plugin-report README's export snippets call every real export with the wrong signature — exportAsCSV(data, 'file.csv') passes a filename where the data argument goes #5048

Found while implementing #5016 (three fabricated exports in packages/plugin-report/README.md). Filed unassigned, out of that card's scope, and it is a different defect class: #5016's three names are not on the export surface at all, while every name below IS real — what is wrong is the arity and argument order of the call. The name-set check that #5016 uses cannot see this class, because each of these imports reads as REAL.

Measured on origin/main at dc9d651a2c55c10a9e4d30434e429e5fdc5ae968. Line numbers are as they will be after the PR for #5016 (they shift, the blocks do not).

The three blocks

1. README.md:229-241 — the six format exporters. Real signature (src/ReportExportEngine.ts:19,43,57,96,151):

export function exportAsCSV(report: ReportComponentSchema, data: any[], config?: ReportExportConfig): void

The README calls them as (data, filename):

await exportAsCSV(reportData, 'sales-report.csv');
await exportAsPDF(reportData, 'sales-report.pdf');
await exportAsExcel(reportData, 'sales-report.xlsx');

So reportData lands in the report parameter (the schema, which is where headers, fields and title are read from) and the filename string lands in data, which the engine iterates as rows. Two further mismatches in the same three lines: there is no filename parameter at all — the name comes from report.title / config — and all five are void, not async, so the await is inert. exportReport(format, report, data, config) at :175 takes the format FIRST, which the import list implies but no snippet shows.

2. README.md:245-253 — exportWithLiveData. Real signature (src/LiveReportExporter.ts:97) takes LiveExportOptions, in which dataSource and resource are required (:34-45):

await exportWithLiveData(reportConfig, { format: 'pdf' });   // README

Missing both required keys, so this is a compile error, not a silent misfire. The function's own doc example at :88-95 shows the correct shape.

3. README.md:249-252 — exportExcelWithFormulas. Real signature (src/LiveReportExporter.ts:161) is (report, data, options) — three parameters, with the column list inside the third. The README passes two, and spells the column key field:

await exportExcelWithFormulas(reportConfig, {
  columns: [{ field: 'total', formula: 'SUM(B2:B100)' }],
});

ExcelColumnConfig (:50-61) has no field — it is { name, header, width?, numberFormat?, formula? }, and name is what the exporter reads (row[col.name]). The formula template also uses a {ROW} placeholder the snippet's SUM(B2:B100) does not exercise; the real doc example at :139-146 shows '=B{ROW}*C{ROW}'.

Impact

Block 2 fails to compile, so a reader is stopped. Blocks 1 and 3 are worse: they type-check as written against any[]/loose params and fail at runtime or, in block 1's case, quietly export a spreadsheet built from the characters of a filename. Nothing gates a package README's API assertions today (#5016's grading note).

Recheck

grep -n "export function exportAs\|export function exportReport" packages/plugin-report/src/ReportExportEngine.ts
grep -n "export async function exportWithLiveData" -A 4 packages/plugin-report/src/LiveReportExporter.ts
grep -n "export function exportExcelWithFormulas" -A 8 packages/plugin-report/src/LiveReportExporter.ts
grep -n "interface ExcelColumnConfig" -A 12 packages/plugin-report/src/LiveReportExporter.ts

Suggested fix: rewrite the three blocks against the signatures, reusing the JSDoc examples already in LiveReportExporter.ts (they are correct). Worth pricing at the same time: whether a docs gate could type-check fenced ts/tsx blocks in package READMEs — scripts/extract-mdx-demos.mjs already does something adjacent for the docs site, and this whole family (#5002, #5010-#5016, this card) exists because nothing checks them.

Related: #5016 (the fabricated-name half of the same file, in flight), #5047 (the retired query form the same file teaches), #5002 / PR #5021 (precedent).