Description:

When using the kubernetes plugin and executing a script inside of a container block, environment variables that contain a literal dollar in their value appear to have an extra dollar added before the existing literal dollar.

E.g. if the environment and container block were:

environment {
  FOO="\$BAH"
}
steps {
  container('busybox') {
    sh 'echo "FOO=$FOO"'
  }
}

then the console output shows:

[Pipeline] withEnv
[Pipeline] {
[Pipeline] container
[Pipeline] {
[Pipeline] sh
+ echo 'FOO=$$BAH'
FOO=$$BAH
[Pipeline] }
[Pipeline] // container
[Pipeline] }
[Pipeline] // withEnv

Expected behaviour:

the value of the environment variable is not altered when referenced inside the container block.

Work around:

None that I've found yet.

Other info:

Some other permutations I've tried:

• When the script is executed outside of the container block, the environment variable value is unchanged.
• When the value of the environment variable contains a literal dollar not at the start of the string, the value is still changed.  E.g. A value of "Something \$BAH" echoes as "Something $$BAH"

Environment where the bug was seen:

Jenkins: CloudBees Core Managed Master 2.204.3.2-rolling
Kubernetes plugin: 1.23.1