Bugzilla – Full Text Bug Listing
| Summary: | cryptic error message if multiple reactor modules in the same baseDir | ||
|---|---|---|---|
| Product: | z_Archived | Reporter: | Stephan Herrmann <stephan.herrmann> |
| Component: | Tycho | Assignee: | Jan Sievers <jan.sievers> |
| Status: | RESOLVED FIXED | QA Contact: | |
| Severity: | normal | ||
| Priority: | P3 | CC: | igor, jan.sievers |
| Version: | unspecified | ||
| Target Milestone: | --- | ||
| Hardware: | PC | ||
| OS: | Linux | ||
| Whiteboard: | |||
|
Description
Stephan Herrmann
Can you please try Tycho 0.14.0-SNAPSHOT? This NPE is almost certainly caused by a problem with project configuration and 0.14 should provide better diagnostic messages. If this does not help identify the problem, please provide complete standalone sample project that demonstrates the problem. (In reply to comment #1) > Can you please try Tycho 0.14.0-SNAPSHOT? How? All I get is: Unresolveable build extension: Plugin org.eclipse.tycho:tycho-maven-plugin:0.14.0-SNAPSHOT or one of its dependencies could not be resolved: Could not find artifact org.eclipse.tycho:tycho-maven-plugin:jar:0.14.0-SNAPSHOT > This NPE is almost certainly caused > by a problem with project configuration and 0.14 should provide better > diagnostic messages. If this does not help identify the problem, please provide > complete standalone sample project that demonstrates the problem. A link to the example was provided in comment 0. Anything unclear in the steps to reproduce? (In reply to comment #2) > (In reply to comment #1) > > Can you please try Tycho 0.14.0-SNAPSHOT? > > How? > > All I get is: > Unresolveable build extension: Plugin > org.eclipse.tycho:tycho-maven-plugin:0.14.0-SNAPSHOT or one of its dependencies > could not be resolved: Could not find artifact > org.eclipse.tycho:tycho-maven-plugin:jar:0.14.0-SNAPSHOT Add this snippet to you (parent) pom.xml files <pluginRepositories> <pluginRepository> <id>tycho-snapshots</id> <url>https://oss.sonatype.org/content/groups/public/</url> </pluginRepository> </pluginRepositories> > > > This NPE is almost certainly caused > > by a problem with project configuration and 0.14 should provide better > > diagnostic messages. If this does not help identify the problem, please provide > > complete standalone sample project that demonstrates the problem. > > A link to the example was provided in comment 0. > Anything unclear in the steps to reproduce? Can you provide ready to use example that does not require modifications to pom.xml in order to reproduce the problem? (In reply to comment #3) > (In reply to comment #2) > > (In reply to comment #1) > > > Can you please try Tycho 0.14.0-SNAPSHOT? > > > > How? > > > [...] > > Add this snippet to you (parent) pom.xml files > > <pluginRepositories> > <pluginRepository> > <id>tycho-snapshots</id> > <url>https://oss.sonatype.org/content/groups/public/</url> > </pluginRepository> > </pluginRepositories> OK, that helps, but unfortunately it doesn't give a better error message. Only, it reminds me, that the pom mentions a version of fornax-oaw-m2-plugin that is no longer available in the snapshot repo. I changed it to 3.3.1-SNAPSHOT, but that's only a side issue here. > > A link to the example was provided in comment 0. > > Anything unclear in the steps to reproduce? > > Can you provide ready to use example that does not require modifications to > pom.xml in order to reproduce the problem? Actually, I can't. I didn't author the example and it being just a hello-world example it doesn't have a proper license statement. By attaching it to this bug I would wrongly claim that I have the right to publish. This doesn't preclude anybody from using the example for debugging etc, but, e.g., you couldn't check it into your source repo (e.g., as a test case). However, I have full confidence that you can make the few changes to this simple hello-world style pom: - change version and groupId of tycho (this is the subject of the bug) - adjust the version of fornax-oaw-m2-plugin (see above - not needed to exhibit the bug in 0.13.0) I also have some good news for you: from trial-and-error I can narrow down the original bug: The example contains the following line in its pom: <module>./pom-grammar.xml</module> when I change the directory layout so that parent and module are in distinct directories, the NPE doesn't occur. Note, that earlier versions like 0.9.0 had no problem with the directory layout. After changing the directory layout the example works as expected in 0.14.0-SNAPSHOT, but in 0.13.0 a new problem arises: the fornax plugin triggers a ClassNotFoundException, that is not raised by either older nor newer versions. Which leads me to my last question: where could I learn about the planned release date for 0.14.0? The canonical project plan URL http://www.eclipse.org/projects/project-plan.php?projectid=technology.tycho shows in interesting message :) (In reply to comment #4) > > Which leads me to my last question: where could I learn about the > planned release date for 0.14.0? The canonical project plan URL > http://www.eclipse.org/projects/project-plan.php?projectid=technology.tycho > shows in interesting message :) There is currently no specific schedule for 0.14.0 release. (In reply to comment #4) > I also have some good news for you: from trial-and-error I can narrow > down the original bug: > The example contains the following line in its pom: > <module>./pom-grammar.xml</module> I am not aware that specifying non-directories as modules is officially supported by maven, see [1]: "An pom packaged project may aggregate the build of a set of projects by listing them as modules, which are relative directories to those projects." IIRC Tycho internally keeps track of reactor modules using the module directory as unique handle, so in this case the handle is not unique anymore. This may appear semi-sane for your scenario (packaging type pom and eclipse-plugin in the same directory with different pom file names), but e.g. two modules of packaging type eclipse-plugin in the same directory won't work because META-INF/MANIFEST.MF is always expected relative to the module directory. If this is true, I would treat this as WONT_FIX and recommend to change the directory layout so that parent and module are in distinct directories as you already proposed. We may invest though to detect this scenario and throw a more sensible error message. [1] http://maven.apache.org/pom.html#Aggregation (In reply to comment #6) > I am not aware that specifying non-directories as modules is officially > supported by maven, see [1]: > > "An pom packaged project may aggregate the build of a set of projects by > listing them as modules, which are relative directories to those projects." I wasn't aware of that, and obviously the author of the example wasn't either. The interesting part is that maven *does* support this setting (referring to a module by its pom). And so did tycho versions < 0.13.0. On this background, fixing the tool to implement the specified semantics cuts both ways: the tool will be "more correct" but it will break existing software out there. The former is a good thing the latter can be expensive for the business. Of course each tool provider has to balance this conflict according to his own judgment (and communicate this decision to the users :) ). > We may invest though to detect this scenario and throw a more sensible error > message. I'd appreciate -- an NPE is never a good error message. Resolving this bug by an instructive error message sounds fair to me. (In reply to comment #7) > The interesting part is that maven *does* support this setting > (referring to a module by its pom). referring to a module by its pom is supported. multiple modules in the same baseDir are not supported. proposed change https://git.eclipse.org/r/#/c/6114/ validates this. (In reply to comment #8) > (In reply to comment #7) > > The interesting part is that maven *does* support this setting > > (referring to a module by its pom). > > referring to a module by its pom is supported. > > multiple modules in the same baseDir are not supported. thanks for clarifying! |