clean up js errors

automerge-backend-wasm/index.js

@@ -77,13 +77,8 @@ function getRedoStack(backend) {
   return backendState(backend).getRedoStack()
 }
 
-function decodeChange(backend,change) {
-  return backendState(backend).decodeChange(change)
-}
-
 module.exports = {
   initCodecFunctions,
   init, clone, free, applyChanges, applyLocalChange, loadChanges, getPatch,
   getChanges, getChangesForActor, getMissingDeps, getUndoStack, getRedoStack,
-  decodeChange
 }

automerge-backend-wasm/src/lib.rs

@@ -142,9 +142,9 @@ impl State {
 }
 
 fn automerge_error_to_js(err: AutomergeError) -> JsValue {
-    JsValue::from(std::format!("Automerge error: {}", err))
+    js_sys::Error::new(&std::format!("Automerge error: {}", err)).into()
 }
 
 fn json_error_to_js(err: serde_json::Error) -> JsValue {
-    JsValue::from(std::format!("serde_json error: {}", err))
+    js_sys::Error::new(&std::format!("serde_json error: {}", err)).into()
 }

automerge-backend/src/columnar.rs

@@ -316,12 +316,12 @@ impl<'a> Columns<'a> {
     }
 
     // FIXME - this could be an iterator (zip).map()
-    fn child(&mut self) -> Option<ObjectID> {
+    fn child(&mut self) -> Option<Option<ObjectID>> {
         let actor = self.chld_actor.next()?;
         let ctr = self.chld_ctr.next()?;
         match (actor, ctr) {
-            (None, None) => Some(ObjectID::Root),
-            (Some(a), Some(c)) => Some(self.op_id(a, c)?.to_object_id()),
+            (None, None) => Some(None),
+            (Some(a), Some(c)) => Some(Some(self.op_id(a, c)?.to_object_id())),
             _ => None,
         }
     }
@@ -465,7 +465,7 @@ impl<'a> Columns<'a> {
                     return None;
                 }
             }
-            Action::Link => OpType::Link(child),
+            Action::Link => OpType::Link(child?),
         };
         Some(Operation {
             action,

automerge-backend/src/encoding.rs

@@ -12,7 +12,7 @@ fn err(s: &str) -> AutomergeError {
 #[derive(Clone)]
 pub(crate) struct Decoder<'a> {
     pub offset: usize,
-    pub buf: &'a [u8],
+    buf: &'a [u8],
 }
 
 impl<'a> Decoder<'a> {