Merge branch 'js/rebase-orig-head-fix'

"git rebase" that was reimplemented in C did not set ORIG_HEAD
correctly, which has been corrected.

* js/rebase-orig-head-fix:
built-in rebase: set ORIG_HEAD just once, before the rebase
built-in rebase: demonstrate that ORIG_HEAD is not set correctly
built-in rebase: use the correct reflog when switching branches
built-in rebase: no need to check out `onto` twice

diff --git a/builtin/rebase.c b/builtin/rebase.c
index 52114cbf0d9f98d52a5b48d8806019d14b1c7029..77deebc65c6bd7fbe6261b91cfb78c7ec3f85c2d 100644 (file)
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -369,6 +369,7 @@ static void add_var(struct strbuf *buf, const char *name, const char *value)
 #define RESET_HEAD_HARD (1<<1)
 #define RESET_HEAD_RUN_POST_CHECKOUT_HOOK (1<<2)
 #define RESET_HEAD_REFS_ONLY (1<<3)
+#define RESET_ORIG_HEAD (1<<4)
 
 static int reset_head(struct object_id *oid, const char *action,
                      const char *switch_to_branch, unsigned flags,
@@ -378,6 +379,7 @@ static int reset_head(struct object_id *oid, const char *action,
        unsigned reset_hard = flags & RESET_HEAD_HARD;
        unsigned run_hook = flags & RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
        unsigned refs_only = flags & RESET_HEAD_REFS_ONLY;
+       unsigned update_orig_head = flags & RESET_ORIG_HEAD;
        struct object_id head_oid;
        struct tree_desc desc[2] = { { NULL }, { NULL } };
        struct lock_file lock = LOCK_INIT;
@@ -454,18 +456,21 @@ static int reset_head(struct object_id *oid, const char *action,
        strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
        prefix_len = msg.len;
 
-       if (!get_oid("ORIG_HEAD", &oid_old_orig))
-               old_orig = &oid_old_orig;
-       if (!get_oid("HEAD", &oid_orig)) {
-               orig = &oid_orig;
-               if (!reflog_orig_head) {
-                       strbuf_addstr(&msg, "updating ORIG_HEAD");
-                       reflog_orig_head = msg.buf;
-               }
-               update_ref(reflog_orig_head, "ORIG_HEAD", orig, old_orig, 0,
-                          UPDATE_REFS_MSG_ON_ERR);
-       } else if (old_orig)
-               delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
+       if (update_orig_head) {
+               if (!get_oid("ORIG_HEAD", &oid_old_orig))
+                       old_orig = &oid_old_orig;
+               if (!get_oid("HEAD", &oid_orig)) {
+                       orig = &oid_orig;
+                       if (!reflog_orig_head) {
+                               strbuf_addstr(&msg, "updating ORIG_HEAD");
+                               reflog_orig_head = msg.buf;
+                       }
+                       update_ref(reflog_orig_head, "ORIG_HEAD", orig,
+                                  old_orig, 0, UPDATE_REFS_MSG_ON_ERR);
+               } else if (old_orig)
+                       delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
+       }
+
        if (!reflog_head) {
                strbuf_setlen(&msg, prefix_len);
                strbuf_addstr(&msg, "updating HEAD");
@@ -476,7 +481,7 @@ static int reset_head(struct object_id *oid, const char *action,
                                 detach_head ? REF_NO_DEREF : 0,
                                 UPDATE_REFS_MSG_ON_ERR);
        else {
-               ret = update_ref(reflog_orig_head, switch_to_branch, oid,
+               ret = update_ref(reflog_head, switch_to_branch, oid,
                                 NULL, 0, UPDATE_REFS_MSG_ON_ERR);
                if (!ret)
                        ret = create_symref("HEAD", switch_to_branch,
@@ -1777,7 +1782,8 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
        strbuf_addf(&msg, "%s: checkout %s",
                    getenv(GIT_REFLOG_ACTION_ENVIRONMENT), options.onto_name);
        if (reset_head(&options.onto->object.oid, "checkout", NULL,
-                      RESET_HEAD_DETACH | RESET_HEAD_RUN_POST_CHECKOUT_HOOK,
+                      RESET_HEAD_DETACH | RESET_ORIG_HEAD | 
+                      RESET_HEAD_RUN_POST_CHECKOUT_HOOK,
                       NULL, msg.buf))
                die(_("Could not detach HEAD"));
        strbuf_release(&msg);
@@ -1793,8 +1799,8 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
                strbuf_addf(&msg, "rebase finished: %s onto %s",
                        options.head_name ? options.head_name : "detached HEAD",
                        oid_to_hex(&options.onto->object.oid));
-               reset_head(NULL, "Fast-forwarded", options.head_name, 0,
-                          "HEAD", msg.buf);
+               reset_head(NULL, "Fast-forwarded", options.head_name,
+                          RESET_HEAD_REFS_ONLY, "HEAD", msg.buf);
                strbuf_release(&msg);
                ret = !!finish_rebase(&options);
                goto cleanup;

diff --git a/t/t3400-rebase.sh b/t/t3400-rebase.sh
index 3e73f7584ce7d3a23e7e75d0f71bd595f5f822a3..460d0523be6f35e4477a010edd365c1f8fbd431c 100755 (executable)
--- a/t/t3400-rebase.sh
+++ b/t/t3400-rebase.sh
@@ -59,6 +59,14 @@ test_expect_success 'rebase against master' '
        git rebase master
 '
 
+test_expect_success 'rebase sets ORIG_HEAD to pre-rebase state' '
+       git checkout -b orig-head topic &&
+       pre="$(git rev-parse --verify HEAD)" &&
+       git rebase master &&
+       test_cmp_rev "$pre" ORIG_HEAD &&
+       ! test_cmp_rev "$pre" HEAD
+'
+
 test_expect_success 'rebase, with <onto> and <upstream> specified as :/quuxery' '
        test_when_finished "git branch -D torebase" &&
        git checkout -b torebase my-topic-branch^ &&