Merge branch 'jk/xdiff-clamp-funcname-context-index' into maint
The internal diff machinery can be made to read out of bounds while
looking for --funcion-context line in a corner case, which has been
corrected.
* jk/xdiff-clamp-funcname-context-index:
xdiff: clamp function context indices in post-image
diff --git a/t/t4015-diff-whitespace.sh b/t/t4015-diff-whitespace.sh
index ab4670d..6b087df 100755
--- a/t/t4015-diff-whitespace.sh
+++ b/t/t4015-diff-whitespace.sh
@@ -2008,4 +2008,26 @@
test_cmp expected actual
'
+# Note that the "6" in the expected hunk header below is funny, since we only
+# show 5 lines (the missing one was blank and thus ignored). This is how
+# --ignore-blank-lines behaves even without --function-context, and this test
+# is just checking the interaction of the two features. Don't take it as an
+# endorsement of that output.
+test_expect_success 'combine --ignore-blank-lines with --function-context' '
+ test_write_lines 1 "" 2 3 4 5 >a &&
+ test_write_lines 1 2 3 4 >b &&
+ test_must_fail git diff --no-index \
+ --ignore-blank-lines --function-context a b >actual.raw &&
+ sed -n "/@@/,\$p" <actual.raw >actual &&
+ cat <<-\EOF >expect &&
+ @@ -1,6 +1,4 @@
+ 1
+ 2
+ 3
+ 4
+ -5
+ EOF
+ test_cmp expect actual
+'
+
test_done
diff --git a/xdiff/xemit.c b/xdiff/xemit.c
index 7778dc2..30713ae 100644
--- a/xdiff/xemit.c
+++ b/xdiff/xemit.c
@@ -210,7 +210,7 @@
if (fs1 < 0)
fs1 = 0;
if (fs1 < s1) {
- s2 -= s1 - fs1;
+ s2 = XDL_MAX(s2 - (s1 - fs1), 0);
s1 = fs1;
}
}
@@ -232,7 +232,7 @@
if (fe1 < 0)
fe1 = xe->xdf1.nrec;
if (fe1 > e1) {
- e2 += fe1 - e1;
+ e2 = XDL_MIN(e2 + (fe1 - e1), xe->xdf2.nrec);
e1 = fe1;
}
