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[PATCH 4/4] diff -B: colour whitespace errors

From
Junio C Hamano <gitster@pobox.com>
Date
Sep 15, 2009, 06:15 UTC
Message-ID
<1252995306-32329-5-git-send-email-gitster@pobox.com>
In-Reply-To
<1252995306-32329-1-git-send-email-gitster@pobox.com>

We used to send the old and new contents more or less straight out to the output with only the original "old is red, new is green" colouring. Now all the necessary support routines have been prepared, call them with a line of data at a time from the output code and have them check and color whitespace errors in exactly the same way as they are called from the low level diff callback routines.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 diff.c |   75 +++++++++++++++++++++++++++++++++++++++++----------------------
 1 files changed, 49 insertions(+), 26 deletions(-)
diff --git a/diff.c b/diff.c
index baf46ab..b6d40d7 100644
--- a/diff.c
+++ b/diff.c
@@ -296,28 +296,6 @@ static void print_line_count(FILE *file, int count)
 	}
 }
 
-static void copy_file_with_prefix(FILE *file,
-				  int prefix, const char *data, int size,
-				  const char *set, const char *reset)
-{
-	int ch, nl_just_seen = 1;
-	while (0 < size--) {
-		ch = *data++;
-		if (nl_just_seen) {
-			fputs(set, file);
-			putc(prefix, file);
-		}
-		if (ch == '\n') {
-			nl_just_seen = 1;
-			fputs(reset, file);
-		} else
-			nl_just_seen = 0;
-		putc(ch, file);
-	}
-	if (!nl_just_seen)
-		fprintf(file, "%s\n\\ No newline at end of file\n", reset);
-}
-
 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 {
 	if (!DIFF_FILE_VALID(one)) {
@@ -436,6 +414,38 @@ static void emit_add_line(const char *reset,
 	}
 }
 
+static void emit_rewrite_lines(struct emit_callback *ecb,
+			       int prefix, const char *data, int size)
+{
+	const char *endp = NULL;
+	static const char *nneof = " No newline at end of file\n";
+	const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
+	const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
+
+	while (0 < size) {
+		int len;
+
+		endp = memchr(data, '\n', size);
+		len = endp ? (endp - data + 1) : size;
+		if (prefix != '+') {
+			ecb->lno_in_preimage++;
+			emit_line_0(ecb->file, old, reset, '-',
+				    data, len);
+		} else {
+			ecb->lno_in_postimage++;
+			emit_add_line(reset, ecb, data, len);
+		}
+		size -= len;
+		data += len;
+	}
+	if (!endp) {
+		const char *plain = diff_get_color(ecb->color_diff,
+						   DIFF_PLAIN);
+		emit_line_0(ecb->file, plain, reset, '\\',
+			    nneof, strlen(nneof));
+	}
+}
+
 static void emit_rewrite_diff(const char *name_a,
 			      const char *name_b,
 			      struct diff_filespec *one,
@@ -447,10 +457,23 @@ static void emit_rewrite_diff(const char *name_a,
 	const char *name_a_tab, *name_b_tab;
 	const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
 	const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
-	const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
-	const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
 	const char *reset = diff_get_color(color_diff, DIFF_RESET);
 	static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
+	struct emit_callback ecbdata;
+
+	memset(&ecbdata, 0, sizeof(ecbdata));
+	ecbdata.color_diff = color_diff;
+	ecbdata.found_changesp = &o->found_changes;
+	ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
+	ecbdata.file = o->file;
+	if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
+		mmfile_t mf1, mf2;
+		fill_mmfile(&mf1, one);
+		fill_mmfile(&mf2, two);
+		check_blank_at_eof(&mf1, &mf2, &ecbdata);
+	}
+	ecbdata.lno_in_preimage = 1;
+	ecbdata.lno_in_postimage = 1;
 
 	name_a += (*name_a == '/');
 	name_b += (*name_b == '/');
@@ -475,9 +498,9 @@ static void emit_rewrite_diff(const char *name_a,
 	print_line_count(o->file, lc_b);
 	fprintf(o->file, " @@%s\n", reset);
 	if (lc_a)
-		copy_file_with_prefix(o->file, '-', one->data, one->size, old, reset);
+		emit_rewrite_lines(&ecbdata, '-', one->data, one->size);
 	if (lc_b)
-		copy_file_with_prefix(o->file, '+', two->data, two->size, new, reset);
+		emit_rewrite_lines(&ecbdata, '+', two->data, two->size);
 }
 
 struct diff_words_buffer {
-- 
1.6.5.rc1.54.g4aad
Previous: Junio C HamanoNext: Nanako Shiraishi
Message 5 of 7 in “Colouring whitespace errors in diff -B output”
  1. 0/4 Colouring whitespace errors in diff -B outputJunio C Hamano, Sep 15, 2009
  2. 1/4 diff.c: shuffling code aroundJunio C Hamano, Sep 15, 2009
  3. 2/4 diff.c: split emit_line() from the first char and the rest of the lineJunio C Hamano, Sep 15, 2009
  4. 3/4 diff.c: emit_add_line() takes only the rest of the lineJunio C Hamano, Sep 15, 2009
  5. 4/4 diff -B: colour whitespace errorsJunio C Hamano, Sep 15, 2009
  6. Nanako ShiraishiSep 15, 2009
  7. Junio C HamanoSep 15, 2009

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