Debugger: remove while loop

#KT-10043 Fixed

idea/src/org/jetbrains/kotlin/idea/codeInsight/CodeInsightUtils.java

@@ -48,7 +48,7 @@ public class CodeInsightUtils {
 
     @Nullable
     public static KtExpression findExpression(@NotNull PsiFile file, int startOffset, int endOffset) {
-        PsiElement element = findElementOfClassAtRange(file, startOffset, endOffset, KtExpression.class);
+        KtExpression element = findElementOfClassAtRange(file, startOffset, endOffset, KtExpression.class);
         if (element == null) return null;
 
         // TODO: Support binary operations in "Introduce..." refactorings
@@ -73,7 +73,7 @@ public class CodeInsightUtils {
             }
         }
 
-        KtExpression expression = (KtExpression) element;
+        KtExpression expression = element;
 
         BindingContext context = ResolutionUtils.analyze(expression);
 
@@ -136,7 +136,7 @@ public class CodeInsightUtils {
     }
 
     @Nullable
-    public static PsiElement findElementOfClassAtRange(@NotNull PsiFile file, int startOffset, int endOffset, Class<KtExpression> aClass) {
+    public static <T extends PsiElement> T findElementOfClassAtRange(@NotNull PsiFile file, int startOffset, int endOffset, Class<T> aClass) {
         // When selected range is this@Fo<select>o</select> we'd like to return `@Foo`
         // But it's PSI looks like: (AT IDENTIFIER):JetLabel
         // So if we search parent starting exactly at IDENTIFIER then we find nothing
@@ -149,13 +149,13 @@ public class CodeInsightUtils {
         startOffset = element1.getTextRange().getStartOffset();
         endOffset = element2.getTextRange().getEndOffset();
 
-        KtExpression ktExpression = PsiTreeUtil.findElementOfClassAtRange(file, startOffset, endOffset, aClass);
-        if (ktExpression == null ||
-            ktExpression.getTextRange().getStartOffset() != startOffset ||
-            ktExpression.getTextRange().getEndOffset() != endOffset) {
+        T newElement = PsiTreeUtil.findElementOfClassAtRange(file, startOffset, endOffset, aClass);
+        if (newElement == null ||
+            newElement.getTextRange().getStartOffset() != startOffset ||
+            newElement.getTextRange().getEndOffset() != endOffset) {
             return null;
         }
-        return ktExpression;
+        return newElement;
     }
 
     private static PsiElement getParentLabelOrElement(@Nullable PsiElement element) {

idea/src/org/jetbrains/kotlin/idea/debugger/evaluate/extractFunctionForDebuggerUtil.kt

@@ -34,6 +34,8 @@ import org.jetbrains.kotlin.idea.util.application.runReadAction
 import org.jetbrains.kotlin.idea.util.psi.patternMatching.toRange
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.codeFragmentUtil.suppressDiagnosticsInDebugMode
+import org.jetbrains.kotlin.psi.psiUtil.endOffset
+import org.jetbrains.kotlin.psi.psiUtil.startOffset
 
 fun getFunctionForExtractedFragment(
         codeFragment: KtCodeFragment,
@@ -138,12 +140,7 @@ private fun addImportsToFile(newImportList: KtImportList?, tmpFile: KtFile) {
 }
 
 private fun KtFile.getElementInCopy(e: PsiElement): PsiElement? {
-    val offset = e.textRange?.startOffset ?: return null
-    var elementAt = this.findElementAt(offset)
-    while (elementAt == null || elementAt.textRange?.endOffset != e.textRange?.endOffset) {
-        elementAt = elementAt?.parent
-    }
-    return elementAt
+    return CodeInsightUtils.findElementOfClassAtRange(this, e.startOffset, e.endOffset, e.javaClass)
 }
 
 private fun getExpressionToAddDebugExpressionBefore(tmpFile: KtFile, contextElement: PsiElement?, line: Int): PsiElement? {