ISO-15765: Project Structure and Integration Test Coverage¶

This document describes the project structure for ISO-15765 (ISO-TP) tests and the current integration test coverage. It highlights what is implemented and verified, and where there are gaps in implementation or tests.

Project Structure (Relevant to ISO-TP and Tests)¶

• ISO-TP core (protocol implementation): src/isotp.c
• Public API and link model: isotp.h
• Protocol definitions and result codes: inc/isotp_defines.h
• Build-time configuration (BS, STmin, timeouts, options): inc/isotp_config.h
• Platform hooks (CAN, time, debug): inc/isotp_user.h
• Python bindings and CAN/time mocks (test layer): examples/python_api/src
• Integration tests (Python): tests/integration
• Integration test documentation: docs/integration_tests

Implemented and Verified by Integration Tests¶

The following areas are implemented in the core and covered by integration tests:

• API smoke + input errors + return codes

  • Tests: tests/integration/test_api_endpoints.py
  • Docs: integration_tests/api_endpoints.md
  • Scope: SF/MF smoke, sender N_Bs timeout, invalid args, overflow, in-progress.

• API validation (arguments)

  • Tests: tests/integration/test_api_validation.py
  • Docs: integration_tests/api_validation.md
  • Scope: zero buffers, bufsize=0, block_size > 255.

• Buffer limits and overflow handling

  • Tests: tests/integration/test_buffer_limits.py
  • Docs: integration_tests/buffer_limits.md
  • Scope: ISOTP_RET_OVERFLOW, truncation on receive, ISOTP_RET_INPROGRESS.

• Multi-frame behavior (FF/CF, SN, BS, STmin, timeouts)

  • Tests: tests/integration/test_multi_frame.py
  • Docs: integration_tests/multi_frame.md
  • Scope: MF roundtrip, 8/9/14/15 boundaries, max payload 4095B, BS=1 and BS=0, STmin, N_Bs/N_Cr timeouts, UNEXP_PDU and WRONG_SN errors.

• FlowControl (FS=WAIT/CONTINUE/OVERFLOW)

  • AUTOSAR CanTp: tests/integration/test_cantp.py,
  • Docs: integration_tests/cantp.md,
  • Tests: tests/integration/test_flow_control.py
  • Docs: integration_tests/flow_control.md
  • Scope: WAIT -> CONTINUE, WFT overrun, FS=Overflow, BS and STmin parameters.

• Timing (N_Bs, N_Cr, STmin, BS)

  • Tests: tests/integration/test_timing.py
  • Docs: integration_tests/timing.md
  • Scope: N_Bs and N_Cr timeouts, STmin enforcement, BS=1 roundtrip.

Implementation Gaps (Explicitly Identified)¶

• N_As, N_Ar, N_Br, N_Cs are not enforced in the core yet (marked as xfail in timing tests). See: tests/integration/test_timing.py and integration_tests/timing.md.

Integration Test Gaps (Areas to Expand)¶

Based on current integration tests, there is no visible coverage for:

• isotp_send_with_id (functional addressing) in isotp.h.
• tx_done_cb and rx_done_cb callbacks (when enabled in config) in isotp.h and inc/isotp_config.h.
• ISO_TP_FRAME_PADDING (padded frames) in inc/isotp_config.h.
• ISOTP_RET_NOSPACE scenarios (retry send) in inc/isotp_defines.h.
• Invalid FlowControl (e.g., invalid FS) and other protocol errors beyond UNEXP_PDU and WRONG_SN in inc/isotp_defines.h.
• Transfers larger than 4095B (long FF) - no integration tests yet.

Notes¶

• Integration tests are executed via Python bindings and CAN/time mocks (see examples/python_api/src).
• This document only covers integration test coverage. Unit tests may cover additional areas.