clippy.toml

# Workspace clippy config. Read by cargo-clippy at the workspace root.
#
# WHY disallowed-methods on rusqlite::Connection::open:
# Opening a second writable Connection handle to a DB file already
# managed by the SqliteWriter actor is the bug class behind GH #131
# (intermittent test deadlock). SQLite 3.51.0-3.51.1 contained an
# lock-order-inversion lock-order inversion in unixClose vs unixLock-from-WAL-close
# that turned the pattern into a hard hang. The bug is fixed in
# 3.51.2+ (we ship 3.51.3 via rusqlite 0.39), but the *pattern* is
# still fragile to future SQLite regressions and to GRDB.swift #739
# style close-ordering issues.
#
# What's allowed (and why, honestly):
#   * Connection::open_with_flags(..., SQLITE_OPEN_READ_ONLY | NO_MUTEX)
#     — does NOT prove immunity from the upstream lock-order-inversion close race
#     (RO Connections still go through unixClose -> sqlite3WalClose
#     and register a unixInodeInfo). What it DOES buy: cannot write
#     concurrently with the SqliteWriter, cannot accidentally CREATE
#     the file, and signals "inspection-only" intent at code-review
#     time. Used by db/tests/writer_hlc_* and cli/tests. Upstream
#     immunity comes from rusqlite >= 0.39 (SQLite >= 3.51.2).
#   * SqliteWriter::start[_in_memory] — the singleton write entry point.
#   * Open of a separate DB file (not the main perima.db) — flagged
#     case-by-case via #[allow(clippy::disallowed_methods)] + WHY.
#
# Exceptions are #[allow]-annotated with a WHY-comment at the call
# site. There are 3 today (manifest.rs, search_repo seed_conn, app
# search seed_via_conn). Adding a 4th means thinking hard first.
disallowed-methods = [
    { path = "rusqlite::Connection::open", reason = "Opens a second writable Connection. Use perima_db::SqliteWriter for writes; use Connection::open_with_flags(SQLITE_OPEN_READ_ONLY) for read-only inspection. See clippy.toml header + GH #131." },
]