diff --git a/compiler/android-tests/tests/org/jetbrains/jet/compiler/android/SpecialFiles.java b/compiler/android-tests/tests/org/jetbrains/jet/compiler/android/SpecialFiles.java
index 38785b4056b..5f91659d132 100644
--- a/compiler/android-tests/tests/org/jetbrains/jet/compiler/android/SpecialFiles.java
+++ b/compiler/android-tests/tests/org/jetbrains/jet/compiler/android/SpecialFiles.java
@@ -64,13 +64,13 @@ public class SpecialFiles {
     private static void fillFilesCompiledWithoutStdLib() {
         filesCompiledWithoutStdLib.add("kt1980.kt");
         filesCompiledWithoutStdLib.add("kt1953_class.kt"); // Exception in code
-        filesCompiledWithoutStdLib.add("basicmethodSuperClass.jet"); // Exception in code
-        filesCompiledWithoutStdLib.add("kt503.jet"); // OVERLOAD_RESOLUTION_AMBIGUITY
-        filesCompiledWithoutStdLib.add("kt504.jet"); // OVERLOAD_RESOLUTION_AMBIGUITY
-        filesCompiledWithoutStdLib.add("kt772.jet"); // OVERLOAD_RESOLUTION_AMBIGUITY
-        filesCompiledWithoutStdLib.add("kt773.jet"); // OVERLOAD_RESOLUTION_AMBIGUITY
-        filesCompiledWithoutStdLib.add("kt796_797.jet"); // OVERLOAD_RESOLUTION_AMBIGUITY
-        filesCompiledWithoutStdLib.add("kt950.jet"); // OVERLOAD_RESOLUTION_AMBIGUITY
+        filesCompiledWithoutStdLib.add("basicmethodSuperClass.kt"); // Exception in code
+        filesCompiledWithoutStdLib.add("kt503.kt"); // OVERLOAD_RESOLUTION_AMBIGUITY
+        filesCompiledWithoutStdLib.add("kt504.kt"); // OVERLOAD_RESOLUTION_AMBIGUITY
+        filesCompiledWithoutStdLib.add("kt772.kt"); // OVERLOAD_RESOLUTION_AMBIGUITY
+        filesCompiledWithoutStdLib.add("kt773.kt"); // OVERLOAD_RESOLUTION_AMBIGUITY
+        filesCompiledWithoutStdLib.add("kt796_797.kt"); // OVERLOAD_RESOLUTION_AMBIGUITY
+        filesCompiledWithoutStdLib.add("kt950.kt"); // OVERLOAD_RESOLUTION_AMBIGUITY
         filesCompiledWithoutStdLib.add("kt2395.kt"); // With MOCK_JDK
     }
 
@@ -84,26 +84,25 @@ public class SpecialFiles {
         excludedFiles.add("simpleJavaEnumWithStaticImport.kt"); // Must compile Java files before
         excludedFiles.add("removeInIterator.kt"); // Must compile Java files before
         excludedFiles.add("kt3238.kt"); // Reflection
-        excludedFiles.add("namespaceQualifiedMethod.jet"); // Cannot change package name
+        excludedFiles.add("namespaceQualifiedMethod.kt"); // Cannot change package name
         excludedFiles.add("kt1482_2279.kt"); // Cannot change package name
         excludedFiles.add("kt1482.kt"); // Cannot change package name
-        excludedFiles.add("importFromClassObject.jet"); // Cannot find usages in Codegen tests
-        excludedFiles.add("withtypeparams.jet"); // Cannot find usages in Codegen tests
+        excludedFiles.add("importFromClassObject.kt"); // Cannot find usages in Codegen tests
+        excludedFiles.add("withtypeparams.kt"); // Cannot find usages in Codegen tests
         excludedFiles.add("kt1113.kt"); // Commented
-        excludedFiles.add("kt326.jet"); // Commented
+        excludedFiles.add("kt326.kt"); // Commented
         excludedFiles.add("kt1213.kt"); // Commented
-        excludedFiles.add("kt882.jet"); // Commented
-        excludedFiles.add("kt789.jet"); // Commented
+        excludedFiles.add("kt882.kt"); // Commented
+        excludedFiles.add("kt789.kt"); // Commented
         excludedFiles.add("enum.kt"); // Commented
         excludedFiles.add("withclosure.kt"); // Commented
-        excludedFiles.add("isTypeParameter.jet"); // Commented
-        excludedFiles.add("nullability.jet"); // Commented
-        excludedFiles.add("genericFunction.jet"); // Commented
-        excludedFiles.add("forwardTypeParameter.jet"); // Commented
-        excludedFiles.add("kt259.jet"); // Commented
-        excludedFiles.add("classObjectMethod.jet"); // Commented
+        excludedFiles.add("isTypeParameter.kt"); // Commented
+        excludedFiles.add("nullability.kt"); // Commented
+        excludedFiles.add("genericFunction.kt"); // Commented
+        excludedFiles.add("forwardTypeParameter.kt"); // Commented
+        excludedFiles.add("classObjectMethod.kt"); // Commented
 
-        excludedFiles.add("inRangeConditionsInWhen.jet"); // Commented
+        excludedFiles.add("inRangeConditionsInWhen.kt"); // Commented
         excludedFiles.add("kt1592.kt"); // Codegen don't execute blackBoxFile() on it
 
         excludedFiles.add("box.kt");      // MultiFileTest not supported yet
@@ -112,9 +111,10 @@ public class SpecialFiles {
         excludedFiles.add("kt1528_1.kt"); // MultiFileTest not supported yet
         excludedFiles.add("thisPackage.kt"); // MultiFileTest not supported yet
 
-        excludedFiles.add("kt684.jet"); // StackOverflow with StringBuilder (escape())
+        excludedFiles.add("kt684.kt"); // StackOverflow with StringBuilder (escape())
 
-        excludedFiles.add("kt344.jet"); // Bug KT-2251
+        excludedFiles.add("kt344.kt"); // Bug KT-2251
+        excludedFiles.add("kt529.kt");  // Bug
 
         excludedFiles.add("noClassObjectForJavaClass.kt");
 
diff --git a/compiler/testData/codegen/PSVM.jet b/compiler/testData/codegen/PSVM.kt
similarity index 100%
rename from compiler/testData/codegen/PSVM.jet
rename to compiler/testData/codegen/PSVM.kt
diff --git a/compiler/testData/codegen/assign.jet b/compiler/testData/codegen/assign.kt
similarity index 100%
rename from compiler/testData/codegen/assign.jet
rename to compiler/testData/codegen/assign.kt
diff --git a/compiler/testData/codegen/bottles.jet b/compiler/testData/codegen/bottles.kt
similarity index 100%
rename from compiler/testData/codegen/bottles.jet
rename to compiler/testData/codegen/bottles.kt
diff --git a/compiler/testData/codegen/bottles2.jet b/compiler/testData/codegen/bottles2.kt
similarity index 100%
rename from compiler/testData/codegen/bottles2.jet
rename to compiler/testData/codegen/bottles2.kt
diff --git a/compiler/testData/codegen/bridge.jet b/compiler/testData/codegen/bridge.kt
similarity index 100%
rename from compiler/testData/codegen/bridge.jet
rename to compiler/testData/codegen/bridge.kt
diff --git a/compiler/testData/codegen/checkCast.jet b/compiler/testData/codegen/checkCast.kt
similarity index 100%
rename from compiler/testData/codegen/checkCast.jet
rename to compiler/testData/codegen/checkCast.kt
diff --git a/compiler/testData/codegen/classes/classObject.jet b/compiler/testData/codegen/classes/classObject.kt
similarity index 100%
rename from compiler/testData/codegen/classes/classObject.jet
rename to compiler/testData/codegen/classes/classObject.kt
diff --git a/compiler/testData/codegen/classes/classObjectInTrait.jet b/compiler/testData/codegen/classes/classObjectInTrait.kt
similarity index 100%
rename from compiler/testData/codegen/classes/classObjectInTrait.jet
rename to compiler/testData/codegen/classes/classObjectInTrait.kt
diff --git a/compiler/testData/codegen/classes/classObjectInterface.jet b/compiler/testData/codegen/classes/classObjectInterface.kt
similarity index 100%
rename from compiler/testData/codegen/classes/classObjectInterface.jet
rename to compiler/testData/codegen/classes/classObjectInterface.kt
diff --git a/compiler/testData/codegen/classes/classObjectMethod.jet b/compiler/testData/codegen/classes/classObjectMethod.kt
similarity index 100%
rename from compiler/testData/codegen/classes/classObjectMethod.jet
rename to compiler/testData/codegen/classes/classObjectMethod.kt
diff --git a/compiler/testData/codegen/classes/closureWithParameter.jet b/compiler/testData/codegen/classes/closureWithParameter.kt
similarity index 100%
rename from compiler/testData/codegen/classes/closureWithParameter.jet
rename to compiler/testData/codegen/classes/closureWithParameter.kt
diff --git a/compiler/testData/codegen/classes/closureWithParameterAndBoxing.jet b/compiler/testData/codegen/classes/closureWithParameterAndBoxing.kt
similarity index 100%
rename from compiler/testData/codegen/classes/closureWithParameterAndBoxing.jet
rename to compiler/testData/codegen/classes/closureWithParameterAndBoxing.kt
diff --git a/compiler/testData/codegen/classes/diamondInheritance.jet b/compiler/testData/codegen/classes/diamondInheritance.kt
similarity index 100%
rename from compiler/testData/codegen/classes/diamondInheritance.jet
rename to compiler/testData/codegen/classes/diamondInheritance.kt
diff --git a/compiler/testData/codegen/classes/doubleEnclosedLocalVariable.jet b/compiler/testData/codegen/classes/doubleEnclosedLocalVariable.kt
similarity index 100%
rename from compiler/testData/codegen/classes/doubleEnclosedLocalVariable.jet
rename to compiler/testData/codegen/classes/doubleEnclosedLocalVariable.kt
diff --git a/compiler/testData/codegen/classes/enclosingLocalVariable.jet b/compiler/testData/codegen/classes/enclosingLocalVariable.kt
similarity index 100%
rename from compiler/testData/codegen/classes/enclosingLocalVariable.jet
rename to compiler/testData/codegen/classes/enclosingLocalVariable.kt
diff --git a/compiler/testData/codegen/classes/enclosingThis.jet b/compiler/testData/codegen/classes/enclosingThis.kt
similarity index 100%
rename from compiler/testData/codegen/classes/enclosingThis.jet
rename to compiler/testData/codegen/classes/enclosingThis.kt
diff --git a/compiler/testData/codegen/classes/exceptionConstructor.jet b/compiler/testData/codegen/classes/exceptionConstructor.kt
similarity index 100%
rename from compiler/testData/codegen/classes/exceptionConstructor.jet
rename to compiler/testData/codegen/classes/exceptionConstructor.kt
diff --git a/compiler/testData/codegen/classes/extensionClosure.jet b/compiler/testData/codegen/classes/extensionClosure.kt
similarity index 100%
rename from compiler/testData/codegen/classes/extensionClosure.jet
rename to compiler/testData/codegen/classes/extensionClosure.kt
diff --git a/compiler/testData/codegen/classes/funDelegation.jet b/compiler/testData/codegen/classes/funDelegation.kt
similarity index 100%
rename from compiler/testData/codegen/classes/funDelegation.jet
rename to compiler/testData/codegen/classes/funDelegation.kt
diff --git a/compiler/testData/codegen/classes/inheritance.jet b/compiler/testData/codegen/classes/inheritance.kt
similarity index 100%
rename from compiler/testData/codegen/classes/inheritance.jet
rename to compiler/testData/codegen/classes/inheritance.kt
diff --git a/compiler/testData/codegen/classes/inheritedInnerClass.jet b/compiler/testData/codegen/classes/inheritedInnerClass.kt
similarity index 100%
rename from compiler/testData/codegen/classes/inheritedInnerClass.jet
rename to compiler/testData/codegen/classes/inheritedInnerClass.kt
diff --git a/compiler/testData/codegen/classes/inheritedMethod.jet b/compiler/testData/codegen/classes/inheritedMethod.kt
similarity index 100%
rename from compiler/testData/codegen/classes/inheritedMethod.jet
rename to compiler/testData/codegen/classes/inheritedMethod.kt
diff --git a/compiler/testData/codegen/classes/inheritingFromArrayList.jet b/compiler/testData/codegen/classes/inheritingFromArrayList.kt
similarity index 100%
rename from compiler/testData/codegen/classes/inheritingFromArrayList.jet
rename to compiler/testData/codegen/classes/inheritingFromArrayList.kt
diff --git a/compiler/testData/codegen/classes/initializerBlock.jet b/compiler/testData/codegen/classes/initializerBlock.kt
similarity index 100%
rename from compiler/testData/codegen/classes/initializerBlock.jet
rename to compiler/testData/codegen/classes/initializerBlock.kt
diff --git a/compiler/testData/codegen/classes/initializerBlockDImpl.jet b/compiler/testData/codegen/classes/initializerBlockDImpl.kt
similarity index 100%
rename from compiler/testData/codegen/classes/initializerBlockDImpl.jet
rename to compiler/testData/codegen/classes/initializerBlockDImpl.kt
diff --git a/compiler/testData/codegen/classes/innerClass.jet b/compiler/testData/codegen/classes/innerClass.kt
similarity index 100%
rename from compiler/testData/codegen/classes/innerClass.jet
rename to compiler/testData/codegen/classes/innerClass.kt
diff --git a/compiler/testData/codegen/classes/newInstanceDefaultConstructor.jet b/compiler/testData/codegen/classes/newInstanceDefaultConstructor.kt
similarity index 100%
rename from compiler/testData/codegen/classes/newInstanceDefaultConstructor.jet
rename to compiler/testData/codegen/classes/newInstanceDefaultConstructor.kt
diff --git a/compiler/testData/codegen/classes/nonnullarray.jet b/compiler/testData/codegen/classes/nonnullarray.kt
similarity index 100%
rename from compiler/testData/codegen/classes/nonnullarray.jet
rename to compiler/testData/codegen/classes/nonnullarray.kt
diff --git a/compiler/testData/codegen/classes/outerThis.jet b/compiler/testData/codegen/classes/outerThis.kt
similarity index 100%
rename from compiler/testData/codegen/classes/outerThis.jet
rename to compiler/testData/codegen/classes/outerThis.kt
diff --git a/compiler/testData/codegen/classes/overloadBinaryOperator.jet b/compiler/testData/codegen/classes/overloadBinaryOperator.kt
similarity index 100%
rename from compiler/testData/codegen/classes/overloadBinaryOperator.jet
rename to compiler/testData/codegen/classes/overloadBinaryOperator.kt
diff --git a/compiler/testData/codegen/classes/overloadPlusAssign.jet b/compiler/testData/codegen/classes/overloadPlusAssign.kt
similarity index 100%
rename from compiler/testData/codegen/classes/overloadPlusAssign.jet
rename to compiler/testData/codegen/classes/overloadPlusAssign.kt
diff --git a/compiler/testData/codegen/classes/overloadPlusToPlusAssign.jet b/compiler/testData/codegen/classes/overloadPlusAssignReturn.kt
similarity index 100%
rename from compiler/testData/codegen/classes/overloadPlusToPlusAssign.jet
rename to compiler/testData/codegen/classes/overloadPlusAssignReturn.kt
diff --git a/compiler/testData/codegen/classes/overloadPlusAssignReturn.jet b/compiler/testData/codegen/classes/overloadPlusToPlusAssign.kt
similarity index 100%
rename from compiler/testData/codegen/classes/overloadPlusAssignReturn.jet
rename to compiler/testData/codegen/classes/overloadPlusToPlusAssign.kt
diff --git a/compiler/testData/codegen/classes/overloadUnaryOperator.jet b/compiler/testData/codegen/classes/overloadUnaryOperator.kt
similarity index 100%
rename from compiler/testData/codegen/classes/overloadUnaryOperator.jet
rename to compiler/testData/codegen/classes/overloadUnaryOperator.kt
diff --git a/compiler/testData/codegen/classes/propertyDelegation.jet b/compiler/testData/codegen/classes/propertyDelegation.kt
similarity index 100%
rename from compiler/testData/codegen/classes/propertyDelegation.jet
rename to compiler/testData/codegen/classes/propertyDelegation.kt
diff --git a/compiler/testData/codegen/classes/propertyInInitializer.jet b/compiler/testData/codegen/classes/propertyInInitializer.kt
similarity index 100%
rename from compiler/testData/codegen/classes/propertyInInitializer.jet
rename to compiler/testData/codegen/classes/propertyInInitializer.kt
diff --git a/compiler/testData/codegen/classes/resolveOrder.jet b/compiler/testData/codegen/classes/resolveOrder.kt
similarity index 100%
rename from compiler/testData/codegen/classes/resolveOrder.jet
rename to compiler/testData/codegen/classes/resolveOrder.kt
diff --git a/compiler/testData/codegen/classes/rightHandOverride.jet b/compiler/testData/codegen/classes/rightHandOverride.kt
similarity index 100%
rename from compiler/testData/codegen/classes/rightHandOverride.jet
rename to compiler/testData/codegen/classes/rightHandOverride.kt
diff --git a/compiler/testData/codegen/classes/simpleBox.jet b/compiler/testData/codegen/classes/simpleBox.kt
similarity index 100%
rename from compiler/testData/codegen/classes/simpleBox.jet
rename to compiler/testData/codegen/classes/simpleBox.kt
diff --git a/compiler/testData/codegen/classes/simpleClass.jet b/compiler/testData/codegen/classes/simpleClass.kt
similarity index 100%
rename from compiler/testData/codegen/classes/simpleClass.jet
rename to compiler/testData/codegen/classes/simpleClass.kt
diff --git a/compiler/testData/codegen/classes/simplestClosure.jet b/compiler/testData/codegen/classes/simplestClosure.kt
similarity index 100%
rename from compiler/testData/codegen/classes/simplestClosure.jet
rename to compiler/testData/codegen/classes/simplestClosure.kt
diff --git a/compiler/testData/codegen/classes/simplestClosureAndBoxing.jet b/compiler/testData/codegen/classes/simplestClosureAndBoxing.kt
similarity index 100%
rename from compiler/testData/codegen/classes/simplestClosureAndBoxing.jet
rename to compiler/testData/codegen/classes/simplestClosureAndBoxing.kt
diff --git a/compiler/testData/codegen/controlStructures/break.jet b/compiler/testData/codegen/controlStructures/break.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/break.jet
rename to compiler/testData/codegen/controlStructures/break.kt
diff --git a/compiler/testData/codegen/controlStructures/continue.jet b/compiler/testData/codegen/controlStructures/continue.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/continue.jet
rename to compiler/testData/codegen/controlStructures/continue.kt
diff --git a/compiler/testData/codegen/controlStructures/doWhile.jet b/compiler/testData/codegen/controlStructures/doWhile.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/doWhile.jet
rename to compiler/testData/codegen/controlStructures/doWhile.kt
diff --git a/compiler/testData/codegen/controlStructures/for.jet b/compiler/testData/codegen/controlStructures/for.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/for.jet
rename to compiler/testData/codegen/controlStructures/for.kt
diff --git a/compiler/testData/codegen/controlStructures/forInArray.jet b/compiler/testData/codegen/controlStructures/forInArray.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/forInArray.jet
rename to compiler/testData/codegen/controlStructures/forInArray.kt
diff --git a/compiler/testData/codegen/controlStructures/forIntArray.jet b/compiler/testData/codegen/controlStructures/forIntArray.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/forIntArray.jet
rename to compiler/testData/codegen/controlStructures/forIntArray.kt
diff --git a/compiler/testData/codegen/controlStructures/forIntRange.jet b/compiler/testData/codegen/controlStructures/forIntRange.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/forIntRange.jet
rename to compiler/testData/codegen/controlStructures/forIntRange.kt
diff --git a/compiler/testData/codegen/controlStructures/forNullableIntArray.jet b/compiler/testData/codegen/controlStructures/forNullableIntArray.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/forNullableIntArray.jet
rename to compiler/testData/codegen/controlStructures/forNullableIntArray.kt
diff --git a/compiler/testData/codegen/controlStructures/forPrimitiveIntArray.jet b/compiler/testData/codegen/controlStructures/forPrimitiveIntArray.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/forPrimitiveIntArray.jet
rename to compiler/testData/codegen/controlStructures/forPrimitiveIntArray.kt
diff --git a/compiler/testData/codegen/controlStructures/forUserType.jet b/compiler/testData/codegen/controlStructures/forUserType.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/forUserType.jet
rename to compiler/testData/codegen/controlStructures/forUserType.kt
diff --git a/compiler/testData/codegen/controlStructures/if.jet b/compiler/testData/codegen/controlStructures/if.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/if.jet
rename to compiler/testData/codegen/controlStructures/if.kt
diff --git a/compiler/testData/codegen/controlStructures/ifBlock.jet b/compiler/testData/codegen/controlStructures/ifBlock.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/ifBlock.jet
rename to compiler/testData/codegen/controlStructures/ifBlock.kt
diff --git a/compiler/testData/codegen/controlStructures/ifInWhile.jet b/compiler/testData/codegen/controlStructures/ifInWhile.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/ifInWhile.jet
rename to compiler/testData/codegen/controlStructures/ifInWhile.kt
diff --git a/compiler/testData/codegen/controlStructures/ifNoElse.jet b/compiler/testData/codegen/controlStructures/ifNoElse.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/ifNoElse.jet
rename to compiler/testData/codegen/controlStructures/ifNoElse.kt
diff --git a/compiler/testData/codegen/controlStructures/inRangeConditionsInWhen.jet b/compiler/testData/codegen/controlStructures/inRangeConditionsInWhen.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/inRangeConditionsInWhen.jet
rename to compiler/testData/codegen/controlStructures/inRangeConditionsInWhen.kt
diff --git a/compiler/testData/codegen/controlStructures/longRange.jet b/compiler/testData/codegen/controlStructures/longRange.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/longRange.jet
rename to compiler/testData/codegen/controlStructures/longRange.kt
diff --git a/compiler/testData/codegen/controlStructures/quicksort.jet b/compiler/testData/codegen/controlStructures/quicksort.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/quicksort.jet
rename to compiler/testData/codegen/controlStructures/quicksort.kt
diff --git a/compiler/testData/codegen/controlStructures/singleBranchIf.jet b/compiler/testData/codegen/controlStructures/singleBranchIf.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/singleBranchIf.jet
rename to compiler/testData/codegen/controlStructures/singleBranchIf.kt
diff --git a/compiler/testData/codegen/controlStructures/sync.jet b/compiler/testData/codegen/controlStructures/sync.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/sync.jet
rename to compiler/testData/codegen/controlStructures/sync.kt
diff --git a/compiler/testData/codegen/controlStructures/tryCatch.jet b/compiler/testData/codegen/controlStructures/tryCatch.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/tryCatch.jet
rename to compiler/testData/codegen/controlStructures/tryCatch.kt
diff --git a/compiler/testData/codegen/controlStructures/tryFinally.jet b/compiler/testData/codegen/controlStructures/tryFinally.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/tryFinally.jet
rename to compiler/testData/codegen/controlStructures/tryFinally.kt
diff --git a/compiler/testData/codegen/controlStructures/while.jet b/compiler/testData/codegen/controlStructures/while.kt
similarity index 100%
rename from compiler/testData/codegen/controlStructures/while.jet
rename to compiler/testData/codegen/controlStructures/while.kt
diff --git a/compiler/testData/codegen/extensionFunctions/generic.jet b/compiler/testData/codegen/extensionFunctions/generic.kt
similarity index 100%
rename from compiler/testData/codegen/extensionFunctions/generic.jet
rename to compiler/testData/codegen/extensionFunctions/generic.kt
diff --git a/compiler/testData/codegen/extensionFunctions/simple.jet b/compiler/testData/codegen/extensionFunctions/simple.kt
similarity index 100%
rename from compiler/testData/codegen/extensionFunctions/simple.jet
rename to compiler/testData/codegen/extensionFunctions/simple.kt
diff --git a/compiler/testData/codegen/extensionFunctions/virtual.jet b/compiler/testData/codegen/extensionFunctions/virtual.kt
similarity index 100%
rename from compiler/testData/codegen/extensionFunctions/virtual.jet
rename to compiler/testData/codegen/extensionFunctions/virtual.kt
diff --git a/compiler/testData/codegen/extensionFunctions/whenFail.jet b/compiler/testData/codegen/extensionFunctions/whenFail.kt
similarity index 100%
rename from compiler/testData/codegen/extensionFunctions/whenFail.jet
rename to compiler/testData/codegen/extensionFunctions/whenFail.kt
diff --git a/compiler/testData/codegen/functionCall.jet b/compiler/testData/codegen/functionCall.kt
similarity index 100%
rename from compiler/testData/codegen/functionCall.jet
rename to compiler/testData/codegen/functionCall.kt
diff --git a/compiler/testData/codegen/functions/defaultargs.jet b/compiler/testData/codegen/functions/defaultargs.kt
similarity index 100%
rename from compiler/testData/codegen/functions/defaultargs.jet
rename to compiler/testData/codegen/functions/defaultargs.kt
diff --git a/compiler/testData/codegen/functions/defaultargs1.jet b/compiler/testData/codegen/functions/defaultargs1.kt
similarity index 100%
rename from compiler/testData/codegen/functions/defaultargs1.jet
rename to compiler/testData/codegen/functions/defaultargs1.kt
diff --git a/compiler/testData/codegen/functions/defaultargs2.jet b/compiler/testData/codegen/functions/defaultargs2.kt
similarity index 100%
rename from compiler/testData/codegen/functions/defaultargs2.jet
rename to compiler/testData/codegen/functions/defaultargs2.kt
diff --git a/compiler/testData/codegen/functions/defaultargs3.jet b/compiler/testData/codegen/functions/defaultargs3.kt
similarity index 100%
rename from compiler/testData/codegen/functions/defaultargs3.jet
rename to compiler/testData/codegen/functions/defaultargs3.kt
diff --git a/compiler/testData/codegen/functions/defaultargs4.jet b/compiler/testData/codegen/functions/defaultargs4.kt
similarity index 100%
rename from compiler/testData/codegen/functions/defaultargs4.jet
rename to compiler/testData/codegen/functions/defaultargs4.kt
diff --git a/compiler/testData/codegen/functions/defaultargs5.jet b/compiler/testData/codegen/functions/defaultargs5.kt
similarity index 100%
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rename from compiler/testData/codegen/regressions/kt882.jet
rename to compiler/testData/codegen/regressions/kt882.kt
diff --git a/compiler/testData/codegen/regressions/kt887.jet b/compiler/testData/codegen/regressions/kt887.kt
similarity index 100%
rename from compiler/testData/codegen/regressions/kt887.jet
rename to compiler/testData/codegen/regressions/kt887.kt
diff --git a/compiler/testData/codegen/regressions/kt889.jet b/compiler/testData/codegen/regressions/kt889.kt
similarity index 100%
rename from compiler/testData/codegen/regressions/kt889.jet
rename to compiler/testData/codegen/regressions/kt889.kt
diff --git a/compiler/testData/codegen/regressions/kt894.jet b/compiler/testData/codegen/regressions/kt894.kt
similarity index 100%
rename from compiler/testData/codegen/regressions/kt894.jet
rename to compiler/testData/codegen/regressions/kt894.kt
diff --git a/compiler/testData/codegen/regressions/kt903.jet b/compiler/testData/codegen/regressions/kt903.kt
similarity index 100%
rename from compiler/testData/codegen/regressions/kt903.jet
rename to compiler/testData/codegen/regressions/kt903.kt
diff --git a/compiler/testData/codegen/regressions/kt945.jet b/compiler/testData/codegen/regressions/kt945.kt
similarity index 100%
rename from compiler/testData/codegen/regressions/kt945.jet
rename to compiler/testData/codegen/regressions/kt945.kt
diff --git a/compiler/testData/codegen/regressions/kt950.jet b/compiler/testData/codegen/regressions/kt950.kt
similarity index 100%
rename from compiler/testData/codegen/regressions/kt950.jet
rename to compiler/testData/codegen/regressions/kt950.kt
diff --git a/compiler/testData/codegen/regressions/kt958.jet b/compiler/testData/codegen/regressions/kt958.kt
similarity index 100%
rename from compiler/testData/codegen/regressions/kt958.jet
rename to compiler/testData/codegen/regressions/kt958.kt
diff --git a/compiler/testData/codegen/super/basicmethodSuperClass.jet b/compiler/testData/codegen/super/basicmethodSuperClass.kt
similarity index 100%
rename from compiler/testData/codegen/super/basicmethodSuperClass.jet
rename to compiler/testData/codegen/super/basicmethodSuperClass.kt
diff --git a/compiler/testData/codegen/super/basicmethodSuperTrait.jet b/compiler/testData/codegen/super/basicmethodSuperTrait.kt
similarity index 100%
rename from compiler/testData/codegen/super/basicmethodSuperTrait.jet
rename to compiler/testData/codegen/super/basicmethodSuperTrait.kt
diff --git a/compiler/testData/codegen/super/basicproperty.jet b/compiler/testData/codegen/super/basicproperty.kt
similarity index 100%
rename from compiler/testData/codegen/super/basicproperty.jet
rename to compiler/testData/codegen/super/basicproperty.kt
diff --git a/compiler/testData/codegen/super/enclosedFun.jet b/compiler/testData/codegen/super/enclosedFun.kt
similarity index 100%
rename from compiler/testData/codegen/super/enclosedFun.jet
rename to compiler/testData/codegen/super/enclosedFun.kt
diff --git a/compiler/testData/codegen/super/enclosedVar.jet b/compiler/testData/codegen/super/enclosedVar.kt
similarity index 100%
rename from compiler/testData/codegen/super/enclosedVar.jet
rename to compiler/testData/codegen/super/enclosedVar.kt
diff --git a/compiler/testData/codegen/super/traitproperty.jet b/compiler/testData/codegen/super/traitproperty.kt
similarity index 100%
rename from compiler/testData/codegen/super/traitproperty.jet
rename to compiler/testData/codegen/super/traitproperty.kt
diff --git a/compiler/testData/codegen/systemOut.jet b/compiler/testData/codegen/systemOut.kt
similarity index 100%
rename from compiler/testData/codegen/systemOut.jet
rename to compiler/testData/codegen/systemOut.kt
diff --git a/compiler/testData/codegen/traits/finalMethod.jet b/compiler/testData/codegen/traits/finalMethod.kt
similarity index 100%
rename from compiler/testData/codegen/traits/finalMethod.jet
rename to compiler/testData/codegen/traits/finalMethod.kt
diff --git a/compiler/testData/codegen/traits/inheritedFun.jet b/compiler/testData/codegen/traits/inheritedFun.kt
similarity index 100%
rename from compiler/testData/codegen/traits/inheritedFun.jet
rename to compiler/testData/codegen/traits/inheritedFun.kt
diff --git a/compiler/testData/codegen/traits/inheritedVar.jet b/compiler/testData/codegen/traits/inheritedVar.kt
similarity index 100%
rename from compiler/testData/codegen/traits/inheritedVar.jet
rename to compiler/testData/codegen/traits/inheritedVar.kt
diff --git a/compiler/testData/codegen/traits/multiple.jet b/compiler/testData/codegen/traits/multiple.kt
similarity index 100%
rename from compiler/testData/codegen/traits/multiple.jet
rename to compiler/testData/codegen/traits/multiple.kt
diff --git a/compiler/testData/codegen/traits/simple.jet b/compiler/testData/codegen/traits/simple.kt
similarity index 100%
rename from compiler/testData/codegen/traits/simple.jet
rename to compiler/testData/codegen/traits/simple.kt
diff --git a/compiler/testData/codegen/traits/stdlib.jet b/compiler/testData/codegen/traits/stdlib.kt
similarity index 100%
rename from compiler/testData/codegen/traits/stdlib.jet
rename to compiler/testData/codegen/traits/stdlib.kt
diff --git a/compiler/testData/codegen/traits/withRequired.jet b/compiler/testData/codegen/traits/withRequired.kt
similarity index 100%
rename from compiler/testData/codegen/traits/withRequired.jet
rename to compiler/testData/codegen/traits/withRequired.kt
diff --git a/compiler/testData/codegen/typeCastException.jet b/compiler/testData/codegen/typeCastException.kt
similarity index 100%
rename from compiler/testData/codegen/typeCastException.jet
rename to compiler/testData/codegen/typeCastException.kt
diff --git a/compiler/testData/codegen/typeInfo/asInLoop.jet b/compiler/testData/codegen/typeInfo/asInLoop.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/asInLoop.jet
rename to compiler/testData/codegen/typeInfo/asInLoop.kt
diff --git a/compiler/testData/codegen/typeInfo/asSafeWithGenerics.jet b/compiler/testData/codegen/typeInfo/asSafeWithGenerics.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/asSafeWithGenerics.jet
rename to compiler/testData/codegen/typeInfo/asSafeWithGenerics.kt
diff --git a/compiler/testData/codegen/typeInfo/classObjectInTypeInfo.jet b/compiler/testData/codegen/typeInfo/classObjectInTypeInfo.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/classObjectInTypeInfo.jet
rename to compiler/testData/codegen/typeInfo/classObjectInTypeInfo.kt
diff --git a/compiler/testData/codegen/typeInfo/forwardTypeParameter.jet b/compiler/testData/codegen/typeInfo/forwardTypeParameter.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/forwardTypeParameter.jet
rename to compiler/testData/codegen/typeInfo/forwardTypeParameter.kt
diff --git a/compiler/testData/codegen/typeInfo/genericFunction.jet b/compiler/testData/codegen/typeInfo/genericFunction.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/genericFunction.jet
rename to compiler/testData/codegen/typeInfo/genericFunction.kt
diff --git a/compiler/testData/codegen/typeInfo/getTypeInfo.jet b/compiler/testData/codegen/typeInfo/getTypeInfo.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/getTypeInfo.jet
rename to compiler/testData/codegen/typeInfo/getTypeInfo.kt
diff --git a/compiler/testData/codegen/typeInfo/inheritance.jet b/compiler/testData/codegen/typeInfo/inheritance.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/inheritance.jet
rename to compiler/testData/codegen/typeInfo/inheritance.kt
diff --git a/compiler/testData/codegen/typeInfo/inner.jet b/compiler/testData/codegen/typeInfo/inner.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/inner.jet
rename to compiler/testData/codegen/typeInfo/inner.kt
diff --git a/compiler/testData/codegen/typeInfo/isTypeParameter.jet b/compiler/testData/codegen/typeInfo/isTypeParameter.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/isTypeParameter.jet
rename to compiler/testData/codegen/typeInfo/isTypeParameter.kt
diff --git a/compiler/testData/codegen/typeInfo/isWithGenericParameters.jet b/compiler/testData/codegen/typeInfo/isWithGenericParameters.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/isWithGenericParameters.jet
rename to compiler/testData/codegen/typeInfo/isWithGenericParameters.kt
diff --git a/compiler/testData/codegen/typeInfo/isWithGenerics.jet b/compiler/testData/codegen/typeInfo/isWithGenerics.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/isWithGenerics.jet
rename to compiler/testData/codegen/typeInfo/isWithGenerics.kt
diff --git a/compiler/testData/codegen/typeInfo/nullability.jet b/compiler/testData/codegen/typeInfo/nullability.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/nullability.jet
rename to compiler/testData/codegen/typeInfo/nullability.kt
diff --git a/compiler/testData/codegen/typeInfo/oneArgTypeinfo.jet b/compiler/testData/codegen/typeInfo/oneArgTypeinfo.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/oneArgTypeinfo.jet
rename to compiler/testData/codegen/typeInfo/oneArgTypeinfo.kt
diff --git a/compiler/testData/codegen/typeInfo/primitiveTypeInfo.jet b/compiler/testData/codegen/typeInfo/primitiveTypeInfo.kt
similarity index 100%
rename from compiler/testData/codegen/typeInfo/primitiveTypeInfo.jet
rename to compiler/testData/codegen/typeInfo/primitiveTypeInfo.kt
diff --git a/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java
index cdc2bf150a9..dc81238015d 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java
@@ -29,16 +29,16 @@ public class ArrayGenTest extends CodegenTestCase {
     }
 
     public void testKt238() throws Exception {
-        blackBoxFile("regressions/kt238.jet");
+        blackBoxFile("regressions/kt238.kt");
     }
 
     public void testKt326() throws Exception {
-        //        blackBoxFile("regressions/kt326.jet");
+        //        blackBoxFile("regressions/kt326.kt");
         //        System.out.println(generateToText());
     }
 
     public void testKt779() throws Exception {
-        blackBoxFile("regressions/kt779.jet");
+        blackBoxFile("regressions/kt779.kt");
         //        System.out.println(generateToText());
     }
 
@@ -240,7 +240,7 @@ public class ArrayGenTest extends CodegenTestCase {
     }
 
     public void testCollectionPlusAssign() throws Exception {
-        blackBoxFile("regressions/kt33.jet");
+        blackBoxFile("regressions/kt33.kt");
     }
 
     public void testArrayPlusAssign() throws Exception {
@@ -310,26 +310,26 @@ public class ArrayGenTest extends CodegenTestCase {
     }
 
     public void testKt503() {
-        blackBoxFile("regressions/kt503.jet");
+        blackBoxFile("regressions/kt503.kt");
     }
 
     public void testKt602() {
-        blackBoxFile("regressions/kt602.jet");
+        blackBoxFile("regressions/kt602.kt");
         //        System.out.println(generateToText());
     }
 
     public void testKt950() {
-        blackBoxFile("regressions/kt950.jet");
+        blackBoxFile("regressions/kt950.kt");
     }
 
     public void testKt594() throws Exception {
-        loadFile("regressions/kt594.jet");
+        loadFile("regressions/kt594.kt");
         //        System.out.println(generateToText());
         blackBox();
     }
 
     public void testNonNullArray() throws Exception {
-        blackBoxFile("classes/nonnullarray.jet");
+        blackBoxFile("classes/nonnullarray.kt");
         //        System.out.println(generateToText());
     }
 
diff --git a/compiler/tests/org/jetbrains/jet/codegen/BridgeMethodGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/BridgeMethodGenTest.java
index 465fdf2bc4c..245dfdf588f 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/BridgeMethodGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/BridgeMethodGenTest.java
@@ -22,7 +22,7 @@ public class BridgeMethodGenTest extends CodegenTestCase {
 
     public void testBridgeMethod () throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("bridge.jet");
+        blackBoxFile("bridge.kt");
     }
 
     public void testKt1959() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/ClassGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/ClassGenTest.java
index cc1119deaf3..b23300f782e 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/ClassGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/ClassGenTest.java
@@ -34,7 +34,7 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testPSVMClass() {
-        loadFile("classes/simpleClass.jet");
+        loadFile("classes/simpleClass.kt");
 
         final Class aClass = loadClass("SimpleClass", generateClassesInFile());
         final Method[] methods = aClass.getDeclaredMethods();
@@ -44,7 +44,7 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testArrayListInheritance() throws Exception {
-        loadFile("classes/inheritingFromArrayList.jet");
+        loadFile("classes/inheritingFromArrayList.kt");
         final Class aClass = loadClass("Foo", generateClassesInFile());
         assertInstanceOf(aClass.newInstance(), List.class);
     }
@@ -84,7 +84,7 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testInheritanceAndDelegation_DelegatingDefaultConstructorProperties() {
-        blackBoxFile("classes/inheritance.jet");
+        blackBoxFile("classes/inheritance.kt");
     }
 
     public void testInheritanceAndDelegation2() {
@@ -120,34 +120,34 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testFunDelegation() {
-        blackBoxFile("classes/funDelegation.jet");
+        blackBoxFile("classes/funDelegation.kt");
     }
 
     public void testPropertyDelegation() {
-        blackBoxFile("classes/propertyDelegation.jet");
+        blackBoxFile("classes/propertyDelegation.kt");
     }
 
     public void testDiamondInheritance() {
-        blackBoxFile("classes/diamondInheritance.jet");
+        blackBoxFile("classes/diamondInheritance.kt");
     }
 
     public void testRightHandOverride() {
-        blackBoxFile("classes/rightHandOverride.jet");
+        blackBoxFile("classes/rightHandOverride.kt");
     }
 
     public void testNewInstanceExplicitConstructor() throws Exception {
-        loadFile("classes/newInstanceDefaultConstructor.jet");
+        loadFile("classes/newInstanceDefaultConstructor.kt");
         final Method method = generateFunction("test");
         final Integer returnValue = (Integer) method.invoke(null);
         assertEquals(610, returnValue.intValue());
     }
 
     public void testInnerClass() {
-        blackBoxFile("classes/innerClass.jet");
+        blackBoxFile("classes/innerClass.kt");
     }
 
     public void testInheritedInnerClass() {
-        blackBoxFile("classes/inheritedInnerClass.jet");
+        blackBoxFile("classes/inheritedInnerClass.kt");
     }
 
     public void testKt2532() {
@@ -155,7 +155,7 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testInitializerBlock() {
-        blackBoxFile("classes/initializerBlock.jet");
+        blackBoxFile("classes/initializerBlock.kt");
     }
 
     public void testAbstractMethod() throws Exception {
@@ -167,27 +167,27 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testInheritedMethod() {
-        blackBoxFile("classes/inheritedMethod.jet");
+        blackBoxFile("classes/inheritedMethod.kt");
     }
 
     public void testInitializerBlockDImpl() {
-        blackBoxFile("classes/initializerBlockDImpl.jet");
+        blackBoxFile("classes/initializerBlockDImpl.kt");
     }
 
     public void testPropertyInInitializer() {
-        blackBoxFile("classes/propertyInInitializer.jet");
+        blackBoxFile("classes/propertyInInitializer.kt");
     }
 
     public void testOuterThis() {
-        blackBoxFile("classes/outerThis.jet");
+        blackBoxFile("classes/outerThis.kt");
     }
 
     public void testExceptionConstructor() {
-        blackBoxFile("classes/exceptionConstructor.jet");
+        blackBoxFile("classes/exceptionConstructor.kt");
     }
 
     public void testSimpleBox() {
-        blackBoxFile("classes/simpleBox.jet");
+        blackBoxFile("classes/simpleBox.kt");
     }
 
     public void testAbstractClass() throws Exception {
@@ -197,45 +197,45 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testClassObject() {
-        blackBoxFile("classes/classObject.jet");
+        blackBoxFile("classes/classObject.kt");
     }
 
     public void testClassObjectInTrait() {
-        blackBoxFile("classes/classObjectInTrait.jet");
+        blackBoxFile("classes/classObjectInTrait.kt");
     }
 
     /*
     public void testClassObjectMethod() {
         // todo to be implemented after removal of type info
-        //        blackBoxFile("classes/classObjectMethod.jet");
+        //        blackBoxFile("classes/classObjectMethod.kt");
     }
     */
 
     public void testClassObjectInterface() throws Exception {
-        loadFile("classes/classObjectInterface.jet");
+        loadFile("classes/classObjectInterface.kt");
         final Method method = generateFunction();
         Object result = method.invoke(null);
         assertInstanceOf(result, Runnable.class);
     }
 
     public void testOverloadBinaryOperator() {
-        blackBoxFile("classes/overloadBinaryOperator.jet");
+        blackBoxFile("classes/overloadBinaryOperator.kt");
     }
 
     public void testOverloadUnaryOperator() {
-        blackBoxFile("classes/overloadUnaryOperator.jet");
+        blackBoxFile("classes/overloadUnaryOperator.kt");
     }
 
     public void testOverloadPlusAssign() {
-        blackBoxFile("classes/overloadPlusAssign.jet");
+        blackBoxFile("classes/overloadPlusAssign.kt");
     }
 
     public void testOverloadPlusAssignReturn() {
-        blackBoxFile("classes/overloadPlusAssignReturn.jet");
+        blackBoxFile("classes/overloadPlusAssignReturn.kt");
     }
 
     public void testOverloadPlusToPlusAssign() {
-        blackBoxFile("classes/overloadPlusToPlusAssign.jet");
+        blackBoxFile("classes/overloadPlusToPlusAssign.kt");
     }
 
     public void testEnumClass() throws Exception {
@@ -270,11 +270,11 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testKt249() {
-        blackBoxFile("regressions/kt249.jet");
+        blackBoxFile("regressions/kt249.kt");
     }
 
     public void testKt48() {
-        blackBoxFile("regressions/kt48.jet");
+        blackBoxFile("regressions/kt48.kt");
     }
 
     public void testKt309() {
@@ -284,39 +284,39 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testKt343() {
-        blackBoxFile("regressions/kt343.jet");
+        blackBoxFile("regressions/kt343.kt");
     }
 
     public void testKt508() {
-        blackBoxFile("regressions/kt508.jet");
+        blackBoxFile("regressions/kt508.kt");
     }
 
     public void testKt504() {
-        blackBoxFile("regressions/kt504.jet");
+        blackBoxFile("regressions/kt504.kt");
     }
 
     public void testKt501() {
-        blackBoxFile("regressions/kt501.jet");
+        blackBoxFile("regressions/kt501.kt");
     }
 
     public void testKt496() {
-        blackBoxFile("regressions/kt496.jet");
+        blackBoxFile("regressions/kt496.kt");
     }
 
     public void testKt500() {
-        blackBoxFile("regressions/kt500.jet");
+        blackBoxFile("regressions/kt500.kt");
     }
 
     public void testKt285() {
-        blackBoxFile("regressions/kt285.jet");
+        blackBoxFile("regressions/kt285.kt");
     }
 
     public void testKt707() {
-        blackBoxFile("regressions/kt707.jet");
+        blackBoxFile("regressions/kt707.kt");
     }
 
     public void testKt903() {
-        blackBoxFile("regressions/kt903.jet");
+        blackBoxFile("regressions/kt903.kt");
     }
 
     public void testKt940() {
@@ -378,7 +378,7 @@ public class ClassGenTest extends CodegenTestCase {
     }
 
     public void testResolveOrder() {
-        blackBoxFile("classes/resolveOrder.jet");
+        blackBoxFile("classes/resolveOrder.kt");
     }
 
     public void testKt1918() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/ClosuresGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/ClosuresGenTest.java
index fe50d12f6f4..22404d84ec9 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/ClosuresGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/ClosuresGenTest.java
@@ -27,37 +27,37 @@ public class ClosuresGenTest extends CodegenTestCase {
     }
 
     public void testSimplestClosure() throws Exception {
-        blackBoxFile("classes/simplestClosure.jet");
+        blackBoxFile("classes/simplestClosure.kt");
 //        System.out.println(generateToText());
     }
 
     public void testSimplestClosureAndBoxing() throws Exception {
-        blackBoxFile("classes/simplestClosureAndBoxing.jet");
+        blackBoxFile("classes/simplestClosureAndBoxing.kt");
     }
 
     public void testClosureWithParameter() throws Exception {
-        blackBoxFile("classes/closureWithParameter.jet");
+        blackBoxFile("classes/closureWithParameter.kt");
     }
 
     public void testClosureWithParameterAndBoxing() throws Exception {
-        blackBoxFile("classes/closureWithParameterAndBoxing.jet");
+        blackBoxFile("classes/closureWithParameterAndBoxing.kt");
     }
 
     public void testExtensionClosure() throws Exception {
-        blackBoxFile("classes/extensionClosure.jet");
+        blackBoxFile("classes/extensionClosure.kt");
     }
 
     public void testEnclosingLocalVariable() throws Exception {
-        blackBoxFile("classes/enclosingLocalVariable.jet");
+        blackBoxFile("classes/enclosingLocalVariable.kt");
 //        System.out.println(generateToText());
     }
 
     public void testDoubleEnclosedLocalVariable() throws Exception {
-        blackBoxFile("classes/doubleEnclosedLocalVariable.jet");
+        blackBoxFile("classes/doubleEnclosedLocalVariable.kt");
     }
 
     public void testEnclosingThis() throws Exception {
-        blackBoxFile("classes/enclosingThis.jet");
+        blackBoxFile("classes/enclosingThis.kt");
     }
 
     public void testKt2151() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java b/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java
index f9626e6ffd9..82681d8d751 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java
@@ -144,7 +144,7 @@ public abstract class CodegenTestCase extends UsefulTestCase {
     }
 
     protected void loadFile() {
-        loadFile(getPrefix() + "/" + getTestName(true) + ".jet");
+        loadFile(getPrefix() + "/" + getTestName(true) + ".kt");
     }
 
     protected String getPrefix() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/ControlStructuresTest.java b/compiler/tests/org/jetbrains/jet/codegen/ControlStructuresTest.java
index 5730bde3a30..41bb96957fe 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/ControlStructuresTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/ControlStructuresTest.java
@@ -50,21 +50,21 @@ public class ControlStructuresTest extends CodegenTestCase {
     }
 
     public void testWhile() throws Exception {
-        factorialTest("controlStructures/while.jet");
+        factorialTest("controlStructures/while.kt");
     }
 
     public void testDoWhile() throws Exception {
-        factorialTest("controlStructures/doWhile.jet");
+        factorialTest("controlStructures/doWhile.kt");
     }
 
     public void testBreak() throws Exception {
-        factorialTest("controlStructures/break.jet");
+        factorialTest("controlStructures/break.kt");
     }
 
     /*
     public void testInRangeConditionsInWhen() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/inRangeConditionsInWhen.jet");
+        blackBoxFile("controlStructures/inRangeConditionsInWhen.kt");
     }
     */
 
@@ -188,7 +188,7 @@ public class ControlStructuresTest extends CodegenTestCase {
 
     public void testForUserType() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/forUserType.jet");
+        blackBoxFile("controlStructures/forUserType.kt");
     }
 
     public void testForLoopMemberExtensionNext() throws Exception {
@@ -208,27 +208,27 @@ public class ControlStructuresTest extends CodegenTestCase {
 
     public void testForIntArray() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/forIntArray.jet");
+        blackBoxFile("controlStructures/forIntArray.kt");
     }
 
     public void testForPrimitiveIntArray() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/forPrimitiveIntArray.jet");
+        blackBoxFile("controlStructures/forPrimitiveIntArray.kt");
     }
 
     public void testForNullableIntArray() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/forNullableIntArray.jet");
+        blackBoxFile("controlStructures/forNullableIntArray.kt");
     }
 
     public void testForIntRange() {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/forIntRange.jet");
+        blackBoxFile("controlStructures/forIntRange.kt");
     }
 
     public void testKt237() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt237.jet");
+        blackBoxFile("regressions/kt237.kt");
     }
 
     public void testCompareToZero() throws Exception {
@@ -285,70 +285,70 @@ public class ControlStructuresTest extends CodegenTestCase {
 
     public void testKt299() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt299.jet");
+        blackBoxFile("regressions/kt299.kt");
     }
 
     public void testKt416() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt416.jet");
+        blackBoxFile("regressions/kt416.kt");
 //        System.out.println(generateToText());
     }
 
     public void testKt513() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt513.jet");
+        blackBoxFile("regressions/kt513.kt");
     }
 
     public void testKt434() throws Exception {
         createEnvironmentWithFullJdk();
-        blackBoxFile("regressions/kt434.jet");
+        blackBoxFile("regressions/kt434.kt");
     }
 
     public void testKt769() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt769.jet");
+        blackBoxFile("regressions/kt769.kt");
 //        System.out.println(generateToText());
     }
 
     public void testKt773() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt773.jet");
+        blackBoxFile("regressions/kt773.kt");
 //        System.out.println(generateToText());
     }
 
     public void testKt772() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt772.jet");
+        blackBoxFile("regressions/kt772.kt");
 //        System.out.println(generateToText());
     }
 
     public void testKt870() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt870.jet");
+        blackBoxFile("regressions/kt870.kt");
 //        System.out.println(generateToText());
     }
 
     public void testKt958() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt958.jet");
+        blackBoxFile("regressions/kt958.kt");
 //        System.out.println(generateToText());
     }
 
     public void testQuicksort() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/quicksort.jet");
+        blackBoxFile("controlStructures/quicksort.kt");
 //        System.out.println(generateToText());
     }
 
     public void testSynchronized() throws Exception {
         createEnvironmentWithFullJdk();
-        blackBoxFile("controlStructures/sync.jet");
+        blackBoxFile("controlStructures/sync.kt");
 //        System.out.println(generateToText());
     }
 
     public void testIfInWhile() throws Exception {
         createEnvironmentWithFullJdk();
-        blackBoxFile("controlStructures/ifInWhile.jet");
+        blackBoxFile("controlStructures/ifInWhile.kt");
 //        System.out.println(generateToText());
     }
 
@@ -454,7 +454,7 @@ public class ControlStructuresTest extends CodegenTestCase {
 
     public void testLongRange() {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("controlStructures/longRange.jet");
+        blackBoxFile("controlStructures/longRange.kt");
     }
 
     public void testForInSmartCastedToArray() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/ExtensionFunctionsTest.java b/compiler/tests/org/jetbrains/jet/codegen/ExtensionFunctionsTest.java
index add65877c7b..4156ed0bf6e 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/ExtensionFunctionsTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/ExtensionFunctionsTest.java
@@ -44,7 +44,7 @@ public class ExtensionFunctionsTest extends CodegenTestCase {
 
     public void testVirtual() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("extensionFunctions/virtual.jet");
+        blackBoxFile("extensionFunctions/virtual.kt");
     }
 
     public void testShared() throws Exception {
@@ -55,7 +55,7 @@ public class ExtensionFunctionsTest extends CodegenTestCase {
 
     public void testKt475() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt475.jet");
+        blackBoxFile("regressions/kt475.kt");
     }
 
     public void testKtNested() throws Exception {
@@ -65,7 +65,7 @@ public class ExtensionFunctionsTest extends CodegenTestCase {
 
     public void testKt865() throws Exception {
         createEnvironmentWithFullJdk();
-        blackBoxFile("regressions/kt865.jet");
+        blackBoxFile("regressions/kt865.kt");
     }
 
     public void testKtNested2() throws Exception {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/FunctionGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/FunctionGenTest.java
index 84eea7c8fe5..1d24054bde2 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/FunctionGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/FunctionGenTest.java
@@ -35,32 +35,32 @@ public class FunctionGenTest extends CodegenTestCase {
     }
 
     public void testDefaultArgs() throws Exception {
-        blackBoxFile("functions/defaultargs.jet");
+        blackBoxFile("functions/defaultargs.kt");
         //        System.out.println(generateToText());
     }
 
     public void testDefaultArgs1() throws Exception {
-        blackBoxFile("functions/defaultargs1.jet");
+        blackBoxFile("functions/defaultargs1.kt");
         //        System.out.println(generateToText());
     }
 
     public void testDefaultArgs2() throws Exception {
-        blackBoxFile("functions/defaultargs2.jet");
+        blackBoxFile("functions/defaultargs2.kt");
         //        System.out.println(generateToText());
     }
 
     public void testDefaultArgs3() throws Exception {
-        blackBoxFile("functions/defaultargs3.jet");
+        blackBoxFile("functions/defaultargs3.kt");
         //        System.out.println(generateToText());
     }
 
     public void testDefaultArgs4() throws Exception {
-        blackBoxFile("functions/defaultargs4.jet");
+        blackBoxFile("functions/defaultargs4.kt");
         //        System.out.println(generateToText());
     }
 
     public void testDefaultArgs5() throws Exception {
-        blackBoxFile("functions/defaultargs5.jet");
+        blackBoxFile("functions/defaultargs5.kt");
         //        System.out.println(generateToText());
     }
 
@@ -73,7 +73,7 @@ public class FunctionGenTest extends CodegenTestCase {
     }
 
     public void testNoThisNoClosure() throws Exception {
-        blackBoxFile("functions/nothisnoclosure.jet");
+        blackBoxFile("functions/nothisnoclosure.kt");
         //        System.out.println(generateToText());
     }
 
@@ -107,11 +107,11 @@ public class FunctionGenTest extends CodegenTestCase {
     }
 
     public void testKt395() {
-        blackBoxFile("regressions/kt395.jet");
+        blackBoxFile("regressions/kt395.kt");
     }
 
     public void testKt785() {
-        blackBoxFile("regressions/kt785.jet");
+        blackBoxFile("regressions/kt785.kt");
     }
 
     public void testKt873() {
@@ -128,7 +128,7 @@ public class FunctionGenTest extends CodegenTestCase {
     }
 
     public void testFunction() throws InvocationTargetException, IllegalAccessException {
-        blackBoxFile("functions/functionExpression.jet");
+        blackBoxFile("functions/functionExpression.kt");
     }
 
     public void testLocalFunction() throws InvocationTargetException, IllegalAccessException {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/NamespaceGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/NamespaceGenTest.java
index a188ef67a04..2412c3fc51a 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/NamespaceGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/NamespaceGenTest.java
@@ -33,7 +33,7 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testPSVM() throws Exception {
-        loadFile("PSVM.jet");
+        loadFile("PSVM.kt");
 //        System.out.println(generateToText());
 
         final Method main = generateFunction();
@@ -60,7 +60,7 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testLocalProperty() throws Exception {
-        loadFile("localProperty.jet");
+        loadFile("localProperty.kt");
 //        System.out.println(generateToText());
 
         final Method main = generateFunction();
@@ -86,14 +86,14 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testSystemOut() throws Exception {
-        loadFile("systemOut.jet");
+        loadFile("systemOut.kt");
         final Method main = generateFunction();
         final Object returnValue = main.invoke(null);
         assertEquals(returnValue, System.out);
     }
 
     public void testHelloWorld() throws Exception {
-        loadFile("helloWorld.jet");
+        loadFile("helloWorld.kt");
 
 //        System.out.println(generateToText());
 
@@ -101,7 +101,7 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testAssign() throws Exception {
-        loadFile("assign.jet");
+        loadFile("assign.kt");
 
 //        System.out.println(generateToText());
         final Method main = generateFunction();
@@ -185,7 +185,7 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testBottles2() throws Exception {
-        loadFile("bottles2.jet");
+        loadFile("bottles2.kt");
 //        System.out.println(generateToText());
         final Method main = generateFunction();
         main.invoke(null);  // ensure no exception
@@ -257,7 +257,7 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testFunctionCall() throws Exception {
-        loadFile("functionCall.jet");
+        loadFile("functionCall.kt");
 //        System.out.println(generateToText());
         final Method main = generateFunction("f");
         assertEquals("foo", main.invoke(null));
@@ -467,15 +467,15 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testNamespaceQualifiedMethod() throws Exception {
-        blackBoxFile("namespaceQualifiedMethod.jet");
+        blackBoxFile("namespaceQualifiedMethod.kt");
     }
 
     public void testCheckCast() throws Exception {
-        blackBoxFile("checkCast.jet");
+        blackBoxFile("checkCast.kt");
     }
 
     public void testTypeCastException() throws Exception {
-        blackBoxFile("typeCastException.jet");
+        blackBoxFile("typeCastException.kt");
     }
 
     public void testPutBooleanAsVoid() throws Exception {
@@ -485,7 +485,7 @@ public class NamespaceGenTest extends CodegenTestCase {
     }
 
     public void testIncrementProperty() throws Exception {
-        blackBoxFile("incrementProperty.jet");
+        blackBoxFile("incrementProperty.kt");
     }
 
     public void testJavaInterfaceMethod() throws Exception {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/ObjectGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/ObjectGenTest.java
index e6c634bb283..e7ebb142723 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/ObjectGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/ObjectGenTest.java
@@ -26,34 +26,34 @@ public class ObjectGenTest extends CodegenTestCase {
     }
 
     public void testSimpleObject() {
-        blackBoxFile("objects/simpleObject.jet");
+        blackBoxFile("objects/simpleObject.kt");
 //        System.out.println(generateToText());
     }
 
     public void testObjectLiteral() {
-        blackBoxFile("objects/objectLiteral.jet");
+        blackBoxFile("objects/objectLiteral.kt");
 //        System.out.println(generateToText());
     }
 
     public void testObjectLiteralInClosure() {
-        blackBoxFile("objects/objectLiteralInClosure.jet");
+        blackBoxFile("objects/objectLiteralInClosure.kt");
 //        System.out.println(generateToText());
     }
 
     public void testMethodOnObject() {
-        blackBoxFile("objects/methodOnObject.jet");
+        blackBoxFile("objects/methodOnObject.kt");
     }
 
     public void testKt535() {
-        blackBoxFile("regressions/kt535.jet");
+        blackBoxFile("regressions/kt535.kt");
     }
 
     public void testKt560() {
-        blackBoxFile("regressions/kt560.jet");
+        blackBoxFile("regressions/kt560.kt");
     }
 
     public void testKt640() {
-        blackBoxFile("regressions/kt640.jet");
+        blackBoxFile("regressions/kt640.kt");
     }
 
     public void testKt1136() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/PatternMatchingTest.java b/compiler/tests/org/jetbrains/jet/codegen/PatternMatchingTest.java
index e559acabbb1..d2e1d20ccb8 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/PatternMatchingTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/PatternMatchingTest.java
@@ -73,11 +73,11 @@ public class PatternMatchingTest extends CodegenTestCase {
     }
 
     public void testRange() throws Exception {
-        blackBoxFile("patternMatching/range.jet");
+        blackBoxFile("patternMatching/range.kt");
     }
 
     public void testLongInRange() throws Exception {
-        blackBoxFile("patternMatching/longInRange.jet");
+        blackBoxFile("patternMatching/longInRange.kt");
     }
 
     public void testWhenArgumentIsEvaluatedOnlyOnce() throws Exception {
@@ -112,7 +112,7 @@ public class PatternMatchingTest extends CodegenTestCase {
     }
 
     public void testCallProperty() throws Exception {
-        blackBoxFile("patternMatching/callProperty.jet");
+        blackBoxFile("patternMatching/callProperty.kt");
     }
 
     public void testMultipleConditions() throws Exception {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java b/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java
index ebd641a012d..989f692fe0d 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java
@@ -269,7 +269,7 @@ public class PrimitiveTypesTest extends CodegenTestCase {
     }
 
     public void testDecrementAsStatement() throws Exception {
-        loadFile("bottles.jet");
+        loadFile("bottles.kt");
 //        System.out.println(generateToText());
         final Method main = generateFunction();
         main.invoke(null);  // ensure no exception
@@ -283,31 +283,31 @@ public class PrimitiveTypesTest extends CodegenTestCase {
     }
 
     public void testEa35963() {
-        blackBoxFile("regressions/ea35963.jet");
+        blackBoxFile("regressions/ea35963.kt");
     }
 
     public void testKt242 () throws Exception {
-        blackBoxFile("regressions/kt242.jet");
+        blackBoxFile("regressions/kt242.kt");
     }
 
     public void testKt239 () throws Exception {
-        blackBoxFile("regressions/kt239.jet");
+        blackBoxFile("regressions/kt239.kt");
     }
 
     public void testKt243 () throws Exception {
-        blackBoxFile("regressions/kt243.jet");
+        blackBoxFile("regressions/kt243.kt");
     }
 
     public void testKt248 () throws Exception {
-        blackBoxFile("regressions/kt248.jet");
+        blackBoxFile("regressions/kt248.kt");
     }
 
     public void testKt446 () throws Exception {
-        blackBoxFile("regressions/kt446.jet");
+        blackBoxFile("regressions/kt446.kt");
     }
 
     public void testKt518 () throws Exception {
-        blackBoxFile("regressions/kt518.jet");
+        blackBoxFile("regressions/kt518.kt");
     }
 
     public void testKt711 () throws Exception {
@@ -357,36 +357,36 @@ public class PrimitiveTypesTest extends CodegenTestCase {
     }
 
     public void testKt752 () {
-        blackBoxFile("regressions/kt752.jet");
+        blackBoxFile("regressions/kt752.kt");
     }
 
     public void testKt753 () {
-        blackBoxFile("regressions/kt753.jet");
+        blackBoxFile("regressions/kt753.kt");
     }
 
     public void testKt684 () {
-        blackBoxFile("regressions/kt684.jet");
+        blackBoxFile("regressions/kt684.kt");
     }
 
     public void testKt756 () {
-        blackBoxFile("regressions/kt756.jet");
+        blackBoxFile("regressions/kt756.kt");
         //System.out.println(generateToText());
     }
 
     public void testKt757 () {
-        blackBoxFile("regressions/kt757.jet");
+        blackBoxFile("regressions/kt757.kt");
     }
 
     public void testKt877 () {
-        blackBoxFile("regressions/kt877.jet");
+        blackBoxFile("regressions/kt877.kt");
     }
 
     public void testKt882 () {
-        blackBoxFile("regressions/kt882.jet");
+        blackBoxFile("regressions/kt882.kt");
     }
 
     public void testKt887 () {
-        blackBoxFile("regressions/kt887.jet");
+        blackBoxFile("regressions/kt887.kt");
     }
 
     public void testKt821 () {
@@ -406,7 +406,7 @@ public class PrimitiveTypesTest extends CodegenTestCase {
     }
 
     public void testKt945 () {
-        blackBoxFile("regressions/kt945.jet");
+        blackBoxFile("regressions/kt945.kt");
     }
 
     public void testKt935 () {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/PropertyGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/PropertyGenTest.java
index 423bfa7a65b..edcd064e8d2 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/PropertyGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/PropertyGenTest.java
@@ -82,7 +82,7 @@ public class PropertyGenTest extends CodegenTestCase {
 
     public void testFieldPropertyAccess() throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        loadFile("properties/fieldPropertyAccess.jet");
+        loadFile("properties/fieldPropertyAccess.kt");
 //        System.out.println(generateToText());
         final Method method = generateFunction("increment");
         assertEquals(1, method.invoke(null));
@@ -175,13 +175,13 @@ public class PropertyGenTest extends CodegenTestCase {
 
     public void testKt257 () throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt257.jet");
+        blackBoxFile("regressions/kt257.kt");
 //        System.out.println(generateToText());
     }
 
     public void testKt613 () throws Exception {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt613.jet");
+        blackBoxFile("regressions/kt613.kt");
     }
 
     public void testKt160() throws Exception {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/SafeRefTest.java b/compiler/tests/org/jetbrains/jet/codegen/SafeRefTest.java
index 0d05d8bf10a..f25722d8842 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/SafeRefTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/SafeRefTest.java
@@ -26,18 +26,18 @@ public class SafeRefTest extends CodegenTestCase {
     }
 
     public void test247 () throws Exception {
-        blackBoxFile("regressions/kt247.jet");
+        blackBoxFile("regressions/kt247.kt");
     }
 
     public void test245 () throws Exception {
-        blackBoxFile("regressions/kt245.jet");
+        blackBoxFile("regressions/kt245.kt");
     }
 
     public void test232 () throws Exception {
-        blackBoxFile("regressions/kt232.jet");
+        blackBoxFile("regressions/kt232.kt");
     }
 
     public void test1572 () throws Exception {
-        blackBoxFile("regressions/kt1572.jet");
+        blackBoxFile("regressions/kt1572.kt");
     }
 }
diff --git a/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java b/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java
index 087822005c2..fcb226e7dc5 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java
@@ -74,7 +74,7 @@ public class StdlibTest extends CodegenTestCase {
     }
 
     public void testKt789 () {
-        blackBoxFile("regressions/kt789.jet");
+        blackBoxFile("regressions/kt789.kt");
     }
 
     public void testKt828 () {
@@ -86,7 +86,7 @@ public class StdlibTest extends CodegenTestCase {
     }
 
     public void testKt864 () {
-        blackBoxFile("regressions/kt864.jet");
+        blackBoxFile("regressions/kt864.kt");
     }
 
     public void testKt274 () {
@@ -95,14 +95,14 @@ public class StdlibTest extends CodegenTestCase {
 
     //from ClassGenTest
     public void testKt344 () throws Exception {
-        loadFile("regressions/kt344.jet");
+        loadFile("regressions/kt344.kt");
 //        System.out.println(generateToText());
         blackBox();
     }
 
     //from ExtensionFunctionsTest
     public void testGeneric() throws Exception {
-        blackBoxFile("extensionFunctions/generic.jet");
+        blackBoxFile("extensionFunctions/generic.kt");
     }
 
     //from NamespaceGenTest
diff --git a/compiler/tests/org/jetbrains/jet/codegen/StringsTest.java b/compiler/tests/org/jetbrains/jet/codegen/StringsTest.java
index e2f95b305f2..6df980e40d8 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/StringsTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/StringsTest.java
@@ -70,23 +70,23 @@ public class StringsTest extends CodegenTestCase {
     }
 
     public void testRawStrings() throws Exception {
-        blackBoxFile("rawStrings.jet");
+        blackBoxFile("rawStrings.kt");
     }
 
     public void testMultilineStringsWithTemplates() throws Exception {
-        blackBoxFile("multilineStringsWithTemplates.jet");
+        blackBoxFile("multilineStringsWithTemplates.kt");
     }
 
     public void testKt881() throws Exception {
-        blackBoxFile("regressions/kt881.jet");
+        blackBoxFile("regressions/kt881.kt");
     }
 
     public void testKt894() throws Exception {
-        blackBoxFile("regressions/kt894.jet");
+        blackBoxFile("regressions/kt894.kt");
     }
 
     public void testKt889() throws Exception {
-        blackBoxFile("regressions/kt889.jet");
+        blackBoxFile("regressions/kt889.kt");
     }
 
     public void testEa35743() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/SuperGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/SuperGenTest.java
index 1dd278c3682..8bf1ab881d9 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/SuperGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/SuperGenTest.java
@@ -28,19 +28,19 @@ public class SuperGenTest extends CodegenTestCase {
     }
 
     public void testBasicProperty () {
-        blackBoxFile("/super/basicproperty.jet");
+        blackBoxFile("/super/basicproperty.kt");
     }
 
     public void testTraitProperty () {
-        blackBoxFile("/super/traitproperty.jet");
+        blackBoxFile("/super/traitproperty.kt");
     }
 
     public void testBasicMethodSuperTrait () {
-        blackBoxFile("/super/basicmethodSuperTrait.jet");
+        blackBoxFile("/super/basicmethodSuperTrait.kt");
     }
 
     public void testBasicMethodSuperClass () {
-        blackBoxFile("/super/basicmethodSuperClass.jet");
+        blackBoxFile("/super/basicmethodSuperClass.kt");
     }
 
     public void testInnerClassLabeledSuper() {
@@ -56,11 +56,11 @@ public class SuperGenTest extends CodegenTestCase {
     }
 
     public void testEnclosedFun () {
-        blackBoxFile("/super/enclosedFun.jet");
+        blackBoxFile("/super/enclosedFun.kt");
     }
 
     public void testEnclosedVar () {
-        blackBoxFile("/super/enclosedVar.jet");
+        blackBoxFile("/super/enclosedVar.kt");
     }
 
     public void testKt2887() {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/TraitsTest.java b/compiler/tests/org/jetbrains/jet/codegen/TraitsTest.java
index c1cc1330412..a33df3f0f78 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/TraitsTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/TraitsTest.java
@@ -32,29 +32,29 @@ public class TraitsTest extends CodegenTestCase {
     }
 
     public void testSimple () {
-        blackBoxFile("traits/simple.jet");
+        blackBoxFile("traits/simple.kt");
 //        System.out.println(generateToText());
     }
 
     public void testWithRequired () {
-        blackBoxFile("traits/withRequired.jet");
+        blackBoxFile("traits/withRequired.kt");
 //        System.out.println(generateToText());
     }
 
     public void testMultiple () {
-        blackBoxFile("traits/multiple.jet");
+        blackBoxFile("traits/multiple.kt");
     }
 
     public void testStdlib () {
-        blackBoxFile("traits/stdlib.jet");
+        blackBoxFile("traits/stdlib.kt");
     }
 
     public void testInheritedFun() {
-        blackBoxFile("traits/inheritedFun.jet");
+        blackBoxFile("traits/inheritedFun.kt");
     }
 
     public void testInheritedVar() {
-        blackBoxFile("traits/inheritedVar.jet");
+        blackBoxFile("traits/inheritedVar.kt");
     }
     
     public void testKt2399() {
@@ -74,7 +74,7 @@ public class TraitsTest extends CodegenTestCase {
     }
 
     public void testFinalMethod() throws Exception {
-        blackBoxFile("traits/finalMethod.jet");
+        blackBoxFile("traits/finalMethod.kt");
     }
 
     public void testKt1936_1() throws Exception {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java b/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java
index 5d30e267dac..27117d3cb74 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java
@@ -82,7 +82,7 @@ public class TypeInfoTest extends CodegenTestCase {
 
     public void testIsTypeParameter() throws Exception {
 //  todo: obsolete with typeinfo removal
-//        blackBoxFile("typeInfo/isTypeParameter.jet");
+//        blackBoxFile("typeInfo/isTypeParameter.kt");
     }
 
     public void testAsSafeWithGenerics() throws Exception {
@@ -98,22 +98,22 @@ public class TypeInfoTest extends CodegenTestCase {
     }
 
     public void testPrimitiveTypeInfo() throws Exception {
-        blackBoxFile("typeInfo/primitiveTypeInfo.jet");
+        blackBoxFile("typeInfo/primitiveTypeInfo.kt");
     }
 
     public void testNullability() throws Exception {
 //  todo: obsolete with typeinfo removal
-//        blackBoxFile("typeInfo/nullability.jet");
+//        blackBoxFile("typeInfo/nullability.kt");
     }
 
     public void testGenericFunction() throws Exception {
 //  todo: obsolete with typeinfo removal
-//        blackBoxFile("typeInfo/genericFunction.jet");
+//        blackBoxFile("typeInfo/genericFunction.kt");
     }
 
     public void testForwardTypeParameter() throws Exception {
 //  todo: obsolete with typeinfo removal
-//        blackBoxFile("typeInfo/forwardTypeParameter.jet");
+//        blackBoxFile("typeInfo/forwardTypeParameter.kt");
     }
 
     public void testClassObjectInTypeInfo() throws Exception {
@@ -139,17 +139,17 @@ public class TypeInfoTest extends CodegenTestCase {
 
     public void testKt259() throws Exception {
 //  todo: obsolete with typeinfo removal
-//        blackBoxFile("regressions/kt259.jet");
+//        blackBoxFile("regressions/kt259.kt");
 //        System.out.println(generateToText());
     }
 
     public void testKt511() throws Exception {
-        blackBoxFile("regressions/kt511.jet");
+        blackBoxFile("regressions/kt511.kt");
 //        System.out.println(generateToText());
     }
 
     public void testInner() throws Exception {
-        blackBoxFile("typeInfo/inner.jet");
+        blackBoxFile("typeInfo/inner.kt");
 //        System.out.println(generateToText());
     }
 
@@ -158,7 +158,7 @@ public class TypeInfoTest extends CodegenTestCase {
     }
 
     public void testInheritance() throws Exception {
-        blackBoxFile("typeInfo/inheritance.jet");
+        blackBoxFile("typeInfo/inheritance.kt");
 //        System.out.println(generateToText());
     }
 
diff --git a/compiler/tests/org/jetbrains/jet/codegen/VarArgTest.java b/compiler/tests/org/jetbrains/jet/codegen/VarArgTest.java
index 14193f43f8b..26aa7b2c374 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/VarArgTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/VarArgTest.java
@@ -95,12 +95,12 @@ public class VarArgTest extends CodegenTestCase {
 
     public void testKt581() {
         createEnvironmentWithFullJdk();
-        blackBoxFile("regressions/kt581.jet");
+        blackBoxFile("regressions/kt581.kt");
     }
 
     public void testKt797() {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
-        blackBoxFile("regressions/kt796_797.jet");
+        blackBoxFile("regressions/kt796_797.kt");
     }
 
     public void testArrayAsVararg () throws InvocationTargetException, IllegalAccessException {