[brzuchal]

Summary

Polish formula entry and display, as a dialect for the formula languages from #443. With the interface in Polski, =JEŻELI(PRAWDA;SUMA(1,5;2,25);#N/D) and =suma.jeżeli(A1:A3;">1") work as typed, and files keep canonical English formulas.

Draft, stacked on two open PRs, as suggested by @quantmind-br in #430 (comment):

• M12: formulas in German, Brazilian Portuguese, Russian and French, full Spanish table #443 (a1256e5, untouched) — the dialect mechanism;
• i18n: add Polish (pl) interface #650 (b993940) — the Polish interface, which this branch merges so Language::Pl exists.

Once both are on main, only the last commit (63d19b8) is new. I'll rebase whenever needed.

• crates/formula/src/input/pl.rs: a Dialect with 429 function names, ; arguments, decimal comma, \ and ; in array constants, PRAWDA/FAŁSZ, the ten error values and the five structured-reference specifiers.
• FormulaLocale::Pl in ALL and dialect(); Language::Pl => FormulaLocale::Pl in formula_locale() (this also resolves the exhaustive-match trap between M12: formulas in German, Brazilian Portuguese, Russian and French, full Spanish table #443 and i18n: add Polish (pl) interface #650).

Where the words come from

Question 1 in #430 (which sources are acceptable) is still open for the maintainers, so here is exactly what was done:

• Observed in a licensed Excel for the web with a Polish interface and regional format, on 2026-10-12, in synthetic workbooks written for this purpose. Every function GridCraft knows was entered in canonical form (once plain, once with _xlfn.), and FORMULATEXT showed how Polish Excel displays it. This gave all 514 functions: 429 with a Polish name, 85 that keep the English one.
• Also observed: separators (=SUMA(1;2), =1,5+1, {1\2\3}, {1;2;3}), booleans, the errors #ZERO!, #DZIEL/0!, #ARG!, #ADR!, #NAZWA?, #LICZBA!, #N/D, #OBL!, #ROZLANIE!, and the specifiers #Wszystko, #Dane, #Nagłówki, #Sumy.
• From Microsoft's pl-pl help pages, not observed: #POBIERANIE_DANYCH and #Ten wiersz (Excel shows the @ short form).
• Not used: LibreOffice, Gnumeric or HyperFormula translations.
• Not committed: any file produced by Excel.

Two things the observation showed that the help pages get wrong or leave open:

• Polish Excel shows #N/D, while the pl-pl ERROR.TYPE page prints #N/D!.
• It keeps LAMBDA, LET, MAP, REDUCE, SCAN, MAKEARRAY and BYCOL in English while translating BYROW as WIERSZAMI. The table follows what Excel does.

JIS, EUROCONVERT and ADD2 are unknown to Excel for the web and keep their English names.

I am a native Polish speaker. The table was built with Claude (AI agent) from the observations above; no second native speaker has reviewed it yet.

Tests

• crates/formula/tests/localized_input.rs: Pl in LOCALIZED. New Polish entry/display cases cover IF/VLOOKUP/#N/D, arrays with \, a table specifier with ;, IFERROR/XLOOKUP and ILE.WIERSZY(Tabela1[#Wszystko]), plus lower-case suma.jeżeli/fałsz/złącz.tekst. The round-trip and table checks pick up Pl through FormulaLocale::ALL.
• crates/calc: formula_language_tables_only_name_functions_the_engine_knows passes with the Polish table.
• crates/ui-egui/tests/formula_locale.rs: the i18n: add Polish (pl) interface #650 test that pinned Polish to canonical English is now polish_interface_enters_and_shows_polish_formulas.

Ran locally on Rust 1.95.0:

• cargo test -p gridcraft-formula passes.
• The calc test above passes.
• cargo test -p gridcraft-ui-egui --test formula_locale --test interaction passes (11 + 25).
• cargo fmt --all --check and cargo clippy -p gridcraft-formula --all-targets -- -D warnings are clean.
• cargo test -p gridcraft-ui-egui --lib has one failure that is already on main: missing French: Different First Page (fix(i18n): French labels name unrelated actions and omit two required translations #529).

I did not run the full cargo xtask ci.

Not in this PR

• docs/formula-input.md, docs/localization-parity.md and ROADMAP.md still describe Polish formulas as English. I'll update them once the base PRs settle, to avoid three-way doc conflicts.
• Number and date formats (M12: regional formats (typed and displayed numbers, dates and times) #447 territory).

[yrrh]

I cross-checked the 429 names in pl.rs against Microsoft's own pl-pl documentation (the alphabetical function list plus each function's pl-pl page, fetched 2026-10-14). 392 match outright, and almost all of the remaining differences are inconsistencies inside Microsoft's pages rather than in this table (e.g. the IMCSC/IMSECH pages are titled CSC.LICZBA.ZESP but their syntax lines say CSC.LICZBY.ZESP, the *B variants only show up on the alphabetical list, and the dynamic-array pages mix English titles with Polish examples). So the table looks solid. Two entries are worth a second look in a desktop Polish Excel, because the docs disagree with what the table has:

• PERCENTOF: the table has ODSETEK; the pl-pl page is titled "PROCENT, funkcja" and its example uses =PROCENT(. (https://support.microsoft.com/pl-pl/excel/functions/percentof-function)
• MAP: the table keeps MAP in English; the pl-pl page is titled "Funkcja MAPUJ", although its examples use =MAP(. (https://support.microsoft.com/pl-pl/excel/functions/map-function) The same question applies to BYCOL, since BYROW is WIERSZAMI here.

Both are recent functions whose names Microsoft may have changed between the web and desktop builds, so the observation in Excel for the web might simply differ from the current desktop release. Not blocking, just flagging it for whoever can check against a desktop Excel 365 in Polish.

For what it's worth, the Polish names Microsoft documents for functions the engine doesn't have yet (WEŹDANETABELI, DANE.CZASU.RZECZ, OBRAZ, HISTORIA.AKCJI, PRZETŁUMACZ, WYKRYJJĘZYK, WYWOŁAJ, REJESTR.KOD) are correctly left out, given formula_language_tables_only_name_functions_the_engine_knows.

[brzuchal]

@yrrh thanks for going through all 429 names against the pl-pl pages. That is a useful independent check.

I rechecked the flagged entries today in Excel for the web (excel.cloud.microsoft) with a Polish interface, in a fresh workbook. Excel confirms the table:

Canonical	In the table	Typed in Polish Excel for the web	Result
PERCENTOF	ODSETEK	=ODSETEK(1;4)	0,25, with ODSETEK's Polish argument help ("podzbiór_danych; wszystkie_dane")
		=PROCENT(1;4)	#NAZWA?; autocomplete offers only PROCENT.POZYCJA (PERCENTRANK)
MAP	MAP (English)	=MAP(A1:A2;LAMBDA(x;x*2))	spills 2 and 8
		=MAPUJ(…)	not a function: no autocomplete, #NAZWA?
BYCOL	BYCOL (English)	=BYCOL(A1:A2;LAMBDA(x;SUMA(x)))	5
		=KOLUMNAMI(…)	not a function: no autocomplete, #NAZWA?

So for these three the pl-pl pages disagree with what Excel for the web accepts, and the table follows Excel. Your point about desktop builds still stands: I can't check a desktop Excel 365 in Polish. If someone can, a desktop/web difference would be worth knowing. a71220c records the recheck in the header of input/pl.rs.

The table itself comes only from observing Excel with FORMULATEXT, as the header of pl.rs describes, not from the documentation. Whether that kind of observation is an acceptable source is still the open question for the maintainers in #430.

[brzuchal]

Closing in favour of #1678.

@quantmind-br thanks for the heads-up and for the offer. #443, which this was built on, is closed and split, and moving this branch onto #1522 would mean a rebase and force-push of a branch with an open PR, which I avoid. So I started clean: #1678 is cut from formula-dialects (73609ed) with the Polish interface from #650 merged in, and adds Polish in the same shape as your German branch: one input/pl.rs (the table from here, unchanged), one FormulaLocale variant, one arm in Language::formula_locale, and its tests.

The review here (@yrrh's comparison with the pl-pl pages and my recheck of ODSETEK, MAP and BYCOL in Excel) stays as the record behind the table; the header of pl.rs points to it.