Merge #456: Wrap saved story revision counters consistently

Conflict: crates/doc/src/edit.rs: next's thread_frames (append_story); every rev += 1 is rev.wrapping_add(1)
Conflict: crates/engine/src/cmd/fonts.rs: next's replace (the local-formatting pass moved out of this hunk)
Conflict: crates/engine/src/cmd/text.rs: next's format_chars (apply_char_attrs, typing format); rev += 1 is rev.wrapping_add(1)

crates/engine/src/cmd/anchored.rs

@@ -190,7 +190,7 @@ fn options(s: &mut Session, p: &Value) -> Result<Value> {
         let st = d.story_mut(sid).ok_or(designcraft_doc::DocError::NoStory(sid))?;
         let o = st.objects.get_mut(k).ok_or_else(|| bad("anchored.options", "no such anchored object"))?;
         Arc::make_mut(o).position = position.clone();
-        st.rev += 1;
+        st.rev = st.rev.wrapping_add(1);
         Ok(json!({"position": position}))
     })
 }

crates/engine/src/cmd/editorial.rs

@@ -47,7 +47,7 @@ pub fn specs() -> Vec<CommandSpec> {
                 if let Some(a) = author {
                     n.author = a;
                 }
-                st.rev += 1;
+                st.rev = st.rev.wrapping_add(1);
                 ok()
             })
         }),

crates/engine/src/cmd/linked.rs

@@ -12,7 +12,7 @@ fn copy_into(d: &mut Document, parent: StoryId, child: StoryId) -> Result<()> {
     let src = d.story(parent).ok_or_else(|| bad("story.link", format!("no story {}", parent.0)))?.clone();
     let st = d.story_mut(child).ok_or_else(|| bad("story.link", format!("no story {}", child.0)))?;
     let (frames, rev) = (std::mem::take(&mut st.frames), st.rev);
-    *st = Story { id: child, frames, rev: rev + 1, link: Some((parent, src.rev)), ..src };
+    *st = Story { id: child, frames, rev: rev.wrapping_add(1), link: Some((parent, src.rev)), ..src };
     Ok(())
 }
 
@@ -94,6 +94,26 @@ mod tests {
 
     use crate::Session;
 
+    #[test]
+    fn linked_story_update_wraps_the_child_revision() {
+        let mut s = Session::new();
+        s.execute("file.new", &json!({})).unwrap();
+        let p = s.execute("frame.create", &json!({"rect": [0, 0, 100, 100], "content": "text", "text": "Original"})).unwrap();
+        let c = s.execute("story.placeAndLink", &json!({"story": p["story"], "rect": [100, 0, 200, 100]})).unwrap();
+        let child = designcraft_doc::StoryId(c["story"].as_u64().unwrap());
+        std::sync::Arc::make_mut(&mut s.doc_mut().unwrap().doc).story_mut(child).unwrap().rev = u64::MAX;
+        s.execute("story.setText", &json!({"story": p["story"], "text": "Revised"})).unwrap();
+        s.execute("story.updateLink", &json!({"story": c["story"]})).unwrap();
+        let st = s.doc().unwrap().doc.story(child).unwrap();
+        assert_eq!(st.text, "Revised");
+        assert_eq!(st.rev, 0);
+        assert_eq!(s.execute("story.links", &json!({})).unwrap()[0]["outOfDate"], false);
+        s.execute("edit.undo", &json!({})).unwrap();
+        assert_eq!(s.doc().unwrap().doc.story(child).unwrap().text, "Original");
+        s.execute("edit.redo", &json!({})).unwrap();
+        assert_eq!(s.doc().unwrap().doc.story(child).unwrap().text, "Revised");
+    }
+
     #[test]
     fn linked_story_goes_out_of_date_and_updates() {
         let mut s = Session::new();

crates/engine/src/cmd/style.rs

@@ -623,7 +623,7 @@ fn rename_style(d: &mut designcraft_doc::Document, para: bool, from: &str, to: &
                     rename_char_refs(&mut f.para, from, to);
                 }
             }
-            st.rev += 1;
+            st.rev = st.rev.wrapping_add(1);
         });
     }
 }

crates/engine/src/cmd/table.rs

@@ -1363,7 +1363,7 @@ fn reapply_cell_styles(d: &mut Document, names: &[String]) {
                 }
             }
         }
-        st.rev += 1;
+        st.rev = st.rev.wrapping_add(1);
     }
 }
 
@@ -1488,7 +1488,7 @@ fn table_style_edit(s: &mut Session, p: &Value) -> Result<Value> {
                     ts.apply_to(std::sync::Arc::make_mut(t), &cells);
                 }
             }
-            st.rev += 1;
+            st.rev = st.rev.wrapping_add(1);
         }
         ok()
     })

crates/engine/src/cmd/text.rs

@@ -801,7 +801,7 @@ pub(crate) fn set_story_direction(d: &mut designcraft_doc::Document, stories: &[
             && st.vertical != vertical
         {
             st.vertical = vertical;
-            st.rev += 1;
+            st.rev = st.rev.wrapping_add(1);
         }
     }
 }
@@ -1329,7 +1329,7 @@ pub(crate) fn apply_char_attrs(d: &mut designcraft_doc::Document, targets: &[Tar
                 && let Some(run) = st.chars.first_mut()
             {
                 run.format.over.merge(a);
-                st.rev += 1;
+                st.rev = st.rev.wrapping_add(1);
             }
             continue;
         }

crates/engine/src/cmd/xml.rs

@@ -438,7 +438,7 @@ fn import_xml(s: &mut Session, p: &Value) -> Result<Value> {
                 }
             }
             fresh.frames = frames;
-            fresh.rev = st.rev + 1;
+            fresh.rev = st.rev.wrapping_add(1);
             *st = fresh;
         }
         Ok(json!({"placed": placed, "unmatched": unmatched}))

crates/engine/src/cmd/xref.rs

@@ -162,7 +162,7 @@ fn set_format(s: &mut Session, p: &Value) -> Result<Value> {
         let st = d.story_mut(sid).ok_or(designcraft_doc::DocError::NoStory(sid))?;
         let x = st.xrefs.get_mut(k).ok_or_else(|| bad("xref.setFormat", "no such cross-reference"))?;
         std::sync::Arc::make_mut(x).format = format;
-        st.rev += 1;
+        st.rev = st.rev.wrapping_add(1);
         Ok(Value::Null)
     })
 }