do not complete after return based on info from containing method (IDEA-90729)

java/java-impl/src/com/intellij/codeInsight/completion/JavaCompletionData.java

@@ -371,6 +371,13 @@ public class JavaCompletionData extends JavaAwareCompletionData {
 
         return TailType.HUMBLE_SPACE_BEFORE_WORD;
       }
+      if (scope instanceof PsiLambdaExpression) {
+        final PsiType returnType = LambdaUtil.getFunctionalInterfaceReturnType(((PsiLambdaExpression)scope));
+        if (PsiType.VOID.equals(returnType)) {
+          return TailType.SEMICOLON;
+        }
+        return TailType.HUMBLE_SPACE_BEFORE_WORD;
+      }
       scope = scope.getParent();
     }
   }

java/java-psi-api/src/com/intellij/psi/LambdaUtil.java

@@ -31,6 +31,11 @@ import java.util.*;
 public class LambdaUtil {
   private static final Logger LOG = Logger.getInstance("#" + LambdaUtil.class.getName());
 
+  @Nullable
+  public static PsiType getFunctionalInterfaceReturnType(PsiLambdaExpression expr) {
+    return getFunctionalInterfaceReturnType(expr.getFunctionalInterfaceType());
+  }
+  
   @Nullable
   public static PsiType getFunctionalInterfaceReturnType(PsiType functionalInterfaceType) {
     final PsiClassType.ClassResolveResult resolveResult = PsiUtil.resolveGenericsClassInType(functionalInterfaceType);