[PATCH] merge-recursive: option to disable renames

["Felipe Gonçalves Assis" <felipeg.assis@gmail.com>]

The recursive strategy turns on rename detection by default. Add a
strategy option to disable rename detection even for exact renames.

Signed-off-by: Felipe Gonçalves Assis <felipegassis@gmail.com>
---

Hi, this is a patch relative to the "Custom merge driver with no rename
detection" thread, based on suggestions by Junio C Hamano.

 Documentation/merge-strategies.txt |  4 ++++
 merge-recursive.c                  | 16 +++++++++++++---
 merge-recursive.h                  |  1 +
 3 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/Documentation/merge-strategies.txt b/Documentation/merge-strategies.txt
index 7bbd19b..0528d85 100644
--- a/Documentation/merge-strategies.txt
+++ b/Documentation/merge-strategies.txt
@@ -81,6 +81,10 @@ no-renormalize;;
 	Disables the `renormalize` option.  This overrides the
 	`merge.renormalize` configuration variable.
 
+no-renames;;
+	Turn off rename detection.
+	See also linkgit:git-diff[1] `--no-renames`.
+
 rename-threshold=<n>;;
 	Controls the similarity threshold used for rename detection.
 	See also linkgit:git-diff[1] `-M`.
diff --git a/merge-recursive.c b/merge-recursive.c
index 8eabde2..ca67805 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -1839,9 +1839,16 @@ int merge_trees(struct merge_options *o,
 
 		entries = get_unmerged();
 		record_df_conflict_files(o, entries);
-		re_head  = get_renames(o, head, common, head, merge, entries);
-		re_merge = get_renames(o, merge, common, head, merge, entries);
-		clean = process_renames(o, re_head, re_merge);
+		if (o->detect_rename) {
+			re_head  = get_renames(o, head, common, head, merge, entries);
+			re_merge = get_renames(o, merge, common, head, merge, entries);
+			clean = process_renames(o, re_head, re_merge);
+		}
+		else {
+			re_head  = xcalloc(1, sizeof(struct string_list));
+			re_merge = xcalloc(1, sizeof(struct string_list));
+			clean = 1;
+		}
 		for (i = entries->nr-1; 0 <= i; i--) {
 			const char *path = entries->items[i].string;
 			struct stage_data *e = entries->items[i].util;
@@ -2039,6 +2046,7 @@ void init_merge_options(struct merge_options *o)
 	o->diff_rename_limit = -1;
 	o->merge_rename_limit = -1;
 	o->renormalize = 0;
+	o->detect_rename = DIFF_DETECT_RENAME;
 	merge_recursive_config(o);
 	if (getenv("GIT_MERGE_VERBOSITY"))
 		o->verbosity =
@@ -2088,6 +2096,8 @@ int parse_merge_opt(struct merge_options *o, const char *s)
 		o->renormalize = 1;
 	else if (!strcmp(s, "no-renormalize"))
 		o->renormalize = 0;
+	else if (!strcmp(s, "no-renames"))
+		o->detect_rename = 0;
 	else if (skip_prefix(s, "rename-threshold=", &arg)) {
 		if ((o->rename_score = parse_rename_score(&arg)) == -1 || *arg != 0)
 			return -1;
diff --git a/merge-recursive.h b/merge-recursive.h
index 9e090a3..52f0201 100644
--- a/merge-recursive.h
+++ b/merge-recursive.h
@@ -17,6 +17,7 @@ struct merge_options {
 	unsigned renormalize : 1;
 	long xdl_opts;
 	int verbosity;
+	int detect_rename;
 	int diff_rename_limit;
 	int merge_rename_limit;
 	int rename_score;
-- 
2.7.1.291.gd6478c6