Pass the schema default for optional inputs a prompt leaves out

[christian-byrne]

An API-format prompt saved before an optional input was added does not carry it, and get_input_data only passes the keys the prompt has, so the node is called without the argument and raises TypeError. INPUT_TYPES defaults are never injected, so the value has to come from a default in the entry function, and 75 optional inputs in core do not have one. This fills those from the schema default, which makes "optional with a default" mean the input simply does not have to be provided. It only applies where the parameter has no default of its own, so a node using a sentinel to detect a missing input, like SoftSwitchNode with MISSING, still sees it missing — and a node whose schema default disagrees with its signature default keeps using the signature. Optional inputs with no schema default are untouched; those are nullable values, and the sibling PR #15739 lints that their parameter carries a default.

Reproduced against a running server with a real API-format prompt. TestOmittedOptionalInput.scale is optional with {"default": 0.5} in the schema and no default in process(), and the prompt omits it:

{"prompt": {
  "1": {"class_type": "StubImage", "inputs": {"content": "WHITE", "height": 64, "width": 64, "batch_size": 1}},
  "2": {"class_type": "TestOmittedOptionalInput", "inputs": {"image": ["1", 0]}},
  "3": {"class_type": "SaveImage", "inputs": {"images": ["2", 0], "filename_prefix": "e2e"}}
}}

Before, validation accepts it and execution dies:

$ curl -s -X POST -d @prompt.json http://127.0.0.1:8291/prompt
{"prompt_id": "75a9a821-...", "number": 1, "node_errors": {}}

[ERROR] !!! Exception during processing !!! TestOmittedOptionalInput.process() missing 1 required positional argument: 'scale'
  File "execution.py", line 306, in process_inputs
    result = f(**inputs)
TypeError: TestOmittedOptionalInput.process() missing 1 required positional argument: 'scale'

After, it runs and the default arrives — a white image scaled by 0.5 is 127:

$ curl -s -X POST -d @prompt.json http://127.0.0.1:8291/prompt
{"prompt_id": "689703ba-...", "number": 0, "node_errors": {}}
[INFO] Prompt executed in 0.01 seconds

$ python -c "import numpy; from PIL import Image; a=numpy.array(Image.open('e2e_00001_.png')); print(a.min(), a.max())"
127 127

Tests

tests/execution/test_omitted_optional_input.py covers that over HTTP: the omitted input gets its schema default, a provided value still wins, and a connected nullable socket is still delivered. Reverting only the execution.py hunk fails 2 of the 3.

$ pytest tests/execution/test_omitted_optional_input.py -q --port 8399   # without the change
2 failed, 1 passed

$ pytest tests/execution/test_omitted_optional_input.py -q --port 8399   # with the change
3 passed

$ pytest tests/execution -q --port 8399
277 passed, 7 skipped in 92.08s

$ pytest tests-unit -q
1257 passed, 10 skipped

tests-unit/execution_test/omitted_optional_input_test.py adds the unit-level cases, including that a V3 node resolves through execute rather than the EXECUTE_NORMALIZED trampoline.

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Reviewing files that changed from the base of the PR and between 5ab2f7a and fd68491.

📒 Files selected for processing (4)

• execution.py
• tests-unit/execution_test/omitted_optional_input_test.py
• tests/execution/test_omitted_optional_input.py
• tests/execution/testing_nodes/testing-pack/specific_tests.py

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[christian-byrne]

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