[ci] Fix internal pipeline OfficialBuildId format

[PureWeen]

Note

Are you waiting for the changes in this PR to be merged?
It would be very helpful if you could test the resulting artifacts from this PR and let us know in a comment if this change resolves your issue. Thank you!

Description

The dotnet-maui-build internal pipeline (definition 1536) has been failing on every single build since ~Jan 27 (~5+ weeks) because BUILD.BUILDNUMBER changed format to 10.0.50+azdo.XXXXX.

Arcade's Version.BeforeCommonTargets.targets tries to do arithmetic on OfficialBuildId using [MSBuild]::Add/Multiply/Subtract, but the + character in the new format causes MSB4186: Invalid static method invocation syntax.

Fix

Change the internal pipeline's _OfficialBuildIdArgs from $(BUILD.BUILDNUMBER) to $(_BuildOfficialId) (the yyyyMMdd.counter format already used by all other pipeline configurations).

Impact

• Internal (dotnet-maui-build): Fixed — uses _BuildOfficialId (yyyyMMdd.counter)
• Public (maui-pr): Unchanged — already uses _BuildOfficialId
• PR builds: Unchanged — already uses _BuildOfficialId
• Publishing and signing args are untouched

[github-actions]

🚀 Dogfood this PR with:

⚠️ WARNING: Do not do this without first carefully reviewing the code of this PR to satisfy yourself it is safe.

curl -fsSL https://raw.githubusercontent.com/dotnet/maui/main/eng/scripts/get-maui-pr.sh | bash -s -- 34409

Or

• Run remotely in PowerShell:

iex "& { $(irm https://raw.githubusercontent.com/dotnet/maui/main/eng/scripts/get-maui-pr.ps1) } 34409"

[Copilot]

Pull request overview

Fixes the dotnet-maui-build internal pipeline failure caused by the new BUILD.BUILDNUMBER format containing a +, which breaks Arcade’s MSBuild arithmetic on OfficialBuildId.

Changes:

• Switch _OfficialBuildIdArgs to use _BuildOfficialId (yyyyMMdd.counter) instead of BUILD.BUILDNUMBER.
• Keep signing/publishing-related arguments unchanged.

---

You can also share your feedback on Copilot code review. Take the survey.

[PureWeen]

Root Cause Analysis

The internal pipeline (dotnet-maui-build, definition 1536) has been failing since ~Jan 26, 2026 with MSB4186: Invalid static method invocation syntax during Arcade version computation.

What broke it

PR #33209 ("Restore OfficialBuildId for proper CI versioning", Jan 21) correctly updated the default, public, and PR conditional blocks in variables.yml to use $(_BuildOfficialId) (which resolves to yyyyMMdd.counter format). However, the internal block (lines 52-64, for dotnet-maui/dotnet-maui-build) was not updated and still used $(BUILD.BUILDNUMBER).

When the pipeline build number format subsequently changed to 10.0.50+azdo.{buildId}, the + character broke Arcade SDK's [MSBuild]::Add()/Multiply()/Subtract() calls in Version.BeforeCommonTargets.targets, which expect a numeric yyyyMMdd.counter input.

Timeline

• Jan 21: PR Restore OfficialBuildId for proper CI versioning #33209 merged — fixed public/default/PR blocks but left internal block with $(BUILD.BUILDNUMBER)
• ~Jan 26: Last successful internal build (#2886281)
• Jan 27+: Every internal build fails with MSB4186 (5+ weeks broken)

Fix

Changed the internal block to use $(_BuildOfficialId) — the same variable every other conditional block already uses. Added inline comment to prevent future regression.