PPTX: table styles the file defines are kept on save even when no table uses them

crates/pptx/src/tables.rs

@@ -229,6 +229,16 @@ pub fn table_styles_xml(used: &[String], defs: &[deckcraft_model::table::TableSt
         let name = names.iter().find(|(id, _)| id == s).map(|(_, n)| format!("DeckCraft {n}")).unwrap_or_else(|| s.clone());
         style_def(&mut w, s, &name);
     }
+    // Styles the file defined but no table uses still belong to the deck.
+    for d in defs {
+        if done.iter().any(|s| s.eq_ignore_ascii_case(&d.id)) {
+            continue;
+        }
+        if crate::xml::parse(d.raw.as_bytes()).is_ok_and(|x| x.root.is("tblStyle")) {
+            done.push(&d.id);
+            w.raw(&d.raw);
+        }
+    }
     w.close("a:tblStyleLst");
     w.finish()
 }

crates/pptx/tests/table_styles.rs

@@ -82,3 +82,16 @@ fn table_styles_the_file_defines_are_read_used_and_kept() {
     let def2 = q.table_styles.iter().find(|d| d.id == STYLE_GUID).expect("kept on save");
     assert_eq!(def2.parts, def.parts);
 }
+
+#[test]
+fn table_style_no_table_uses_is_kept_on_save() {
+    let mut p = deckcraft_pptx::import(&table_deck()).expect("import");
+    assert!(p.table_styles.iter().any(|d| d.id == STYLE_GUID));
+    // Drop the only table that uses the style; the deck still defines it.
+    for s in &mut p.slides {
+        std::sync::Arc::make_mut(s).shapes.retain(|sh| !matches!(sh.kind, deckcraft_model::ShapeKind::Table(_)));
+    }
+    let q = deckcraft_pptx::import(&deckcraft_pptx::export(&p).expect("export")).expect("reimport");
+    let d = q.table_styles.iter().find(|d| d.id == STYLE_GUID).expect("style kept");
+    assert_eq!(d.name, "Probe Style");
+}