--- a/src/org/tmatesoft/hg/internal/FileAnnotation.java	Fri Feb 22 20:21:24 2013 +0100
+++ b/src/org/tmatesoft/hg/internal/FileAnnotation.java	Sun Feb 24 00:11:40 2013 +0100
@@ -16,12 +16,18 @@
  */
 package org.tmatesoft.hg.internal;
 
-import java.util.LinkedList;
+import java.util.Formatter;
 
 import org.tmatesoft.hg.core.HgIterateDirection;
 import org.tmatesoft.hg.repo.HgBlameFacility;
+import org.tmatesoft.hg.repo.HgInvalidStateException;
+import org.tmatesoft.hg.repo.HgBlameFacility.AddBlock;
+import org.tmatesoft.hg.repo.HgBlameFacility.BlockData;
+import org.tmatesoft.hg.repo.HgBlameFacility.ChangeBlock;
+import org.tmatesoft.hg.repo.HgBlameFacility.DeleteBlock;
+import org.tmatesoft.hg.repo.HgBlameFacility.EqualBlock;
+import org.tmatesoft.hg.repo.HgBlameFacility.RevisionDescriptor;
 import org.tmatesoft.hg.repo.HgDataFile;
-import org.tmatesoft.hg.repo.HgBlameFacility.*;
 
 /**
  * Produce output like 'hg annotate' does
@@ -37,7 +43,7 @@
 		/**
 		 * Not necessarily invoked sequentially by line numbers
 		 */
-		void line(int lineNumber, int changesetRevIndex, LineDescriptor ld);
+		void line(int lineNumber, int changesetRevIndex, BlockData lineContent, LineDescriptor ld);
 	}
 
 	public interface LineDescriptor {
@@ -56,60 +62,168 @@
 		af.annotate(df, changelogRevisionIndex, fa, HgIterateDirection.NewToOld);
 	}
 
-	// blocks deleted in the target, as reported at the previous step
-	private LinkedList<DeleteBlock> deleted = new LinkedList<DeleteBlock>();
-	// blocks deleted in the origin, to become deletions in target at the next step
-	private LinkedList<DeleteBlock> newDeleted = new LinkedList<DeleteBlock>();
-	// keeps <startSeq1, startSeq2, len> of equal blocks, origin to target, from previous step
-	// XXX smth like IntSliceVector to access triples (or slices of any size, in fact)
-	// with easy indexing, e.g. #get(sliceIndex, indexWithinSlice)
-	// and vect.get(7,2) instead of vect.get(7*SIZEOF_SLICE+2)
-	private IntVector identical = new IntVector(20 * 3, 2 * 3);
+	// keeps <startSeq1, startSeq2, len> of equal blocks, origin to target, from some previous step
+	private RangeSeq activeEquals;
 	// equal blocks of the current iteration, to be recalculated before next step
 	// to track line number (current target to ultimate target) mapping 
-	private IntVector newIdentical = new IntVector(20 * 3, 2 * 3);
+	private RangeSeq intermediateEquals = new RangeSeq();
 
 	private boolean[] knownLines;
 	private final LineInspector delegate;
+	private RevisionDescriptor revisionDescriptor;
+	private BlockData lineContent;
+
+	private IntMap<RangeSeq> mergedRanges = new IntMap<RangeSeq>(10);
+	private IntMap<RangeSeq> equalRanges = new IntMap<RangeSeq>(10);
+	private boolean activeEqualsComesFromMerge = false;
 
 	public FileAnnotation(LineInspector lineInspector) {
 		delegate = lineInspector;
 	}
 
 	public void start(RevisionDescriptor rd) {
+		revisionDescriptor = rd;
 		if (knownLines == null) {
-			knownLines = new boolean[rd.target().elementCount()];
+			lineContent = rd.target();
+			knownLines = new boolean[lineContent.elementCount()];
+			activeEquals = new RangeSeq();
+			activeEquals.add(0, 0, knownLines.length);
+			equalRanges.put(rd.targetChangesetIndex(), activeEquals);
+		} else {
+			activeEquals = equalRanges.get(rd.targetChangesetIndex());
+			if (activeEquals == null) {
+				// we didn't see this target revision as origin yet
+				// the only way this may happen is that this revision was a merge parent
+				activeEquals = mergedRanges.get(rd.targetChangesetIndex());
+				activeEqualsComesFromMerge = true;
+				if (activeEquals == null) {
+					throw new HgInvalidStateException(String.format("Can't find previously visited revision %d (while in %d->%1$d diff)", rd.targetChangesetIndex(), rd.originChangesetIndex()));
+				}
+			}
 		}
 	}
 
-	//		private static void ppp(IntVector v) {
-	//			for (int i = 0; i < v.size(); i+= 3) {
-	//				int len = v.get(i+2);
-	//				System.out.printf("[%d..%d) == [%d..%d);  ", v.get(i), v.get(i) + len, v.get(i+1), v.get(i+1) + len);
-	//			}
-	//			System.out.println();
-	//		}
+	public void done(RevisionDescriptor rd) {
+		// update line numbers of the intermediate target to point to ultimate target's line numbers
+		RangeSeq v = intermediateEquals.intersect(activeEquals);
+		if (activeEqualsComesFromMerge) {
+			mergedRanges.put(rd.originChangesetIndex(), v);
+		} else {
+			equalRanges.put(rd.originChangesetIndex(), v);
+		}
+		intermediateEquals.clear();
+		activeEquals = null;
+		activeEqualsComesFromMerge = false;
+		revisionDescriptor = null;
+	}
 
-	public void done(RevisionDescriptor rd) {
-		if (identical.size() > 0) {
-			// update line numbers of the intermediate target to point to ultimate target's line numbers
-			IntVector v = new IntVector(identical.size(), 2 * 3);
-			for (int i = 0; i < newIdentical.size(); i += 3) {
-				int originLine = newIdentical.get(i);
-				int targetLine = newIdentical.get(i + 1);
-				int length = newIdentical.get(i + 2);
+	public void same(EqualBlock block) {
+		intermediateEquals.add(block.originStart(), block.targetStart(), block.length());
+	}
+
+	public void added(AddBlock block) {
+		RangeSeq rs = null;
+		if (revisionDescriptor.isMerge() && block.originChangesetIndex() == revisionDescriptor.mergeChangesetIndex()) {
+			rs = mergedRanges.get(revisionDescriptor.mergeChangesetIndex());
+			if (rs == null) {
+				mergedRanges.put(revisionDescriptor.mergeChangesetIndex(), rs = new RangeSeq());
+			}
+		}
+		if (activeEquals.size() == 0) {
+			return;
+		}
+		for (int i = 0, ln = block.firstAddedLine(), x = block.totalAddedLines(); i < x; i++, ln++) {
+			int lnInFinal = activeEquals.mapLineIndex(ln);
+			if (lnInFinal != -1/* && !knownLines[lnInFinal]*/) {
+				if (rs != null) {
+					rs.add(block.insertedAt() + i, lnInFinal, 1);
+				} else {
+					delegate.line(lnInFinal, block.targetChangesetIndex(), lineContent.elementAt(lnInFinal), new LineDescriptorImpl());
+				}
+				knownLines[lnInFinal] = true;
+			}
+		}
+	}
+
+	public void changed(ChangeBlock block) {
+		added(block);
+	}
+
+	public void deleted(DeleteBlock block) {
+	}
+
+	private final class LineDescriptorImpl implements LineDescriptor {
+		LineDescriptorImpl() {
+		}
+
+		public int totalLines() {
+			return FileAnnotation.this.knownLines.length;
+		}
+	}
+
+	private static class RangeSeq {
+		// XXX smth like IntSliceVector to access triples (or slices of any size, in fact)
+		// with easy indexing, e.g. #get(sliceIndex, indexWithinSlice)
+		// and vect.get(7,2) instead of vect.get(7*SIZEOF_SLICE+2)
+		private final IntVector ranges = new IntVector(3*10, 3*5);
+		private int count;
+		
+		public void add(int start1, int start2, int length) {
+			if (count > 0) {
+				int lastIndex = 3 * (count-1);
+				int lastS1 = ranges.get(lastIndex);
+				int lastS2 = ranges.get(lastIndex + 1);
+				int lastLen = ranges.get(lastIndex + 2);
+				if (start1 == lastS1 + lastLen && start2 == lastS2 + lastLen) {
+					// new range continues the previous one - just increase the length
+					ranges.set(lastIndex + 2, lastLen + length);
+					return;
+				}
+			}
+			ranges.add(start1, start2, length);
+			count++;
+		}
+		
+		public void clear() {
+			ranges.clear();
+			count = 0;
+		}
+
+		public int size() {
+			return count;
+		}
+
+		public int mapLineIndex(int ln) {
+			for (int i = 0; i < ranges.size(); i += 3) {
+				int s1 = ranges.get(i);
+				if (s1 > ln) {
+					return -1;
+				}
+				int l = ranges.get(i+2);
+				if (s1 + l > ln) {
+					int s2 = ranges.get(i + 1);
+					return s2 + (ln - s1);
+				}
+			}
+			return -1;
+		}
+		
+		public RangeSeq intersect(RangeSeq target) {
+			RangeSeq v = new RangeSeq();
+			for (int i = 0; i < ranges.size(); i += 3) {
+				int originLine = ranges.get(i);
+				int targetLine = ranges.get(i + 1);
+				int length = ranges.get(i + 2);
 				int startTargetLine = -1, startOriginLine = -1, c = 0;
 				for (int j = 0; j < length; j++) {
-					int lnInFinal = mapLineIndex(targetLine + j);
+					int lnInFinal = target.mapLineIndex(targetLine + j);
 					if (lnInFinal == -1 || (startTargetLine != -1 && lnInFinal != startTargetLine + c)) {
 						// the line is not among "same" in ultimate origin
 						// or belongs to another/next "same" chunk 
 						if (startOriginLine == -1) {
 							continue;
 						}
-						v.add(startOriginLine);
-						v.add(startTargetLine);
-						v.add(c);
+						v.add(startOriginLine, startTargetLine, c);
 						c = 0;
 						startOriginLine = startTargetLine = -1;
 						// fall-through to check if it's not complete miss but a next chunk
@@ -120,6 +234,7 @@
 							startTargetLine = lnInFinal;
 							c = 1;
 						} else {
+							// lnInFinal != startTargetLine + s is covered above
 							assert lnInFinal == startTargetLine + c;
 							c++;
 						}
@@ -127,94 +242,28 @@
 				}
 				if (startOriginLine != -1) {
 					assert c > 0;
-					v.add(startOriginLine);
-					v.add(startTargetLine);
-					v.add(c);
+					v.add(startOriginLine, startTargetLine, c);
 				}
 			}
-			newIdentical.clear();
-			identical = v;
-		} else {
-			IntVector li = newIdentical;
-			newIdentical = identical;
-			identical = li;
-		}
-		LinkedList<DeleteBlock> ld = newDeleted;
-		deleted.clear();
-		newDeleted = deleted;
-		deleted = ld;
-	}
-
-	public void same(EqualBlock block) {
-		newIdentical.add(block.originStart());
-		newIdentical.add(block.targetStart());
-		newIdentical.add(block.length());
-	}
-
-	public void added(AddBlock block) {
-		for (int i = 0, ln = block.firstAddedLine(), x = block.totalAddedLines(); i < x; i++, ln++) {
-			int lnInFinal = mapLineIndex(ln);
-			if (lnInFinal != -1 && !knownLines[lnInFinal]) {
-				delegate.line(lnInFinal, block.targetChangesetIndex(), new LineDescriptorImpl());
-				knownLines[lnInFinal] = true;
-			}
+			return v;
 		}
-	}
-
-	public void changed(ChangeBlock block) {
-		deleted(block);
-		added(block);
-	}
-
-	public void deleted(DeleteBlock block) {
-		newDeleted.add(block);
-	}
-
-	// line - index in the target
-	private boolean isDeleted(int line) {
-		for (DeleteBlock b : deleted) {
-			if (b.firstRemovedLine() > line) {
-				break;
+		
+		@SuppressWarnings("unused")
+		public CharSequence dump() {
+			StringBuilder sb = new StringBuilder();
+			Formatter f = new Formatter(sb);
+			for (int i = 0; i < ranges.size(); i += 3) {
+				int s1 = ranges.get(i);
+				int s2 = ranges.get(i + 1);
+				int len = ranges.get(i + 2);
+				f.format("[%d..%d) == [%d..%d);  ", s1, s1 + len, s2, s2 + len);
 			}
-			// line >= b.firstRemovedLine
-			if (b.firstRemovedLine() + b.totalRemovedLines() > line) {
-				return true;
-			}
+			return sb;
 		}
-		return false;
-	}
-
-	// map target lines to the lines of the revision being annotated (the one that came first)
-	private int mapLineIndex(int ln) {
-		if (isDeleted(ln)) {
-			return -1;
-		}
-		if (identical.isEmpty()) {
-			return ln;
-		}
-		for (int i = 0; i < identical.size(); i += 3) {
-			final int originStart = identical.get(i);
-			if (originStart > ln) {
-				//					assert false;
-				return -1;
-			}
-			// ln >= b.originStart
-			final int length = identical.get(i + 2);
-			if (originStart + length > ln) {
-				int targetStart = identical.get(i + 1);
-				return targetStart + (ln - originStart);
-			}
-		}
-		//			assert false;
-		return -1;
-	}
-
-	private final class LineDescriptorImpl implements LineDescriptor {
-		LineDescriptorImpl() {
-		}
-
-		public int totalLines() {
-			return FileAnnotation.this.knownLines.length;
+		
+		@Override
+		public String toString() {
+			return String.format("RangeSeq[%d]:%s", count, dump());
 		}
 	}
 }
\ No newline at end of file