[MNG-8050] emit warn in case of repo id clashes between settings and POM

[kwin]

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[cstamas]

@gnodet ?

[kwin]

If there are no concerns I am gonna merge end of next week @gnodet.

[gnodet]

@kwin Should we check that the repositories are actually not the same ? What's the problem is they point to the same repo ? If the user simply wants to override the policy in the settings ?

BTW, I think the mapping from an id to a repository URI should actually be defined in the local repository. I think two projects using the same id but pointing to different repositories might be problematic too.

[kwin]

@gnodet I now only emit warning if the URLs differ (https://github.com/apache/maven/commit/cd7aba6af6ff80a394e12b975a293fa07cb813c9)

I think the mapping from an id to a repository URI should actually be defined in the local repository

Not sure how this can ever be achieved. I still want to be able to clone arbitrary projects and build it immediately without needing to tweak either my settings.xml or some other Maven configuration file.

[gnodet]

@gnodet I now only emit warning if the URLs differ (cd7aba6)

I think the mapping from an id to a repository URI should actually be defined in the local repository

Not sure how this can ever be achieved. I still want to be able to clone arbitrary projects and build it immediately without needing to tweak either my settings.xml or some other Maven configuration file.

@cstamas can the resolver provide any help here ?

[cstamas]

Sadly nope.

IMHO the best we can do is to accept the facts:

• repository ID is the "key" (so assume URL is "just" an attribute) and limit ourselves onto ID clash checking
• maybe as improvement, warn (optionally fail) the build, if there are two different IDs with same URLs?
• cases when same ID may be used for different reposes (or when different IDs are used for same repository) mostly stands for us, people that check out various project, having various "repo naming conventions" (as for example, ideally within one company or even forge, this should be unified) is we simply cannot handle.

[kwin]

@gnodet I think we should also warn if the URL is equal but the <enabled> flags for either <release> or <snapshot> differ. Otherwise this might lead to subtle issues which are hard to debug.

[kwin]

I think we should also warn if the URL is equal but the flags for either or differ. Otherwise this might lead to subtle issues which are hard to debug.

I decided to ignore those subtle differences for now.