[PATCH] revision.c: Clarify error message for missing objects

[Jakob Pfender <jpfender@elegosoft.com>]

[Sorry Junio, accidentally sent this to just you the first time around]

If "git show" is invoked on a hash for a file that doesn't exist, the
produced error message was "fatal: bad object <hash>". This is
misleading as the object isn't bad, but missing. As a matter of fact, if
an object is bad, this error message is never produced, because
parse_object() terminates with its own error message if the object is
corrupt.

This patch introduces a check to see whether an object exists (with the
appropriate error message if it doesn't) and removes the unnecessary and
misleading original error message if parse_object() fails.

Signed-off-by: Jakob Pfender <jpfender@elegosoft.com>
---
  revision.c |    4 ++--
  1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/revision.c b/revision.c
index 86d2470..085aac2 100644
--- a/revision.c
+++ b/revision.c
@@ -173,9 +173,9 @@ static struct object *get_reference(struct rev_info 
*revs, const char *name, con
  {
      struct object *object;

+    if (sha1_object_info(sha1, NULL) < 0)
+        die("Not a valid object name %s", name);
      object = parse_object(sha1);
-    if (!object)
-        die("bad object %s", name);
      object->flags |= flags;
      return object;
  }
-- 
1.7.0.4