Subject: [PATCHv5 14/17] diff.c: convert diff_summary to use emit_line_*

From: Stefan Beller <[email-masked]>
Date: Wed, 24 May 2017 14:40:33 -0700

In a later patch, I want to propose an option to detect&color
moved lines in a diff, which cannot be done in a one-pass over
the diff. Instead we need to go over the whole diff twice,
because we cannot detect the first line of the two corresponding
lines (+ and -) that got moved.

So to prepare the diff machinery for two pass algorithms
(i.e. buffer it all up and then operate on the result),
move all emissions to places, such that the only emitting
function is emit_line_0.

This covers diff_summary.

Signed-off-by: Stefan Beller <[email-masked]>
Signed-off-by: Junio C Hamano <[email-masked]>
---
 diff.c | 64 ++++++++++++++++++++++++++++++++++------------------------------
 1 file changed, 34 insertions(+), 30 deletions(-)

diff --git a/diff.c b/diff.c
index 8ebe673331..76cafde4be 100644
--- a/diff.c
+++ b/diff.c
@@ -4504,67 +4504,71 @@ static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
 	}
 }
 
-static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
+static void show_file_mode_name(struct diff_options *opt, const char *newdelete, struct diff_filespec *fs)
 {
+	struct strbuf sb = STRBUF_INIT;
 	if (fs->mode)
-		fprintf(file, " %s mode %06o ", newdelete, fs->mode);
+		strbuf_addf(&sb, " %s mode %06o ", newdelete, fs->mode);
 	else
-		fprintf(file, " %s ", newdelete);
-	write_name_quoted(fs->path, file, '\n');
-}
+		strbuf_addf(&sb, " %s ", newdelete);
 
+	quote_c_style(fs->path, &sb, NULL, 0);
+	strbuf_addch(&sb, '\n');
+	emit_line(opt, NULL, NULL, 1, 0, sb.buf, sb.len);
+	strbuf_release(&sb);
+}
 
-static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
-		const char *line_prefix)
+static void show_mode_change(struct diff_options *opt, struct diff_filepair *p,
+		int show_name)
 {
 	if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
-		fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
-			p->two->mode, show_name ? ' ' : '\n');
+		struct strbuf sb = STRBUF_INIT;
 		if (show_name) {
-			write_name_quoted(p->two->path, file, '\n');
+			strbuf_addch(&sb, ' ');
+			quote_c_style(p->two->path, &sb, NULL, 0);
 		}
+		emit_line_fmt(opt, NULL, NULL, 1,
+			      " mode change %06o => %06o%s\n",
+			      p->one->mode, p->two->mode,
+			      show_name ? sb.buf : "");
+		strbuf_release(&sb);
 	}
 }
 
-static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
-			const char *line_prefix)
+static void show_rename_copy(struct diff_options *opt, const char *renamecopy,
+		struct diff_filepair *p)
 {
 	char *names = pprint_rename(p->one->path, p->two->path);
-
-	fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
+	emit_line_fmt(opt, NULL, NULL, 1, " %s %s (%d%%)\n",
+		      renamecopy, names, similarity_index(p));
 	free(names);
-	show_mode_change(file, p, 0, line_prefix);
+	show_mode_change(opt, p, 0);
 }
 
 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
 {
-	FILE *file = opt->file;
-	const char *line_prefix = diff_line_prefix(opt);
-
 	switch(p->status) {
 	case DIFF_STATUS_DELETED:
-		fputs(line_prefix, file);
-		show_file_mode_name(file, "delete", p->one);
+		show_file_mode_name(opt, "delete", p->one);
 		break;
 	case DIFF_STATUS_ADDED:
-		fputs(line_prefix, file);
-		show_file_mode_name(file, "create", p->two);
+		show_file_mode_name(opt, "create", p->two);
 		break;
 	case DIFF_STATUS_COPIED:
-		fputs(line_prefix, file);
-		show_rename_copy(file, "copy", p, line_prefix);
+		show_rename_copy(opt, "copy", p);
 		break;
 	case DIFF_STATUS_RENAMED:
-		fputs(line_prefix, file);
-		show_rename_copy(file, "rename", p, line_prefix);
+		show_rename_copy(opt, "rename", p);
 		break;
 	default:
 		if (p->score) {
-			fprintf(file, "%s rewrite ", line_prefix);
-			write_name_quoted(p->two->path, file, ' ');
-			fprintf(file, "(%d%%)\n", similarity_index(p));
+			struct strbuf sb = STRBUF_INIT;
+			strbuf_addstr(&sb, " rewrite ");
+			quote_c_style(p->two->path, &sb, NULL, 0);
+			strbuf_addf(&sb, " (%d%%)\n", similarity_index(p));
+			emit_line(opt, NULL, NULL, 1, 0, sb.buf, sb.len);
 		}
-		show_mode_change(file, p, !p->score, line_prefix);
+		show_mode_change(opt, p, !p->score);
 		break;
 	}
 }
-- 
2.13.0.18.g7d86cc8ba0