Python 3.13: CALL self-slot fix, CALL_KW, and assorted missing opcodes

[sfz001]

Summary

Adds the Python 3.13 call-path opcodes that pycdc was still missing, and fixes a latent bug in CALL_A where the direction of the NULL self-slot surrounding the callable was hard-coded.

The call self-slot direction bug

In 3.11+, every CALL expects both a callable and a NULL self-slot on the stack. Which one is deeper depends on how the callable was loaded:

• LOAD_GLOBAL with the +NULL flag pushes [NULL, callable] (NULL deeper);
• LOAD_ATTR followed by a separate PUSH_NULL pushes [callable, NULL] (NULL on top).

The second form is the common pattern for non-method calls in 3.13 (e.g. json.dumps({}, ensure_ascii=False)). The existing handler only looked for the first layout, so those calls decompiled as None(...). We now check for both arrangements.

New opcodes handled

Opcode	Behaviour	Related issue
MAKE_FUNCTION (no operand, 3.13)	Pop code object, push empty ASTFunction	#542, #569, #595
SET_FUNCTION_ATTRIBUTE	Keep function on top, drop the attribute value
CALL_KW	KW-names tuple at TOS, operand = total arg count	#587
TO_BOOL	no-op for decompile	#540
MAKE_CELL, COPY_FREE_VARS	prologue ops, no stack effect
LOAD_FAST_CHECK, LOAD_FAST_AND_CLEAR	behave like LOAD_FAST
STORE_FAST_STORE_FAST, STORE_FAST_LOAD_FAST	split into component ops
POP_JUMP_IF_NONE, POP_JUMP_IF_NOT_NONE	reuse POP_JUMP_IF_FALSE/TRUE pipeline

The SET_FUNCTION_ATTRIBUTE handler currently discards the attribute value (defaults/kwdefaults/annotations/closure cells). That is intentionally minimal — PRs #579 and #581 have more complete treatments. Until one of those lands, this at least lets functions decompile instead of silently crashing.

Test

Added tests/input/call_kw_3_13.py, compiled as .3.13.pyc, covering both the CALL_KW and LOAD_ATTR + PUSH_NULL + CALL_KW patterns:

import json

def greet(name, greeting='hello'):
    return greeting + ', ' + name

print(greet('world', greeting='hi'))
print(json.dumps({}, ensure_ascii=False))

Before this patch the last line decompiled to None({}, ensure_ascii=False).

What this does not fix

Still missing from 3.13 decompilation (filed in #547 and elsewhere):

• FORMAT_SIMPLE / CONVERT_VALUE (f-strings)
• CALL_INTRINSIC_1 / CALL_INTRINSIC_2 (most variants)
• CALL_FUNCTION_EX
• DICT_MERGE / DICT_UPDATE / MAP_ADD
• PEP 695 class-parameter nodes (NODE_TYPEPARAM, seen as Unsupported Node type: 27)

I have ad-hoc stubs for a few of those in a working branch, but they're hacks; better to leave them for a follow-up once someone implements them properly.

[zrax]

Suggestion: Might be worth adding an xfail case for these attributes if possible, so it's easier to see what's missing...

[zrax]

Probably worth merging these cases rather than duplicating their content. The comments can be added under the case labels, with a fallthrough attribute if the compiler requires it.