"API incompatibility" on model.core

[kaikreuzer]

It seems that some update on Eclipse dependencies causes our build to fail (see https://ci.eclipse.org/smarthome/job/SmartHomeDistribution-Nightly/3198/console):

[ERROR] Failed to execute goal org.eclipse.xtend:xtend-maven-plugin:2.14.0:compile (default) on project org.eclipse.smarthome.model.core: Execution default of goal org.eclipse.xtend:xtend-maven-plugin:2.14.0:compile failed: An API incompatibility was encountered while executing org.eclipse.xtend:xtend-maven-plugin:2.14.0:compile: java.lang.NoSuchMethodError: org.eclipse.jdt.internal.compiler.batch.FileSystem.getClasspath(Ljava/lang/String;Ljava/lang/String;ZLorg/eclipse/jdt/internal/compiler/env/AccessRuleSet;Ljava/lang/String;Ljava/util/Map;)Lorg/eclipse/jdt/internal/compiler/batch/FileSystem$Classpath;

[kaikreuzer]

Strangely, a local build of the latest master works for me. Where could be the difference for the Jenkins build? https://github.com/eclipse/xtext-xtend/issues/493 looks like this problem.

[kaikreuzer]

As I cannot reproduce it locally, I can only guess how to fix it - first try is #6718...

[MHerbst]

I remember a similar strange problems in our company after we changed the Tycho version to 1.2.0. Maybe it could help to go back to 1.1.0.

[kaikreuzer]

@MHerbst I ran https://ci.eclipse.org/smarthome/job/SmartHomeDistribution-Nightly/3200/ with Tycho 1.1.0, didn't help either :-(

[MHerbst]

@kaikreuzer I have found this issue in the XTEXT Repo: https://github.com/eclipse/xtext/issues/1373#issuecomment-449001543 According to this issue it helps to pin org.eclipse.emf.codegen to 2.11.0.

[kaikreuzer]

Thanks @MHerbst, I have created https://github.com/eclipse/smarthome/pull/6722.

[kaikreuzer]

Finally, the build is green again!