[alaricd]

Summary

DuckDB.NET reports DbTransaction.SupportsSavepoints == false, and Save/Rollback reject savepoint operations, but the inherited Release and ReleaseAsync methods complete successfully. This violates the DbTransaction.SupportsSavepoints capability contract.

This change explicitly keeps savepoints unsupported and makes synchronous and asynchronous Release reject the operation with NotSupportedException.

It also fixes AbortedTransactionTest, which began a transaction it never disposed. TransactionTests share one connection, so the next test to call BeginTransaction failed with "Already in a transaction." The new savepoint test was the first to run after it, which is why CI failed on the first commit.

Verification

• Added SavepointsAreNotSupportedTest covering the capability flag and all sync/async savepoint methods.
• Full DuckDB.NET.Test suite passes locally (net8.0): 7567 passed, 0 failed.
• pengdows.AdoNetApiTest.conformance source-backed DuckDB profile passes: Required 119/119; ADO.NET, EF Core, and pengdows.crud certified.

Found by pengdows.AdoNetApiTest.conformance.

[Giorgi]

Tests are failing on all platforms

[coveralls]

Coverage Report for CI Build 39760727321

Coverage increased (+0.002%) to 92.792%

Details

• Coverage increased (+0.002%) from the base build.
• Patch coverage: 2 of 2 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	4276
Covered Lines:	4034
Line Coverage:	94.34%
Relevant Branches:	2564
Covered Branches:	2313
Branch Coverage:	90.21%
Branches in Coverage %:	Yes
Coverage Strength:	970630.78 hits per line

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💛 - Coveralls

[alaricd]

Thanks, fixed in 77bfadf. The new test wasn't the cause. AbortedTransactionTest began a transaction it never disposed, and since TransactionTests share one connection, the next test to call BeginTransaction failed with "Already in a transaction." The savepoint test happened to run next. That test now disposes its transaction, and the build passes on all three platforms.