From 8cc5b29065e19267cbc08b39c34674b02c2e3d59 Mon Sep 17 00:00:00 2001
From: Avery Pennarun <apenwarr@gmail.com>
Date: Wed, 25 Nov 2009 21:23:55 -0500
Subject: git merge -X<option>

Teach "-X <option>" command line argument to "git merge" that is passed to
strategy implementations.  "ours" and "theirs" autoresolution introduced
by the previous commit can be asked to the recursive strategy.

Signed-off-by: Avery Pennarun <apenwarr@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin-merge-recursive.c b/builtin-merge-recursive.c
index 710674c..1a160d8 100644
--- a/builtin-merge-recursive.c
+++ b/builtin-merge-recursive.c
@@ -26,18 +26,29 @@ int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
 
 	init_merge_options(&o);
 	if (argv[0]) {
-		int namelen = strlen(argv[0]);
-		if (8 < namelen &&
-		    !strcmp(argv[0] + namelen - 8, "-subtree"))
-			o.subtree_merge = 1;
+		if (!suffixcmp(argv[0], "-subtree"))
+			o.recursive_variant = MERGE_RECURSIVE_SUBTREE;
 	}
 
 	if (argc < 4)
 		usagef("%s <base>... -- <head> <remote> ...", argv[0]);
 
 	for (i = 1; i < argc; ++i) {
-		if (!strcmp(argv[i], "--"))
-			break;
+		const char *arg = argv[i];
+
+		if (!prefixcmp(arg, "--")) {
+			if (!arg[2])
+				break;
+			if (!strcmp(arg+2, "ours"))
+				o.recursive_variant = MERGE_RECURSIVE_OURS;
+			else if (!strcmp(arg+2, "theirs"))
+				o.recursive_variant = MERGE_RECURSIVE_THEIRS;
+			else if (!strcmp(arg+2, "subtree"))
+				o.recursive_variant = MERGE_RECURSIVE_SUBTREE;
+			else
+				die("Unknown option %s", arg);
+			continue;
+		}
 		if (bases_count < ARRAY_SIZE(bases)-1) {
 			unsigned char *sha = xmalloc(20);
 			if (get_sha1(argv[i], sha))
diff --git a/builtin-merge.c b/builtin-merge.c
index 855cf65..42f19e1 100644
--- a/builtin-merge.c
+++ b/builtin-merge.c
@@ -50,6 +50,8 @@ static struct commit_list *remoteheads;
 static unsigned char head[20], stash[20];
 static struct strategy **use_strategies;
 static size_t use_strategies_nr, use_strategies_alloc;
+static const char **xopts;
+static size_t xopts_nr, xopts_alloc;
 static const char *branch;
 static int verbosity;
 
@@ -146,6 +148,17 @@ static int option_parse_strategy(const struct option *opt,
 	return 0;
 }
 
+static int option_parse_x(const struct option *opt,
+			  const char *arg, int unset)
+{
+	if (unset)
+		return 0;
+
+	ALLOC_GROW(xopts, xopts_nr + 1, xopts_alloc);
+	xopts[xopts_nr++] = xstrdup(arg);
+	return 0;
+}
+
 static int option_parse_n(const struct option *opt,
 			  const char *arg, int unset)
 {
@@ -172,6 +185,8 @@ static struct option builtin_merge_options[] = {
 		"abort if fast-forward is not possible"),
 	OPT_CALLBACK('s', "strategy", &use_strategies, "strategy",
 		"merge strategy to use", option_parse_strategy),
+	OPT_CALLBACK('X', "strategy-option", &xopts, "option=value",
+		"option for selected merge strategy", option_parse_x),
 	OPT_CALLBACK('m', "message", &merge_msg, "message",
 		"message to be used for the merge commit (if any)",
 		option_parse_message),
@@ -534,7 +549,7 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
 			      const char *head_arg)
 {
 	const char **args;
-	int i = 0, ret;
+	int i = 0, x = 0, ret;
 	struct commit_list *j;
 	struct strbuf buf = STRBUF_INIT;
 	int index_fd;
@@ -563,7 +578,18 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
 
 		init_merge_options(&o);
 		if (!strcmp(strategy, "subtree"))
-			o.subtree_merge = 1;
+			o.recursive_variant = MERGE_RECURSIVE_SUBTREE;
+
+		for (x = 0; x < xopts_nr; x++) {
+			if (!strcmp(xopts[x], "ours"))
+				o.recursive_variant = MERGE_RECURSIVE_OURS;
+			else if (!strcmp(xopts[x], "theirs"))
+				o.recursive_variant = MERGE_RECURSIVE_THEIRS;
+			else if (!strcmp(xopts[x], "subtree"))
+				o.recursive_variant = MERGE_RECURSIVE_SUBTREE;
+			else
+				die("Unknown option for merge-recursive: -X%s", xopts[x]);
+		}
 
 		o.branch1 = head_arg;
 		o.branch2 = remoteheads->item->util;
@@ -581,10 +607,16 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
 		rollback_lock_file(lock);
 		return clean ? 0 : 1;
 	} else {
-		args = xmalloc((4 + commit_list_count(common) +
+		args = xmalloc((4 + xopts_nr + commit_list_count(common) +
 					commit_list_count(remoteheads)) * sizeof(char *));
 		strbuf_addf(&buf, "merge-%s", strategy);
 		args[i++] = buf.buf;
+		for (x = 0; x < xopts_nr; x++) {
+			char *s = xmalloc(strlen(xopts[x])+2+1);
+			strcpy(s, "--");
+			strcpy(s+2, xopts[x]);
+			args[i++] = s;
+		}
 		for (j = common; j; j = j->next)
 			args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
 		args[i++] = "--";
@@ -595,6 +627,8 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
 		ret = run_command_v_opt(args, RUN_GIT_CMD);
 		strbuf_release(&buf);
 		i = 1;
+		for (x = 0; x < xopts_nr; x++)
+			free((void *)args[i++]);
 		for (j = common; j; j = j->next)
 			free((void *)args[i++]);
 		i += 2;
diff --git a/contrib/examples/git-merge.sh b/contrib/examples/git-merge.sh
index 500635f..8f617fc 100755
--- a/contrib/examples/git-merge.sh
+++ b/contrib/examples/git-merge.sh
@@ -31,10 +31,11 @@ LF='
 '
 
 all_strategies='recur recursive octopus resolve stupid ours subtree'
+all_strategies="$all_strategies recursive-ours recursive-theirs"
 default_twohead_strategies='recursive'
 default_octopus_strategies='octopus'
 no_fast_forward_strategies='subtree ours'
-no_trivial_strategies='recursive recur subtree ours'
+no_trivial_strategies='recursive recur subtree ours recursive-ours recursive-theirs'
 use_strategies=
 
 allow_fast_forward=t
diff --git a/git-compat-util.h b/git-compat-util.h
index 5c59687..f64cc45 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -198,6 +198,7 @@ extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)))
 extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 
 extern int prefixcmp(const char *str, const char *prefix);
+extern int suffixcmp(const char *str, const char *suffix);
 extern time_t tm_to_time_t(const struct tm *tm);
 
 static inline const char *skip_prefix(const char *str, const char *prefix)
diff --git a/git.c b/git.c
index 11544cd..4735f11 100644
--- a/git.c
+++ b/git.c
@@ -332,6 +332,8 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "merge-file", cmd_merge_file },
 		{ "merge-ours", cmd_merge_ours, RUN_SETUP },
 		{ "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
+		{ "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
+		{ "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 		{ "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 		{ "mktree", cmd_mktree, RUN_SETUP },
 		{ "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
diff --git a/ll-merge.c b/ll-merge.c
index 2d6b6d6..45f7e01 100644
--- a/ll-merge.c
+++ b/ll-merge.c
@@ -18,7 +18,7 @@ typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
 			   mmfile_t *orig,
 			   mmfile_t *src1, const char *name1,
 			   mmfile_t *src2, const char *name2,
-			   int virtual_ancestor);
+			   int flag);
 
 struct ll_merge_driver {
 	const char *name;
@@ -38,14 +38,14 @@ static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
 			   mmfile_t *orig,
 			   mmfile_t *src1, const char *name1,
 			   mmfile_t *src2, const char *name2,
-			   int virtual_ancestor)
+			   int flag)
 {
 	/*
 	 * The tentative merge result is "ours" for the final round,
 	 * or common ancestor for an internal merge.  Still return
 	 * "conflicted merge" status.
 	 */
-	mmfile_t *stolen = virtual_ancestor ? orig : src1;
+	mmfile_t *stolen = (flag & 01) ? orig : src1;
 
 	result->ptr = stolen->ptr;
 	result->size = stolen->size;
@@ -59,10 +59,11 @@ static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
 			mmfile_t *orig,
 			mmfile_t *src1, const char *name1,
 			mmfile_t *src2, const char *name2,
-			int virtual_ancestor)
+			int flag)
 {
 	xpparam_t xpp;
 	int style = 0;
+	int favor = (flag >> 1) & 03;
 
 	if (buffer_is_binary(orig->ptr, orig->size) ||
 	    buffer_is_binary(src1->ptr, src1->size) ||
@@ -72,8 +73,7 @@ static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
 		return ll_binary_merge(drv_unused, result,
 				       path,
 				       orig, src1, name1,
-				       src2, name2,
-				       virtual_ancestor);
+				       src2, name2, flag);
 	}
 
 	memset(&xpp, 0, sizeof(xpp));
@@ -82,7 +82,7 @@ static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
 	return xdl_merge(orig,
 			 src1, name1,
 			 src2, name2,
-			 &xpp, XDL_MERGE_ZEALOUS | style,
+			 &xpp, XDL_MERGE_FLAGS(XDL_MERGE_ZEALOUS, style, favor),
 			 result);
 }
 
@@ -92,7 +92,7 @@ static int ll_union_merge(const struct ll_merge_driver *drv_unused,
 			  mmfile_t *orig,
 			  mmfile_t *src1, const char *name1,
 			  mmfile_t *src2, const char *name2,
-			  int virtual_ancestor)
+			  int flag)
 {
 	char *src, *dst;
 	long size;
@@ -104,7 +104,7 @@ static int ll_union_merge(const struct ll_merge_driver *drv_unused,
 	git_xmerge_style = 0;
 	status = ll_xdl_merge(drv_unused, result, path_unused,
 			      orig, src1, NULL, src2, NULL,
-			      virtual_ancestor);
+			      flag);
 	git_xmerge_style = saved_style;
 	if (status <= 0)
 		return status;
@@ -165,7 +165,7 @@ static int ll_ext_merge(const struct ll_merge_driver *fn,
 			mmfile_t *orig,
 			mmfile_t *src1, const char *name1,
 			mmfile_t *src2, const char *name2,
-			int virtual_ancestor)
+			int flag)
 {
 	char temp[3][50];
 	struct strbuf cmd = STRBUF_INIT;
@@ -356,10 +356,11 @@ int ll_merge(mmbuffer_t *result_buf,
 	     mmfile_t *ancestor,
 	     mmfile_t *ours, const char *our_label,
 	     mmfile_t *theirs, const char *their_label,
-	     int virtual_ancestor)
+	     int flag)
 {
 	const char *ll_driver_name;
 	const struct ll_merge_driver *driver;
+	int virtual_ancestor = flag & 01;
 
 	ll_driver_name = git_path_check_merge(path);
 	driver = find_ll_merge_driver(ll_driver_name);
@@ -369,5 +370,5 @@ int ll_merge(mmbuffer_t *result_buf,
 	return driver->fn(driver, result_buf, path,
 			  ancestor,
 			  ours, our_label,
-			  theirs, their_label, virtual_ancestor);
+			  theirs, their_label, flag);
 }
diff --git a/ll-merge.h b/ll-merge.h
index 5388422..aaed46d 100644
--- a/ll-merge.h
+++ b/ll-merge.h
@@ -10,6 +10,6 @@ int ll_merge(mmbuffer_t *result_buf,
 	     mmfile_t *ancestor,
 	     mmfile_t *ours, const char *our_label,
 	     mmfile_t *theirs, const char *their_label,
-	     int virtual_ancestor);
+	     int flag);
 
 #endif
diff --git a/merge-recursive.c b/merge-recursive.c
index a91208f..82f24ac 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -642,6 +642,23 @@ static int merge_3way(struct merge_options *o,
 	mmfile_t orig, src1, src2;
 	char *name1, *name2;
 	int merge_status;
+	int favor;
+
+	if (o->call_depth)
+		favor = 0;
+	else {
+		switch (o->recursive_variant) {
+		case MERGE_RECURSIVE_OURS:
+			favor = XDL_MERGE_FAVOR_OURS;
+			break;
+		case MERGE_RECURSIVE_THEIRS:
+			favor = XDL_MERGE_FAVOR_THEIRS;
+			break;
+		default:
+			favor = 0;
+			break;
+		}
+	}
 
 	if (strcmp(a->path, b->path)) {
 		name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
@@ -657,7 +674,7 @@ static int merge_3way(struct merge_options *o,
 
 	merge_status = ll_merge(result_buf, a->path, &orig,
 				&src1, name1, &src2, name2,
-				o->call_depth);
+				(!!o->call_depth) | (favor << 1));
 
 	free(name1);
 	free(name2);
@@ -1196,7 +1213,7 @@ int merge_trees(struct merge_options *o,
 {
 	int code, clean;
 
-	if (o->subtree_merge) {
+	if (o->recursive_variant == MERGE_RECURSIVE_SUBTREE) {
 		merge = shift_tree_object(head, merge);
 		common = shift_tree_object(head, common);
 	}
diff --git a/merge-recursive.h b/merge-recursive.h
index fd138ca..39de100 100644
--- a/merge-recursive.h
+++ b/merge-recursive.h
@@ -6,7 +6,11 @@
 struct merge_options {
 	const char *branch1;
 	const char *branch2;
-	unsigned subtree_merge : 1;
+	enum {
+		MERGE_RECURSIVE_SUBTREE = 1,
+		MERGE_RECURSIVE_OURS,
+		MERGE_RECURSIVE_THEIRS,
+	} recursive_variant;
 	unsigned buffer_output : 1;
 	int verbosity;
 	int diff_rename_limit;
diff --git a/strbuf.c b/strbuf.c
index a6153dc..d71a623 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -10,6 +10,15 @@ int prefixcmp(const char *str, const char *prefix)
 			return (unsigned char)*prefix - (unsigned char)*str;
 }
 
+int suffixcmp(const char *str, const char *suffix)
+{
+	int len = strlen(str), suflen = strlen(suffix);
+	if (len < suflen)
+		return -1;
+	else
+		return strcmp(str + len - suflen, suffix);
+}
+
 /*
  * Used as the default ->buf value, so that people can always assume
  * buf is non NULL and ->buf is NUL terminated even for a freshly
diff --git a/t/t6037-merge-ours-theirs.sh b/t/t6037-merge-ours-theirs.sh
new file mode 100755
index 0000000..08c9f79
--- /dev/null
+++ b/t/t6037-merge-ours-theirs.sh
@@ -0,0 +1,56 @@
+#!/bin/sh
+
+test_description='Merge-recursive ours and theirs variants'
+. ./test-lib.sh
+
+test_expect_success setup '
+	for i in 1 2 3 4 5 6 7 8 9
+	do
+		echo "$i"
+	done >file &&
+	git add file &&
+	cp file elif &&
+	git commit -m initial &&
+
+	sed -e "s/1/one/" -e "s/9/nine/" >file <elif &&
+	git commit -a -m ours &&
+
+	git checkout -b side HEAD^ &&
+
+	sed -e "s/9/nueve/" >file <elif &&
+	git commit -a -m theirs &&
+
+	git checkout master^0
+'
+
+test_expect_success 'plain recursive - should conflict' '
+	git reset --hard master &&
+	test_must_fail git merge -s recursive side &&
+	grep nine file &&
+	grep nueve file &&
+	! grep 9 file &&
+	grep one file &&
+	! grep 1 file
+'
+
+test_expect_success 'recursive favouring theirs' '
+	git reset --hard master &&
+	git merge -s recursive -Xtheirs side &&
+	! grep nine file &&
+	grep nueve file &&
+	! grep 9 file &&
+	grep one file &&
+	! grep 1 file
+'
+
+test_expect_success 'recursive favouring ours' '
+	git reset --hard master &&
+	git merge -s recursive -X ours side &&
+	grep nine file &&
+	! grep nueve file &&
+	! grep 9 file &&
+	grep one file &&
+	! grep 1 file
+'
+
+test_done
-- 
cgit v0.10.2-6-g49f6

