notescraft/specs/plugins-parity/version-diff/tasks.md

Tasks: note visual diff and time-machine slider (roadmap 27)

One task = one agent (specs/agents/opencode-runbook.md). Spec: spec.md. Rules: AGENTS.md, docs/CODE-MAP.md. First tool call rule: after at most three reads, write the first OWNS file in your SECOND tool call (compiling stub + ONE failing test), then make it pass. Standing VERIFY: export PATH="$HOME/.cargo/bin:$PATH"; cargo test -p <pkg>; cargo clippy -p <pkg> --all-targets -- -D warnings; rustfmt --edition 2024 <owned files>; UI tasks add cargo xtask i18n; last task of a phase adds cargo xtask layers and cargo xtask tree. Standing DO NOT: edit files outside OWNS, git state, cargo fmt --all; add allow; unwrap/expect/panic/[i]/[a..b] on input-derived data; add a dependency.

Owner/lead step 0

Answer Q1 and Q2. If Q2 = similar, the owner adds it and task 1 shrinks to a wrapper.

Phase 1 - pure crate

• 1. Crate notescraft-textdiff (brief briefs/14-textdiff-crate.md). Crate registration is part of this task: OWNS: crates/textdiff/Cargo.toml, crates/textdiff/src/lib.rs, crates/textdiff/src/tokens.rs, crates/textdiff/src/myers.rs, crates/textdiff/tests/word_diff.rs; registration edits: root Cargo.toml (one line in [workspace.dependencies]: notescraft-textdiff = { path = "crates/textdiff" }, and the member glob already covers crates/*), xtask/src/layers.rs (("textdiff", Class::Layer(0)) in L0 of TABLE), and any layers test in xtask/ that counts crates (grep TABLE). FILES TO OPEN: spec.md D1, crates/tasks/Cargo.toml (manifest to copy: [lints] workspace = true, publish = false), crates/tasks/src/lib.rs (#![deny(...)] header and Error style), xtask/src/layers.rs:36-60. GOAL: D1 API; Error::TooLarge. TESTS: reproduction property (1 000 pseudo-random pairs from a fixed LCG seed, no rand dep), one changed word, insertion at start/end, empty old/new, both empty, CRLF, emoji, 2 MiB pair returns Ok or TooLarge in < 500 ms (#[ignore] perf), limits boundaries. VERIFY: standing -p notescraft-textdiff + cargo xtask layers. DO NOT: depend on any crate except thiserror; touch other crates.

Phase 2 - engine

• 2. history.diff. OWNS: crates/engine/Cargo.toml (one dependency line notescraft-textdiff = { workspace = true }), crates/engine/src/commands.rs (new spec + fn next to history_list), crates/engine/src/ai/assistant_gate.rs, crates/engine/tests/core_commands.rs, crates/engine/tests/history_diff.rs. FILES TO OPEN: spec.md D2, crates/engine/src/commands.rs:110-125,310-330, crates/engine/src/vault/snapshots/mod.rs, crates/engine/tests/common/mod.rs. GOAL: D2 table; against snapshot or current (buffer text if open, else file). TESTS: two snapshots (use snapshot_note_at through the test helper pattern in snapshots/mod.rs tests), diff counts, unknown id -> error, current vs open buffer, spans cap sets truncated. VERIFY: standing + --test history_diff --test core_commands. DO NOT: change history.list output; touch UI.

Phase 3 - UI

• 3. Word diff pane (pure paint + cache). OWNS: crates/ui-egui/src/views/versions_view/word_diff.rs, crates/ui-egui/tests/word_diff_view.rs. FILES TO OPEN: crates/ui-egui/src/views/diff_view/render.rs (colour tokens used), crates/ui-egui/src/views/versions_view/mod.rs, crates/ui-egui/src/views/share_dialog/mod.rs (worker pattern). GOAL: paint(ui, tokens, &[Span]) wrapped rich text; DiffJob worker with 120 ms debounce and (id, against) cache. TESTS: kittest paints add/del spans without panic; cache returns without new job; 5 000 spans bounded. VERIFY: standing. DO NOT: hex colours; engine calls on the UI thread.
• 4. Slider and wiring. OWNS: crates/ui-egui/src/views/versions_view/slider.rs, crates/ui-egui/src/views/versions_view/mod.rs (hook lines), crates/ui-egui/src/text/versions_view.rs (+ matching keys at END of the [ui.versions] block in crates/i18n/locales/en.toml), crates/ui-egui/tests/versions_slider.rs. FILES TO OPEN: spec.md D3, crates/ui-egui/src/views/versions_view/mod.rs, crates/ui-egui/src/shell/app/window/views.rs:130-160 (how VersionsAction is handled), .claude/skills/notescraft-egui-screen/. GOAL: proportional ticks, keyboard, "vs previous / vs now" toggle (Switch widget), Restore button emits existing VersionsAction::Restore. TESTS: kittest: ticks count == snapshots+1, click tick selects it, arrow keys move, Restore emits the right id, too-large message shown. VERIFY: standing + cargo xtask i18n + snapshot PNG read. DO NOT: remove the row list; raw egui widgets.
• 5. Docs and status. OWNS: ROADMAP.md, docs/ARCHITECTURE.md (new crate), docs/CODE-MAP.md, specs/plugins-parity/roadmap.md (mark 27). VERIFY: cargo xtask ci.