test(pyamber): add unit test coverage for AddInputChannelHandler

[eugenegujing]

What changes were proposed in this PR?

Adds test_add_input_channel_handler.py (12 tests) for core/architecture/handlers/control/add_input_channel_handler.py. The handler's three-line is_control block looks like a no-op but is load-bearing: Message.__hash__ is patched to hash-of-repr, betterproto's repr omits fields left at their default, and proto3 never puts false on the wire — so a data channel's ChannelIdentity arrives ==-equal to its canonical form yet hashing differently, and InputManager keys its channel registry by that hash. test_main_loop.py drives AddInputChannel end to end on the happy path but never pins the materialization, so the workaround could regress silently.

Every request in the spec is built through a bytes round trip so the handler receives the real wire shape — an in-process request would arrive already canonical and prove nothing. The spec pins:

• the delegation: register_input is the input manager's only call, with the request's channel and port, and the handler returns EmptyReturn;
• the channel id is canonical by the time register_input receives it, asserted by snapshotting the hash inside a side effect — a key inserted at the pre-materialization hash and then mutated in place strands the dict entry;
• the consequences on a real InputManager: the registered channel resolves through get_port_id, survives the is_control read that get_all_data_channel_ids() performs on every key, and is interchangeable as a dict key with an independently built canonical id in both directions;
• control channels arrive already canonical (proto3 does serialize true) and keep their marker, guarding the if not condition against inversion;
• port 0, the default port, registers correctly even though its identity arrives as a bare PortIdentity() (proto3 omits both id=0 and internal=False). This is complementary to test_input_manager.py::TestPortIdentityDefaults, which feeds a hand-built PortIdentity(id=None, internal=None) — a shape no production caller of register_input produces; the wire shape exercised here is what the two wire-fed callers actually deliver, and it is canonicalized by attribute reads alone, not by the is None branches;
• a canary pins the wire premise itself, so a betterproto upgrade that starts materializing defaults on parse reports itself instead of quietly making the rest of the file meaningless.

Any related issues, documentation, discussions?

Closes #7748.

How was this PR tested?

12 new tests, all green locally:

cd amber
pytest src/test/python/core/architecture/handlers/control/test_add_input_channel_handler.py -q   # 12 passed
pytest src/test/python/core/architecture/ -q                                                     # 303 passed
pytest src/test/python/core/runnables/test_main_loop.py -q                                       # 34 passed
pytest -m "not integration" -q                                                                   # 1068 passed
ruff check src/main/python src/test/python && ruff format --check src/main/python src/test/python

The only full-suite failures are the pre-existing core/storage/iceberg/test_iceberg_document.py items that need a local catalog stack; they fail identically without this PR.

The tests were also mutation-checked: deleting the handler's is_control block, always assigning False (guard inversion), canonicalizing after register_input instead of before, swapping the delegation arguments, dropping the call entirely, and deleting register_input's id is None guard each turn the expected tests red.

Was this PR authored or co-authored using generative AI tooling?

Generated-by: Claude Code (Claude Opus 5)

[github-actions]

Automated Reviewer Suggestions

Based on the git blame history of the changed files, we recommend the following reviewers:

• No candidates found from git blame history.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.03%. Comparing base (e80add4) to head (570c8c0).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #7750   +/-   ##
=========================================
  Coverage     91.03%   91.03%           
  Complexity     4459     4459           
=========================================
  Files          1174     1174           
  Lines         47139    47139           
  Branches       5284     5284           
=========================================
  Hits          42915    42915           
  Misses         2549     2549           
  Partials       1675     1675           

Flag	Coverage Δ		*Carryforward flag
access-control-service	81.00% <ø> (ø)		Carriedforward from e80add4
agent-service	98.62% <ø> (ø)		Carriedforward from e80add4
amber	87.49% <ø> (ø)		Carriedforward from e80add4
computing-unit-managing-service	73.67% <ø> (ø)		Carriedforward from e80add4
config-service	86.73% <ø> (ø)		Carriedforward from e80add4
file-service	68.90% <ø> (ø)		Carriedforward from e80add4
frontend	92.58% <ø> (ø)		Carriedforward from e80add4
notebook-migration-service	83.74% <ø> (ø)		Carriedforward from e80add4
pyamber	97.57% <ø> (ø)
workflow-compiling-service	77.19% <ø> (ø)		Carriedforward from e80add4

*This pull request uses carry forward flags. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[github-actions]

⚠️ Benchmark changes need a look

🟢 6 better · 🔴 3 worse · ⚪ 6 noise (<±5%) · 0 without baseline

Compared against main 60300e3 benchmarked on this same runner, so the delta is largely free of cross-runner hardware noise. The "7d avg" column still reflects the gh-pages dashboard. Treat <±5% as noise unless repeated.

Dashboard · Run

	config	throughput	MB/s	latency	max Δ latest / 7d
🔴	bs=10 sw=10 sl=64	370	0.226	26,338/31,279/31,279 us	🟢 -21.5% / 🔴 +105.5%
🟢	bs=100 sw=10 sl=64	786	0.48	125,039/156,711/156,711 us	🟢 -13.1% / 🔴 +46.1%
⚪	bs=1000 sw=10 sl=64	911	0.556	1,094,775/1,152,893/1,152,893 us	⚪ within ±5% / 🔴 -13.1%

Baseline details

Latest main 60300e3 from same runner

config	metric	PR	latest main	7d avg	Δ latest	Δ 7d
bs=10 sw=10 sl=64	throughput	370 tuples/sec	395 tuples/sec	779.07 tuples/sec	-6.3%	-52.5%
bs=10 sw=10 sl=64	MB/s	0.226 MB/s	0.241 MB/s	0.476 MB/s	-6.2%	-52.5%
bs=10 sw=10 sl=64	p50	26,338 us	22,619 us	12,818 us	+16.4%	+105.5%
bs=10 sw=10 sl=64	p95	31,279 us	39,841 us	15,986 us	-21.5%	+95.7%
bs=10 sw=10 sl=64	p99	31,279 us	39,841 us	19,339 us	-21.5%	+61.7%
bs=100 sw=10 sl=64	throughput	786 tuples/sec	747 tuples/sec	1,011 tuples/sec	+5.2%	-22.3%
bs=100 sw=10 sl=64	MB/s	0.48 MB/s	0.456 MB/s	0.617 MB/s	+5.3%	-22.2%
bs=100 sw=10 sl=64	p50	125,039 us	129,591 us	100,965 us	-3.5%	+23.8%
bs=100 sw=10 sl=64	p95	156,711 us	180,273 us	107,295 us	-13.1%	+46.1%
bs=100 sw=10 sl=64	p99	156,711 us	180,273 us	115,531 us	-13.1%	+35.6%
bs=1000 sw=10 sl=64	throughput	911 tuples/sec	888 tuples/sec	1,049 tuples/sec	+2.6%	-13.1%
bs=1000 sw=10 sl=64	MB/s	0.556 MB/s	0.542 MB/s	0.64 MB/s	+2.6%	-13.1%
bs=1000 sw=10 sl=64	p50	1,094,775 us	1,124,352 us	978,248 us	-2.6%	+11.9%
bs=1000 sw=10 sl=64	p95	1,152,893 us	1,182,880 us	1,021,881 us	-2.5%	+12.8%
bs=1000 sw=10 sl=64	p99	1,152,893 us	1,182,880 us	1,050,075 us	-2.5%	+9.8%

Raw CSV

config_idx,batch_size,schema_width,string_len,num_batches,total_ms,total_tuples,total_bytes,tuples_per_sec,mb_per_sec,lat_p50_us,lat_p95_us,lat_p99_us
0,10,10,64,20,540.04,200,128000,370,0.226,26337.50,31279.48,31279.48
1,100,10,64,20,2544.13,2000,1280000,786,0.480,125039.27,156711.22,156711.22
2,1000,10,64,20,21958.15,20000,12800000,911,0.556,1094774.76,1152892.93,1152892.93