YANG must statement using contains

[yfherzog]

Hi,

I have this must statement which I want to use to check if a leaf-list contains a certain value:

must "contains(route-target, '15525')";

In the xpath trace I see this:

18-Jun-2019::13:38:17.870 evaluating: /vrf:vrf[device='xr-1'][vrf-name='foo']/ipv4/imports: contains(string(route-target), '15525')
18-Jun-2019::13:38:17.871 get_elem(/vrf:vrf[device='xr-1'][vrf-name='foo']/ipv4/imports/route-target) = 12:34 15525:246 23:45
18-Jun-2019::13:38:17.871 result: /vrf:vrf[device='xr-1'][vrf-name='foo']/ipv4/imports: false

I'm trying to figure out if I'm doing something wrong.

As sanity check, I tested this statement:

must "starts-with(route-target, '12:34')";

This one works as expected.

So, for some reason, I'm unable to use the contains function, but some other functions are working as I'd expect.

Any thoughts?

Thanks!

[mvolf · Accepted solution]

contains() evaluates its argument as strings; route-target is a leaf-list I suppose, i.e. it returns a node-set, and a string evaluation of a node-set is the string value of its first node. You may want something like this instead:

must "route-target[contains(., '15525')]";

[yfherzog]

That did it!

Thank you very much!

Would you mind describing the statement in words?

How come '.' is pointing where it does?

What does the statement returns? A Boolean value? The node itself?

Thanks again!

[mvolf]

It returns a node-set which is then converted to boolean - non-empty set to true, empty to false. The result can be described as all instances of route-target such that ., the instance itself, as a string contains '15525'.

[yfherzog]

Thank you for the explanation!