Try normalizing files to avoid delete/modify conflicts when merging
If a file is modified due to normalization on one branch, and deleted on
another, a merge of the two branches will result in a delete/modify
conflict for that file even if it is otherwise unchanged.
Try to avoid the conflict by normalizing and comparing the "base" file
and the modified file when their sha1s differ. If they compare equal,
the file is considered unmodified and is deleted.
Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/merge-recursive.c b/merge-recursive.c
index 206c103..5ad8fc9 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -1056,6 +1056,53 @@
return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
}
+static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
+{
+ void *buf;
+ enum object_type type;
+ unsigned long size;
+ buf = read_sha1_file(sha1, &type, &size);
+ if (!buf)
+ return error("cannot read object %s", sha1_to_hex(sha1));
+ if (type != OBJ_BLOB) {
+ free(buf);
+ return error("object %s is not a blob", sha1_to_hex(sha1));
+ }
+ strbuf_attach(dst, buf, size, size + 1);
+ return 0;
+}
+
+static int blob_unchanged(const unsigned char *o_sha,
+ const unsigned char *a_sha,
+ const char *path)
+{
+ struct strbuf o = STRBUF_INIT;
+ struct strbuf a = STRBUF_INIT;
+ int ret = 0; /* assume changed for safety */
+
+ if (sha_eq(o_sha, a_sha))
+ return 1;
+ if (!merge_renormalize)
+ return 0;
+
+ assert(o_sha && a_sha);
+ if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
+ goto error_return;
+ /*
+ * Note: binary | is used so that both renormalizations are
+ * performed. Comparison can be skipped if both files are
+ * unchanged since their sha1s have already been compared.
+ */
+ if (renormalize_buffer(path, o.buf, o.len, &o) |
+ renormalize_buffer(path, a.buf, o.len, &a))
+ ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
+
+error_return:
+ strbuf_release(&o);
+ strbuf_release(&a);
+ return ret;
+}
+
/* Per entry merge function */
static int process_entry(struct merge_options *o,
const char *path, struct stage_data *entry)
@@ -1075,8 +1122,8 @@
if (o_sha && (!a_sha || !b_sha)) {
/* Case A: Deleted in one */
if ((!a_sha && !b_sha) ||
- (sha_eq(a_sha, o_sha) && !b_sha) ||
- (!a_sha && sha_eq(b_sha, o_sha))) {
+ (!b_sha && blob_unchanged(o_sha, a_sha, path)) ||
+ (!a_sha && blob_unchanged(o_sha, b_sha, path))) {
/* Deleted in both or deleted in one and
* unchanged in the other */
if (a_sha)
diff --git a/t/t6038-merge-text-auto.sh b/t/t6038-merge-text-auto.sh
index 127baf8..d1ab86e 100755
--- a/t/t6038-merge-text-auto.sh
+++ b/t/t6038-merge-text-auto.sh
@@ -51,7 +51,7 @@
test_cmp file file.temp
'
-test_expect_failure 'Test delete/normalize conflict' '
+test_expect_success 'Test delete/normalize conflict' '
git checkout side &&
git reset --hard initial &&
git rm file &&
