git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH 2/9] apply --whitespace=fix: detect new blank lines at eof correctly

From
Junio C Hamano <gitster@pobox.com>
Date
Sep 4, 2009, 10:55 UTC
Message-ID
<1252061718-11579-3-git-send-email-gitster@pobox.com>
In-Reply-To
<1252061718-11579-1-git-send-email-gitster@pobox.com>

The command tries to strip blank lines at the end of the file added by a patch. However, if the original ends with blank lines, often the patch hunk ends like this:

    @@ -l,5 +m,7 @@$
    _context$
    _context$
    -deleted$
    +$
    +$
    +$
    _$
    _$

where _ stands for SP and $ shows a end-of-line. This example patch adds three trailing blank lines, but the code fails to notice it, because it only pays attention to added blank lines at the very end of the hunk. In this example, the three added blank lines do not appear textually at the end in the patch, even though you can see that they are indeed added at the end, if you rearrange the diff like this:

    @@ -l,5 +m,7 @@$
    _context$
    _context$
    -deleted$
    _$
    _$
    +$
    +$
    +$

Fix this by not resetting the number of (candidate) added blank lines at the end when the loop sees a context line that is empty.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin-apply.c          |    6 ++++++
 t/t4124-apply-ws-rule.sh |   12 ++++++++++++
 2 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/builtin-apply.c b/builtin-apply.c
index 5b5bde4..c5e4048 100644
--- a/builtin-apply.c
+++ b/builtin-apply.c
@@ -1913,6 +1913,7 @@ static int apply_one_fragment(struct image *img, struct fragment *frag,
 		int len = linelen(patch, size);
 		int plen, added;
 		int added_blank_line = 0;
+		int is_blank_context = 0;
 
 		if (!len)
 			break;
@@ -1945,8 +1946,11 @@ static int apply_one_fragment(struct image *img, struct fragment *frag,
 			*new++ = '\n';
 			add_line_info(&preimage, "\n", 1, LINE_COMMON);
 			add_line_info(&postimage, "\n", 1, LINE_COMMON);
+			is_blank_context = 1;
 			break;
 		case ' ':
+			if (plen && patch[1] == '\n')
+				is_blank_context = 1;
 		case '-':
 			memcpy(old, patch + 1, plen);
 			add_line_info(&preimage, old, plen,
@@ -1986,6 +1990,8 @@ static int apply_one_fragment(struct image *img, struct fragment *frag,
 		}
 		if (added_blank_line)
 			new_blank_lines_at_end++;
+		else if (is_blank_context)
+			;
 		else
 			new_blank_lines_at_end = 0;
 		patch += len;
diff --git a/t/t4124-apply-ws-rule.sh b/t/t4124-apply-ws-rule.sh
index 6898722..ba2b7f9 100755
--- a/t/t4124-apply-ws-rule.sh
+++ b/t/t4124-apply-ws-rule.sh
@@ -177,4 +177,16 @@ test_expect_success 'blank at EOF with --whitespace=fix (2)' '
 	test_cmp expect one
 '
 
+test_expect_success 'blank at EOF with --whitespace=fix (3)' '
+	{ echo a; echo b; echo; } >one &&
+	git add one &&
+	{ echo a; echo c; echo; } >expect &&
+	{ cat expect; echo; echo; } >one &&
+	git diff -- one >patch &&
+
+	git checkout one &&
+	git apply --whitespace=fix patch &&
+	test_cmp expect one
+'
+
 test_done
-- 
1.6.4.2.313.g0425f
Previous: Junio C HamanoNext: Johannes Sixt
Message 3 of 14 in “War on blank-at-eof”
  1. 0/9 War on blank-at-eofJunio C Hamano, Sep 4, 2009
  2. 1/9 apply --whitespace=fix: fix handling of blank lines at the eofJunio C Hamano, Sep 4, 2009
  3. 2/9 apply --whitespace=fix: detect new blank lines at eof correctlyJunio C Hamano, Sep 4, 2009
  4. Johannes SixtSep 4, 2009
  5. Junio C HamanoSep 4, 2009
  6. 3/9 apply.c: split check_whitespace() into twoJunio C Hamano, Sep 4, 2009
  7. 4/9 apply --whitespace=warn/error: diagnose blank at EOFJunio C Hamano, Sep 4, 2009
  8. 5/9 apply --whitespace: warn blank but not necessarily empty lines at EOFJunio C Hamano, Sep 4, 2009
  9. 6/9 diff.c: the builtin_diff() deals with only two-file comparisonJunio C Hamano, Sep 4, 2009
  10. 7/9 diff --whitespace=warn/error: obey blank-at-eofJunio C Hamano, Sep 4, 2009
  11. 8/9 diff --whitespace=warn/error: fix blank-at-eof checkJunio C Hamano, Sep 4, 2009
  12. 9/9 diff --color: color blank-at-eofJunio C Hamano, Sep 4, 2009
  13. Thell FowlerSep 5, 2009
  14. Junio C HamanoSep 6, 2009

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.