git can't add ignored file if GIT_ICASE_PATHSPECS=1

[Giuseppe Crino']

To reproduce, apply the attached patch and run at the project root

        cd t && ./t3700-add.sh --verbose-only=13 --debug --immediate

Relevant part of the output is

        expecting success:
                export GIT_ICASE_PATHSPECS=1 &&
                touch a.if &&
                test_must_fail git add a.?? &&
                ! (git ls-files | grep "\\.ig") &&
                (git ls-files | grep a.if)

        fatal: pathspec 'a.ig' did not match any files
        not ok 13 - error out when attempting to add ignored ones but add others
        #
        #               export GIT_ICASE_PATHSPECS=1 &&
        #               touch a.if &&
        #               test_must_fail git add a.?? &&
        #               ! (git ls-files | grep "\\.ig") &&
        #               (git ls-files | grep a.if)

As I understand this, it's a bug.

Giuseppe

diff --git a/t/t3700-add.sh b/t/t3700-add.sh
index 37729ba258..62557e6a3d 100755
--- a/t/t3700-add.sh
+++ b/t/t3700-add.sh
@@ -91,6 +91,7 @@ test_expect_success 'error out when attempting to add ignored 
ones without -f' '
 '

 test_expect_success 'error out when attempting to add ignored ones but add 
others' '
+       export GIT_ICASE_PATHSPECS=1 &&
        touch a.if &&
        test_must_fail git add a.?? &&
        ! (git ls-files | grep "\\.ig") &&