Closes the NotSupportedException cliff for S7 Float64/Int64/UInt64.
- S7Size enum gains LWord (8 bytes); parser accepts DBLD/DBL on data
blocks and LD on M/I/Q (e.g. DB1.DBLD0, DB1.DBL8, MLD0, ILD8, QLD16).
- S7Driver.ReadOneAsync / WriteOneAsync issue ReadBytesAsync /
WriteBytesAsync for 64-bit types and convert big-endian via
System.Buffers.Binary.BinaryPrimitives. S7's wire format is BE.
- Internal MapArea(S7Area) helper translates to S7.Net DataType.
- MapDataType now surfaces native DriverDataType for Int16/UInt16/
UInt32/Int64/UInt64 instead of collapsing them all to Int32.
Tests: parser theories cover DBLD/DBL/MLD/ILD/QLD; discovery test
asserts the 64-bit DriverDataType mapping. 64/64 passing.
Closes#287
Per-tag opt-in for write-retry per docs/v2/plan.md decisions #44, #45, #143.
Default is false — writes never auto-retry unless the driver author has marked
the tag as safe to replay.
Core.Abstractions:
- DriverAttributeInfo gains `bool WriteIdempotent = false` at the end of the
positional record (back-compatible; every existing call site uses the default).
Driver.Modbus:
- ModbusTagDefinition gains `bool WriteIdempotent = false`. Safe candidates
documented in the param XML: holding-register set-points, configuration
registers. Unsafe: edge-triggered coils, counter-increment addresses.
- ModbusDriver.DiscoverAsync propagates t.WriteIdempotent into
DriverAttributeInfo.WriteIdempotent.
Driver.S7:
- S7TagDefinition gains `bool WriteIdempotent = false`. Safe candidates:
DB word/dword set-points, configuration DBs. Unsafe: M/Q bits that drive
edge-triggered program routines.
- S7Driver.DiscoverAsync propagates the flag.
Stream A.5 integration tests (FlakeyDriverIntegrationTests, 4 new) exercise
the invoker + flaky-driver contract the plan enumerates:
- Read with 5 transient failures succeeds on the 6th attempt (RetryCount=10).
- Non-idempotent write with RetryCount=5 configured still fails on the first
failure — no replay (decision #44 guard at the ExecuteWriteAsync surface).
- Idempotent write with 2 transient failures succeeds on the 3rd attempt.
- Two hosts on the same driver have independent breakers — dead-host trips
its breaker but live-host's first call still succeeds.
Propagation tests:
- ModbusDriverTests: SetPoint WriteIdempotent=true flows into
DriverAttributeInfo; PulseCoil default=false.
- S7DiscoveryAndSubscribeTests: same pattern for DBx SetPoint vs M-bit.
Full solution dotnet test: 947 passing (baseline 906, +41 net across Stream A
so far). Pre-existing Client.CLI Subscribe flake unchanged.
Stream A's remaining work (wiring CapabilityInvoker into DriverNodeManager's
OnReadValue / OnWriteValue / History / Subscribe dispatch paths) is the
server-side integration piece + needs DI wiring for the pipeline builder —
lands in the next PR on this branch.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
