combine-diff: do not punt on removed or added files.

When we remove a file, the parents' contents are all removed so
it is not that interesting to show all of them, but the fact it
was removed when all parents had it *is* unusual.  When we add a
file, similarly the fact it was added when no parent wanted it
*is* unusual, and in addition the result matters, so show it.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/combine-diff.c b/combine-diff.c
index 506c095..6a9f368 100644 (file)
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -8,8 +8,6 @@ static int uninteresting(struct diff_filepair *p)
 {
        if (diff_unmodified_pair(p))
                return 1;
-       if (!S_ISREG(p->one->mode) || !S_ISREG(p->two->mode))
-               return 1;
        return 0;
 }
 
@@ -226,6 +224,9 @@ static void combine_diff(const unsigned char *parent, const char *ourtmp,
        unsigned long nmask = (1UL << n);
        struct sline *lost_bucket = NULL;
 
+       if (!cnt)
+               return; /* result deleted */
+
        write_temp_blob(parent_tmp, parent);
        sprintf(cmd, "diff --unified=0 -La/x -Lb/x '%s' '%s'",
                parent_tmp, ourtmp);
@@ -542,6 +543,9 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent)
        int i;
        unsigned long lno = 0;
 
+       if (!cnt)
+               return; /* result deleted */
+
        while (1) {
                struct sline *sl = &sline[lno];
                int hunk_end;
@@ -610,6 +614,8 @@ static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
                        sline->flag |= imask;
                sline++;
        }
+       /* the overall size of the file (sline[cnt]) */
+       sline->p_lno[i] = sline->p_lno[j];
 }
 
 int show_combined_diff(struct combine_diff_path *elem, int num_parent,
@@ -665,27 +671,26 @@ int show_combined_diff(struct combine_diff_path *elem, int num_parent,
                if (*cp == '\n')
                        cnt++;
        }
-       if (result[size-1] != '\n')
+       if (size && result[size-1] != '\n')
                cnt++; /* incomplete line */
 
        sline = xcalloc(cnt+1, sizeof(*sline));
        ep = result;
        sline[0].bol = result;
+       for (lno = 0; lno <= cnt; lno++) {
+               sline[lno].lost_tail = &sline[lno].lost_head;
+               sline[lno].flag = 0;
+       }
        for (lno = 0, cp = result; cp - result < size; cp++) {
                if (*cp == '\n') {
-                       sline[lno].lost_tail = &sline[lno].lost_head;
                        sline[lno].len = cp - sline[lno].bol;
-                       sline[lno].flag = 0;
                        lno++;
                        if (lno < cnt)
                                sline[lno].bol = cp + 1;
                }
        }
-       if (result[size-1] != '\n') {
-               sline[cnt-1].lost_tail = &sline[cnt-1].lost_head;
+       if (size && result[size-1] != '\n')
                sline[cnt-1].len = size - (sline[cnt-1].bol - result);
-               sline[cnt-1].flag = 0;
-       }
 
        sline[0].p_lno = xcalloc((cnt+1) * num_parent, sizeof(unsigned long));
        for (lno = 0; lno < cnt; lno++)
@@ -750,7 +755,6 @@ int show_combined_diff(struct combine_diff_path *elem, int num_parent,
                        }
                        printf("..%06o\n", elem->mode);
                }
-               /* if (show_hunks) perhaps */
                dump_sline(sline, cnt, num_parent);
        }
        if (ourtmp == ourtmp_buf)