fix: guard single-value continuous col width (#41)

Author: mcanouil

CHANGELOG.md

@@ -12,6 +12,7 @@
 - feat: `labs()` fields default to `auto`; pass `none` to suppress an axis or legend title and reclaim the space it reserved. (#12)
 - feat: `element-blank()` on a text surface (axis, plot, or legend title) collapses the space the text would reserve. (#12)
 - feat: `width`/`height` accept `auto` to fill the available space of a bounded container. (#10)
+- fix: `geom-col()` on a continuous x with a single distinct value no longer panics when inferring the bar width. (#41)
 - fix: `log10`/`sqrt` scales validate user `limits` and report a clear error for non-positive bounds. (#40)
 - fix: `geom-smooth()` honours the `level` argument when sizing the confidence band instead of always using 95%. (#39)
 - fix: binning geoms reject a non-positive `bins` with a clear error instead of dividing by zero. (#38)

src/geom/col.typ

@@ -295,10 +295,10 @@
       .map(r => parse-number(r.at(cat-col, default: none)))
       .filter(v => v != none)
     let (d-lo, d-hi) = cat-trained.domain
-    if xs.len() < 2 or d-hi == d-lo {
+    let sorted = xs.dedup().sorted()
+    if sorted.len() < 2 or d-hi == d-lo {
       (cat-hi - cat-lo) / 10
     } else {
-      let sorted = xs.dedup().sorted()
       let panel-gaps = range(sorted.len() - 1).map(i => calc.abs(
         map-axis(cat-trained, sorted.at(i + 1), cat-range)
           - map-axis(cat-trained, sorted.at(i), cat-range),