With the trait in place the claim still meant nothing while every caller
named dr_decode's free functions: a second decoder would have had to be
threaded through the scan, the thumbnail ladder, import, the viewer,
export, merge and repairs at the moment it arrived.
Each of those now takes a &dyn Decoder and reads headers, previews,
orientation and sensor data through it, including the header budget a
remote fetch asks for (header_bytes) and where it finds the embedded
preview (locate_preview). Only the places that start a job name
dr_decode::default(): the thumbnail, sweep and thumbnail-sweep threads,
the viewer's open handlers, and the request structs a job is handed
(BatchRequest, MergeRequest, the import Request, the repairs Toolkit),
so a caller can be given another decoder by changing what it is handed.
The default is rawler through the same free functions as before, so
nothing a user sees changes. The trait gains Debug as a supertrait so
request structs that derive Debug can carry one.
library.rs was 7,729 lines wiring together everything "open a remote
library" touches: scanning, pulling other devices' judgements out of
sidecars found along the way, writing local edits back out to the
sidecar outbox, pushing/reloading XMP by hand, fetching and prefetching
thumbnails and originals, generating thumbnails locally, the metadata
and thumbnail background sweeps, on-disk paths for the catalog and
model files, and reading the grid's cells, spans and rating filter.
Same motivation as the develop.rs split (docs/dev/code-health.md CH-1):
a pure, no-behaviour-change move into one file per area, each under
about 1,500 lines.
Tracing actual call sites rather than trusting the file's physical
layout mattered here: `persist`, `load_folder_etags`, `pull_sidecars`,
`load_sidecar_etags`, `record_sidecar_read` and `apply_judgement` sit
textually beside the XMP push/reload functions but are called only
from `run_scan` (pulling a device's own past judgements out of the
sidecars a scan just walked), so they went to scan.rs and not xmp.rs.
`cells` came out at over 1,800 lines once its tests moved with it and
split further into cells.rs (windowed reads, trash, ordinals) and
spans.rs (collection scope, manual reordering, the capture-time
histogram) -- ten submodules rather than the nine first planned.
Previously-private items reached from a sibling module became
`pub(super)`, narrower than the whole-crate reachability one file gave
them. Tests moved with the code they test; the two test fixtures used
across more than one file (`scanned`, and develop.rs's
`session_with_a_left_half_subject` in the matching commit) joined the
shared `test_support` module alongside the existing `entry`/
`with_images`/`image_ids` helpers. `mod.rs` re-exports every module's
public items under `library::`, including the `pub(crate)`
`test_support` module `repairs.rs` reads its fixtures from, so no file
outside `library` needed a change.
The previous commit split develop.rs the same way; taken alone it left
dr-ui without library.rs, so that intermediate commit does not build on
its own. This one restores it.
dtourolle