git-commit-vandalism/builtin/merge-recursive.c
Justin Frankel 58a1ece478 merge-recursive --patience
Teach the merge-recursive strategy a --patience option to use the
"patience diff" algorithm, which tends to improve results when
cherry-picking a patch that reorders functions at the same time as
refactoring them.

To support this, struct merge_options and ll_merge_options gain an
xdl_opts member, so programs can use arbitrary xdiff flags (think
"XDF_IGNORE_WHITESPACE") in a git-aware merge.

git merge and git rebase can be passed the -Xpatience option to
use this.

[jn: split from --ignore-space patch; with documentation]

Signed-off-by: Justin Frankel <justin@cockos.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-26 09:20:03 -07:00

78 lines
1.9 KiB
C

#include "cache.h"
#include "commit.h"
#include "tag.h"
#include "merge-recursive.h"
#include "xdiff-interface.h"
static const char *better_branch_name(const char *branch)
{
static char githead_env[8 + 40 + 1];
char *name;
if (strlen(branch) != 40)
return branch;
sprintf(githead_env, "GITHEAD_%s", branch);
name = getenv(githead_env);
return name ? name : branch;
}
int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
{
const unsigned char *bases[21];
unsigned bases_count = 0;
int i, failed;
unsigned char h1[20], h2[20];
struct merge_options o;
struct commit *result;
init_merge_options(&o);
if (argv[0] && !suffixcmp(argv[0], "-subtree"))
o.subtree_shift = "";
if (argc < 4)
usagef("%s <base>... -- <head> <remote> ...", argv[0]);
for (i = 1; i < argc; ++i) {
const char *arg = argv[i];
if (!prefixcmp(arg, "--")) {
if (!arg[2])
break;
if (parse_merge_opt(&o, arg + 2))
die("Unknown option %s", arg);
continue;
}
if (bases_count < ARRAY_SIZE(bases)-1) {
unsigned char *sha = xmalloc(20);
if (get_sha1(argv[i], sha))
die("Could not parse object '%s'", argv[i]);
bases[bases_count++] = sha;
}
else
warning("Cannot handle more than %d bases. "
"Ignoring %s.",
(int)ARRAY_SIZE(bases)-1, argv[i]);
}
if (argc - i != 3) /* "--" "<head>" "<remote>" */
die("Not handling anything other than two heads merge.");
o.branch1 = argv[++i];
o.branch2 = argv[++i];
if (get_sha1(o.branch1, h1))
die("Could not resolve ref '%s'", o.branch1);
if (get_sha1(o.branch2, h2))
die("Could not resolve ref '%s'", o.branch2);
o.branch1 = better_branch_name(o.branch1);
o.branch2 = better_branch_name(o.branch2);
if (o.verbosity >= 3)
printf("Merging %s with %s\n", o.branch1, o.branch2);
failed = merge_recursive_generic(&o, h1, h2, bases_count, bases, &result);
if (failed < 0)
return 128; /* die() error code */
return failed;
}