[BUG]: VSTest@3: "Skipping coverage attachment since it is to big"

[gbtec-georgs]

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• I searched for existing GitHub issues
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Task name

VSTest@3

Task version

3.255.0

Issue Description

✅ All tests pass.
✅ Test results are published.
❌Code coverage is not published.

Diagnostic logs show message "Skipping coverage attachment since it is to big".

Note: The "to" in the message is not a typo in this bug report.

I have reduced the number of tests from initially >30k to just 25, but I still get no coverage results plus the aforementioned message.

Environment type (Please select at least one enviroment where you face this issue)

• Self-Hosted
• Microsoft Hosted
• VMSS Pool
• Container

Azure DevOps Server type

dev.azure.com (formerly visualstudio.com)

Azure DevOps Server Version (if applicable)

No response

Operation system

Windows Server 2022

Relevant log output

2025-06-14T12:43:48.7175961Z Publishing Attachments: 2
2025-06-14T12:43:48.7354768Z ##[debug]Entering CreateTestRunAttachmentsAsync
2025-06-14T12:43:48.7567093Z ##[debug]Leaving CreateTestRunAttachmentsAsync
2025-06-14T12:43:48.7586124Z ##[debug]Uploading test run attachements individually
2025-06-14T12:43:48.7676734Z ##[debug]Entering UploadTestRunLogAsync
2025-06-14T12:43:48.8495833Z ##[debug]Skipping coverage attachment since it is to big 👈👀
2025-06-14T12:43:48.9790481Z ##[debug]Blob name: GeneralAttachment/VssAdministrator_fv-az596-220_2025-06-14_14_29_28.trx .
2025-06-14T12:43:50.1085596Z ##[debug]File uploaded successsfully on LogStore VssAdministrator_fv-az596-220_2025-06-14_14_29_28.trx
2025-06-14T12:43:50.1106289Z ##[debug]Completed PublishTestResult

Full task logs with system.debug enabled

 sorry, can't share this 

Repro steps

[gbtec-georgs]

I can add the following insight:

Once I reduce the number of covered DLLs in .runsettings (using <ModulePaths/><Include><ModulePath>A single dll</ModulePath></Include></ModulePaths>) the coverage is published correctly.

Note: The original module filter was setup to include all DLLs of our organization, using a filter like this: <ModulePaths><Include><ModulePath>.*\\MyOrg\.[^\\]+\.dll$</ModulePath></Include></ModulePaths>.