Add tests for previous sibling, last child

lib/binding_web/exports.json

@@ -105,7 +105,7 @@
   "_ts_tree_cursor_end_index_wasm",
   "_ts_tree_cursor_end_position_wasm",
   "_ts_tree_cursor_goto_first_child_wasm",
-  "_ts_tree_cursor_goto_last_child",
+  "_ts_tree_cursor_goto_last_child_wasm",
   "_ts_tree_cursor_goto_next_sibling_wasm",
   "_ts_tree_cursor_goto_previous_sibling_wasm",
   "_ts_tree_cursor_goto_parent_wasm",

lib/binding_web/test/tree-test.js

@@ -244,6 +244,50 @@ describe("Tree", () => {
         endIndex: 13
       });
 
+      {
+        const copy = tree.walk();
+        copy.resetTo(cursor);
+
+        assert(copy.gotoPreviousSibling());
+        assertCursorState(copy, {
+          nodeType: '+',
+          nodeIsNamed: false,
+          startPosition: {row: 0, column: 6},
+          endPosition: {row: 0, column: 7},
+          startIndex: 6,
+          endIndex: 7
+        });
+
+        assert(copy.gotoPreviousSibling());
+        assertCursorState(copy, {
+          nodeType: 'binary_expression',
+          nodeIsNamed: true,
+          startPosition: {row: 0, column: 0},
+          endPosition: {row: 0, column: 5},
+          startIndex: 0,
+          endIndex: 5
+        });
+
+        assert(copy.gotoLastChild());
+        assertCursorState(copy, {
+          nodeType: "identifier",
+          nodeIsNamed: true,
+          startPosition: {row: 0, column: 4},
+          endPosition: {row: 0, column: 5},
+          startIndex: 4,
+          endIndex: 5
+        })
+
+        assert(copy.gotoParent());
+        assert(copy.gotoParent());
+        assert.equal(copy.nodeType, 'binary_expression')
+        assert(copy.gotoParent());
+        assert.equal(copy.nodeType, 'expression_statement')
+        assert(copy.gotoParent());
+        assert.equal(copy.nodeType, 'program')
+        assert(!copy.gotoParent());
+    }
+
       // const childIndex = cursor.gotoFirstChildForIndex(12);
       // assertCursorState(cursor, {
       //   nodeType: 'identifier',