git/t/t4038-diff-combined.sh
Thomas Rast 2179870803 combined diff: correctly handle truncated file
Consider an evil merge of two commits A and B, both of which have a
file 'foo', but the merge result does not have that file.

The combined-diff code learned in 4462731 (combine-diff: do not punt
on removed or added files., 2006-02-06) to concisely show only the
removal, since that is the evil part and the previous contents are
presumably uninteresting.

However, to diagnose an empty merge result, it overloaded the variable
that holds the file's length.  This means that the check also triggers
for truncated files.  Consequently, such files were not shown in the
diff at all despite the merge being clearly evil.

Fix this by adding a new variable that distinguishes whether the file
was deleted (which is the case 4462731 handled) or truncated.  In the
truncated case, we show the full combined diff again, which is rather
spammy but at least does not hide the evilness.

Reported-by: David Martínez Martí <desarrollo@gestiweb.com>
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-04-17 10:23:59 -07:00

93 lines
1.7 KiB
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Executable File

#!/bin/sh
test_description='combined diff'
. ./test-lib.sh
setup_helper () {
one=$1 branch=$2 side=$3 &&
git branch $side $branch &&
for l in $one two three fyra
do
echo $l
done >file &&
git add file &&
test_tick &&
git commit -m $branch &&
git checkout $side &&
for l in $one two three quatro
do
echo $l
done >file &&
git add file &&
test_tick &&
git commit -m $side &&
test_must_fail git merge $branch &&
for l in $one three four
do
echo $l
done >file &&
git add file &&
test_tick &&
git commit -m "merge $branch into $side"
}
verify_helper () {
it=$1 &&
# Ignore lines that were removed only from the other parent
sed -e '
1,/^@@@/d
/^ -/d
s/^\(.\)./\1/
' "$it" >"$it.actual.1" &&
sed -e '
1,/^@@@/d
/^- /d
s/^.\(.\)/\1/
' "$it" >"$it.actual.2" &&
git diff "$it^" "$it" -- | sed -e '1,/^@@/d' >"$it.expect.1" &&
test_cmp "$it.expect.1" "$it.actual.1" &&
git diff "$it^2" "$it" -- | sed -e '1,/^@@/d' >"$it.expect.2" &&
test_cmp "$it.expect.2" "$it.actual.2"
}
test_expect_success setup '
>file &&
git add file &&
test_tick &&
git commit -m initial &&
git branch withone &&
git branch sansone &&
git checkout withone &&
setup_helper one withone sidewithone &&
git checkout sansone &&
setup_helper "" sansone sidesansone
'
test_expect_success 'check combined output (1)' '
git show sidewithone -- >sidewithone &&
verify_helper sidewithone
'
test_expect_success 'check combined output (2)' '
git show sidesansone -- >sidesansone &&
verify_helper sidesansone
'
test_expect_success 'diagnose truncated file' '
>file &&
git add file &&
git commit --amend -C HEAD &&
git show >out &&
grep "diff --cc file" out
'
test_done