diff -c/--cc: do not include uninteresting deletion before leading context

diff --git a/combine-diff.c b/combine-diff.c
index 5a658dc0d54f91faee450e4f9ebacc1a6338478f..b6af32455c30964516ffd2cc01576bed7d8e98ec 100644 (file)
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -84,6 +84,7 @@ struct sline {
        /* bit 0 up to (N-1) are on if the parent has this line (i.e.
         * we did not change it).
         * bit N is used for "interesting" lines, including context.
+        * bit (N+1) is used for "do not show deletion before this".
         */
        unsigned long flag;
        unsigned long *p_lno;
@@ -226,7 +227,7 @@ static void combine_diff(const unsigned char *parent, mmfile_t *result_file,
        state.num_parent = num_parent;
        state.n = n;
 
-       xdl_diff(&parent_file, result_file, &xpp, &xecfg, &ecb);
+       xdi_diff(&parent_file, result_file, &xpp, &xecfg, &ecb);
        free(parent_file.ptr);
 
        /* Assign line numbers for this parent.
@@ -308,6 +309,7 @@ static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
 {
        unsigned long all_mask = (1UL<<num_parent) - 1;
        unsigned long mark = (1UL<<num_parent);
+       unsigned long no_pre_delete = (2UL<<num_parent);
        unsigned long i;
 
        /* Two groups of interesting lines may have a short gap of
@@ -329,7 +331,7 @@ static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
 
                /* Paint a few lines before the first interesting line. */
                while (j < i)
-                       sline[j++].flag |= mark;
+                       sline[j++].flag |= mark | no_pre_delete;
 
        again:
                /* we know up to i is to be included.  where does the
@@ -502,6 +504,7 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                       int use_color)
 {
        unsigned long mark = (1UL<<num_parent);
+       unsigned long no_pre_delete = (2UL<<num_parent);
        int i;
        unsigned long lno = 0;
        const char *c_frag = diff_get_color(use_color, DIFF_FRAGINFO);
@@ -581,7 +584,7 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                        int j;
                        unsigned long p_mask;
                        sl = &sline[lno++];
-                       ll = sl->lost_head;
+                       ll = (sl->flag & no_pre_delete) ? NULL : sl->lost_head;
                        while (ll) {
                                fputs(c_old, stdout);
                                for (j = 0; j < num_parent; j++) {
@@ -646,12 +649,19 @@ static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
        sline->p_lno[i] = sline->p_lno[j];
 }
 
-static void dump_quoted_path(const char *prefix, const char *path,
+static void dump_quoted_path(const char *head,
+                            const char *prefix,
+                            const char *path,
                             const char *c_meta, const char *c_reset)
 {
-       printf("%s%s", c_meta, prefix);
-       quote_c_style(path, NULL, stdout, 0);
-       printf("%s\n", c_reset);
+       static struct strbuf buf = STRBUF_INIT;
+
+       strbuf_reset(&buf);
+       strbuf_addstr(&buf, c_meta);
+       strbuf_addstr(&buf, head);
+       quote_two_c_style(&buf, prefix, path, 0);
+       strbuf_addstr(&buf, c_reset);
+       puts(buf.buf);
 }
 
 static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
@@ -793,7 +803,7 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                if (rev->loginfo && !rev->no_commit_id)
                        show_log(rev, opt->msg_sep);
                dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
-                                elem->path, c_meta, c_reset);
+                                "", elem->path, c_meta, c_reset);
                printf("%sindex ", c_meta);
                for (i = 0; i < num_parent; i++) {
                        abb = find_unique_abbrev(elem->parent[i].sha1,
@@ -829,14 +839,19 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                        printf("%s\n", c_reset);
                }
                if (added)
-                       dump_quoted_path("--- /dev/", "null", c_meta, c_reset);
+                       dump_quoted_path("--- ", "", "/dev/null",
+                                        c_meta, c_reset);
                else
-                       dump_quoted_path("--- a/", elem->path, c_meta, c_reset);
+                       dump_quoted_path("--- ", opt->a_prefix, elem->path,
+                                        c_meta, c_reset);
                if (deleted)
-                       dump_quoted_path("+++ /dev/", "null", c_meta, c_reset);
+                       dump_quoted_path("+++ ", "", "/dev/null",
+                                        c_meta, c_reset);
                else
-                       dump_quoted_path("+++ b/", elem->path, c_meta, c_reset);
-               dump_sline(sline, cnt, num_parent, DIFF_OPT_TST(opt, COLOR_DIFF));
+                       dump_quoted_path("+++ ", opt->b_prefix, elem->path,
+                                        c_meta, c_reset);
+               dump_sline(sline, cnt, num_parent,
+                          DIFF_OPT_TST(opt, COLOR_DIFF));
        }
        free(result);