Merge branch 'jk/log-missing-default-HEAD' into maint

"git init empty && git -C empty log" said "bad default revision 'HEAD'",
which was found to be a bit confusing to new users.

* jk/log-missing-default-HEAD:
log: diagnose empty HEAD more clearly

diff --git a/revision.c b/revision.c
index ab97ffd4590cc41743d4bb828a9c5bdb1a00cce9..9b9d77dc439d6a6c8e25c58454833804116db14a 100644 (file)
--- a/revision.c
+++ b/revision.c
@@ -2173,6 +2173,21 @@ static int handle_revision_pseudo_opt(const char *submodule,
        return 1;
 }
 
+static void NORETURN diagnose_missing_default(const char *def)
+{
+       unsigned char sha1[20];
+       int flags;
+       const char *refname;
+
+       refname = resolve_ref_unsafe(def, 0, sha1, &flags);
+       if (!refname || !(flags & REF_ISSYMREF) || (flags & REF_ISBROKEN))
+               die(_("your current branch appears to be broken"));
+
+       skip_prefix(refname, "refs/heads/", &refname);
+       die(_("your current branch '%s' does not have any commits yet"),
+           refname);
+}
+
 /*
  * Parse revision information, filling in the "rev_info" structure,
  * and removing the used arguments from the argument list.
@@ -2302,7 +2317,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s
                struct object *object;
                struct object_context oc;
                if (get_sha1_with_context(revs->def, 0, sha1, &oc))
-                       die("bad default revision '%s'", revs->def);
+                       diagnose_missing_default(revs->def);
                object = get_reference(revs, revs->def, sha1, 0);
                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
        }

diff --git a/t/t4202-log.sh b/t/t4202-log.sh
index 1b2e981a0011d520d1a7d8bb8d0a5fd7892bacc4..19277dd3618019a97ef0631cc4a808f5e5bcc653 100755 (executable)
--- a/t/t4202-log.sh
+++ b/t/t4202-log.sh
@@ -871,4 +871,18 @@ test_expect_success 'log --graph --no-walk is forbidden' '
        test_must_fail git log --graph --no-walk
 '
 
+test_expect_success 'log diagnoses bogus HEAD' '
+       git init empty &&
+       test_must_fail git -C empty log 2>stderr &&
+       test_i18ngrep does.not.have.any.commits stderr &&
+       echo 1234abcd >empty/.git/refs/heads/master &&
+       test_must_fail git -C empty log 2>stderr &&
+       test_i18ngrep broken stderr &&
+       echo "ref: refs/heads/invalid.lock" >empty/.git/HEAD &&
+       test_must_fail git -C empty log 2>stderr &&
+       test_i18ngrep broken stderr &&
+       test_must_fail git -C empty log --default totally-bogus 2>stderr &&
+       test_i18ngrep broken stderr
+'
+
 test_done