Code

branch: allow a no-op "branch -M <current-branch> HEAD"
[git.git] / builtin / merge.c
index 7d593097dea987e580d1e79f010faf23c1f98fb0..2870a6af6fbc868455f2961483cfbfdb065a1a14 100644 (file)
@@ -46,7 +46,7 @@ static const char * const builtin_merge_usage[] = {
 
 static int show_diffstat = 1, shortlog_len, squash;
 static int option_commit = 1, allow_fast_forward = 1;
-static int fast_forward_only;
+static int fast_forward_only, option_edit;
 static int allow_trivial = 1, have_message;
 static struct strbuf merge_msg;
 static struct commit_list *remoteheads;
@@ -189,6 +189,8 @@ static struct option builtin_merge_options[] = {
                "create a single commit instead of doing a merge"),
        OPT_BOOLEAN(0, "commit", &option_commit,
                "perform a commit if the merge succeeds (default)"),
+       OPT_BOOLEAN('e', "edit", &option_edit,
+               "edit message before committing"),
        OPT_BOOLEAN(0, "ff", &allow_fast_forward,
                "allow fast-forward (default)"),
        OPT_BOOLEAN(0, "ff-only", &fast_forward_only,
@@ -314,13 +316,15 @@ static void squash_message(struct commit *commit)
        struct rev_info rev;
        struct strbuf out = STRBUF_INIT;
        struct commit_list *j;
+       const char *filename;
        int fd;
        struct pretty_print_context ctx = {0};
 
        printf(_("Squash commit -- not updating HEAD\n"));
-       fd = open(git_path("SQUASH_MSG"), O_WRONLY | O_CREAT, 0666);
+       filename = git_path("SQUASH_MSG");
+       fd = open(filename, O_WRONLY | O_CREAT, 0666);
        if (fd < 0)
-               die_errno(_("Could not write to '%s'"), git_path("SQUASH_MSG"));
+               die_errno(_("Could not write to '%s'"), filename);
 
        init_revisions(&rev, NULL);
        rev.ignore_merges = 1;
@@ -490,14 +494,16 @@ static void merge_name(const char *remote, struct strbuf *msg)
 
        if (!strcmp(remote, "FETCH_HEAD") &&
                        !access(git_path("FETCH_HEAD"), R_OK)) {
+               const char *filename;
                FILE *fp;
                struct strbuf line = STRBUF_INIT;
                char *ptr;
 
-               fp = fopen(git_path("FETCH_HEAD"), "r");
+               filename = git_path("FETCH_HEAD");
+               fp = fopen(filename, "r");
                if (!fp)
                        die_errno(_("could not open '%s' for reading"),
-                                 git_path("FETCH_HEAD"));
+                                 filename);
                strbuf_getline(&line, fp, '\n');
                fclose(fp);
                ptr = strstr(line.buf, "\tnot-for-merge\t");
@@ -843,30 +849,56 @@ static void add_strategies(const char *string, unsigned attr)
 
 }
 
-static void write_merge_msg(void)
+static void write_merge_msg(struct strbuf *msg)
 {
-       int fd = open(git_path("MERGE_MSG"), O_WRONLY | O_CREAT, 0666);
+       const char *filename = git_path("MERGE_MSG");
+       int fd = open(filename, O_WRONLY | O_CREAT, 0666);
        if (fd < 0)
                die_errno(_("Could not open '%s' for writing"),
-                         git_path("MERGE_MSG"));
-       if (write_in_full(fd, merge_msg.buf, merge_msg.len) != merge_msg.len)
-               die_errno(_("Could not write to '%s'"), git_path("MERGE_MSG"));
+                         filename);
+       if (write_in_full(fd, msg->buf, msg->len) != msg->len)
+               die_errno(_("Could not write to '%s'"), filename);
        close(fd);
 }
 
-static void read_merge_msg(void)
+static void read_merge_msg(struct strbuf *msg)
 {
-       strbuf_reset(&merge_msg);
-       if (strbuf_read_file(&merge_msg, git_path("MERGE_MSG"), 0) < 0)
-               die_errno(_("Could not read from '%s'"), git_path("MERGE_MSG"));
+       const char *filename = git_path("MERGE_MSG");
+       strbuf_reset(msg);
+       if (strbuf_read_file(msg, filename, 0) < 0)
+               die_errno(_("Could not read from '%s'"), filename);
 }
 
-static void run_prepare_commit_msg(void)
+static void write_merge_state(void);
+static void abort_commit(const char *err_msg)
 {
-       write_merge_msg();
+       if (err_msg)
+               error("%s", err_msg);
+       fprintf(stderr,
+               _("Not committing merge; use 'git commit' to complete the merge.\n"));
+       write_merge_state();
+       exit(1);
+}
+
+static void prepare_to_commit(void)
+{
+       struct strbuf msg = STRBUF_INIT;
+       strbuf_addbuf(&msg, &merge_msg);
+       strbuf_addch(&msg, '\n');
+       write_merge_msg(&msg);
        run_hook(get_index_file(), "prepare-commit-msg",
                 git_path("MERGE_MSG"), "merge", NULL, NULL);
-       read_merge_msg();
+       if (option_edit) {
+               if (launch_editor(git_path("MERGE_MSG"), NULL, NULL))
+                       abort_commit(NULL);
+       }
+       read_merge_msg(&msg);
+       stripspace(&msg, option_edit);
+       if (!msg.len)
+               abort_commit(_("Empty commit message."));
+       strbuf_release(&merge_msg);
+       strbuf_addbuf(&merge_msg, &msg);
+       strbuf_release(&msg);
 }
 
 static int merge_trivial(struct commit *head)
@@ -880,7 +912,7 @@ static int merge_trivial(struct commit *head)
        parent->next = xmalloc(sizeof(*parent->next));
        parent->next->item = remoteheads->item;
        parent->next->next = NULL;
-       run_prepare_commit_msg();
+       prepare_to_commit();
        commit_tree(merge_msg.buf, result_tree, parent, result_commit, NULL);
        finish(head, result_commit, "In-index merge");
        drop_save();
@@ -909,9 +941,9 @@ static int finish_automerge(struct commit *head,
                for (j = remoteheads; j; j = j->next)
                        pptr = &commit_list_insert(j->item, pptr)->next;
        }
-       free_commit_list(remoteheads);
        strbuf_addch(&merge_msg, '\n');
-       run_prepare_commit_msg();
+       prepare_to_commit();
+       free_commit_list(remoteheads);
        commit_tree(merge_msg.buf, result_tree, parents, result_commit, NULL);
        strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
        finish(head, result_commit, buf.buf);
@@ -922,13 +954,14 @@ static int finish_automerge(struct commit *head,
 
 static int suggest_conflicts(int renormalizing)
 {
+       const char *filename;
        FILE *fp;
        int pos;
 
-       fp = fopen(git_path("MERGE_MSG"), "a");
+       filename = git_path("MERGE_MSG");
+       fp = fopen(filename, "a");
        if (!fp)
-               die_errno(_("Could not open '%s' for writing"),
-                         git_path("MERGE_MSG"));
+               die_errno(_("Could not open '%s' for writing"), filename);
        fprintf(fp, "\nConflicts:\n");
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
@@ -1018,6 +1051,38 @@ static int setup_with_upstream(const char ***argv)
        return i;
 }
 
+static void write_merge_state(void)
+{
+       const char *filename;
+       int fd;
+       struct commit_list *j;
+       struct strbuf buf = STRBUF_INIT;
+
+       for (j = remoteheads; j; j = j->next)
+               strbuf_addf(&buf, "%s\n",
+                       sha1_to_hex(j->item->object.sha1));
+       filename = git_path("MERGE_HEAD");
+       fd = open(filename, O_WRONLY | O_CREAT, 0666);
+       if (fd < 0)
+               die_errno(_("Could not open '%s' for writing"), filename);
+       if (write_in_full(fd, buf.buf, buf.len) != buf.len)
+               die_errno(_("Could not write to '%s'"), filename);
+       close(fd);
+       strbuf_addch(&merge_msg, '\n');
+       write_merge_msg(&merge_msg);
+
+       filename = git_path("MERGE_MODE");
+       fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+       if (fd < 0)
+               die_errno(_("Could not open '%s' for writing"), filename);
+       strbuf_reset(&buf);
+       if (!allow_fast_forward)
+               strbuf_addf(&buf, "no-ff");
+       if (write_in_full(fd, buf.buf, buf.len) != buf.len)
+               die_errno(_("Could not write to '%s'"), filename);
+       close(fd);
+}
+
 int cmd_merge(int argc, const char **argv, const char *prefix)
 {
        unsigned char result_tree[20];
@@ -1423,33 +1488,8 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
        if (squash)
                finish(head_commit, NULL, NULL);
-       else {
-               int fd;
-               struct commit_list *j;
-
-               for (j = remoteheads; j; j = j->next)
-                       strbuf_addf(&buf, "%s\n",
-                               sha1_to_hex(j->item->object.sha1));
-               fd = open(git_path("MERGE_HEAD"), O_WRONLY | O_CREAT, 0666);
-               if (fd < 0)
-                       die_errno(_("Could not open '%s' for writing"),
-                                 git_path("MERGE_HEAD"));
-               if (write_in_full(fd, buf.buf, buf.len) != buf.len)
-                       die_errno(_("Could not write to '%s'"), git_path("MERGE_HEAD"));
-               close(fd);
-               strbuf_addch(&merge_msg, '\n');
-               write_merge_msg();
-               fd = open(git_path("MERGE_MODE"), O_WRONLY | O_CREAT | O_TRUNC, 0666);
-               if (fd < 0)
-                       die_errno(_("Could not open '%s' for writing"),
-                                 git_path("MERGE_MODE"));
-               strbuf_reset(&buf);
-               if (!allow_fast_forward)
-                       strbuf_addf(&buf, "no-ff");
-               if (write_in_full(fd, buf.buf, buf.len) != buf.len)
-                       die_errno(_("Could not write to '%s'"), git_path("MERGE_MODE"));
-               close(fd);
-       }
+       else
+               write_merge_state();
 
        if (merge_was_ok) {
                fprintf(stderr, _("Automatic merge went well; "