When troubleshooting a pipeline for a test, it can be useful to print
the input out without necessarily preventing the pipeline to work.
The Tee gadget is exactly made for this purpose, the input of the Tee is
printed out through `t.Log`, and the input is forwarded to the next step
in the pipeline.
When the PACKER_PLUGIN_PATH envvar is defined in the environment, Packer
uses it as the source of truth for the directories in which to look for
plugins to load.
Previously, we used to support multiple directories separated by the
OS-specific path separator (i.e. : on UNIX, ; on Windows).
Since this changed, and Packer returns an error to the user, we make
sure that this is well-documented and tested through this extra test.
The IntCompare checker converts the input string into an int through
strconv.Atoi, which fails when the string isn't valid base 10. This
definition of "valid" also excludes whitespace, which occurs often
through piping gadgets, but shouldn't be a reason to fail that check, so
we trim the whitespace from the input string.
Lucas Bajolet
Wilken Rivera