Root cause (in 0.2.1 and still on main): files and folders named on the
command line were imported from the eframe app-creator closure with
`app.run("library.import", …)`, which runs the engine command synchronously:
`import::expand` walked the folder recursively (one `is_dir()` open per entry,
no depth or count bound, following links) and probed every file before the
first frame could be drawn. An argument that resolves to a drive root (`.` or
`..` with a launcher's working folder at `C:\`, `/` or `\` on Windows) or to
the home folder therefore walked the whole drive with the window stuck as a
black "not responding" box. The library-problem banner's pending import had
the same synchronous call. Every other recursive walk (Local's Include
Subfolders, Find Missing Photos, preset and LUT folders, MCP) was also
unbounded, which is the "Local folders with subfolders: not responding"
pattern of filmcraft#23, and a link loop recursed until the stack overflowed.
- engine `walk::files_in`: one bounded, iterative walker (32 folder levels,
1,000,000 entries; `Walked::truncated` says it stopped), folder or file
taken from the directory listing (no open per entry), links and junctions
to a folder followed once. `import::expand` (+ `expand_within`), preset and
LUT folder expansion and MCP `expand_paths` use it.
- engine `import::launch_path`: an empty launch argument is ignored; a
relative one is resolved against the working folder; a drive or file-system
root becomes its memory card's DCIM folder or is refused, and so is the home
folder (a notice says why and to use File > Import Photos).
- desktop: launch arguments go through it and are imported with
`import::start_paths` (the import worker), like dropped files; so does the
library-problem banner's pending import.
Not verified on Windows (no machine here). The report says PhotoCraft 0.5.0
and `--memory` hang the same way with no arguments; nothing in LightCraft
walks the disk at startup without arguments (strace of a headless demo run
with HOME=/ and cwd /: no recursive listing), so that part may be outside
this code.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01912WaK6Rmew3wxZuPyX7E8
