[PATCH] read-cache.c: Ensure unmerged entries are removed

[Jaime Soriano Pastor <jsorianopastor@gmail.com>]

Wrong implementations of tools that modify the index can left
some files as merged and unmerged at the same time. Avoid undesiderable
behaviours by handling this situation.

Signed-off-by: Jaime Soriano Pastor <jsorianopastor@gmail.com>
---
 read-cache.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/read-cache.c b/read-cache.c
index 7f5645e..23e46e1 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -935,6 +935,7 @@ static int add_index_entry_with_check(struct index_state *istate, struct cache_e
 	int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
 	int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
 	int new_only = option & ADD_CACHE_NEW_ONLY;
+	int replaced = 0;
 
 	cache_tree_invalidate_path(istate->cache_tree, ce->name);
 	pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce));
@@ -943,9 +944,10 @@ static int add_index_entry_with_check(struct index_state *istate, struct cache_e
 	if (pos >= 0) {
 		if (!new_only)
 			replace_index_entry(istate, pos, ce);
-		return 0;
-	}
-	pos = -pos-1;
+		pos++;
+		replaced = 1;
+	} else
+		pos = -pos-1;
 
 	/*
 	 * Inserting a merged entry ("stage 0") into the index
@@ -959,6 +961,8 @@ static int add_index_entry_with_check(struct index_state *istate, struct cache_e
 		}
 	}
 
+	if (replaced)
+		return 0;
 	if (!ok_to_add)
 		return -1;
 	if (!verify_path(ce->name))
-- 
2.0.4.1.g8a38f21.dirty