[yocto] Excluding ptest packages from image build

[Erik Nellessen]

I would like to exclude some ptest packages from an image build.

To include ptest packages in general, my image recipe contains the 
following line:
IMAGE_FEATURES_append = " ptest-pkgs"

As a first step, I tried to exclude the acl-ptest package. To do so, I 
added the following to my image recipe:
PACKAGE_EXCLUDE_COMPLEMENTARY = "acl-ptest"

I thought that this would exclude the acl-ptest package as described in 
the project reference: 
https://www.yoctoproject.org/docs/2.4.2/ref-manual/ref-manual.html#var-PACKAGE_EXCLUDE_COMPLEMENTARY
"Prevents specific packages from being installed when you are installing 
complementary packages.

You might find that you want to prevent installing certain packages when 
you are installing complementary packages. For example, if you are using 
IMAGE_FEATURES to install dev-pkgs, you might not want to install all 
packages from a particular multilib. If you find yourself in this 
situation, you can use the PACKAGE_EXCLUDE_COMPLEMENTARY variable to 
specify regular expressions to match the packages you want to exclude."

Anyhow this did not result in an image without the acl-ptest package, as 
I could validate by having a look at the image's manifest file.

When I changed the image recipe to contain the regular expression "acl", i.e
PACKAGE_EXCLUDE_COMPLEMENTARY = "acl"
all three acl packages (acl, acl-lic, acl-ptest) were excluded from the 
image.

And to really start the confusion, when changed the regular expression 
to "acl.", i.e.
PACKAGE_EXCLUDE_COMPLEMENTARY = "acl."
all three packages were also excluded.

Now I am really confused. My expectation was that "acl-ptest" and "acl" 
would match the acl-ptest package name and "acl." would not match the 
acl package name.

Does anybody see what I am missing here?

Thanks in advance,
Erik