[tycho-user] Update site does not contain new plugin of patch feature

[Hemal Pandya <hemal.pandya@xxxxxxxxx>]

We use patch feature for patching installation with new versions of
plugins. This is the first time when the feature contains a new plugin
that did not exist in the previous version of the (full) feature.

To take example, consider that Feature F in version 1.0 contains two
plugins P1 and P2 and in version 1.1, it contains three -- P1, P2 and
P3.We use the id F.patch_1_1 for the 1.1 patch feature for F. So:

F:1.0 contains P1:1.0, P2:1.0
F:1.1 contains P1:1.1, P2:1.1, P3:1.1
F.patch_1_1:1.1 contains P1:1.1, P2:1.1, P3:1.1

In the eclipse-feature build, the generated target/feature.xml lists
all three plugins, and their versions have been changed from
1.1.qualifier to 1.1.nnn1, where n1 is the timestamp.

In the eclipse-repository build, the generated feature jar
(target/repository/F.patch_1_1.1.1.n2.jar --- n2 being a later
timestamp than n1) contains the identical feature.xml. But actual
plugin jar is missing from target/repository/plugins directory. This
is the only plugin missing, all the others are present.

During the update-site build, the following a warning is logged from
Mirror tool:
[WARNING] Mirror tool: "Problems resolving provisioning plan.":
["Unable to satisfy dependency from F.patch_1_1.feature.group 1.1.n2
to P1  [1.1.n1]."]

Just before that warning
tycho-p2-repository-plugin:0.18.1:assemble-repository logs warnings as
follows. Note that it lists the timestamps of the feature, not the
plugins.
[WARNING] The following locally built units have been used to resolve
project dependencies:
[WARNING]   configure.P1/1.1.N2
[WARNING]   configure.P2/1.1.N2
[WARNING]   F.patch_1_1.feature.group/1.1N2
[WARNING]   configure.P3/1.1.N2

I know this is not a lot of information. I will be happy to provide
any additional information that might be relevant.

Any help, pointers or work-arounds are much appreciated.