formualizer-eval 0.7.0

High-performance Arrow-backed Excel formula engine with dependency graph and incremental recalculation
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
//! Named-reference span support: acceptance, dirty precision, name lifecycle
//! invalidation (define/update/delete), cross-sheet and shadowed resolution,
//! the InternalDependency guard, and precise fallback reasons.
//!
//! Defined names canonicalize by identity (raw text participates in the
//! template fingerprint) and resolve to all-absolute read regions per cell at
//! ingest. These tests pin (counter-style, never wall time):
//!
//! - workbook-scoped named-range/named-cell families promote to spans and
//!   evaluate to legacy-identical values, before and after edits;
//! - edits inside the resolved named region re-evaluate the span, edits
//!   outside do not;
//! - define/update/delete of a name demotes name-dependent spans so their
//!   cells re-ingest and re-resolve exactly like legacy formulas (the
//!   load-bearing invalidation hook: without it, a span keeps a stale
//!   resolved read region and misses edits inside the new region);
//! - sheet-scope shadowing resolves per placement sheet without
//!   cross-contaminating span families on other sheets;
//! - a name covering the family's own result column falls back
//!   (InternalDependency), and Literal-definition/undefined names fall back
//!   with `UnsupportedNamedReference`.

use std::sync::Arc;

use formualizer_common::LiteralValue;
use formualizer_parse::parser::parse;

use crate::engine::named_range::{NameScope, NamedDefinition};
use crate::engine::{
    Engine, EvalConfig, FormulaIngestBatch, FormulaIngestRecord, FormulaPlaneMode,
};
use crate::reference::{CellRef, Coord, RangeRef};
use crate::test_workbook::TestWorkbook;

const SHEET: &str = "Sheet1";
/// Must be >= 100 (`MIN_PROMOTED_NON_CONSTANT_SPAN_CELLS`).
const ROWS: u32 = 120;
const FIRST_ROW: u32 = 2;
const LAST_ROW: u32 = ROWS + 1;

fn engine_with_mode(mode: FormulaPlaneMode) -> Engine<TestWorkbook> {
    let cfg = EvalConfig::default().with_formula_plane_mode(mode);
    Engine::new(TestWorkbook::default(), cfg)
}

fn cell_ref(engine: &mut Engine<TestWorkbook>, sheet: &str, row1: u32, col1: u32) -> CellRef {
    let sheet_id = engine.graph.sheet_id_mut(sheet);
    CellRef::new(sheet_id, Coord::new(row1 - 1, col1 - 1, true, true))
}

fn range_def(
    engine: &mut Engine<TestWorkbook>,
    sheet: &str,
    start_row1: u32,
    start_col1: u32,
    end_row1: u32,
    end_col1: u32,
) -> NamedDefinition {
    let start = cell_ref(engine, sheet, start_row1, start_col1);
    let end = cell_ref(engine, sheet, end_row1, end_col1);
    NamedDefinition::Range(RangeRef::new(start, end))
}

fn record(
    engine: &mut Engine<TestWorkbook>,
    row: u32,
    col: u32,
    formula: &str,
) -> FormulaIngestRecord {
    let ast = parse(formula).unwrap_or_else(|err| panic!("parse {formula}: {err}"));
    let ast_id = engine.intern_formula_ast(&ast);
    FormulaIngestRecord::new(row, col, ast_id, Some(Arc::<str>::from(formula)))
}

fn ingest_column(
    engine: &mut Engine<TestWorkbook>,
    sheet: &str,
    col: u32,
    formula_for_row: impl Fn(u32) -> String,
) -> crate::engine::FormulaIngestReport {
    let mut records = Vec::with_capacity(ROWS as usize);
    for row in FIRST_ROW..=LAST_ROW {
        let formula = formula_for_row(row);
        records.push(record(engine, row, col, &formula));
    }
    engine
        .ingest_formula_batches(vec![FormulaIngestBatch::new(sheet, records)])
        .expect("ingest formulas")
}

fn literal_eq(a: &LiteralValue, b: &LiteralValue) -> bool {
    fn as_num(v: &LiteralValue) -> Option<f64> {
        match v {
            LiteralValue::Number(n) => Some(*n),
            LiteralValue::Int(i) => Some(*i as f64),
            LiteralValue::Boolean(b) => Some(if *b { 1.0 } else { 0.0 }),
            _ => None,
        }
    }
    match (as_num(a), as_num(b)) {
        (Some(x), Some(y)) => {
            let scale = x.abs().max(y.abs()).max(1.0);
            (x - y).abs() <= scale * 1e-9
        }
        _ => a == b,
    }
}

fn assert_column_parity(
    label: &str,
    sheet: &str,
    col: u32,
    auth: &Engine<TestWorkbook>,
    off: &Engine<TestWorkbook>,
) {
    for row in FIRST_ROW..=LAST_ROW {
        let got = auth.get_cell_value(sheet, row, col);
        let expected = off.get_cell_value(sheet, row, col);
        let equal = match (&got, &expected) {
            (Some(a), Some(b)) => literal_eq(a, b),
            (a, b) => a == b,
        };
        assert!(
            equal,
            "{label}: value mismatch at {sheet}!R{row}C{col}: auth={got:?} off={expected:?}"
        );
    }
}

fn set_value(engine: &mut Engine<TestWorkbook>, sheet: &str, row: u32, col: u32, value: f64) {
    engine
        .action_atomic_journal(format!("edit {sheet}!R{row}C{col}"), |tx| {
            tx.set_cell_value(sheet, row, col, LiteralValue::Number(value))?;
            Ok(())
        })
        .unwrap();
}

/// Data column B carries `row` as value; A carries `10*row`.
fn seed_named_workbook(engine: &mut Engine<TestWorkbook>) {
    for row in FIRST_ROW..=LAST_ROW {
        engine
            .set_cell_value(SHEET, row, 2, LiteralValue::Number(row as f64))
            .unwrap();
        engine
            .set_cell_value(SHEET, row, 1, LiteralValue::Number(10.0 * row as f64))
            .unwrap();
    }
    let def = range_def(engine, SHEET, FIRST_ROW, 2, LAST_ROW, 2);
    engine
        .define_name("Data", def, NameScope::Workbook)
        .unwrap();
}

/// (a) Acceptance + first-eval/after-edit value parity, counter-pinned.
#[test]
fn named_range_family_promotes_to_span_with_value_parity() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        seed_named_workbook(engine);
    }
    let report = ingest_column(&mut auth, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    let _ = ingest_column(&mut off, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));

    assert_eq!(
        report.shadow_accepted_span_cells,
        u64::from(ROWS),
        "named-range family must span; histogram: {:?}",
        report.fallback_reasons
    );
    assert_eq!(report.shadow_fallback_cells, 0);
    assert!(report.shadow_spans_created >= 1);
    assert_eq!(auth.baseline_stats().formula_plane_active_span_count, 1);

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("first eval", SHEET, 3, &auth, &off);

    // Edit inside the named region and a relative precedent; values must stay
    // legacy-identical.
    for engine in [&mut auth, &mut off] {
        set_value(engine, SHEET, 10, 2, 5_000.0);
        set_value(engine, SHEET, 11, 1, 7_000.0);
    }
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("after edits", SHEET, 3, &auth, &off);
}

/// (b) Dirty precision: edits inside the resolved named region re-evaluate
/// the span; edits outside do not.
#[test]
fn named_range_edit_dirty_precision_is_region_bounded() {
    let mut engine = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    seed_named_workbook(&mut engine);
    let report = ingest_column(&mut engine, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    assert_eq!(report.shadow_accepted_span_cells, u64::from(ROWS));

    engine.evaluate_all().unwrap();
    let first = engine
        .last_formula_plane_span_eval_report()
        .expect("first eval must run the authoritative span pass");
    assert_eq!(first.span_eval_placement_count, u64::from(ROWS));

    // Inside the named region: every placement reads it.
    set_value(&mut engine, SHEET, 10, 2, 5_000.0);
    engine.evaluate_all().unwrap();
    let inside = engine
        .last_formula_plane_span_eval_report()
        .expect("edit inside named region must produce span work");
    assert_eq!(inside.span_eval_placement_count, u64::from(ROWS));

    // Relative precedent A11: exactly one placement reads it.
    set_value(&mut engine, SHEET, 11, 1, 7_000.0);
    engine.evaluate_all().unwrap();
    let relative = engine
        .last_formula_plane_span_eval_report()
        .expect("edit of a relative precedent must produce span work");
    assert_eq!(relative.span_eval_placement_count, 1);

    // Outside every read region (column F): no span recompute.
    set_value(&mut engine, SHEET, 10, 6, 9_999.0);
    engine.evaluate_all().unwrap();
    let outside_placements = engine
        .last_formula_plane_span_eval_report()
        .map(|report| report.span_eval_placement_count)
        .unwrap_or(0);
    assert_eq!(
        outside_placements, 0,
        "edit outside all read regions must not re-evaluate the span"
    );
}

/// (c) THE load-bearing invalidation test: update_name to a different region
/// must demote the span so cells re-resolve. Without the hook the span keeps
/// the stale resolved region and misses edits inside the new region.
#[test]
fn update_name_to_new_region_invalidates_spans_and_tracks_new_region() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        seed_named_workbook(engine);
        // Alternate data column D for the re-pointed name.
        for row in FIRST_ROW..=LAST_ROW {
            engine
                .set_cell_value(SHEET, row, 4, LiteralValue::Number(1_000.0 + row as f64))
                .unwrap();
        }
    }
    let report = ingest_column(&mut auth, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    let _ = ingest_column(&mut off, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    assert_eq!(report.shadow_accepted_span_cells, u64::from(ROWS));

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("before update_name", SHEET, 3, &auth, &off);

    for engine in [&mut auth, &mut off] {
        let def = range_def(engine, SHEET, FIRST_ROW, 4, LAST_ROW, 4);
        engine
            .update_name("Data", def, NameScope::Workbook)
            .unwrap();
    }
    // The span resolved the old region; the invalidation hook must demote it.
    assert_eq!(
        auth.baseline_stats().formula_plane_active_span_count,
        0,
        "update_name must demote the name-dependent span"
    );
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("after update_name", SHEET, 3, &auth, &off);

    // Edit inside the NEW region (column D): values must track it.
    for engine in [&mut auth, &mut off] {
        set_value(engine, SHEET, 20, 4, 50_000.0);
    }
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("edit inside re-pointed region", SHEET, 3, &auth, &off);
}

/// (d) define_name of a sheet-scoped name AFTER ingest that shadows a
/// workbook-scoped name already resolved by spans on that sheet.
#[test]
fn sheet_scoped_define_after_ingest_invalidates_workbook_resolved_spans() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        seed_named_workbook(engine);
        for row in FIRST_ROW..=LAST_ROW {
            engine
                .set_cell_value(SHEET, row, 4, LiteralValue::Number(2_000.0 + row as f64))
                .unwrap();
        }
    }
    let report = ingest_column(&mut auth, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    let _ = ingest_column(&mut off, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    assert_eq!(report.shadow_accepted_span_cells, u64::from(ROWS));

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("before shadowing define", SHEET, 3, &auth, &off);

    for engine in [&mut auth, &mut off] {
        let sheet_id = engine.graph.sheet_id_mut(SHEET);
        let def = range_def(engine, SHEET, FIRST_ROW, 4, LAST_ROW, 4);
        engine
            .define_name("Data", def, NameScope::Sheet(sheet_id))
            .unwrap();
    }
    assert_eq!(
        auth.baseline_stats().formula_plane_active_span_count,
        0,
        "shadowing define must demote spans that resolved through workbook scope"
    );
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("after shadowing define", SHEET, 3, &auth, &off);

    // Edits inside the shadowed (sheet-scoped) region must flow identically.
    for engine in [&mut auth, &mut off] {
        set_value(engine, SHEET, 30, 4, 77_000.0);
    }
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("edit inside shadowed region", SHEET, 3, &auth, &off);
}

/// (e) delete_name: cells fall back to legacy and evaluate to #NAME? exactly
/// like the Off-mode ground truth.
#[test]
fn delete_name_falls_back_to_name_error_parity() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        seed_named_workbook(engine);
    }
    let report = ingest_column(&mut auth, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    let _ = ingest_column(&mut off, SHEET, 3, |r| format!("=SUM(Data)+A{r}"));
    assert_eq!(report.shadow_accepted_span_cells, u64::from(ROWS));

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();

    for engine in [&mut auth, &mut off] {
        engine.delete_name("Data", NameScope::Workbook).unwrap();
    }
    assert_eq!(auth.baseline_stats().formula_plane_active_span_count, 0);
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("after delete_name", SHEET, 3, &auth, &off);

    // And the parity target itself must be #NAME?, not a stale number.
    match off.get_cell_value(SHEET, FIRST_ROW, 3) {
        Some(LiteralValue::Error(err)) => {
            assert_eq!(err.kind, formualizer_common::ExcelErrorKind::Name)
        }
        other => panic!("expected #NAME? ground truth after delete_name, got {other:?}"),
    }
}

/// (f) Named CELL definition and a named range defined on ANOTHER sheet than
/// the formulas (cross-sheet resolution), counter-pinned with dirty checks.
#[test]
fn named_cell_and_cross_sheet_named_range_span_and_track_edits() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        engine.add_sheet("Sheet2").unwrap();
        for row in FIRST_ROW..=LAST_ROW {
            engine
                .set_cell_value("Sheet2", row, 2, LiteralValue::Number(row as f64))
                .unwrap();
            engine
                .set_cell_value(SHEET, row, 1, LiteralValue::Number(3.0 * row as f64))
                .unwrap();
        }
        engine
            .set_cell_value("Sheet2", 1, 5, LiteralValue::Number(41.5))
            .unwrap();
        let remote = range_def(engine, "Sheet2", FIRST_ROW, 2, LAST_ROW, 2);
        engine
            .define_name("RemoteData", remote, NameScope::Workbook)
            .unwrap();
        let cell = cell_ref(engine, "Sheet2", 1, 5);
        engine
            .define_name(
                "RemoteCell",
                NamedDefinition::Cell(cell),
                NameScope::Workbook,
            )
            .unwrap();
    }
    let report = ingest_column(&mut auth, SHEET, 3, |r| {
        format!("=SUM(RemoteData)+RemoteCell*2+A{r}")
    });
    let _ = ingest_column(&mut off, SHEET, 3, |r| {
        format!("=SUM(RemoteData)+RemoteCell*2+A{r}")
    });
    assert_eq!(
        report.shadow_accepted_span_cells,
        u64::from(ROWS),
        "cross-sheet named range + named cell must span; histogram: {:?}",
        report.fallback_reasons
    );

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("cross-sheet first eval", SHEET, 3, &auth, &off);

    // Edit inside the remote named region and the named cell.
    for engine in [&mut auth, &mut off] {
        set_value(engine, "Sheet2", 15, 2, 12_345.0);
        set_value(engine, "Sheet2", 1, 5, 100.25);
    }
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("cross-sheet after edits", SHEET, 3, &auth, &off);
}

/// Section-2 subtlety: the same name string resolving differently per sheet
/// (sheet-scope shadowing) must not cross-contaminate span families.
#[test]
fn shadowed_names_on_two_sheets_resolve_per_sheet_without_cross_contamination() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        engine.add_sheet("Sheet2").unwrap();
        for row in FIRST_ROW..=LAST_ROW {
            engine
                .set_cell_value(SHEET, row, 2, LiteralValue::Number(row as f64))
                .unwrap();
            engine
                .set_cell_value("Sheet2", row, 2, LiteralValue::Number(1_000.0 + row as f64))
                .unwrap();
            engine
                .set_cell_value(SHEET, row, 1, LiteralValue::Number(row as f64))
                .unwrap();
            engine
                .set_cell_value("Sheet2", row, 1, LiteralValue::Number(row as f64))
                .unwrap();
        }
        // Workbook-scoped X -> Sheet1!B; sheet-scoped X on Sheet2 -> Sheet2!B.
        let workbook = range_def(engine, SHEET, FIRST_ROW, 2, LAST_ROW, 2);
        engine
            .define_name("X", workbook, NameScope::Workbook)
            .unwrap();
        let sheet2_id = engine.graph.sheet_id_mut("Sheet2");
        let shadowed = range_def(engine, "Sheet2", FIRST_ROW, 2, LAST_ROW, 2);
        engine
            .define_name("X", shadowed, NameScope::Sheet(sheet2_id))
            .unwrap();
    }
    for sheet in [SHEET, "Sheet2"] {
        let report_auth = ingest_column(&mut auth, sheet, 3, |r| format!("=SUM(X)+A{r}"));
        let _ = ingest_column(&mut off, sheet, 3, |r| format!("=SUM(X)+A{r}"));
        assert_eq!(
            report_auth.shadow_accepted_span_cells,
            u64::from(ROWS),
            "{sheet}: shadowed-name family must span; histogram: {:?}",
            report_auth.fallback_reasons
        );
    }
    assert_eq!(auth.baseline_stats().formula_plane_active_span_count, 2);

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("shadowed Sheet1", SHEET, 3, &auth, &off);
    assert_column_parity("shadowed Sheet2", "Sheet2", 3, &auth, &off);

    // The two sheets must see different sums (proof the resolutions differ).
    let s1 = auth.get_cell_value(SHEET, FIRST_ROW, 3);
    let s2 = auth.get_cell_value("Sheet2", FIRST_ROW, 3);
    assert_ne!(s1, s2, "shadowed name resolutions must differ per sheet");

    // An edit inside Sheet2's shadowed region must not touch Sheet1 values.
    for engine in [&mut auth, &mut off] {
        set_value(engine, "Sheet2", 40, 2, 99_000.0);
    }
    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("shadowed Sheet1 after Sheet2 edit", SHEET, 3, &auth, &off);
    assert_column_parity("shadowed Sheet2 after edit", "Sheet2", 3, &auth, &off);
}

/// (g) Self-overlap: a name whose region covers the family's own result
/// column must reject with InternalDependency and stay value-identical to
/// the Off-mode ground truth.
#[test]
fn name_covering_own_result_column_rejects_with_internal_dependency() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        for row in FIRST_ROW..=LAST_ROW {
            engine
                .set_cell_value(SHEET, row, 2, LiteralValue::Number(row as f64))
                .unwrap();
        }
        // Covers column C rows 2..=LAST_ROW: the formulas' own result region.
        let def = range_def(engine, SHEET, FIRST_ROW, 3, LAST_ROW, 3);
        engine
            .define_name("SelfRegion", def, NameScope::Workbook)
            .unwrap();
    }
    let report = ingest_column(&mut auth, SHEET, 3, |r| format!("=SUM(SelfRegion)*0+B{r}"));
    let _ = ingest_column(&mut off, SHEET, 3, |r| format!("=SUM(SelfRegion)*0+B{r}"));

    assert_eq!(report.shadow_accepted_span_cells, 0);
    assert_eq!(
        report
            .fallback_reasons
            .get("InternalDependency")
            .copied()
            .unwrap_or(0),
        u64::from(ROWS),
        "histogram: {:?}",
        report.fallback_reasons
    );
    assert_eq!(auth.baseline_stats().formula_plane_active_span_count, 0);

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("self-overlap", SHEET, 3, &auth, &off);
}

/// (h) Literal-definition and undefined names fall back with the precise
/// `UnsupportedNamedReference` reason, values legacy-identical.
#[test]
fn literal_and_undefined_names_fall_back_with_precise_reason() {
    let mut auth = engine_with_mode(FormulaPlaneMode::AuthoritativeExperimental);
    let mut off = engine_with_mode(FormulaPlaneMode::Off);
    for engine in [&mut auth, &mut off] {
        for row in FIRST_ROW..=LAST_ROW {
            engine
                .set_cell_value(SHEET, row, 1, LiteralValue::Number(row as f64))
                .unwrap();
        }
        engine
            .define_name(
                "LitName",
                NamedDefinition::Literal(LiteralValue::Number(2.5)),
                NameScope::Workbook,
            )
            .unwrap();
    }

    // Literal-definition name -> column C.
    let literal_report = ingest_column(&mut auth, SHEET, 3, |r| format!("=LitName+A{r}"));
    let _ = ingest_column(&mut off, SHEET, 3, |r| format!("=LitName+A{r}"));
    assert_eq!(literal_report.shadow_accepted_span_cells, 0);
    assert_eq!(
        literal_report
            .fallback_reasons
            .get("UnsupportedNamedReference")
            .copied()
            .unwrap_or(0),
        u64::from(ROWS),
        "histogram: {:?}",
        literal_report.fallback_reasons
    );

    // Undefined name -> column D.
    let undefined_report = ingest_column(&mut auth, SHEET, 4, |r| format!("=NoSuchName+A{r}"));
    let _ = ingest_column(&mut off, SHEET, 4, |r| format!("=NoSuchName+A{r}"));
    assert_eq!(undefined_report.shadow_accepted_span_cells, 0);
    assert_eq!(
        undefined_report
            .fallback_reasons
            .get("UnsupportedNamedReference")
            .copied()
            .unwrap_or(0),
        u64::from(ROWS),
        "histogram: {:?}",
        undefined_report.fallback_reasons
    );

    assert_eq!(auth.baseline_stats().formula_plane_active_span_count, 0);

    auth.evaluate_all().unwrap();
    off.evaluate_all().unwrap();
    assert_column_parity("literal-name column", SHEET, 3, &auth, &off);
    assert_column_parity("undefined-name column", SHEET, 4, &auth, &off);

    // Ground-truth sanity: literal-name cells are numeric, undefined-name
    // cells are #NAME?.
    match off.get_cell_value(SHEET, FIRST_ROW, 3) {
        Some(LiteralValue::Number(n)) => assert!((n - (2.5 + FIRST_ROW as f64)).abs() < 1e-9),
        other => panic!("expected numeric literal-name ground truth, got {other:?}"),
    }
    match off.get_cell_value(SHEET, FIRST_ROW, 4) {
        Some(LiteralValue::Error(err)) => {
            assert_eq!(err.kind, formualizer_common::ExcelErrorKind::Name)
        }
        other => panic!("expected #NAME? ground truth for undefined name, got {other:?}"),
    }
}