Sheet names starting with '.' or reading as R1C1 (R, C, RC, R1C1...) were saved
unquoted, so Excel could not open the file; PivotTable sources and ADDRESS left
cell-like names (A1) bare. The quoting rule, unquoting and sheet splitting now
live once in gridcraft_core::addr and replace the copies in the formula printer,
pivot, ADDRESS, chart, xlsx, Solver, Go To and the Name Box (which now reads ''
as ').
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
A category range two or more columns wide beside a column of values (year beside month, Excel's
multiLvlStrRef) was read as one flat list: 36 rows in two columns became 72 categories, the
series sat in the left half of the plot and the years and months shared one row of labels.
Saving wrote the range as a plain strRef, so Excel lost the two-level axis too.
- gridcraft_core::category_levels: the shape of a category range beside its values (levels are
columns when the points run down the rows, rows when they run along the columns; up to three
outer levels), shared by the chart and xlsx crates.
- ChartData.category_levels: the outer levels, nearest the labels first, one entry per category,
non-empty where a group starts. resolve fills it; a single column is unchanged.
- render: the outer levels in rows under the labels, a group's name centred under its categories
with a separator at each boundary; in bar charts in columns beside the labels.
- xlsx: <c:cat> written as multiLvlStrRef with the level caches (innermost first), so the axis
survives a round trip.
Tests in core (shapes), chart (resolve and layout for columns, bars and a row of values) and
xlsx (written XML, read-back, stability, a single column stays strRef). chart-parity, gaps § 4
and the ROADMAP progress log updated.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
aiongg