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OrcaSlicer/tests
Ian Chua 323cd3afe1 Keep Python Printer Agent Exceptions Out of the Host (#15819)
# Description
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A Python printer agent plugin could take the host down, and one of its
operations could never report its result. This PR fixes both in
`PrinterAgentPluginCapabilityTrampoline.hpp`.

## Changes

### A faulty printer agent no longer throws into the GUI

`IPrinterAgent` reports failure through return values, and none of its
callers catch. A Python `raise`, a missing override or a wrongly typed
return from a printer agent plugin therefore escaped the trampoline as a
C++ exception.

Every trampoline operation now catches, logs `Printer agent plugin
'<key>': <operation> failed: <error>`, and answers with what
`NetworkAgent` returns when no printer agent is set. `BBLPrinterAgent`
returns the same values when the Bambu plug-in is unavailable:

- `-1` for every `int` status code
- `false` for `start_discovery` and `fetch_filament_info`
- `""` for `get_user_selected_machine`
- an empty `AgentInfo` for `get_agent_info` (registration already
rejects an empty agent ID)
- `FilamentSyncMode::none` for `get_filament_sync_mode`

`ORCA_PY_AGENT_OVERRIDE(ret, name, ...)` derives the fallback from the
return type through `printer_agent_failure<ret>()`, so the call sites
carry no fallback values of their own.

An exception is the safety net for plugin bugs, not an error channel. A
plugin reports an expected failure by returning a code, as the Bambu
plug-in does. A raise is logged as a failure and collapses to the
generic `-1`, so the GUI shows the generic message instead of the
specific one (`-18` cancelled, `-4020` FTP upload failed, …).

### `bind_detect` results now reach the host

`detect` is an out-parameter (`detectResult&`). pybind11 casts a
reference argument to an override with a copy, so a plugin that filled
in `detect` wrote to a throwaway object and the host always saw an empty
`detectResult`. It is now passed so that Python edits the caller's
struct. Plugins see the same `DetectResult` argument as before.

## TODO

- Expose the `BAMBU_NETWORK_*` return codes to Python (the
`orca.printer_agent` binding and the generated stub from
`scripts/generate_orca_python_stubs.py`). Plugins can already return
them, but only as hard-coded numbers.

# Screenshots/Recordings/Graphs

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## Tests

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changes made in this PR.
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- New `tests/slic3rutils/test_plugin_printer_agent.cpp`: an agent whose
operations raise, one that omits them, and one that returns the wrong
type all answer like a missing agent, and the interpreter stays usable.
A working agent's answers reach the host unchanged, including
`request_bind_ticket`'s out-param and the fields a plugin writes into
`bind_detect`'s `detect`.
- The `bind_detect` check failed before the fix (`"" == "192.168.0.2"`)
and passes after.
- `slic3rutils` passes under `ctest` (144/144); full Release build clean
on Linux.
- End to end on Linux with a test plugin whose chosen operations raise
(`start_discovery`, `get_filament_sync_mode`, `disconnect_printer`):
selecting the plugin's agent in the printer preset and switching back
logged each raise as a `Printer agent plugin '…': <operation> failed`
line, and the app kept running and closed cleanly (exit 0). Without the
guard, the first raise (`start_discovery`, on selecting the agent) ended
the app with `Uncaught exception` and SIGABRT (exit 134); that run used
a build whose printer-agent files are identical to `main`.

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[How to Download Pull Requests Artifacts for
Testing](https://www.orcaslicer.com/wiki/how_to_download_pr_artifacts)
2026-09-22 16:57:55 +08:00
..
2025-12-08 22:42:11 +08:00

OrcaSlicer tests

Building, running and writing tests is documented on the wiki, under How to Test.

Two files here rather than there, because coding agents only read what is in the repository:

  • AGENTS.md is the same guidance in short form, and is what an agent working under tests/ picks up.
  • CATCH2.md is the Catch2 reference, including the mistakes that break a test at runtime.