Joda-Time to Java time: Add support for Method Return Statement Migration

[amishra-u]

What's changed?

• Added support for safely migrating method return statements of the Joda type.
• Migration Safety Criteria: A method return statement is considered safe to migrate if:
  • The return statement itself can be safely migrated.
  • All invocations of the method are safe to migrate.

Key Changes:

1. Used a map of methodReferencedVars to track the referenced variables during assignment and in return expression. (A method invocation is unsafe for migration if any of referenced var is unsafe)
2. Added a safeMethodMap to track the safe methods
3. Added new test cases and updated existing ones to reflect the changes.

Not Implemented Yet:

1. Migration of class variables.

Checklist

• I've added unit tests to cover both positive and negative cases
• I've read and applied the recipe conventions and best practices
• I've used the IntelliJ IDEA auto-formatter on affected files

[timtebeek]

Great to see @amishra-u ; thanks for the continued work here. I was slightly surprised to see methods migrated that have a public modifier and Joda-Time return type, but I suppose at some point we're going to have to make some changes if folks are to migrate at all. Let's hope folks understand that this is a one time migration that is hard to make guaranteed safe.

[amishra-u]

Great to see @amishra-u ; thanks for the continued work here. I was slightly surprised to see methods migrated that have a public modifier and Joda-Time return type, but I suppose at some point we're going to have to make some changes if folks are to migrate at all. Let's hope folks understand that this is a one time migration that is hard to make guaranteed safe.

Yes, it needs to run on the entire repository at once to ensure a safe migration. I've noticed that many projects have utility methods around DateTime. If these utility methods aren't migrated, the coverage becomes minimal because Joda-Time types are tightly interconnected. For example, intervals depend on DateTime, DateTime relies on time zones, and this interconnectedness makes everything unsafe if those utility methods are not migrated