IDEA-131342 Commenting XML line containing just - produces invalid XML

platform/lang-impl/src/com/intellij/codeInsight/generation/CommentByBlockCommentHandler.java

@@ -532,12 +532,11 @@ public class CommentByBlockCommentHandler extends MultiCaretCodeInsightActionHan
 
   static TextRange processDocument(Document document, RangeMarker marker, Commenter commenter, boolean escape) {
     if (commenter instanceof EscapingCommenter) {
-      TextRange range = TextRange.create(marker.getStartOffset(), marker.getEndOffset());
       if (escape) {
-        ((EscapingCommenter)commenter).escape(document, range);
+        ((EscapingCommenter)commenter).escape(document, marker);
       }
       else {
-        ((EscapingCommenter)commenter).unescape(document, range);
+        ((EscapingCommenter)commenter).unescape(document, marker);
       }
     }
     return TextRange.create(marker.getStartOffset(), marker.getEndOffset());

platform/lang-impl/src/com/intellij/codeInsight/generation/CommentByLineCommentHandler.java

@@ -600,6 +600,8 @@ public class CommentByLineCommentHandler extends MultiCaretCodeInsightActionHand
     String prefix = commenter.getLineCommentPrefix();
     int endOffset = document.getLineEndOffset(line);
     RangeMarker marker = document.createRangeMarker(offset, endOffset);
+    marker.setGreedyToLeft(true);
+    marker.setGreedyToRight(true);
     if (prefix != null) {
       if (commenter instanceof CommenterWithLineSuffix) {
         endOffset = CharArrayUtil.shiftBackward(document.getCharsSequence(), endOffset, " \t");

platform/lang-impl/src/com/intellij/codeInsight/generation/EscapingCommenter.java

@@ -17,14 +17,14 @@ package com.intellij.codeInsight.generation;
 
 import com.intellij.lang.Commenter;
 import com.intellij.openapi.editor.Document;
-import com.intellij.openapi.util.TextRange;
+import com.intellij.openapi.editor.RangeMarker;
 
 /**
  * @author Dmitry Avdeev
  */
 public interface EscapingCommenter extends Commenter {
 
-  void escape(Document document, TextRange range);
+  void escape(Document document, RangeMarker range);
 
-  void unescape(Document document, TextRange range);
+  void unescape(Document document, RangeMarker range);
 }

xml/impl/src/com/intellij/lang/xml/XmlCommenter.java

@@ -17,7 +17,7 @@ package com.intellij.lang.xml;
 
 import com.intellij.codeInsight.generation.EscapingCommenter;
 import com.intellij.openapi.editor.Document;
-import com.intellij.openapi.util.TextRange;
+import com.intellij.openapi.editor.RangeMarker;
 import com.intellij.util.text.CharArrayUtil;
 import org.jetbrains.annotations.NotNull;
 
@@ -59,7 +59,7 @@ public class XmlCommenter implements EscapingCommenter {
   }
 
   @Override
-  public void escape(Document document, TextRange range) {
+  public void escape(Document document, RangeMarker range) {
     String prefix = getBlockCommentPrefix();
     String suffix = getBlockCommentSuffix();
 
@@ -71,6 +71,8 @@ public class XmlCommenter implements EscapingCommenter {
     if (CharArrayUtil.regionMatches(document.getCharsSequence(), end - suffix.length(), suffix)) {
       end -= suffix.length();
     }
+    if (start >= end) return;
+
     for (int i = end - DOUBLE_DASH.length(); i >= start; i--) {
       if (CharArrayUtil.regionMatches(document.getCharsSequence(), i, DOUBLE_DASH) &&
           !CharArrayUtil.regionMatches(document.getCharsSequence(), i, suffix) &&
@@ -81,10 +83,16 @@ public class XmlCommenter implements EscapingCommenter {
     if (CharArrayUtil.regionMatches(document.getCharsSequence(), start, GT)) {
       document.replaceString(start, start + GT.length(), ESCAPED_GT);
     }
+    if (CharArrayUtil.regionMatches(document.getCharsSequence(), range.getStartOffset(), prefix + "-")) {
+      document.insertString(start, " ");
+    }
+    if (CharArrayUtil.regionMatches(document.getCharsSequence(), range.getEndOffset() - suffix.length() - 1, "-" + suffix)) {
+      document.insertString(range.getEndOffset() - suffix.length(), " ");
+    }
   }
 
   @Override
-  public void unescape(Document document, TextRange range) {
+  public void unescape(Document document, RangeMarker range) {
     final int start = range.getStartOffset();
     for (int i = range.getEndOffset(); i >= start; i--) {
       if (CharArrayUtil.regionMatches(document.getCharsSequence(), i, ESCAPED_DOUBLE_DASH)) {