Bug 758427

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In a systemd unit template file (a file like /etc/systemd/system/blah@.service) at least the fields "ConditionPathExists" and "Requires" have trouble handling %I.

Reproducible: Always

Steps to Reproduce:
Here are two service files which I created in order to autostart an iaxmodem whenever a corresponding faxgetty gets started:

================= iaxmodem@.service ================
[Unit]
Description = IAXmodem for /dev/%I
ConditionPathExists = /etc/iaxmodem/%I
Requires = asterisk.service
After = asterisk.service

[Service]
Type = simple
ExecStart = /usr/sbin/iaxmodem %I
====================================================

============= faxgetty4ttyiax@.service =============
[Unit]
Description = HylaFAX faxgetty at /dev/%I
ConditionPathExists = /var/spool/fax/etc/config.%I
ConditionPathExists = /etc/iaxmodem/%I
Requires = iaxmodem@%I.service

[Service]
Type = simple
Restart = on-success
ExecStart = /usr/lib/fax/faxgetty /dev/%I
====================================================

The files /etc/iaxmodem/ttyiax1 and /var/spool/fax/etc/config.ttyiax1 exist.
Actual Results:  
$ systemctl start faxgetty4ttyiax@ttyiax1.service
produces
> systemd[1]: Failed to add dependency on iaxmodem@%I.service, ignoring: Invalid argument
in /var/log/messages and
> start condition failed at ...
in the status output of
$ systemctl status faxgetty4ttyiax@ttyiax1.service

Expected Results:  
$ systemctl start faxgetty4ttyiax@ttyiax1.service
should start a faxgetty instance and pull in the corresponding iaxmodem service.

If my understanding of the templating mechanism (on the man page of systemd.unit) is correct, such a construction is supposed to work.
If it is intentional that the %-specifiers don't get resolved, please consider this bug report a feature request.