[JGIT PATCH 00/14] TreeWalk D/F conflict detection

This series is about fixing the "mistake" in Git trees where
subtrees sort as through their name is "path/" and not "path".

Within a TreeWalk this is a problem because the tree contents:

    Tree 1     Tree 2
  ------------------------
    100644 a
               100644 a.c
               040000 a
    100644 b

needs to merge together both "a" paths from tree 1 and tree 2, but
these appear at different points in time when we merge-sort the two
trees together.

We use an infinite look-ahead and look-behind to identify these cases
and make the iteration look like this instead:

    Tree 1     Tree 2
  ------------------------
    100644 a   040000 a
               100644 a.c
    100644 b

which allows the application to handle the D/F conflict in a single
step, even though the contents of "a" may now be out-of-order within
the DirCache.  Fortunately DirCacheBuilder can automatically fix this
sort of ordering problem.


Shawn O. Pearce (14):
  Detect path names which overflow the name length field in the index
  Fix NB.decodeUInt16 to correctly handle the high byte
  Add test cases for NB.encode and NB.decode family of routines
  Fix DirCache's skip over null byte padding when reading a DIRC file
  Fix usage of assertEquals in DirCacheIteratorTest
  Refactor AbstractTreeIterator.pathCompare to force another mode
  Micro-optimize AbstractTreeIterator.pathCompare
  Optimize path comparsion within subtrees during TreeWalk
  Refactor AbstractTreeIterator semantics to start on first entry
  Make all AbstractTreeIterator implementations bi-directional
  Expose beginning of iterator indication from AbstractTreeIterator
  Allow application code to set ObjectIds in DirCacheEntry
  Create NameConflictTreeWalk to transparently detect D/F conflicts
  Add test case for NameConflictTreeWalk

 .../spearce/egit/core/ContainerTreeIterator.java   |    9 +-
 .../jgit/dircache/DirCacheBuilderIteratorTest.java |    2 +-
 .../jgit/dircache/DirCacheIteratorTest.java        |   28 +-
 .../jgit/treewalk/CanonicalTreeParserTest.java     |  261 ++++++++++++++++
 .../jgit/treewalk/NameConflictTreeWalkTest.java    |  205 ++++++++++++
 .../tst/org/spearce/jgit/util/NBTest.java          |  328 ++++++++++++++++++++
 .../src/org/spearce/jgit/dircache/DirCache.java    |    2 +-
 .../jgit/dircache/DirCacheBuildIterator.java       |    9 +-
 .../org/spearce/jgit/dircache/DirCacheEntry.java   |   41 +++-
 .../spearce/jgit/dircache/DirCacheIterator.java    |   84 +++--
 .../jgit/treewalk/AbstractTreeIterator.java        |  129 +++++---
 .../spearce/jgit/treewalk/CanonicalTreeParser.java |   94 +++++-
 .../spearce/jgit/treewalk/EmptyTreeIterator.java   |   12 +-
 .../spearce/jgit/treewalk/FileTreeIterator.java    |    5 +-
 .../jgit/treewalk/NameConflictTreeWalk.java        |  237 ++++++++++++++
 .../src/org/spearce/jgit/treewalk/TreeWalk.java    |   18 +-
 .../spearce/jgit/treewalk/WorkingTreeIterator.java |  132 ++++-----
 org.spearce.jgit/src/org/spearce/jgit/util/NB.java |   29 ++-
 18 files changed, 1418 insertions(+), 207 deletions(-)
 create mode 100644 org.spearce.jgit.test/tst/org/spearce/jgit/treewalk/CanonicalTreeParserTest.java
 create mode 100644 org.spearce.jgit.test/tst/org/spearce/jgit/treewalk/NameConflictTreeWalkTest.java
 create mode 100644 org.spearce.jgit.test/tst/org/spearce/jgit/util/NBTest.java
 create mode 100644 org.spearce.jgit/src/org/spearce/jgit/treewalk/NameConflictTreeWalk.java