work around an obnoxious bash "safety feature" on OpenBSD

diff --git a/builtin-checkout.c b/builtin-checkout.c
index 64f3a11ae1d415c466def8eccefe9dbc5b6b3926..527781728e0706b906a94ddfb8ee2e8bb06fa05e 100644 (file)
--- a/builtin-checkout.c
+++ b/builtin-checkout.c
@@ -17,6 +17,7 @@
 #include "blob.h"
 #include "xdiff-interface.h"
 #include "ll-merge.h"
+#include "resolve-undo.h"
 
 static const char * const checkout_usage[] = {
        "git checkout [options] <branch>",
@@ -167,7 +168,7 @@ static int checkout_merged(int pos, struct checkout *state)
        fill_mm(active_cache[pos+2]->sha1, &theirs);
 
        status = ll_merge(&result_buf, path, &ancestor,
-                         &ours, "ours", &theirs, "theirs", 1);
+                         &ours, "ours", &theirs, "theirs", 0);
        free(ancestor.ptr);
        free(ours.ptr);
        free(theirs.ptr);
@@ -234,6 +235,10 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec,
        if (report_path_error(ps_matched, pathspec, 0))
                return 1;
 
+       /* "checkout -m path" to recreate conflicted state */
+       if (opts->merge)
+               unmerge_cache(pathspec);
+
        /* Any unmerged paths? */
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
@@ -370,6 +375,7 @@ static int merge_working_tree(struct checkout_opts *opts,
        if (read_cache_preload(NULL) < 0)
                return error("corrupt index file");
 
+       resolve_undo_clear();
        if (opts->force) {
                ret = reset_tree(new->commit->tree, opts, 1);
                if (ret)
@@ -397,7 +403,7 @@ static int merge_working_tree(struct checkout_opts *opts,
                topts.initial_checkout = is_cache_unborn();
                topts.update = 1;
                topts.merge = 1;
-               topts.gently = opts->merge;
+               topts.gently = opts->merge && old->commit;
                topts.verbose_update = !opts->quiet;
                topts.fn = twoway_merge;
                topts.dir = xcalloc(1, sizeof(*topts.dir));
@@ -422,7 +428,13 @@ static int merge_working_tree(struct checkout_opts *opts,
                        struct merge_options o;
                        if (!opts->merge)
                                return 1;
-                       parse_commit(old->commit);
+
+                       /*
+                        * Without old->commit, the below is the same as
+                        * the two-tree unpack we already tried and failed.
+                        */
+                       if (!old->commit)
+                               return 1;
 
                        /* Do more real merge */
 
@@ -690,7 +702,10 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
         * case 3: git checkout <something> [<paths>]
         *
         *   With no paths, if <something> is a commit, that is to
-        *   switch to the branch or detach HEAD at it.
+        *   switch to the branch or detach HEAD at it.  As a special case,
+        *   if <something> is A...B (missing A or B means HEAD but you can
+        *   omit at most one side), and if there is a unique merge base
+        *   between A and B, A...B names that merge base.
         *
         *   With no paths, if <something> is _not_ a commit, no -t nor -b
         *   was given, and there is a tracking branch whose name is
@@ -716,7 +731,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                if (!strcmp(arg, "-"))
                        arg = "@{-1}";
 
-               if (get_sha1(arg, rev)) {
+               if (get_sha1_mb(arg, rev)) {
                        if (has_dash_dash)          /* case (1) */
                                die("invalid reference: %s", arg);
                        if (!patch_mode &&
@@ -743,8 +758,10 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                new.name = arg;
                if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
                        setup_branch_path(&new);
-                       if (resolve_ref(new.path, rev, 1, NULL))
-                               new.commit = lookup_commit_reference(rev);
+
+                       if ((check_ref_format(new.path) == CHECK_REF_FORMAT_OK) &&
+                           resolve_ref(new.path, rev, 1, NULL))
+                               ;
                        else
                                new.path = NULL;
                        parse_commit(new.commit);