interdiff: teach show_interdiff() to indent interdiff

A future change will allow "git format-patch --interdiff=<prev> -1" to
insert an interdiff into the commentary section of the lone patch of a
1-patch series. However, to prevent the inserted interdiff from
confusing git-am, as well as human readers, it needs to be indented.
Therefore, teach show_interdiff() how to indent.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/log.c b/builtin/log.c
index 99ddfe8bb0df1c01dd23e9b31c1261793776765d..8078a43d14f014885cc4331cd516efbd5bff6524 100644 (file)
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1086,7 +1086,7 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
 
        if (rev->idiff_oid1) {
                fprintf_ln(rev->diffopt.file, "%s", rev->idiff_title);
-               show_interdiff(rev);
+               show_interdiff(rev, 0);
        }
 }
 

diff --git a/interdiff.c b/interdiff.c
index d0fac10c7c347cf746c0b0297bef7ef842a4a6c9..c81d680a6cee08eaa44a840a6fc8e836bc2a3a1b 100644 (file)
--- a/interdiff.c
+++ b/interdiff.c
@@ -3,15 +3,26 @@
 #include "revision.h"
 #include "interdiff.h"
 
-void show_interdiff(struct rev_info *rev)
+static struct strbuf *idiff_prefix_cb(struct diff_options *opt, void *data)
+{
+       return data;
+}
+
+void show_interdiff(struct rev_info *rev, int indent)
 {
        struct diff_options opts;
+       struct strbuf prefix = STRBUF_INIT;
 
        memcpy(&opts, &rev->diffopt, sizeof(opts));
        opts.output_format = DIFF_FORMAT_PATCH;
+       opts.output_prefix = idiff_prefix_cb;
+       strbuf_addchars(&prefix, ' ', indent);
+       opts.output_prefix_data = &prefix;
        diff_setup_done(&opts);
 
        diff_tree_oid(rev->idiff_oid1, rev->idiff_oid2, "", &opts);
        diffcore_std(&opts);
        diff_flush(&opts);
+
+       strbuf_release(&prefix);
 }

diff --git a/interdiff.h b/interdiff.h
index 793c0144fe39f4d0ffe81f7a7a0e89806bfdd143..01c730a5c9d2c8453b5ec94368800aa755620bde 100644 (file)
--- a/interdiff.h
+++ b/interdiff.h
@@ -3,6 +3,6 @@
 
 struct rev_info;
 
-void show_interdiff(struct rev_info *);
+void show_interdiff(struct rev_info *, int indent);
 
 #endif