EPS: the useArtboards help text separates false from absent

useArtboards: false writes one file of the visible art even when artboards are named. With useArtboards absent, naming artboards writes the same files as useArtboards: true, including the no-art exception for the central file. The option description and the document.exportEps params text now say so, and the EPS test covers both cases.

crates/engine/src/cmd/fileio/eps.rs

@@ -29,7 +29,7 @@ pub fn specs() -> Vec<CommandSpec> {
         "Export EPS",
         [],
         None,
-        "{path?, level?: 2|3 (default; PostScript language level: 3 writes smooth gradients and masks transparent image pixels out, 2 steps gradients and writes those pixels white), previewFormat?: none|tiffBw|tiffColor (default: a TIFF preview other apps show), transparentPreview?: true (else on white), overprints?: preserve (default)|discard, flattenerPreset?: \"medium\" (default; high, low or a saved preset: flattener.presets.list), flattener?: {the options of object.flattenTransparency over the preset}, embedFonts?: true (type is always written as outlines, so no fonts are needed), includeLinkedFiles?: false (the embedded document keeps linked images whole, not just their previews), thumbnails?: true (a PNG thumbnail in the file), cmykPostScript?: true (RGB documents written in CMYK), compatibleGradients?: false (stepped gradients at level 3 too), selectedOnly?: false, useArtboards?: true (one file per chosen artboard, artboards?/range?, {stem}_{artboard}.eps, the bounding box the artboard; with two or more, also the central file {stem}.eps first: the whole document, the bounding box the visible art; none when no art shows) | false (default: one file, the bounding box the visible art, y up from the first artboard's bottom-left corner), format?: \"eps\", artboard?: i | artboards?: [i…] | range?: \"1-3, 5\" (with useArtboards: the artboards written)} → {path, bytes, warnings, files?}; no path → {dataBase64, …}. Transparency is flattened with the preset (EPS has none); the native document rides along in comments, for reopening the file as it was. Same as document.export {format: eps}",
+        "{path?, level?: 2|3 (default; PostScript language level: 3 writes smooth gradients and masks transparent image pixels out, 2 steps gradients and writes those pixels white), previewFormat?: none|tiffBw|tiffColor (default: a TIFF preview other apps show), transparentPreview?: true (else on white), overprints?: preserve (default)|discard, flattenerPreset?: \"medium\" (default; high, low or a saved preset: flattener.presets.list), flattener?: {the options of object.flattenTransparency over the preset}, embedFonts?: true (type is always written as outlines, so no fonts are needed), includeLinkedFiles?: false (the embedded document keeps linked images whole, not just their previews), thumbnails?: true (a PNG thumbnail in the file), cmykPostScript?: true (RGB documents written in CMYK), compatibleGradients?: false (stepped gradients at level 3 too), selectedOnly?: false, useArtboards?: true (one file per chosen artboard, artboards?/range?, {stem}_{artboard}.eps, the bounding box the artboard; with two or more, also the central file {stem}.eps first: the whole document, the bounding box the visible art; none when no art shows) | false (one file, the bounding box the visible art, y up from the first artboard's bottom-left corner, even when artboards are named; the default when none are named), format?: \"eps\", artboard?: i | artboards?: [i…] | range?: \"1-3, 5\" (the artboards written; naming them without useArtboards works as useArtboards: true)} → {path, bytes, warnings, files?}; no path → {dataBase64, …}. Transparency is flattened with the preset (EPS has none); the native document rides along in comments, for reopening the file as it was. Same as document.export {format: eps}",
         has_doc,
         export_eps
     )]
@@ -44,7 +44,7 @@ pub(super) const OPTIONS: &[FormatOption] = &[
         name: "useArtboards",
         ty: "boolean",
         default: "null",
-        description: "true: one file per chosen artboard (default all), <file>_<artboard>.eps, and with two or more a central <file>.eps of the whole document (none when no art shows); false or absent: one file of the visible art (naming artboards also uses them)",
+        description: "true: one file per chosen artboard (default all), <file>_<artboard>.eps, and with two or more a central <file>.eps of the whole document (none when no art shows); absent: the same when artboard, artboards or range names artboards, else one file of the visible art; false: one file of the visible art, even when artboards are named",
     },
     FormatOption { name: "level", ty: "integer", default: "3", description: "PostScript language level, 2 or 3" },
     FormatOption {

crates/engine/src/cmd/fileio/tests_eps.rs

@@ -102,6 +102,10 @@ fn use_artboards_writes_a_file_per_artboard_named_with_an_underscore() {
     let r = s.execute("document.exportEps", &json!({"range": "2", "previewFormat": "none"})).unwrap();
     assert!(r.get("files").is_none());
     assert!(postscript(&b64(&r)).contains(&format!("[1 0 0 -1 {} 100] cm", -second)));
+    // useArtboards: false writes one file of the visible art, even with artboards named.
+    let r = s.execute("document.exportEps", &json!({"useArtboards": false, "artboards": [0, 1], "previewFormat": "none"})).unwrap();
+    assert!(r.get("files").is_none());
+    assert_eq!(dsc(&postscript(&b64(&r)), "BoundingBox").as_deref(), Some(format!("10 60 {} 90", second + 40.0).as_str()));
     assert!(s.execute("document.exportEps", &json!({"artboard": 5})).is_err());
     // Without art there is nothing to bound.
     let mut empty = session(100.0, 100.0, 1);
@@ -110,6 +114,9 @@ fn use_artboards_writes_a_file_per_artboard_named_with_an_underscore() {
     let mut empty = session(100.0, 100.0, 2);
     let r = empty.execute("document.exportEps", &json!({"useArtboards": true, "previewFormat": "none"})).unwrap();
     assert_eq!(r["files"].as_array().map(Vec::len), Some(2), "{r}");
+    // Named artboards without useArtboards get the same files.
+    let r = empty.execute("document.exportEps", &json!({"range": "1-2", "previewFormat": "none"})).unwrap();
+    assert_eq!(r["files"].as_array().map(Vec::len), Some(2), "{r}");
 }
 
 #[test]