fix: Finish TTFD when binding transaction to scope

[philipphofmann]

📜 Description

Finish the TTFD span before creating a new transaction and binding it to the scope in SentryUIViewControllerPerformanceTracker when the user doesn't call reportFullyDisplayed.

💡 Motivation and Context

Fixes GH-4513

💚 How did you test it?

Unit tests and simulator.

📝 Checklist

You have to check all boxes before merging:

• I reviewed the submitted code.
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.538%. Comparing base (d9f518a) to head (402b971).
Report is 1 commits behind head on main.

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #4526       +/-   ##
=============================================
- Coverage   91.566%   91.538%   -0.029%     
=============================================
  Files          615       614        -1     
  Lines        69701     69750       +49     
  Branches     24967     24883       -84     
=============================================
+ Hits         63823     63848       +25     
- Misses        5787      5809       +22     
- Partials        91        93        +2     

Files with missing lines	Coverage Δ
Sources/Sentry/SentryPerformanceTracker.m	100.000% <100.000%> (ø)
Sources/Sentry/SentryTimeToDisplayTracker.m	100.000% <100.000%> (ø)
.../Sentry/SentryUIViewControllerPerformanceTracker.m	99.267% <100.000%> (+0.008%)	⬆️
...iewController/SentryTimeToDisplayTrackerTest.swift	100.000% <100.000%> (ø)
...entryUIViewControllerPerformanceTrackerTests.swift	99.012% <100.000%> (+0.149%)	⬆️

... and 37 files with indirect coverage changes

---

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[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1242.73 ms	1263.96 ms	21.23 ms
Size	22.30 KiB	730.72 KiB	708.41 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
879fb28	1243.18 ms	1255.98 ms	12.80 ms
98752f3	1226.18 ms	1251.38 ms	25.20 ms
e0904ef	1231.85 ms	1252.38 ms	20.53 ms
3f6c30b	1252.98 ms	1266.22 ms	13.24 ms
26530fe	1233.98 ms	1250.06 ms	16.08 ms
742d4b6	1196.56 ms	1216.54 ms	19.98 ms
8b1c6a9	1216.92 ms	1230.90 ms	13.98 ms
643853e	1225.75 ms	1247.00 ms	21.25 ms
8e76be4	1272.67 ms	1286.38 ms	13.71 ms
dacf894	1223.96 ms	1250.41 ms	26.45 ms

App size

Revision	Plain	With Sentry	Diff
879fb28	22.84 KiB	402.88 KiB	380.03 KiB
98752f3	20.76 KiB	435.09 KiB	414.33 KiB
e0904ef	21.58 KiB	614.64 KiB	593.06 KiB
3f6c30b	22.85 KiB	408.88 KiB	386.03 KiB
26530fe	21.58 KiB	714.93 KiB	693.35 KiB
742d4b6	21.58 KiB	546.20 KiB	524.62 KiB
8b1c6a9	21.58 KiB	706.97 KiB	685.38 KiB
643853e	21.58 KiB	655.73 KiB	634.15 KiB
8e76be4	20.76 KiB	427.66 KiB	406.89 KiB
dacf894	20.76 KiB	426.34 KiB	405.58 KiB

Previous results on branch: fix/finish-ttid-ttfd-spans-on-new-ui-view-controller

Startup times

Revision	Plain	With Sentry	Diff
c3b3b44	1230.88 ms	1256.09 ms	25.21 ms
976696d	1234.52 ms	1251.48 ms	16.96 ms
5ad561b	1225.22 ms	1245.67 ms	20.44 ms
c0dc9e4	1236.85 ms	1258.12 ms	21.27 ms

App size

Revision	Plain	With Sentry	Diff
c3b3b44	22.30 KiB	730.79 KiB	708.48 KiB
976696d	22.30 KiB	730.52 KiB	708.21 KiB
5ad561b	22.30 KiB	730.71 KiB	708.41 KiB
c0dc9e4	22.30 KiB	730.71 KiB	708.40 KiB

[brustolin]

LGTM

[brustolin]

BTW, I just realized a problem that goes like this:

• ViewControllerA opens, starts a HTTP request, user clicks a button and opens ViewControllerB.
• ViewControllerB starts an HTTP request.
• ViewControllerA’s HTTP request ends and SentrySDK.reportFullyDisplayed is called.

This will finish TTFD for ViewControllerB.

[philipphofmann]

BTW, I just realized a problem that goes like this:

• ViewControllerA opens, starts a HTTP request, user clicks a button and opens ViewControllerB.
• ViewControllerB starts an HTTP request.
• ViewControllerA’s HTTP request ends and SentrySDK.reportFullyDisplayed is called.

This will finish TTFD for ViewControllerB.

Do you think this PR adds this problem or that the problem still exists and needs to be addressed @brustolin?

Why do you think the ViewControllerA’s HTTP request ending does call SentrySDK.reportFullyDisplayed? Do you mean the user calls it? Before this PR calling SentrySDK.reportFullyDisplayed when being on ViewControllerB ends finishes TTFD of ViewControllerB. The same applies to this PR, but the difference now is that the TTFD of UIViewControllerA doesn't timeout any more.

[philipphofmann]

@brustolin, I now fixed GH-4513 in this PR, as I discovered that this PR on its own doesn't really make sense without fixing GH-4513. The changes required to do so weren't that big.

[brustolin]

Do you think this PR adds this problem or that the problem still exists and needs to be addressed @brustolin?

I think this PR adds this problem. Of course, by fixing another problem, we need to choose.

Why do you think the ViewControllerA’s HTTP request ending does call SentrySDK.reportFullyDisplayed? Do you mean the user calls it?

The user would call it in the code.

Before this PR calling SentrySDK.reportFullyDisplayed when being on ViewControllerB ends finishes TTFD of ViewControllerB. The same applies to this PR, but the difference now is that the TTFD of UIViewControllerA doesn't timeout any more.

🤔 I need to check If I can reproduce what Im claiming.

[philipphofmann]

I'm not sure if this PR adds the problem. Yes, please try if you can reproduce it, ideally with a test.

[brustolin]

@philipphofmann I wrote the test to reproduce what Im talking about in here

[brustolin]

LGTM