IDEA-112387 Reformat code with rearrange entires on = fail on enum [CR-IC-2205]

java/java-tests/testSrc/com/intellij/psi/codeStyle/arrangement/JavaRearrangerBlankLinesTest.groovy

@@ -131,4 +131,16 @@ class Test {
 }'''
     doTest(initial: text, expected: text, rules: [rule(CLASS)] )
   }
+
+  void "test statements on the same line"() {
+    def before = '''\
+
+
+
+public enum Sender {a, b; private String value;
+}
+'''
+    doTest(initial: before, expected: before)
+  }
+
 }

platform/lang-impl/src/com/intellij/psi/codeStyle/arrangement/engine/ArrangementEngine.java

@@ -639,6 +639,10 @@ public class ArrangementEngine {
       }
     }
 
+    /**
+     * @return position <code>x</code> for which <code>myDocument.getText().substring(x, startOffset)</code> contains
+     * <code>blankLinesNumber</code> line feeds and <code>myDocument.getText.charAt(x-1) == '\n'</code>
+     */
     private int getBlankLineOffset(int blankLinesNumber, int startOffset) {
       int startLine = myDocument.getLineNumber(startOffset);
       if (startLine <= 0) {

platform/lang-impl/src/com/intellij/psi/codeStyle/arrangement/engine/ArrangementEntryWrapper.java

@@ -119,25 +119,17 @@ public class ArrangementEntryWrapper<E extends ArrangementEntry> {
 
   @SuppressWarnings("AssignmentToForLoopParameter")
   public void updateBlankLines(@NotNull Document document) {
-    int startLine = document.getLineNumber(getStartOffset());
     myBlankLinesBefore = 0;
-    if (startLine <= 0) {
-      return;
-    }
-    
+    int lineFeeds = 0;
     CharSequence text = document.getCharsSequence();
-    int lastLineFeed = document.getLineStartOffset(startLine) - 1;
-    for (int i = lastLineFeed - 1; i >= 0; i--) {
-      i = CharArrayUtil.shiftBackward(text, i, " \t");
-      if (text.charAt(i) == '\n') {
-        ++myBlankLinesBefore;
-      }
-      else {
-        break;
-      }
+    for (int current = getStartOffset() - 1; current >= 0; current--) {
+      current = CharArrayUtil.shiftBackward(text, current, " \t");
+      if (text.charAt(current) == '\n') lineFeeds++;
+      else break;
     }
+    if (lineFeeds > 0) myBlankLinesBefore = lineFeeds - 1;
   }
-  
+
   public void setNext(@Nullable ArrangementEntryWrapper<E> next) {
     myNext = next;
   }