForeachStatement)parent).getIteratedValue() == expr) {
+                  registerNotNullAnnotation(parameter);
+                  return;
+                }
               }
 
               if (isNotNull(method)) {

java/java-tests/testData/codeInsight/nullityinferrer/afterParameterUsedInForeachIteratedValue.java

@@ -0,0 +1,9 @@
+import org.jetbrains.annotations.NotNull;
+
+import java.util.*;
+class Test {
+   void foo(@NotNull List requests){
+        for (Object request : requests) {
+        }
+    }
+}

java/java-tests/testData/codeInsight/nullityinferrer/beforeParameterUsedInForeachIteratedValue.java

@@ -0,0 +1,7 @@
+import java.util.*;
+class Test {
+   void foo(List requests){
+        for (Object request : requests) {
+        }
+    }
+}

java/java-tests/testSrc/com/intellij/codeInsight/NullityInferrerTest.java

@@ -50,6 +50,10 @@ public class NullityInferrerTest extends CodeInsightTestCase {
     doTest(false);
   }
 
+  public void testParameterUsedInForeachIteratedValue() throws Exception {
+    doTest(false);
+  }
+
   //-----------------------fields---------------------------------------------------
   public void testFieldsAssignment() throws Exception {
     doTest(false);