Fix VOID failing with RuntimeError (CORE-205)

[Talmaj]

start (0) + length (464) exceeds dimension size (461).

Some very short and long clips were failing within tiled_scale_multidim function.

Root cause: The output buffer is pre-allocated using round(get_scale(dim, total_size)), but when a callable index_formula is used (as the void 3D VAE does to handle non-linear temporal upscaling), the formula applied to an individual tile position + tile size can round up to 1-3 more pixels than what the total allocation computed. You got 464 but the buffer only had 461 slots.

Fix: Before narrowing into the output buffer o, clamp l to o.shape[d+2] - upscaled[d] — the actual remaining space. If a tile is trimmed, we narrow ps_view and mask_view from position 0 to the same l, so shapes stay consistent. Dropping the last 3 pixels of a tile that overlaps a border is harmless because those pixels are feathered to near-zero by the mask anyway.

[coderabbitai]

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Reviewing files that changed from the base of the PR and between a5189fe and dce0c22.

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• comfy/utils.py

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📝 Walkthrough

Walkthrough

This PR fixes a tile-accumulation bug in tiled_scale_multidim where edge tiles could produce output slices smaller than their corresponding tile (ps) and mask tensors. The fix replaces the previous unconditional narrowing approach with a per-dimension loop that crops both the output accumulators and tile/mask views to match when partial tiles occur, then performs the weighted accumulation using aligned tensor shapes.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title correctly identifies the main issue being fixed (VOID RuntimeError) and is directly related to the core change in the changeset.
Description check	✅ Passed	The description is clearly related to the changeset, providing detailed context about the error, root cause, and the implemented fix for the tiled_scale_multidim function.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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