Compatibility inspection for dict unpacking in dict literals

python/src/com/jetbrains/python/validation/CompatibilityVisitor.java

@@ -172,28 +172,32 @@ public abstract class CompatibilityVisitor extends PyAnnotator {
     super.visitPyStarExpression(node);
 
     if (node.isAssignmentTarget()) {
-      boolean problem = false;
       for (LanguageLevel level : myVersionsToProcess) {
         if (level.isOlderThan(LanguageLevel.PYTHON30)) {
-          problem = true;
+          registerProblem(node, "Python versions < 3.0 do not support starred expressions as assignment targets");
           break;
         }
       }
-      if (problem) {
-        registerProblem(node, "Python versions < 3.0 do not support starred expressions as assignment targets");
-      }
     }
 
     if (node.isUnpacking()) {
-      boolean problem = false;
       for (LanguageLevel level : myVersionsToProcess) {
         if (level.isOlderThan(LanguageLevel.PYTHON35)) {
-          problem = true;
+          registerProblem(node, "Python versions < 3.5 do not support starred expressions in tuples, lists, and sets");
           break;
         }
       }
-      if (problem) {
-        registerProblem(node, "Python version < 3.5 do not support starred expressions in tuples, lists, and sets");
+    }
+  }
+
+  @Override
+  public void visitPyDoubleStarExpression(PyDoubleStarExpression node) {
+    super.visitPyDoubleStarExpression(node);
+
+    for (LanguageLevel level : myVersionsToProcess) {
+      if (level.isOlderThan(LanguageLevel.PYTHON35)) {
+        registerProblem(node, "Python versions < 3.5 do not support starred expressions in dicts");
+        break;
       }
     }
   }

python/testData/inspections/PyCompatibilityInspection/doubleStarUnpacking.py

@@ -0,0 +1,2 @@
+xs = {1: 2}
+ys = {<warning descr="Python versions < 3.5 do not support starred expressions in dicts">**xs</warning>, 3: 4}

python/testData/inspections/PyCompatibilityInspection/starExpression.py

@@ -1,2 +1,2 @@
-t = (1, <warning descr="Python version < 3.5 do not support starred expressions in tuples, lists, and sets">*(2, 3)</warning>)
+t = (1, <warning descr="Python versions < 3.5 do not support starred expressions in tuples, lists, and sets">*(2, 3)</warning>)
 a, <warning descr="Python versions < 3.0 do not support starred expressions as assignment targets">*b</warning>, c = t

python/testSrc/com/jetbrains/python/inspections/PyCompatibilityInspectionTest.java

@@ -159,6 +159,10 @@ public class PyCompatibilityInspectionTest extends PyTestCase {
     doTest(LanguageLevel.PYTHON35);
   }
 
+  public void testDoubleStarUnpacking() {
+    doTest(LanguageLevel.PYTHON35);
+  }
+
   private void doTest(@NotNull LanguageLevel level) {
     runWithLanguageLevel(level, new Runnable() {
       @Override