maven won't allow cycles in the same reactor build if you are not bulging in one reactor then there may be an issue... you should raise a jira
- Stephen --- Sent from my Android phone, so random spelling mistakes, random nonsense words and other nonsense are a direct result of using swype to type on the screen On 29 Jan 2011 09:00, "Phillip Hellewell" <ssh...@gmail.com> wrote: > On Thu, Jan 27, 2011 at 1:11 PM, Ron Wheeler > <rwhee...@artifact-software.com> wrote: >> Does this matter? > > Yes. A cycle is a serious dependency problem that gone unnoticed may > be harder to fix later. > >> Is more than 1 copy of mygroup:compa:zip:vc-all:1.0.0 being included. > > Yes, in the sense that compa exists where it is checked out, and then > another (older) copy of the binaries of compa gets unpacked below > target\dependency. > >> It seems silly to make something dependent on itself and I can't imagine how > > Well obviously no one does it on purpose. > >> your would build it in the first place withyout getting an error. > > It can happen without getting an error. Just follow these steps and you'll see: > 1. Make B that doesn't depend on anything. Deploy a snapshot of B. > 2. Make A that depends on the snapshot of B . Deploy a snapshot of A. > 3. Change B to depend on the snapshot of A. Now deploy a new snapshot > of B (same version as in step 1). > > Now A depends on itself through B, but Maven gives no errors when building A. > > Now a tight cycle like this would not likely happen in real life > because it's too obvious. But with a bigger dependency tree it can > and actually DID happen to me just last week (well, not me personally; > of course it was someone else at my workplace). > >> But for mygroup:compa:pom:1.0.0, it will get 1 >> mygroup:compa:zip:vc-all:1.0.0 and that is what it needs. > > No, it was never intended for compa to depend on itself and of course > it doesn't need to depend on itself. That's ridiculous and ought to > result in an error. > > BTW, the type and classifier is kind of a red herring here. It shows > "pom" because the packaging type is pom and "zip:vc-all" because the > artifact is packaged as a zip with classifier vc-all, but that doesn't > change the fact that it is compa depending on itself. Also, this can > happen with "jar" packaging too, and then it would say "jar" in both > places (I did that test too). > >> I am missing the harm that this does since it will get detected earlier in >> the process. > > Wrong. See steps above. > > I guess I shouldn't be surprised that Maven doesn't detect a cycle as > an error. It's just funny because before we even made the decision to > go with Maven at my workplace, we had talked specifically about how a > dependency management system would automatically prevent issues like > cycles and version clashes. And we chose Maven, but Maven doesn't > detect either of these. > > The good news is Maven is flexible with plugins. We wrote a plugin to > detect version clashes, and it won't be hard to add cycle detection. > We execute this in our parent pom during the validate phase, so it > will fail when we want. > > I just can't believe no one else has run into this. > > Phillip > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@maven.apache.org > For additional commands, e-mail: users-h...@maven.apache.org >
