"For loop" bash command does not execute in Jenkins build - jenkins

Question

I try to execute such a scenery via Jenkins "execute shell" build step:
rm -r -f _dpatch;
mkdir _dpatch;
mkdir _dpatch/deploy;
from_revision='HEAD';
to_revision='2766920';
git diff --name-only $from_revision $to_revision > "_dpatch/deploy/files.txt";
for file in $(<"_dpatch/deploy/files.txt"); do cp --parents "$file" "_dpatch"; done;
whoami
Build ends successfully with console output:
[Deploy to production] $ /bin/sh -xe /tmp/hudson8315034696077699718.sh
+ rm -r -f _dpatch
+ mkdir _dpatch
+ mkdir _dpatch/deploy
+ from_revision=HEAD
+ to_revision=2766920
+ git diff --name-only HEAD 2766920
+
+ whoami
jenkins
Finished: SUCCESS
The problem is line "for file in" is just ignored, I do not understand why.
Content of files.txt is not empty and looks like this:
addons/tiny_mce/plugins/image/plugin.min.org.js
addons/webrtc/adapter-latest.js
templates/standard/style/review.css
More over, when I execute via ssh the same script in the same jenkins workspace folder under the same user (jenkins) - "for file in" line executes normally and creates files in "_dpatch" subfolder as it should.
My environment:
Debian 8,
Jenkins 2.45
Thanks

Answer 1

Possibly your /bin/sh is a POSIX bourne shell. It think that the $(< construct is a bash-ism, so it will not work with /bin/sh.
Try to replace
$(<"_dpatch/deploy/files.txt")
with
$(cat "_dpatch/deploy/files.txt")
Alternatively, prepend your build step with #!/bin/bash.
If your login shell is bash, then this also explains why everything works fine via ssh.

Answer 2

Try substituting for with while loop. And also add some more logging
rm -r -f _dpatch;
mkdir _dpatch;
mkdir _dpatch/deploy;
from_revision='HEAD';
to_revision='2766920';
git diff --name-only $from_revision $to_revision > "_dpatch/deploy/files.txt" && echo "git diff finished"
while IFS= read -r line; do
echo $line
cp --parent $line $_dpatch
done < _dpatch/deploy/files.txt
whoami