[PATCH 3/4] reflog-walk: clean up "flag" field of commit_reflog struct

[Jeff King]

When we prepare to walk a reflog, we parse the specification
and pull some information from it, such as which reflog to
look in (e.g., HEAD), and where to start (e.g., HEAD@{10} or
HEAD@{yesterday}). The resulting struct has a "recno" field
to show where in the reflog we are starting. It also has a
"flag" field; if true, it means the recno field came from
parsing a date like HEAD@{yesterday}.

There are two problems with this:

  1. "flag" is an absolutely terrible name, as it conveys
     nothing about the meaning

  2. you can tell "HEAD" from "HEAD@{yesterday}", but you
     can't differentiate "HEAD" from "HEAD{0}"

This patch converts the flag into a tri-state (and gives it
a better name!).

Signed-off-by: Jeff King <p...@peff.net>
---
 reflog-walk.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/reflog-walk.c b/reflog-walk.c
index 86d1884..3549318 100644
--- a/reflog-walk.c
+++ b/reflog-walk.c
@@ -126,7 +126,12 @@ static void add_commit_info(struct commit *commit, void 
*util,
 }
 
 struct commit_reflog {
-       int flag, recno;
+       int recno;
+       enum selector_type {
+               SELECTOR_NONE,
+               SELECTOR_INDEX,
+               SELECTOR_DATE
+       } selector;
        struct complete_reflogs *reflogs;
 };
 
@@ -150,6 +155,7 @@ int add_reflog_for_walk(struct reflog_walk_info *info,
        struct complete_reflogs *reflogs;
        char *branch, *at = strchr(name, '@');
        struct commit_reflog *commit_reflog;
+       enum selector_type selector = SELECTOR_NONE;
 
        if (commit->object.flags & UNINTERESTING)
                die ("Cannot walk reflogs for %s", name);
@@ -162,7 +168,10 @@ int add_reflog_for_walk(struct reflog_walk_info *info,
                if (*ep != '}') {
                        recno = -1;
                        timestamp = approxidate(at + 2);
+                       selector = SELECTOR_DATE;
                }
+               else
+                       selector = SELECTOR_INDEX;
        } else
                recno = 0;
 
@@ -200,7 +209,6 @@ int add_reflog_for_walk(struct reflog_walk_info *info,
 
        commit_reflog = xcalloc(sizeof(struct commit_reflog), 1);
        if (recno < 0) {
-               commit_reflog->flag = 1;
                commit_reflog->recno = get_reflog_recno_by_time(reflogs, 
timestamp);
                if (commit_reflog->recno < 0) {
                        free(branch);
@@ -209,6 +217,7 @@ int add_reflog_for_walk(struct reflog_walk_info *info,
                }
        } else
                commit_reflog->recno = reflogs->nr - recno - 1;
+       commit_reflog->selector = selector;
        commit_reflog->reflogs = reflogs;
 
        add_commit_info(commit, commit_reflog, &info->reflogs);
@@ -267,7 +276,7 @@ void get_reflog_selector(struct strbuf *sb,
        }
 
        strbuf_addf(sb, "%s@{", printed_ref);
-       if (commit_reflog->flag || dmode) {
+       if (commit_reflog->selector == SELECTOR_DATE || dmode) {
                info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
                strbuf_addstr(sb, show_date(info->timestamp, info->tz, dmode));
        } else {
-- 
1.7.10.1.10.ge534bc3