Add shared IDML cross-reference source writer

crates/idml/src/model/mod.rs

@@ -45,7 +45,7 @@ pub use spread::{
     TextWrapPreference, spreads,
 };
 pub use story::{
-    Ace, AnchoredObjectSetting, AnchoredObjectValues, CONTAINERS, Cell, CellOptions, Container, ContainerKind, ContentPart,
+    Ace, AnchoredObjectSetting, AnchoredObjectValues, CONTAINERS, Cell, CellOptions, Container, ContainerKind, ContentPart, CrossReferenceSource,
     IndexCrossReferenceValues, IndexDocument, IndexReference, IndexTopicPath, IndexValues, PageReference, Range, SavedCrossReference,
     SavedCrossReferencePart, Story, StoryAnchor, StoryPreference, Table, TableChild, TableColumn, TableLayout, TableRow, TextNode, TrackedChangeKind,
     stories,

crates/idml/src/model/story.rs

@@ -337,6 +337,20 @@ pub struct SavedCrossReference {
     pub character_range: Option<Range>,
 }
 
+/// The IDML cross-reference source wrapper around its saved character range.
+pub struct CrossReferenceSource;
+
+impl CrossReferenceSource {
+    pub fn to_el(self_id: &str, applied_format: &str, name: &str, character_range: El) -> El {
+        El::new("CrossReferenceSource")
+            .with_attr("Self", self_id)
+            .with_attr("AppliedFormat", applied_format)
+            .with_attr("Name", name)
+            .with_attr("Hidden", "false")
+            .with_child(character_range)
+    }
+}
+
 #[derive(Clone, Debug, PartialEq)]
 pub enum SavedCrossReferencePart {
     Text(String),