Merge pull request #33 from wingrunr21/tree_cursor_updates

Add reset and currentNode support to TreeCursor
tree-sitter · Nov 15, 2018 · 32df455 · 32df455
2 parents 81d5f45 + 2b16eb2
commit 32df455
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Showing 6 changed files with 37 additions and 2 deletions.
diff --git a/index.js b/index.js
@@ -339,9 +339,14 @@ Parser.prototype.parseTextBufferSync = function(buffer, oldTree, {includedRanges
   return tree;
 };
 
-const {startPosition, endPosition} = TreeCursor.prototype;
+const {startPosition, endPosition, currentNode, reset} = TreeCursor.prototype;
 
 Object.defineProperties(TreeCursor.prototype, {
+  currentNode: {
+    get() {
+      return currentNode.call(this) || unmarshalNode(this.tree);
+    }
+  },
   startPosition: {
     get() {
       startPosition.call(this);
@@ -361,6 +366,11 @@ Object.defineProperties(TreeCursor.prototype, {
   }
 });
 
+TreeCursor.prototype.reset = function(node) {
+  marshalNode(node);
+  reset.call(this);
+}
+
 function getTextFromString (node) {
   return this.input.substring(node.startIndex, node.endIndex);
 }

diff --git a/src/node.cc b/src/node.cc
@@ -85,7 +85,7 @@ void MarshalNullNode() {
   memset(transfer_buffer, 0, FIELD_COUNT_PER_NODE * sizeof(transfer_buffer[0]));
 }
 
-static TSNode UnmarshalNode(const Tree *tree) {
+TSNode UnmarshalNode(const Tree *tree) {
   TSNode result = {{0, 0, 0, 0}, nullptr, nullptr};
   result.tree = tree->tree_;
   if (!result.tree) {

diff --git a/src/node.h b/src/node.h
@@ -12,6 +12,7 @@ namespace node_methods {
 
 void Init(v8::Local<v8::Object>);
 void MarshalNode(const Nan::FunctionCallbackInfo<v8::Value> &info, const Tree *, TSNode);
+TSNode UnmarshalNode(const Tree *tree);
 
 static inline const void *UnmarshalNodeId(const uint32_t *buffer) {
   const void *result;

diff --git a/src/tree_cursor.cc b/src/tree_cursor.cc
@@ -4,6 +4,8 @@
 #include <v8.h>
 #include "./util.h"
 #include "./conversions.h"
+#include "./node.h"
+#include "./tree.h"
 
 namespace node_tree_sitter {
 
@@ -31,6 +33,8 @@ void TreeCursor::Init(v8::Local<v8::Object> exports) {
     {"gotoFirstChild", GotoFirstChild},
     {"gotoFirstChildForIndex", GotoFirstChildForIndex},
     {"gotoNextSibling", GotoNextSibling},
+    {"currentNode", CurrentNode},
+    {"reset", Reset},
   };
 
   for (size_t i = 0; i < length_of_array(getters); i++) {
@@ -112,6 +116,22 @@ void TreeCursor::EndPosition(const Nan::FunctionCallbackInfo<Value> &info) {
   TransferPoint(ts_node_end_point(node));
 }
 
+void TreeCursor::CurrentNode(const Nan::FunctionCallbackInfo<Value> &info) {
+  TreeCursor *cursor = Nan::ObjectWrap::Unwrap<TreeCursor>(info.This());
+  Local<String> key = Nan::New<String>("tree").ToLocalChecked();
+  const Tree *tree = Tree::UnwrapTree(info.This()->Get(key));
+  TSNode node = ts_tree_cursor_current_node(&cursor->cursor_);
+  node_methods::MarshalNode(info, tree, node);
+}
+
+void TreeCursor::Reset(const Nan::FunctionCallbackInfo<Value> &info) {
+  TreeCursor *cursor = Nan::ObjectWrap::Unwrap<TreeCursor>(info.This());
+  Local<String> key = Nan::New<String>("tree").ToLocalChecked();
+  const Tree *tree = Tree::UnwrapTree(info.This()->Get(key));
+  TSNode node = node_methods::UnmarshalNode(tree);
+  ts_tree_cursor_reset(&cursor->cursor_, node);
+}
+
 void TreeCursor::NodeType(v8::Local<v8::String> prop, const Nan::PropertyCallbackInfo<v8::Value> &info) {
   TreeCursor *cursor = Nan::ObjectWrap::Unwrap<TreeCursor>(info.This());
   TSNode node = ts_tree_cursor_current_node(&cursor->cursor_);

diff --git a/src/tree_cursor.h b/src/tree_cursor.h
@@ -24,6 +24,8 @@ class TreeCursor : public Nan::ObjectWrap {
   static void GotoNextSibling(const Nan::FunctionCallbackInfo<v8::Value> &);
   static void StartPosition(const Nan::FunctionCallbackInfo<v8::Value> &);
   static void EndPosition(const Nan::FunctionCallbackInfo<v8::Value> &);
+  static void CurrentNode(const Nan::FunctionCallbackInfo<v8::Value> &);
+  static void Reset(const Nan::FunctionCallbackInfo<v8::Value> &);
 
   static void NodeType(v8::Local<v8::String>, const Nan::PropertyCallbackInfo<v8::Value> &);
   static void NodeIsNamed(v8::Local<v8::String>, const Nan::PropertyCallbackInfo<v8::Value> &);

diff --git a/tree-sitter.d.ts b/tree-sitter.d.ts
@@ -92,7 +92,9 @@ declare module "tree-sitter" {
       endPosition: Point;
       startIndex: number;
       endIndex: number;
+      readonly currentNode: SyntaxNode
 
+      reset(node: SyntaxNode): void
       gotoParent(): boolean;
       gotoFirstChild(): boolean;
       gotoFirstChildForIndex(index: number): boolean;