diff: shortcut for diff'ing two binary SHA-1 objects
If we are given two SHA-1 and asked to determine if they are different (but not _what_ differences), we know right away by comparing SHA-1. A side effect of this patch is, because large files are marked binary, diff-tree will not need to unpack them. 'diff-index --cached' will not either. But 'diff-files' still does. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Nguyễn Thái Ngọc Duy committed
Aug 16, 2014 at 10:08 UTC
1aaf69e669b7fd67073d3024b386ac25ac77d0f8
2 files changed
+23
diff.c
+13
@@ -2324,6 +2324,19 @@ static void builtin_diff(const char *name_a,
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} else if (!DIFF_OPT_TST(o, TEXT) &&
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( (!textconv_one && diff_filespec_is_binary(one)) ||
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(!textconv_two && diff_filespec_is_binary(two)) )) {
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+ if (!one->data && !two->data &&
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+ S_ISREG(one->mode) && S_ISREG(two->mode) &&
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+ !DIFF_OPT_TST(o, BINARY)) {
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+ if (!hashcmp(one->sha1, two->sha1)) {
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+ if (must_show_header)
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+ fprintf(o->file, "%s", header.buf);
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+ goto free_ab_and_return;
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+ }
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+ fprintf(o->file, "%s", header.buf);
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+ fprintf(o->file, "%sBinary files %s and %s differ\n",
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+ line_prefix, lbl[0], lbl[1]);
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+ goto free_ab_and_return;
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+ }
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if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
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die("unable to read files to diff");
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/* Quite common confusing case */
t/t1050-large.sh
+10
@@ -116,6 +116,16 @@ test_expect_success 'diff --stat' '
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git diff --stat HEAD^ HEAD
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'
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+test_expect_success 'diff' '
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+ git diff HEAD^ HEAD >actual &&
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+ grep "Binary files.*differ" actual
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+'
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+
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+test_expect_success 'diff --cached' '
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+ git diff --cached HEAD^ >actual &&
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+ grep "Binary files.*differ" actual
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+'
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+
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test_expect_success 'hash-object' '
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git hash-object large1
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'