Skip sub-projects of deselected projects

[don-vip]

From documentation:

Since 3.10.1, "deselected" projects (mvn -pl !...) that contain changes will not be built, but their up- and downstream projects will be built (if not also deselected).

The behaviour concerning sub-modules is not specified. In this example:

A

• B < I want to ignore all projects under B
  • C
  • D < a file is changed here
  • E, F, G... Many many more sub-projects

When I run mvn -pl '!:B' -Dgib.disable=true, Maven reactor excludes all modules under B.

But when I run mvn -pl '!:B', gib sees that D is changed and builds it.

Is it a bug or intended behaviour? If that's intended it would be great to have a configuration option to change this behaviour.

[famod]

Thanks for reporting this!

In your example, are C, D etc. referencing B as their parent or not? This makes a difference because Maven considers C a downstream module of B when there is such a parent relationship.

[famod]

I tested this briefly and when there is such a parent relation, mvn -pl '!:X' does not exclude the sub-modules of X.

PS: I haven't tested the non-parent variant yet.

[don-vip]

I tested this briefly and when there is such a parent relation, mvn -pl '!:X' does not exclude the sub-modules of X.

I am so sorry, you're right. During my manual tests I forgot to add the required profiles of the sub-modules... I don't know if there is a "Maven way" to achieve what I want (build everything except B and its sub-modules, without having to list all of them)

[famod]

No worries!

Maven 4 will actually make -pl recursive, so that -pl B will build B and all its sub-modules and -pl !B will neither build B nor its sub-modules.
The old behavior can be brought back with -N -pl ....

The problem with a custom implementation is that all upstream/downstream calculation in GIB is currently based on Maven core DependencyGraph (well, except a part of the BOM support).
I'll leave this open for now and think about this a bit more...

[famod]

@don-vip In case there is also a module X under A (sibling of B), that depends on B or any of its sub-modules: Would you expect GIB to build X in case B or any of its sub-modules is changed but B is excluded (and its sub-modules)?

[don-vip]

Good question. It doesn't make sense in my project. If it was the case I think I would exclude X as well. So I don't know what would be the best choice for GIB behaviour here.

[famod]

Well, not building X in that case is the complicated part because GIB would need to evaluate all of its upstream modules to figure out whether is should be excluded or not. A graph analysis so to say, which can be rather slow for big repos if not done cleverly.
Just excluding B and its sub-modules should be the way easier part.

I think I'll have a look at how Maven 4 alpha behaves but I suppose the new recursive behavior of -pl !... will not exclude dependencies...

[famod]

Status: I didn't have the time to look into this in detail for 3.14.0 (which I will release today) but I think we'll need a new GIB property for this, e.g. -Dgib.excludeDownstreamModules=B or similar, probably with wildcard support.