fix: ListCompositeTreeViewDU to getAllReadonly() without commit (#456)

* fix: ListCompositeTreeViewDU to getAllReadonly() without commit()

* fix: lint

---------

Co-authored-by: Tuyen Nguyen <twoeths@users.noreply.github.com>

packages/ssz/src/viewDU/arrayComposite.ts

@@ -145,14 +145,16 @@ export class ArrayCompositeTreeViewDU<
   }
 
   /**
-   * WARNING: Returns all commited changes, if there are any pending changes commit them beforehand
+   * Returns all elements at every index, if an index is modified it will return the modified view.
+   * No need to commit() before calling this function.
    */
   getAllReadonly(): CompositeViewDU<ElementType>[] {
-    this.populateAllNodes();
+    this.populateAllOldNodes();
 
     const views = new Array<CompositeViewDU<ElementType>>(this._length);
     for (let i = 0; i < this._length; i++) {
-      views[i] = this.type.elementType.getViewDU(this.nodes[i], this.caches[i]);
+      // this will get pending change first, if not it will get from the `this.nodes` array
+      views[i] = this.getReadonly(i);
     }
     return views;
   }
@@ -256,4 +258,16 @@ export class ArrayCompositeTreeViewDU<
       this.nodesPopulated = true;
     }
   }
+
+  /**
+   * Similar to `populateAllNodes` but this does not require a commit() before reading all nodes.
+   * If there are pendingChanges, they will NOT be included in the `nodes` array.
+   */
+  protected populateAllOldNodes(): void {
+    if (!this.nodesPopulated) {
+      const originalLength = this.dirtyLength ? this.type.tree_getLength(this._rootNode) : this._length;
+      this.nodes = getNodesAtDepth(this._rootNode, this.type.depth, 0, originalLength);
+      this.nodesPopulated = true;
+    }
+  }
 }

packages/ssz/test/unit/byType/listComposite/tree.test.ts

@@ -120,7 +120,8 @@ describe("ListCompositeType tree reads", () => {
 
       // Only for viewDU
       if (view instanceof ArrayCompositeTreeViewDU) {
-        expect(() => view.getAllReadonly()).toThrow("Must commit changes before reading all nodes");
+        expect(() => view.getAllReadonly()).not.toThrow();
+        expect(() => view.getAllReadonlyValues()).toThrow("Must commit changes before reading all nodes");
         view.commit();
       }
 
@@ -337,3 +338,24 @@ describe("ListCompositeType batchHashTreeRoot", () => {
     });
   }
 });
+
+describe("ListCompositeType getAllReadOnly - no commit", () => {
+  it("getAllReadOnly() without commit", () => {
+    const listType = new ListCompositeType(ssz.Root, 1024);
+    const listLength = 2;
+    const list = Array.from({length: listLength}, (_, i) => Buffer.alloc(32, i));
+    const listView = listType.toViewDU(list);
+    expect(listView.getAllReadonly()).to.deep.equal(list);
+
+    // modify
+    listView.set(0, Buffer.alloc(32, 1));
+    // push
+    listView.push(Buffer.alloc(32, 1));
+
+    // getAllReadOnly() without commit, now all items should be the same
+    expect(listView.getAllReadonly()).to.deep.equal(Array.from({length: 3}, () => Buffer.alloc(32, 1)));
+
+    // getAllReadOnlyValues() will throw
+    expect(() => listView.getAllReadonlyValues()).toThrow("Must commit changes before reading all nodes");
+  });
+});