v3.2.0: 2.4× faster treemap, 24% less memory, duplicate finder, Recycle Bin

[MrHakan]

Summary

Optimization pass driven by measurement, plus three functional additions. Everything below was benchmarked on a 7,300-file tree before touching the code and again after.

Performance

	Before	After
Hover one tile	242 ms	~0.2 ms
Treemap render	246 ms	103 ms (2.4×)
Tree memory	392 B/node	296 B/node (−24%)

The hover number was the real bug. Moving the pointer across a tile boundary re-rendered the entire map just to move the highlight outline. The outline is now a canvas item drawn on top of the cached image, so the image is never rebuilt.

The render win came from profiling, not guessing — and my first attempt actually made it slower (246→493 ms) before the profiler showed why:

• Shading each tile allocated four temporary images plus two blends and a composite. Cushions are now built once per colour at a few resolutions, and each tile is a single resize from the nearest level. Scaling everything from one large source was still reading the whole source for a 20px tile.
• Pillow re-rounds a list LUT in Python on every call — 4.2 million round() calls in the profile. The LUTs are bytes now.
• Tiles under 8px are filled flat; the gradient can't be seen at that size.
• Tile colour is memoised by extension instead of re-deriving the category per tile.

Memory

• Node exists once per file on disk. Swapping the dataclass __dict__ for __slots__, and letting files share one empty children container instead of each allocating a list they can never use, cut 24% per node.
• Thumbnail requests snap to size buckets, so resizing the window reuses decodes instead of re-decoding every image at its new exact size; JPEGs also decode at reduced scale via draft().
• Thumbnail and cushion caches are bounded by total pixels, not entry count — a few large entries cost far more than many small ones.
• The row-preview map is cleared alongside the rows it points at, and capped.

New features

• 👯 Duplicates view — finds byte-identical copies in three widening stages (size → head/tail sample → full hash), so almost nothing is read twice. Shows exactly what keeping one of each would free, runs in the background, is cancellable, and its rows feed the existing zip/delete actions.
• ♻️ Recycle Bin — deletions are undoable by default (Windows shell API, XDG trash elsewhere), with an automatic fallback and a setting for permanent delete.
• 🖼️ Treemap PNG export alongside the CSV report.

Testing

• 133 tests pass (up from 104), including new coverage for the duplicate finder (same-size-but-different content, mid-file differences that fool the cheap sample, cancellation), the trash helper (real move + restore metadata + name collisions), and each optimization, so they can't quietly regress.
• Drove the new views through the real UI headlessly and confirmed hover does no re-render.
• Compared the rendered treemap before and after to verify the cheaper path looks identical — no quality traded for speed.

Version 3.2.0.

🤖 Generated with Claude Code

https://claude.ai/code/session_011HEb3UbLzGGY4KuK54H45Q

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Generated by Claude Code

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