Find the culprit
Finding the one single OXP which is making your game go wrong!
Contents
Overview
In case you experience a strange situation with Oolite - and in case you want to talk to someone about this - it definitely helps others to describe not just
- the symptoms
- but also
- which Oolite version,
- which distribution and especially
- which expansions you have installed.
But you can do even more.
Here is a guide for troubleshooting, which should work if you track a problem in Oolite (core), in one expansion or in the incompatibility between several expansions. Basically it is a binary search in the installed expansions. This allows with a minimum of test cycles to span a big number of expansions. Suppose you installed all the eight hundred-odd expansions that currently are on the expansion catalog. Then only 10 tests should be sufficient to spot the one expansion causing a problem.
Algorithm
Prerequisite
- As you will be juggling a lot of expansions back and forth, find your directories where Addons and ManagedAddons are stored.
- Create a backup of these directories.
- Decide for a procedure to check for the bug. Write it down. This could be to load a savegame, fly to whatever star system, shoot a pirate and then check your cargo hold.
Once you have that, you can start the troubleshooting loop.
Validate Vanilla Oolite
First, find out if the problem occurs in the Vanilla game code. For this, remove all expansions, (for example, by restarting a new game in "Strict mode"). Perform your test.
If the problem occurs, it is in the core. Congratulations, you can file an issue in the oolite github repository.
If it doesn't, the vanilla game code is clean. Restore your expansions.
Binary Search of OXPs/OXZs
Check Partition
Create a list of all the installed expansions' names and versions - you will need this. Oolite Starter can do this easily for you.
Delete half of them (if you have an odd number of them, then it does not matter whether you delete one more or less). If no expansion is left, and you still have not found the problem check the next section.
Write down the list of those that are left.
Run Oolite and perform your test.
If the problem occurs, the installed expansions caused it. If that happened on the last one expansion, you found it! Go to the Oolite bulletin board and ask for help. Otherwise repeat the Check Partition step.
If the problem does not occur, it stems from the other half. Restore the expansions from the other half and repeat the Check Partition step.
The problem vanished
While you were troubleshooting with partitions all of a sudden the problem no longer occurred. Neither in the first half nor in the second half.
Then it is likely the problem is caused by a combination of expansions that now got split over the two halves. Cut each half into two pieces again (now you have quarters).
Now combine the first half's first half with the second half's first half. Combine the remaining two halves, hoping the problem would show up with one of them. If it does, go back to the Check Partition step.
If it still doesn't, we have to switch the strategy.
Restore the smallest combination of expansions that produces the problem.
Remove one and test again.
If the problem persists, repeat the step.
If the problem vanished, restore the deleted expansion and remove another one.
This should bring you down to the least amount of expansions that - installed together - produce a problem. With that information go to the Oolite bulletin board and ask for help.
Good luck, Commander!
Example Scenarios
Ben's problem in one expansion
https://cdn-0.plantuml.com/plantuml/png/SoWkIImgAStDuIfAJIv9p4lFILLmH68x8R6T5HAB5PISjPIGn5oGsAv8R3SajZkNGsfU2j0E0000 Ben loves playing Oolite, and over time he accumulated a couple of expansions. For brewity we just call them with one letter each.
One day Ben discovers a strange, annoying behaviour. His ship kills counter does not increase reliably when he blows up some ship. Ben has a problem in expansion C (note the asterisk), but he does not know. With no better plan in mind he finds this wiki page and starts applying the algorithm to find the culprit.
Prerequisite
Ben finds the folders for Addons in ~/Oolite/Addons and ~/Oolite/.ManagedAddons. He makes a backup copy of these folders. Also he writes down how to reproduce the bug: - Start Oolite - Load Savegame fifteen - Switch to the F5 screen and check the kill count before - Launch from the station and kill the next trader ship in the star system - Switch to the F5 screen and check the kill count after - It is expected to see the kill count increased by one
