isValidPath is an older simple form of the validation performed by
checkValidPath. Use the latter as it more consistently matches
git-core's validation rules.

By running the same validation as fsck, callers creating an entry
for the DirCache are more likely to learn early they are trying
to build trees that will fail fsck.

Change-Id: Ibf5ac116097156aa05c18e231bc65c0854932eb1

Change-Id: I83ca25fb569c0dbc36eb374d5437fcf2b65a6f68

When there is a conflict sometimes we did not set the stage of
the conflict entries properly for the STAGE_1 entry.

Change-Id: I1c28ff6251fdbc95f7c40fc3e401f1b41157a9f6

Eclipse has some problem re-running single JUnit tests if
the tests are in Junit 3 format, but the JUnit 4 launcher
is used. This was quite unnecessary and the move was not
completed. We still have no JUnit4 test.

This completes the extermination of JUnit3. Most of the
work was global searce/replace using regular expression,
followed by numerous invocarions of quick-fix and organize
imports and verification that we had the same number of
tests before and after.

- Annotations were introduced.
- All references to JUnit3 classes removed
- Half-good replacement for getting the test name. This was
  needed to make the TestRngs work. The initialization of
  TestRngs was also made lazily since we can not longer find
  out the test name in runtime in the @Before methods.
- Renamed test classes to end with Test, with the exception
  of TestTranslateBundle, which fails from Maven
- Moved JGitTestUtil to the junit support bundle

Change-Id: Iddcd3da6ca927a7be773a9c63ebf8bb2147e2d13
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

A 0 file mode in a DirCacheEntry is not a valid mode.  To C git
such a value indicates the record should not be present.  We already
were catching this bad state and exceptioning out when writing tree
objects to disk, but we did not fail when writing the dircache back
to disk.  This allowed JGit applications to create a dircache file
which C git would not like to read.

Instead of checking the mode during writes, we now check during
mutation.  This allows application bugs to be detected sooner and
closer to the cause site.  It also allows us to avoid checking most
of the records which we read in from disk, as we can assume these
are formatted correctly.

Some of our unit tests were not setting the FileMode on their test
entry, so they had to be updated to use REGULAR_FILE.

Change-Id: Ie412053c390b737c0ece57b8e063e4355ee32437
Originally: http://thread.gmane.org/gmane.comp.version-control.git/128214/focus=128213
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CC: Adam W. Hawks <awhawks@writeme.com>

A dircache record must not use a path string like "/a" or "a//b"
as this results in a tree entry being written with a zero length
name component in the record.  C git does not support an empty name,
and neither does any modern filesystem.

A record also must not have a stage outside of the standard 0-3
value range, as there are only 2 bits of space available in the
on-disk format of the record to store the stage information.
Any other values would be truncated into this space, storing a
different value than the caller expected.

If an application tries to create a DirCache record with either of
these wrong values, we abort with an IllegalArgumentException.

Change-Id: I699de149efdfccd85d8adde07d3efd080e3b49c2
Originally: http://thread.gmane.org/gmane.comp.version-control.git/128214
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CC: Adam W. Hawks <awhawks@writeme.com>