Correct range recalculation during comment formatting

java/java-impl/src/com/intellij/psi/formatter/java/DocCommentBlock.java

@@ -18,9 +18,9 @@ package com.intellij.psi.formatter.java;
 import com.intellij.formatting.*;
 import com.intellij.formatting.alignment.AlignmentStrategy;
 import com.intellij.lang.ASTNode;
+import com.intellij.psi.JavaDocTokenType;
 import com.intellij.psi.codeStyle.CommonCodeStyleSettings;
 import com.intellij.psi.formatter.FormatterUtil;
-import com.intellij.psi.impl.source.tree.ElementType;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
@@ -37,7 +37,7 @@ public class DocCommentBlock extends AbstractJavaBlock{
 
     ASTNode child = myNode.getFirstChildNode();
     while (child != null) {
-      if (child.getElementType() == ElementType.DOC_COMMENT_START) {
+      if (child.getElementType() == JavaDocTokenType.DOC_COMMENT_START) {
         result.add(createJavaBlock(child, mySettings, Indent.getNoneIndent(), null, AlignmentStrategy.getNullStrategy()));
       } else if (!FormatterUtil.containsWhiteSpacesOnly(child) && child.getText().trim().length() > 0){
         result.add(createJavaBlock(child, mySettings, Indent.getSpaceIndent(1), null, AlignmentStrategy.getNullStrategy()));

java/java-impl/src/com/intellij/psi/impl/source/codeStyle/FormatCommentsProcessor.java

@@ -50,16 +50,30 @@ public class FormatCommentsProcessor implements PreFormatProcessor {
   @NotNull
   private static TextRange formatCommentsInner(@NotNull Project project, @NotNull ASTNode element, @NotNull final TextRange markedRange) {
     TextRange resultTextRange = markedRange;
+    final PsiElement elementPsi = element.getPsi();
     boolean shouldFormat = markedRange.contains(element.getTextRange());
 
     if (shouldFormat) {
-      TextRange before = element.getTextRange();
+      final ASTNode rangeAnchor;
+      // There are two possible cases:
+      //   1. Given element correspond to comment's owner (e.g. field or method);
+      //   2. Given element corresponds to comment itself;
+      // However, doc comment formatter replaces old comment with the new one, hence, old element becomes invalid. That's why we need
+      // to calculate text length delta not for the given comment element (it's invalid because removed from the AST tree) but for
+      // its parent.
+      if (elementPsi instanceof PsiDocComment) {
+        rangeAnchor = element.getTreeParent();
+      }
+      else {
+        rangeAnchor = element;
+      }
+      TextRange before = rangeAnchor.getTextRange();
       new CommentFormatter(project).processComment(element);
-      int deltaRange = element.getTextRange().getLength() - before.getLength();
+      int deltaRange = rangeAnchor.getTextRange().getLength() - before.getLength();
       resultTextRange = new TextRange(markedRange.getStartOffset(), markedRange.getEndOffset() + deltaRange);
     }
 
-    final PsiElement elementPsi = element.getPsi();
+    
     // If element is Psi{Method, Field, DocComment} and was formatted there is no reason to continue - we formatted all possible javadocs.
     // If element is out of range its children are also out of range. So in both cases formatting is finished. It's just for optimization.
     if ((shouldFormat && (elementPsi instanceof  PsiMethod || elementPsi instanceof PsiField || elementPsi instanceof PsiDocComment))
@@ -70,7 +84,7 @@ public class FormatCommentsProcessor implements PreFormatProcessor {
 
     ASTNode current = element.getFirstChildNode();
     while (current != null) {
-      //When element is PsiClass his PsiDocComment is formatted up to this moment, so we didn't need to format it again.
+      // When element is PsiClass its PsiDocComment is formatted up to this moment, so we didn't need to format it again.
       if (!(shouldFormat && current.getPsi() instanceof PsiDocComment && elementPsi instanceof PsiClass)) {
         resultTextRange = formatCommentsInner(project, current, resultTextRange);
       }

java/java-tests/testSrc/com/intellij/codeInsight/editorActions/FixDocCommentTest.groovy

@@ -34,7 +34,6 @@ class Test {
       expected: '''\
 class Test {
     /**
-     * <caret>
      * @param i
      * @return
      */