TYPO3 Flow Base Distribution - Bug #41843: Composer and rename issues (umbrella issue)
Check for duplicate PSR-0 autoload namespaces
Currently, if two packages define the same PSR-0 autoload namespace in their composer.json, it goes unnoticed by the package management.
For example, if someone (let's say, me) just copies a composer manifest from a different package (TYPO3.Flow) and forgets to update the "autoload" part, the new package will end up in a directory "TYPO3.Flow" too. The symptom then is that no Flow classes can be found by the autoloader, because it looks into the other package directory.
While generating PackageStates.php (or somewhere in that area) we should check for duplicate PSR-0 namespaces and issue a warning.