[PATCH] t7005-editor: quote filename to fix whitespace-issue

["Martin Ågren" <martin.agren@gmail.com>]

From: Alexander Pyhalov <apyhalov@gmail.com>

Commit 4362da078e (t7005-editor: get rid of the SPACES_IN_FILENAMES
prereq, 2018-05-14) removed code for detecting whether spaces in
filenames work. Since we rely on spaces throughout the test suite
("trash directory.t1234-foo"), testing whether we can use the filename
"e space.sh" was redundant and unnecessary.

In simplifying the code, though, this introduced a regression around how
spaces are handled, not in the /name/ of the editor script, but /in/ the
script itself. The script just does `echo space >$1`, where $1 is for
example "/foo/t/trash directory.t7005-editor/.git/COMMIT_EDITMSG".

With most shells, or with Bash in posix mode, $1 will not be subjected
to field splitting. But if we invoke Bash directly, which will happen if
we build Git with SHELL_PATH=/bin/bash, it will detect and complain
about an "ambiguous redirect". More details can be found in [1], thanks
to SZEDER Gábor.

Make sure that the editor script quotes "$1" to remove the ambiguity.

[1] https://public-inbox.org/git/20180926121107.GH27036@localhost/

Signed-off-by: Alexander Pyhalov <apyhalov@gmail.com>
Commit-message-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
---
 SZEDER wrote:
 > Let me put on my POSIX-lawyer hat for a moment to explain this :)

 Thanks for an excellent explanation.

 > Sidenote: this test should use the write_script helper to create this
 > editor script.

 Yes. I've punted on that for now.

 Here's my updated commit message as part of a proper patch. Thanks
 Alexander for the analysis and the diff, and thanks Eric and SZEDER for
 getting me on the right track with the commit message.

 t/t7005-editor.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/t/t7005-editor.sh b/t/t7005-editor.sh
index b2ca77b338..5fcf281dfb 100755
--- a/t/t7005-editor.sh
+++ b/t/t7005-editor.sh
@@ -112,7 +112,7 @@ do
 done
 
 test_expect_success 'editor with a space' '
-	echo "echo space >\$1" >"e space.sh" &&
+	echo "echo space >\"\$1\"" >"e space.sh" &&
 	chmod a+x "e space.sh" &&
 	GIT_EDITOR="./e\ space.sh" git commit --amend &&
 	test space = "$(git show -s --pretty=format:%s)"
-- 
2.19.0.216.g2d3b1c576c