#1063: a fill chosen with characters selected colours just them

Choosing a fill or stroke (Color panel, Swatches, the proxies) while the
Type tool had a few characters selected painted every run of the type
object. As in Illustrator, it now goes to the selected characters only:
the runs are split at the selection's ends and the paint is placed on
the runs in between, as one undo step; a stroke gets a 1 pt weight
where it had none. With only a caret, or with explicit ids or an item,
paint.setFill/setStroke behave as before.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/engine/src/cmd/paint.rs

@@ -16,7 +16,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Fill",
             [],
             None,
-            "{color?: \"#rrggbb\"|[r,g,b]|{c,m,y,k}|{gray}|{l,a,b} (CIE Lab), none?: true, swatch?: name (a global or spot colour stays linked, so swatch edits recolour it; a tint swatch links to its base at its tint; a gradient swatch is recorded as the gradient's swatch and fits each object, keeping its aspect; the built-in \"[Registration]\" prints on every plate), tint?: 0..100 (% of a global or spot `swatch`; default 100, or a tint swatch's own), gradient?: {kind?: linear|radial|freeform, stops?: [{offset 0..1, color, opacity? 0..1 (or 0..100), midpoint? 0.13..0.87, swatch?: global or spot colour (or tint) swatch the stop links to (its colour comes from the swatch), tint?: 0..100}] (at least 2; default white→black), angle?: deg, start?: [x,y], end?: [x,y] (the vector in document coordinates, both or neither; type objects keep it in text space), aspect?: % (radial; without start/end the gradient is placed on each object's bounds), focal?: [x,y] (radial, with start/end: the focal point, where the first stop sits), swatch?: linked gradient swatch name}, item?: appearance item index|null (omitted: the Appearance panel's active item if it is a fill, else the top fill), ids?, focus?: true (false keeps the active proxy), keepModel?: false (in a CMYK document, RGB colours and gradient stops are stored as CMYK unless true; Gray stays Gray)} sets the selection's fill and the default (new art fits a gradient to itself)",
+            "{color?: \"#rrggbb\"|[r,g,b]|{c,m,y,k}|{gray}|{l,a,b} (CIE Lab), none?: true, swatch?: name (a global or spot colour stays linked, so swatch edits recolour it; a tint swatch links to its base at its tint; a gradient swatch is recorded as the gradient's swatch and fits each object, keeping its aspect; the built-in \"[Registration]\" prints on every plate), tint?: 0..100 (% of a global or spot `swatch`; default 100, or a tint swatch's own), gradient?: {kind?: linear|radial|freeform, stops?: [{offset 0..1, color, opacity? 0..1 (or 0..100), midpoint? 0.13..0.87, swatch?: global or spot colour (or tint) swatch the stop links to (its colour comes from the swatch), tint?: 0..100}] (at least 2; default white→black), angle?: deg, start?: [x,y], end?: [x,y] (the vector in document coordinates, both or neither; type objects keep it in text space), aspect?: % (radial; without start/end the gradient is placed on each object's bounds), focal?: [x,y] (radial, with start/end: the focal point, where the first stop sits), swatch?: linked gradient swatch name}, item?: appearance item index|null (omitted: the Appearance panel's active item if it is a fill, else the top fill), ids?, focus?: true (false keeps the active proxy), keepModel?: false (in a CMYK document, RGB colours and gradient stops are stored as CMYK unless true; Gray stays Gray)} sets the selection's fill and the default (new art fits a gradient to itself); while the Type tool has characters selected (and no ids or item are given), the paint goes to those characters only",
             has_doc,
             |s, p| set_paint(s, p, true)
         ),
@@ -375,6 +375,34 @@ fn apply_to_proxy(s: &mut Session, p: &Value, paint: Paint) -> Result<Value> {
 /// remember the paint.
 fn apply_paint(s: &mut Session, p: &Value, paint: Paint, fill: bool) -> Result<Value> {
     let cmd = if fill { "paint.setFill" } else { "paint.setStroke" };
+    // Characters selected with the Type tool take the paint, not the whole type object (#1063).
+    if p.get("ids").is_none()
+        && p.get("item").is_none()
+        && let Some((id, a, b)) = super::textedit::editing_range(s)?
+        && a != b
+    {
+        s.edit(if fill { "Fill Color" } else { "Stroke Color" }, |d, _| {
+            let Some(NodeKind::Text(t)) = d.node_mut(id).map(|n| &mut n.kind) else { return Err(EngineError::NoNode(id)) };
+            let (xf, lb) = (t.xf, t.local_bounds());
+            vectorcraft_text::edit::style_range(&mut t.runs, a, b, |st| {
+                if fill {
+                    st.fill = place_run_paint(&paint, p, xf, lb);
+                } else {
+                    if !paint.is_none() {
+                        run_stroke_weight(st);
+                    }
+                    st.stroke = place_run_paint(&paint, p, xf, vectorcraft_doc::appearance::stroke_paint_bounds(lb, st.stroke_width));
+                }
+            });
+            super::typecmd::refresh_bounds(t);
+            Ok(())
+        })?;
+        if bool_or(p, "focus", true) {
+            s.fill_active = fill;
+        }
+        s.remember_paint(&paint);
+        return ok();
+    }
     // Resolve the requested targets before mutating defaults or the active proxy.
     let item = item_target(s, p, cmd)?.of_kind(s, fill);
     let selected = item.targets(s, p)?;

crates/engine/src/cmd/textedit.rs

@@ -542,7 +542,7 @@ enum Step {
 }
 
 /// The Type tool's selected text while it edits (its typing session ends first: one undo step).
-fn editing_range(s: &mut Session) -> Result<Option<(NodeId, usize, usize)>> {
+pub(crate) fn editing_range(s: &mut Session) -> Result<Option<(NodeId, usize, usize)>> {
     let o = s.tool_options();
     let Some(id) = o.get("editing").and_then(Value::as_u64).map(NodeId) else { return Ok(None) };
     if super::edit::typing_in_progress(s) {

crates/engine/src/tests_textedit.rs

@@ -563,3 +563,35 @@ fn automatic_alignment_updates_during_edits_and_can_be_overridden() {
     legacy["para"]["justify"] = json!("Left");
     assert_eq!(serde_json::from_value::<TextObject>(legacy).unwrap().para.justify, vectorcraft_doc::Justify::Left);
 }
+
+/// #1063: a fill (or stroke) chosen while the Type tool has characters selected colours just
+/// those characters, as one undo step; the rest of the type keeps its colour.
+#[test]
+fn a_fill_chosen_with_characters_selected_colours_only_them() {
+    let mut s = session();
+    let v = ViewInfo::default();
+    s.select_tool("type", v).unwrap();
+    click(&mut s, 50.0, 300.0);
+    let id = s.doc().unwrap().selection.objects[0];
+    s.tool_text("Sample Text", v).unwrap();
+    let before = obj(&s, id).runs[0].style.fill.clone();
+    s.set_tool_option("select", &json!({"start": 0, "end": 6}));
+    s.execute("paint.setFill", &json!({"color": "#00a000"})).unwrap();
+    let t = obj(&s, id);
+    assert_eq!(t.runs.len(), 2);
+    assert_eq!(t.runs[0].text, "Sample");
+    assert_eq!(t.runs[0].style.fill, Paint::solid(vectorcraft_color::Color::rgb8(0, 160, 0)));
+    assert_eq!(t.runs[1].text, " Text");
+    assert_eq!(t.runs[1].style.fill, before);
+    // A stroke goes on the selected characters only, with a weight to show.
+    s.execute("paint.setStroke", &json!({"color": "#ff0000"})).unwrap();
+    let t = obj(&s, id);
+    assert!(t.runs[0].style.stroke_width > 0.0 && !t.runs[0].style.stroke.is_none());
+    assert!(t.runs[1].style.stroke.is_none());
+    // One undo step each.
+    let labels = undo_labels(&s);
+    assert_eq!(&labels[labels.len() - 2..], ["Fill Color", "Stroke Color"]);
+    s.execute("edit.undo", &json!({})).unwrap();
+    s.execute("edit.undo", &json!({})).unwrap();
+    assert!(obj(&s, id).runs.iter().all(|r| r.style.fill == before));
+}