Add getSignificantElement method in JetCodeFragment

compiler/frontend/src/org/jetbrains/jet/lang/psi/JetBlockCodeFragment.kt

@@ -27,5 +27,6 @@ public class JetBlockCodeFragment(
         context: PsiElement?
 ) : JetCodeFragment(project, name, text, JetNodeTypes.BLOCK_CODE_FRAGMENT, context) {
 
-    fun getBlock() = findChildByClass(javaClass<JetBlockExpression>()) ?: throw IllegalStateException("Block expression should be parsed for BlockCodeFragment")
+    override fun getSignificantElement() = findChildByClass(javaClass<JetBlockExpression>())
+                                                ?: throw IllegalStateException("Block expression should be parsed for BlockCodeFragment")
 }

compiler/frontend/src/org/jetbrains/jet/lang/psi/JetCodeFragment.kt

@@ -50,6 +50,8 @@ public abstract class JetCodeFragment(
     private var _superType: PsiType? = null
     private var _exceptionHandler: JavaCodeFragment.ExceptionHandler? = null
 
+    public abstract fun getSignificantElement(): JetElement?
+
     override fun forceResolveScope(scope: GlobalSearchScope?) {
         _resolveScope = scope
     }

compiler/frontend/src/org/jetbrains/jet/lang/psi/JetExpressionCodeFragment.kt

@@ -30,5 +30,5 @@ public class JetExpressionCodeFragment(
         context: PsiElement?
 ) : JetCodeFragment(project, name, text, JetNodeTypes.EXPRESSION_CODE_FRAGMENT, context) {
 
-    fun getExpression() = findChildByClass(javaClass<JetExpression>())
+    override fun getSignificantElement() = findChildByClass(javaClass<JetExpression>())
 }

compiler/frontend/src/org/jetbrains/jet/lang/psi/JetTypeCodeFragment.java

@@ -30,11 +30,17 @@ public class JetTypeCodeFragment extends JetCodeFragment {
 
     @Nullable
     public JetType getType() {
-        JetTypeReference typeReference = findChildByClass(JetTypeReference.class);
-        if (typeReference != null) {
+        JetElement typeReference = getSignificantElement();
+        if (typeReference instanceof JetTypeReference) {
             //TODO return the actual type
             return KotlinBuiltIns.getInstance().getAnyType();
         }
         return null;
     }
+
+    @Nullable
+    @Override
+    public JetElement getSignificantElement() {
+        return findChildByClass(JetTypeReference.class);
+    }
 }

idea/src/org/jetbrains/jet/plugin/debugger/evaluate/KotlinEvaluationBuilder.kt

@@ -254,11 +254,7 @@ fun addDebugExpressionBeforeContextElement(codeFragment: JetCodeFragment, contex
 
     parent.addBefore(JetPsiFactory.createNewLine(contextElement.getProject()), contextElement)
 
-    val debugExpression = when(codeFragment) {
-        is JetExpressionCodeFragment -> codeFragment.getExpression()
-        is JetBlockCodeFragment -> codeFragment.getBlock()
-        else -> null
-    }
+    val debugExpression = codeFragment.getSignificantElement()
     if (debugExpression == null) return null
 
     val newDebugExpression = parent.addBefore(debugExpression, contextElement)

idea/src/org/jetbrains/jet/plugin/project/ResolveElementCache.java

@@ -218,14 +218,8 @@ public class ResolveElementCache {
             JetCodeFragment codeFragment,
             BindingTrace trace
     ) {
-        JetExpression codeFragmentExpression = null;
-        if (codeFragment instanceof JetExpressionCodeFragment) {
-            codeFragmentExpression = ((JetExpressionCodeFragment) codeFragment).getExpression();
-        }
-        else if (codeFragment instanceof JetBlockCodeFragment) {
-            codeFragmentExpression = ((JetBlockCodeFragment) codeFragment).getBlock();
-        }
-        if (codeFragmentExpression == null) return;
+        JetElement codeFragmentExpression = codeFragment.getSignificantElement();
+        if (!(codeFragmentExpression instanceof JetExpression)) return;
 
         PsiElement contextElement = codeFragment.getContext();
         if (!(contextElement instanceof JetExpression)) return;
@@ -245,7 +239,7 @@ public class ResolveElementCache {
 
             DataFlowInfo dataFlowInfoForContextElement = contextForElement.get(BindingContext.EXPRESSION_DATA_FLOW_INFO, contextExpression);
             AnalyzerPackage.computeTypeInContext(
-                    codeFragmentExpression,
+                    (JetExpression) codeFragmentExpression,
                     chainedScope,
                     trace,
                     dataFlowInfoForContextElement == null ? DataFlowInfo.EMPTY : dataFlowInfoForContextElement,