Implement Wasm binding for Tree.getChangedRanges()

lib/binding_web/binding.js

@@ -175,6 +175,26 @@ class Tree {
   walk() {
     return this.rootNode.walk();
   }
+
+  getChangedRanges(other) {
+    if (other.constructor !== Tree) {
+      throw new TypeError('Argument must be a Tree');
+    }
+
+    C._ts_tree_get_changed_ranges_wasm(this[0], other[0]);
+    const count = getValue(TRANSFER_BUFFER, 'i32');
+    const buffer = getValue(TRANSFER_BUFFER + SIZE_OF_INT, 'i32');
+    const result = new Array(count);
+    if (count > 0) {
+      let address = buffer;
+      for (let i = 0; i < count; i++) {
+        result[i] = unmarshalRange(address);
+        address += SIZE_OF_RANGE;
+      }
+      C._free(buffer);
+    }
+    return result;
+  }
 }
 
 class Node {