[MDEP-651] unpack-dependencies should warn when it overrides extracted files on macos (case insensitive FS) #1082

Hasnae Rehioui opened MDEP-651 and commented

Background :

We are upgrading to a recent version of aspose-imaging and ran into an issue with our unpack-dependencies configuration when ran locally on macos

This is affecting our dev loop mostly, you can reproduce it with 

git clone https://github.com/viqueen/maven-playground
cd maven-playground
mvn test

long story short :

maven-dependency-plugin has the unpack-dependencies mojo that relies on plexus un-archiver which in a file system like mac (not case sensitive) , might end up overriding files , leading in some cases to a corrupted class path , aspose-imaging library is an example of that : it contains classes and interfaces named as follow : com.aspose.internal.imaging.gq/aq (interface) , com.aspose.internal.imaging.gq/aQ (class implementing the interface)  , notice the case sensitive naming

so on mac , the plugin will override the aq interface with the content of aQ type , leading to a NoClassDefFoundError because the file name and its content do not match

java.lang.NoClassDefFoundError: com/aspose/imaging/internal/gq/aq (wrong name: com/aspose/imaging/internal/gq/aQ)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)

Workaround :

turns out our project config no longer requires unpacking dependencies so we disabled the thing

Suggestion :

not sure this is even fixable , but would be nice to have some debug / warning logs that it is happening so developers can diagnose errors more easily; basically throw in some love onto https://github.com/viqueen/plexus-archiver/blob/master/src/main/java/org/codehaus/plexus/archiver/AbstractUnArchiver.java#L346

in our particular use case , we are consuming the plugin through https://bitbucket.org/atlassian/amps/src/903a1ce408da5b8500ed0d7e0e5701eb83d8cde4/amps-maven-plugin/src/main/java/com/atlassian/maven/plugins/amps/MavenGoals.java?at=8.0-stable&fileviewer=file-view-default#MavenGoals.java-458 , these internals are not exactly common knowledge and the logs were not helping either, devs knew it was FS related though just not clear on what triggers the problem

so optionally failing the build if/when it happens could point our devs on the right track much faster

Affects: 3.1.1

Remote Links:

• GitHub Pull Request #13