builtin rebase: support --onto

The `--onto` option is important, as it allows to rebase a range of
commits onto a different base commit (which gave the command its odd
name: "rebase").

This commit introduces options parsing so that different options can
be added in future commits.

Note: As this commit introduces to the parse_options() call (which
"eats" argv[0]), the argc is now expected to be lower by one after this
patch, compared to before this patch: argv[0] no longer refers to the
command name, but to the first (non-option) command-line parameter.

Signed-off-by: Pratik Karki <predatoramigo@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/rebase.c b/builtin/rebase.c
index e695d8a430f155b46f79c906474ca7b8f5645ec7..742ed3149824b8b6e2b6080ad9c9a2a60339cf0d 100644 (file)
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -16,6 +16,16 @@
 #include "cache-tree.h"
 #include "unpack-trees.h"
 #include "lockfile.h"
+#include "parse-options.h"
+
+static char const * const builtin_rebase_usage[] = {
+       N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
+               "[<upstream>] [<branch>]"),
+       N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
+               "--root [<branch>]"),
+       N_("git rebase --continue | --abort | --skip | --edit-todo"),
+       NULL
+};
 
 static GIT_PATH_FUNC(apply_dir, "rebase-apply")
 static GIT_PATH_FUNC(merge_dir, "rebase-merge")
@@ -301,6 +311,12 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
        int ret, flags;
        struct strbuf msg = STRBUF_INIT;
        struct strbuf revisions = STRBUF_INIT;
+       struct option builtin_rebase_options[] = {
+               OPT_STRING(0, "onto", &options.onto_name,
+                          N_("revision"),
+                          N_("rebase onto given branch instead of upstream")),
+               OPT_END(),
+       };
 
        /*
         * NEEDSWORK: Once the builtin rebase has been tested enough
@@ -318,13 +334,22 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
                        BUG("sane_execvp() returned???");
        }
 
-       if (argc != 2)
-               die(_("Usage: %s <base>"), argv[0]);
+       if (argc == 2 && !strcmp(argv[1], "-h"))
+               usage_with_options(builtin_rebase_usage,
+                                  builtin_rebase_options);
+
        prefix = setup_git_directory();
        trace_repo_setup(prefix);
        setup_work_tree();
 
        git_config(git_default_config, NULL);
+       argc = parse_options(argc, argv, prefix,
+                            builtin_rebase_options,
+                            builtin_rebase_usage, 0);
+
+       if (argc > 2)
+               usage_with_options(builtin_rebase_usage,
+                                  builtin_rebase_options);
 
        switch (options.type) {
        case REBASE_MERGE:
@@ -343,10 +368,10 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
        }
 
        if (!options.root) {
-               if (argc < 2)
+               if (argc < 1)
                        die("TODO: handle @{upstream}");
                else {
-                       options.upstream_name = argv[1];
+                       options.upstream_name = argv[0];
                        argc--;
                        argv++;
                        if (!strcmp(options.upstream_name, "-"))
@@ -377,7 +402,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
         * orig_head -- commit object name of tip of the branch before rebasing
         * head_name -- refs/heads/<that-branch> or "detached HEAD"
         */
-       if (argc > 1)
+       if (argc > 0)
                 die("TODO: handle switch_to");
        else {
                /* Do not need to switch branches, we are already on it. */