# Tasks: table-formulas (roadmap 40)

Spec: `spec.md`. Ordered tasks depend on preceding tasks only; each finishes with independently runnable behavior tests.

**First tool call rule:** after at most three focused reads, write FIRST OWNS file in SECOND tool call: compiling stub plus one failing behavior test, then make it pass. New paths below are explicitly marked new; other paths verified in source on 2026-10-21.
**Standing VERIFY:** `export PATH="$HOME/.cargo/bin:$PATH"`; `cargo test -p <pkg>`; `cargo clippy -p <pkg> --all-targets -- -D warnings`; `rustfmt --edition 2024 <owned Rust files>`; UI tasks also `cargo xtask i18n` and inspect snapshot PNG at 1440x900 Mocha/Latte. Final task: `cargo xtask ci`. These are FUTURE implementation checks; documentation author runs no cargo.
**Standing DO NOT:** edit outside OWNS, mutate Git, add dependencies, blanket lint allows, panic/unchecked input indexing, IO during paint, overwrite malformed user data, bypass atomic vault writes, `cargo fmt --all`. No new crate planned: no root Cargo.toml or xtask/src/layers.rs edits required. If implementation introduces a crate, stop for scope approval then explicitly own root Cargo.toml and xtask/src/layers.rs registration before compiling.

## Phase 1
- [x] 1. Bounded formula grammar and cell dependency evaluation (brief `briefs/27-table-formula-model.md`).

  OWNS: `crates/blocks/src/table_formulas/mod.rs` (new, first write), `crates/blocks/src/table_formulas/parse.rs` (new), `crates/blocks/src/table_formulas/eval.rs` (new), `crates/blocks/src/lib.rs` (module/export and errors), unit tests in new modules

  FILES TO OPEN: `spec.md` D1/D2, `crates/blocks/src/lib.rs`, `crates/bases/src/eval/ops.rs` (finite number handling reference only), `crates/ui-egui/src/views/note_view/blocks/table.rs`

  GOAL: `evaluate(cells: &[Vec<String>]) -> Result<Evaluation>` with stable cell diagnostics; parse formulas into bounded AST, compute dependency DAG iteratively, no scripts or IO. Implement D1 coordinate/numeric/aggregate semantics and every D2 resource cap.

  TESTS: Arithmetic precedence/unary; A1 body coords; ranges; each aggregate including empty/text; cycles and propagation; nonfinite/divzero/out-of-bounds; depth/formula/cell/edge/operation caps; deterministic results; raw cell strings unchanged.

  VERIFY: standing, `-p notescraft-blocks`.

  DO NOT: Add dependency or reuse Bases expression grammar as if A1 were note property syntax.

## Phase 2
- [ ] 2. Shared table extraction and read-only command.

  OWNS: `crates/blocks/src/table_formulas/table.rs` (new), `crates/blocks/src/table_formulas/mod.rs` (declaration/export), `crates/engine/src/block_edit/formulas.rs` (new), `crates/engine/src/block_edit/mod.rs` (module/registration), `crates/engine/src/ai/assistant_gate.rs`, `crates/engine/tests/core_commands.rs` (CORE_IDS), `crates/engine/tests/table_formulas.rs` (new)

  FILES TO OPEN: `spec.md` D3, `crates/ui-egui/src/views/note_view/blocks/table.rs`, `crates/ui-egui/src/views/note_view/blocks/table/edit.rs`, `crates/blocks/src/parse.rs`

  GOAL: Extract shared cell tokenizer/ranges and opt-in marker detection; implement table.formulas.evaluate JSON contract; reject unmarked table as not_enabled, malformed/table_index bad params with zero writes.

  TESTS: Escaped/code-span pipes; Unicode/CRLF/short row normalization; marked/unmarked; malformed marker; multiple tables/index bounds; readonly works; engine coordinates equal pure fixtures; disk untouched.

  VERIFY: standing, `-p notescraft-engine`.

  DO NOT: Materialize computed values or alter source.

## Phase 3
- [ ] 3. Visual formula rendering and editing.

  OWNS: `crates/ui-egui/src/views/note_view/blocks/table/formulas.rs` (new), `crates/ui-egui/src/views/note_view/blocks/table.rs` (module and shared extraction), `crates/ui-egui/src/views/note_view/blocks/table/edit.rs`, `crates/ui-egui/src/text/views/blocks.rs`, `crates/i18n/locales/en.toml` (append formula keys), tests in owned table modules

  FILES TO OPEN: `spec.md` D3, `crates/ui-egui/src/views/note_view/blocks/table.rs`, `crates/ui-egui/src/views/note_view/blocks/table/edit.rs`

  GOAL: Render computed display/error tooltip only when opted in; exact-source cache; raw formula editing with existing NoteEdit/undo; confirm structural edits and preserve references; render literal code uncomputed.

  TESTS: UI values versus formula editor; edit/undo raw bytes; unmarked snapshot unchanged; structural confirm/cancel; source/engine coordinate parity; unchanged frame evaluation counter zero; both-theme screenshot.

  VERIFY: standing, `-p notescraft-ui-egui`.

  DO NOT: Rewrite refs, write result values automatically or export executable CSV silently.

## Phase 4
- [ ] 4. Compatibility corpus and status.

  OWNS: `crates/engine/tests/table_formulas.rs`, `ROADMAP.md`, `docs/ARCHITECTURE.md`, `docs/CODE-MAP.md`, `specs/plugins-parity/roadmap.md` (rank40)

  FILES TO OPEN: `spec.md` acceptance criteria

  GOAL: Close acceptance with hostile-input and source preservation fixtures; document NotesCraft-only opt-in syntax, f64 limits and raw export.

  TESTS: All caps and error codes; marker remains after edit; unmarked tables unaffected; source byte checks.

  VERIFY: standing, `-p notescraft-engine`.

  DO NOT: Claim Excel/Advanced Tables formula compatibility.