X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=unpack-trees.c;h=e5749ef638b4a9a490894d9d4fc5876d904ab9ac;hb=1a9016aae5aa8c468bb2d8d5dd16303d5c005869;hp=1ab28fda45be940b300b504ae029f3fba2c28fa9;hpb=eafa29b7cb27fa0e14d9629e66d6866292620113;p=git.git

diff --git a/unpack-trees.c b/unpack-trees.c
index 1ab28fda4..e5749ef63 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -8,6 +8,36 @@
 #include "progress.h"
 #include "refs.h"
 
+/*
+ * Error messages expected by scripts out of plumbing commands such as
+ * read-tree.  Non-scripted Porcelain is not required to use these messages
+ * and in fact are encouraged to reword them to better suit their particular
+ * situation better.  See how "git checkout" replaces not_uptodate_file to
+ * explain why it does not allow switching between branches when you have
+ * local changes, for example.
+ */
+static struct unpack_trees_error_msgs unpack_plumbing_errors = {
+	/* would_overwrite */
+	"Entry '%s' would be overwritten by merge. Cannot merge.",
+
+	/* not_uptodate_file */
+	"Entry '%s' not uptodate. Cannot merge.",
+
+	/* not_uptodate_dir */
+	"Updating '%s' would lose untracked files in it",
+
+	/* would_lose_untracked */
+	"Untracked working tree file '%s' would be %s by merge.",
+
+	/* bind_overlap */
+	"Entry '%s' overlaps with '%s'.  Cannot bind.",
+};
+
+#define ERRORMSG(o,fld) \
+	( ((o) && (o)->msgs.fld) \
+	? ((o)->msgs.fld) \
+	: (unpack_plumbing_errors.fld) )
+
 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
 	unsigned int set, unsigned int clear)
 {
@@ -328,8 +358,13 @@ static int unpack_failed(struct unpack_trees_options *o, const char *message)
 	return -1;
 }
 
+/*
+ * N-way merge "len" trees.  Returns 0 on success, -1 on failure to manipulate the
+ * resulting index, -2 on failure to reflect the changes to the work tree.
+ */
 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
 {
+	int ret;
 	static struct cache_entry *dfc;
 
 	if (len > MAX_UNPACK_TREES)
@@ -341,12 +376,13 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
 	state.refresh_cache = 1;
 
 	memset(&o->result, 0, sizeof(o->result));
+	o->result.initialized = 1;
 	if (o->src_index)
 		o->result.timestamp = o->src_index->timestamp;
 	o->merge_size = len;
 
 	if (!dfc)
-		dfc = xcalloc(1, sizeof(struct cache_entry) + 1);
+		dfc = xcalloc(1, cache_entry_size(0));
 	o->df_conflict_entry = dfc;
 
 	if (len) {
@@ -374,19 +410,17 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
 		return unpack_failed(o, "Merge requires file-level merging");
 
 	o->src_index = NULL;
-	if (check_updates(o))
-		return -1;
+	ret = check_updates(o) ? (-2) : 0;
 	if (o->dst_index)
 		*o->dst_index = o->result;
-	return 0;
+	return ret;
 }
 
 /* Here come the merge functions */
 
-static int reject_merge(struct cache_entry *ce)
+static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
 {
-	return error("Entry '%s' would be overwritten by merge. Cannot merge.",
-		     ce->name);
+	return error(ERRORMSG(o, would_overwrite), ce->name);
 }
 
 static int same(struct cache_entry *a, struct cache_entry *b)
@@ -430,7 +464,7 @@ static int verify_uptodate(struct cache_entry *ce,
 	if (errno == ENOENT)
 		return 0;
 	return o->gently ? -1 :
-		error("Entry '%s' not uptodate. Cannot merge.", ce->name);
+		error(ERRORMSG(o, not_uptodate_file), ce->name);
 }
 
 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
@@ -517,8 +551,7 @@ static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
 	i = read_directory(&d, ce->name, pathbuf, namelen+1, NULL);
 	if (i)
 		return o->gently ? -1 :
-			error("Updating '%s' would lose untracked files in it",
-			      ce->name);
+			error(ERRORMSG(o, not_uptodate_dir), ce->name);
 	free(pathbuf);
 	return cnt;
 }
@@ -618,8 +651,7 @@ static int verify_absent(struct cache_entry *ce, const char *action,
 		}
 
 		return o->gently ? -1 :
-			error("Untracked working tree file '%s' "
-			      "would be %s by merge.", ce->name, action);
+			error(ERRORMSG(o, would_lose_untracked), ce->name, action);
 	}
 	return 0;
 }
@@ -751,7 +783,7 @@ int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
 	/* #14, #14ALT, #2ALT */
 	if (remote && !df_conflict_head && head_match && !remote_match) {
 		if (index && !same(index, remote) && !same(index, head))
-			return o->gently ? -1 : reject_merge(index);
+			return o->gently ? -1 : reject_merge(index, o);
 		return merged_entry(remote, index, o);
 	}
 	/*
@@ -759,7 +791,7 @@ int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
 	 * make sure that it matches head.
 	 */
 	if (index && !same(index, head))
-		return o->gently ? -1 : reject_merge(index);
+		return o->gently ? -1 : reject_merge(index, o);
 
 	if (head) {
 		/* #5ALT, #15 */
@@ -901,16 +933,25 @@ int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
 		else {
 			/* all other failures */
 			if (oldtree)
-				return o->gently ? -1 : reject_merge(oldtree);
+				return o->gently ? -1 : reject_merge(oldtree, o);
 			if (current)
-				return o->gently ? -1 : reject_merge(current);
+				return o->gently ? -1 : reject_merge(current, o);
 			if (newtree)
-				return o->gently ? -1 : reject_merge(newtree);
+				return o->gently ? -1 : reject_merge(newtree, o);
 			return -1;
 		}
 	}
-	else if (newtree)
+	else if (newtree) {
+		if (oldtree && !o->initial_checkout) {
+			/*
+			 * deletion of the path was staged;
+			 */
+			if (same(oldtree, newtree))
+				return 1;
+			return reject_merge(oldtree, o);
+		}
 		return merged_entry(newtree, current, o);
+	}
 	return deleted_entry(oldtree, current, o);
 }
 
@@ -931,7 +972,7 @@ int bind_merge(struct cache_entry **src,
 			     o->merge_size);
 	if (a && old)
 		return o->gently ? -1 :
-			error("Entry '%s' overlaps with '%s'.  Cannot bind.", a->name, old->name);
+			error(ERRORMSG(o, bind_overlap), a->name, old->name);
 	if (!a)
 		return keep_entry(old, o);
 	else