Fix rename detection to use actual blob size

The size data in the index may not reflect the actual size of the
blob data from the ODB when content filtering comes into play.
This commit fixes rename detection to use the actual blob size when
calculating data signatures instead of the value from the index.

Because of a misunderstanding on my part, I first converted the
git_index_add_bypath API to use the post-filtered blob data size
in creating the index entry.  I backed that change out, but I
kept the overall refactoring of that routine and the new internal
git_blob__create_from_paths API because it eliminates an extra
stat() call from the code that adds a file to the index.

The existing tests actually cover this code path, at least when
running on Windows, so at this point I'm not adding new tests to
cover the changes.

1 files changed, 8 insertions, 26 deletions

diff --git a/src/index.c b/src/index.c
index 0610eb5b9..cbdd43bdc 100644
--- a/src/index.c
+++ b/src/index.c
@@ -16,6 +16,7 @@
 #include "iterator.h"
 #include "pathspec.h"
 #include "ignore.h"
+#include "blob.h"
 
 #include "git2/odb.h"
 #include "git2/oid.h"
@@ -604,42 +605,23 @@ int git_index_entry__cmp_icase(const void *a, const void *b)
 	return strcasecmp(entry_a->path, entry_b->path);
 }
 
-static int index_entry_init(git_index_entry **entry_out, git_index *index, const char *rel_path)
+static int index_entry_init(
+	git_index_entry **entry_out, git_index *index, const char *rel_path)
 {
+	int error = 0;
 	git_index_entry *entry = NULL;
 	struct stat st;
 	git_oid oid;
-	const char *workdir;
-	git_buf full_path = GIT_BUF_INIT;
-	int error;
 
 	if (INDEX_OWNER(index) == NULL)
 		return create_index_error(-1,
 			"Could not initialize index entry. "
 			"Index is not backed up by an existing repository.");
 
-	workdir = git_repository_workdir(INDEX_OWNER(index));
-
-	if (!workdir)
-		return create_index_error(GIT_EBAREREPO,
-			"Could not initialize index entry. Repository is bare");
-
-	if ((error = git_buf_joinpath(&full_path, workdir, rel_path)) < 0)
-		return error;
-
-	if ((error = git_path_lstat(full_path.ptr, &st)) < 0) {
-		git_buf_free(&full_path);
-		return error;
-	}
-
-	git_buf_free(&full_path); /* done with full path */
-
-	/* There is no need to validate the rel_path here, since it will be
-	 * immediately validated by the call to git_blob_create_fromfile.
-	 */
-
-	/* write the blob to disk and get the oid */
-	if ((error = git_blob_create_fromworkdir(&oid, INDEX_OWNER(index), rel_path)) < 0)
+	/* write the blob to disk and get the oid and stat info */
+	error = git_blob__create_from_paths(
+		&oid, &st, INDEX_OWNER(index), NULL, rel_path, 0, true);
+	if (error < 0)
 		return error;
 
 	entry = git__calloc(1, sizeof(git_index_entry));