[magnusp]

Summary

resolveDatabaseProductVersion no longer swallows a failed SELECT sqlite_version(). The "3.0" fallback is gone, the failure surfaces as a SQLException, and the next call retries. A closed connection now throws instead of returning a version, including when a version is already cached.

Fixes #112

Contract

Hrana 3 governs select sqlite_version() through execute; java.sql governs DatabaseMetaData; xerial/sqlite-jdbc is a behavioral reference only.

Change

• resolveDatabaseProductVersion calls connection.checkClosed() before returning a cached value, so a closed connection throws even after a successful lookup.
• The catch (SQLException) that wrote "3.0" into cachedDatabaseProductVersion is removed. Only a real version from the server is cached.
• An empty result now throws SQLException("SELECT sqlite_version() returned no row") instead of falling back to "3.0".

Divergences

• Empty result throws instead of returning "3.0". sqlite_version() always returns one row, so an empty result is a broken server response, not a legitimate default. Keeping the fallback, cached or not, would reintroduce the lie this issue reports.
• cachedDatabaseProductVersion stays unsynchronized. Two concurrent first calls can each run the lookup; the last write wins and both values are real versions, so no fallback can be pinned. This is recorded for LibsqlConnection state is not synchronized #105, which owns connection-level concurrency.

Evidence

Red at trunk 4725e83, tests only, fix not applied (/tmp/xerial-parity-i112/lane-1-regression.log): Tests run: 27, Failures: 2 — both new cases fail with "Expecting code to raise a throwable."

Green at head c924c4b4c7bb:

• Lane 1/2 (LibsqlDatabaseMetaDataTest): Tests run: 27, Failures: 0, Errors: 0. The failed lookup throws, the retry returns 3.45.1.
• Lane 3: major/minor derive from the recovered value (3, 45).
• Lane 4 (-pl libsql-jdbc test): Tests run: 235, Failures: 0, Errors: 0, BUILD SUCCESS.
• Lane 5 (-pl libsql-conformance -am verify): Tests run: 115, Failures: 0, Errors: 0, Skipped: 1, BUILD SUCCESS, no new divergence.
• Lane 6 (-Pxerial-control verify): Tests run: 100, Failures: 0, Errors: 0, Skipped: 1, BUILD SUCCESS; no new reference difference.
• Lane 7 (spotless:check): BUILD SUCCESS.
• Lane 8 (./mvnw test): BUILD SUCCESS.
• Lane 10 (-pl libsql-jdbc -am package -DskipTests): jar built.

Lane 9: the diff keeps cachedDatabaseProductVersion unsynchronized; the #105 note above is the handoff.

Files touched: libsql-jdbc/src/main/java/com/github/magnusp/libsql/jdbc/LibsqlDatabaseMetaData.java, libsql-jdbc/src/test/java/com/github/magnusp/libsql/jdbc/LibsqlDatabaseMetaDataTest.java.

Base 4725e83 · Head c924c4b4c7bb.