test(integration): MCUboot raw serial recovery (SMPSerialRawTransport)

[JPHutchins]

Summary

Adds the integration test for MCUboot raw (non-console) serial recovery — the raw-framing analog of the existing base64 tests/integration/test_serial_recovery.py. A fully-featured app reboots into MCUboot serial recovery via os reset boot_mode=BOOTLOADER, and the bootloader's SMP server — built with MCUboot's raw recovery protocol (BOOT_SERIAL_RAW_PROTOCOL, mcu-tools/mcuboot#2755) — reassembles a fragmented image upload over SMPSerialRawTransport.

Closes #118. Unblocked by intercreate/smp-server-fixtures#9 (closes smp-server-fixtures#8), which built the fixture for mps2_an385 (emulated) — so this PR also adds the socket-backed raw transport the issue anticipated.

Test-only: no production (src/) changes — everything lives under tests/.

Harness

• servers.py — add QemuSocketSerialRawTransport, the raw counterpart of QemuSocketSerialTransport: an SMPSerialRawTransport whose byte pipe is the emulator's socket:// chardev (sidesteps the PTY held-byte quirk of an emulated UART). Both socket fixtures override only connect — framing, fragmentation, send, and receive are inherited from the real transports unchanged, so the suite exercises the real send rather than a copy of it. The shared socket-connect retry loop is factored out of both into _connect_socket_chardev, which also gives the socket conn an out_waiting of 0 (pyserial's socket:// backend omits it) so the inherited send's _drain_tx poll is a no-op. The accommodation lives entirely in the test backend; the production transport is untouched.
• conftest._build_transport — SocketSerialEndpoint now branches on fixture.transport, routing serial_raw to the new transport (exhaustive match with assert_never).

Tests

• test_serial_recovery_raw.py (new) — reboot → reconnect raw → upload → assert the bootloader reassembles the fragmented upload + assert_chunks_maximized. Raw recovery carries the whole SMP message in its receive buffer with no base64/length/CRC framing, so the transport's mtu is the per-message cap (the recovery server advertises no MCUmgr params → max_unencoded_size falls back to mtu). Parametrized at mtu 384 (the raw default) and 1024 (fills MCUboot's recovery buffer).
• test_image_management.test_dfu_upload — now accepts the raw transport too (the new fixture is the first serial_raw fixture with the img group). The encoded-only line-packet burst skip stays gated behind isinstance(transport, SMPSerialTransport); encoded behavior is unchanged.
• Consolidated a duplicated _signed_image helper into conftest.signed_image.

The new fixture also joins the generic connected_server suite, so the socket-backed raw transport now runs echo / enumeration / params / fs round-trips and DFU-to-app, in addition to the dedicated recovery test.

Fixtures (additive vendoring)

Only the one new fixture is vendored — the existing 0eae053d set is left untouched, per the request to add rather than replace:

• Vendors zephyr_f33aa2bc4a43_smp_server_c8f44c41_mps2_an385_serial_recovery_raw.{hex,signed.bin} from the pinned c8f44c41 release (sha256-verified).
• The artifact prefix (…c8f44c41…) differs from the 0eae053d set, so there's no collision. manifest.json and SHA256SUMS are merged additively (the manifest.json digest line was refreshed to keep SHA256SUMS internally consistent).
• VERSION documents the mixed provenance: BOOT_SERIAL_RAW_PROTOCOL merged after 4.4.0's MCUboot pin, so this one fixture is built from a post-4.4.0 Zephyr main commit (f33aa2bc); re-vendor the whole set from one release once that lands in a tagged Zephyr.

Test plan

• camas test_integration — 219 passed, 96 skipped, 0 failed (qemu mps2 + native_sim). The new fixture: 12 passed (raw DFU to app + to bootloader recovery, echo, enum, params, fs, buf-sizing), 5 skipped (encoded-only fragmentation + UDP).
• test_serial_recovery_raw.py — both mtu-384 and mtu-1024 pass; the bootloader's raw recovery buffer accommodates 1024-byte messages.
• camas check — ruff + pydoclint + mypy + unit tests pass.
• Existing test_serial_recovery.py (encoded) still passes after the signed_image consolidation.
• Full CI green (incl. the integration (native_sim + qemu) job and the lint-and-test matrix across macOS/ubuntu/ubuntu-arm/windows × Python 3.10–3.14).

Related

• mcu-tools/mcuboot#2755 — raw (non-console) SMP recovery protocol (the bootloader side this test exercises)
• intercreate/smp-server-fixtures#9 / Feature/ic upload #8 — the vendored raw recovery fixture
• feat: add SMPSerialRawTransport for Zephyr raw UART SMP #106 — SMPSerialRawTransport + the native_sim serial_raw integration coverage this builds on

🤖 Generated with Claude Code

https://claude.ai/code/session_01KKXy7L2Udjw929nie2c363

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[JPHutchins]

comment