[Bug]: DefaultMigrationService does not null-check fixer.update() result

[Splatcrafter]

AI REVIEWED

Module: spring-boot-starter
File: spring/service/DefaultMigrationService.java (~line 425)
Severity: Medium

Summary

The result from fixer.update() is wrapped in MigrationResult.success() without null-checking. A faulty DataFixer implementation returning null would cause NPE.

Suggested Fix

Dynamic<?> result = fixer.update(type, data, from, to);
if (result == null) {
    return MigrationResult.failure(from, to, new IllegalStateException("DataFixer returned null"));
}
return MigrationResult.success(result, from, to);