Add test coverage and fix handling for zero value progression calculations

[Copilot]

Adds comprehensive test cases for progression calculations when endValue is 0, covering normal stats, quotient stats (fkdr/kdr), and stars/experience. Also fixes the implementation to properly handle zero values with appropriate milestones.

Changes

• Linear stats: 45 test cases covering all 9 stats × 5 gamemodes

  • Tests the case where stats remain at 0 (no progress)
  • Milestone is set to 1 when current value is 0
  • Days until milestone is Infinity when there's no progress

• Quotient stats: 10 test cases for fkdr/kdr × 5 gamemodes

  • Tests when both dividend and divisor are 0 (no progress)
  • Milestone is set to 1 with sessionQuotient of 0

• Stars/Experience: 10 test cases × 5 gamemodes

  • Tests when experience is 0 and remains at 0
  • Experience milestone is 1, stars milestone is 100 (next prestige)
  • Days until milestone is Infinity with no progress

• Implementation fix: Updated progression.ts to handle endValue === 0 case

  • When endValue is 0 with no progress, returns milestone of 1 with Infinity days
  • Prevents Math.log10(0) which causes NaN values
  • "No progress" is no longer an error case, returns valid result instead

Example test structure:

await t.test("edge case - zero current value", () => {
    // Start: 0, End: 0 (no change)
    const history: History = [
        new PlayerDataBuilder(TEST_UUID, startDate)
            .withGamemodeStats(gamemode, 
                new StatsBuilder().withStat(stat, 0).build())
            .build(),
        new PlayerDataBuilder(TEST_UUID, endDate)
            .withGamemodeStats(gamemode, 
                new StatsBuilder().withStat(stat, 0).build())
            .build(),
    ];
    
    assert.deepStrictEqual(result, {
        stat, endValue: 0, progressPerDay: 0,
        nextMilestoneValue: 1, daysUntilMilestone: Infinity,
        trendingUpward: true,
        trackingDataTimeInterval: { start: startDate, end: endDate }
    });
});

Total: 65 new test cases. All 463 tests pass.

Original prompt

Add test cases to the progression tests covering the case when the current value is 0. Both for normal stats, quotient stats and stars/exp. For stars/ exp note that these cases are constructed, and new players have 500exp/1 star

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View logs

[Amund211]

Update the cases to not decrease in stats. When the end value is 0, the start value should be 0 as well. Also update the test cases to have milestone 1 when the value is 0. Then fix the implementation to handle this @copilot

[Copilot]

Update the cases to not decrease in stats. When the end value is 0, the start value should be 0 as well. Also update the test cases to have milestone 1 when the value is 0. Then fix the implementation...

Updated the test cases and implementation in commit 41a3374:

• Test cases now have both start and end values at 0 (no decrease in stats)
• When endValue is 0, milestone is set to 1 and daysUntilMilestone is Infinity
• Fixed the implementation to handle the endValue === 0 case properly
• Removed "no progress" from error cases since it now returns a valid result

All 463 tests pass.

[Amund211]

zero value tests should probably just be just a special case of the no progress cases, which should return a milestone and infinite expected time instead of a no progress error