fix: improve type declarations

Author: ObserverOfTime

index.js

@@ -18,10 +18,10 @@ Object.defineProperty(Tree.prototype, 'rootNode', {
       Due to a race condition arising from Jest's worker pool, "this"
       has no knowledge of the native extension if the extension has not
       yet loaded when multiple Jest tests are being run simultaneously.
-      If the extension has correctly loaded, "this" should be an instance 
+      If the extension has correctly loaded, "this" should be an instance
       of the class whose prototype we are acting on (in this case, Tree).
-      Furthermore, the race condition sometimes results in the function in 
-      question being undefined even when the context is correct, so we also 
+      Furthermore, the race condition sometimes results in the function in
+      question being undefined even when the context is correct, so we also
       perform a null function check.
     */
     if (this instanceof Tree && rootNode) {
@@ -61,7 +61,10 @@ Tree.prototype.walk = function() {
 
 class SyntaxNode {
   constructor(tree) {
-    this.tree = tree;
+    Object.defineProperty(this, 'tree', {
+      value: tree,
+      enumerable: true
+    });
   }
 
   [util.inspect.custom]() {
@@ -903,8 +906,16 @@ function initializeLanguageNodeClasses(language) {
 
     const className = camelCase(typeName, true) + 'Node';
     const nodeSubclass = eval(`class ${className} extends SyntaxNode {${classBody}}; ${className}`);
-    nodeSubclass.prototype.type = typeName;
-    nodeSubclass.prototype.fields = Object.freeze(fieldNames.sort())
+    Object.defineProperties(nodeSubclass.prototype, {
+      type: {
+        value: typeName,
+        enumerable: true
+      },
+      fields: {
+        value: Object.freeze(fieldNames.sort()),
+        enumerable: true
+      }
+    });
     nodeSubclasses[id] = nodeSubclass;
   }
 

test/lookahead_iterable_test.js

@@ -1,4 +1,5 @@
-/** @type {typeof import('tree-sitter')} */
+/// <reference path="../tree-sitter.d.ts" />
+/** @type {typeof import("tree-sitter")} */
 const Parser = require("../index.js");
 const Rust = require("tree-sitter-rust");
 const assert = require('node:assert');

test/node_test.js

@@ -1,5 +1,6 @@
-/** @type {typeof import('tree-sitter')} */
-const Parser = require("../index.js");
+/// <reference path="../tree-sitter.d.ts" />
+/** @type {typeof import("tree-sitter")} */
+const Parser = require("../index");
 
 const C = require('tree-sitter-c');
 const EmbeddedTemplate = require('tree-sitter-embedded-template');
@@ -64,17 +65,15 @@ describe("Node", () => {
       `);
 
       const classNode = tree.rootNode.firstChild;
-      // @ts-ignore
       assert.deepEqual(classNode.fields, ['bodyNode', 'decoratorNodes', 'nameNode'])
 
-      // @ts-ignore
       const methodNode = classNode.bodyNode.firstNamedChild;
       assert.equal(methodNode.constructor.name, 'MethodDefinitionNode');
       assert.equal(methodNode.nameNode.text, 'b');
       assert.deepEqual(methodNode.fields, ['bodyNode', 'decoratorNodes', 'nameNode', 'parametersNode'])
 
       const decoratorNodes = methodNode.decoratorNodes;
-      assert.deepEqual(decoratorNodes.map(_ => _.text), ['@autobind', '@something'])
+      assert.deepEqual(decoratorNodes.map(n => n.text), ['@autobind', '@something'])
 
       const paramsNode = methodNode.parametersNode;
       assert.equal(paramsNode.constructor.name, 'FormalParametersNode');
@@ -707,14 +706,14 @@ describe("Node", () => {
 
   describe(".text", () => {
     Object.entries({
-      '.parse(String)': (parser, src) => parser.parse(src),
-      '.parse(Function)': (parser, src) =>
-        parser.parse(offset => src.substr(offset, 4)),
+      '.parse(String)': (/** @type {import('tree-sitter')} */ parser, /** @type {string} */ src) => parser.parse(src),
+      '.parse(Function)': (/** @type {import('tree-sitter')} */ parser, /** @type {string} */ src) =>
+        parser.parse(offset => src.substring(offset, offset + 4)),
     }).forEach(([method, parse]) =>
       it(`returns the text of a node generated by ${method}`, async () => {
         const src = "α0 / b👎c👎"
         const [numeratorSrc, denominatorSrc] = src.split(/\s*\/\s+/)
-        const tree = await parse(parser, src)
+        const tree = parse(parser, src)
         const quotientNode = tree.rootNode.firstChild.firstChild;
         const [numerator, slash, denominator] = quotientNode.children;
 
@@ -921,10 +920,8 @@ describe("Node", () => {
     it("shouldn't segfault when accessing properties on the prototype", () => {
       const tree = parser.parse('2 + 2');
       const nodePrototype = Object.getPrototypeOf(tree.rootNode);
-      // const nodePrototype = tree.rootNode.__proto__;
 
       const properties = [
-        "type",
         "typeId",
         "isNamed",
         "isMissing",
@@ -950,6 +947,9 @@ describe("Node", () => {
         "previousSibling",
         "previousNamedSibling",
       ];
+      if (nodePrototype.constructor.name === "SyntaxNode") {
+        assert.throws(() => { nodePrototype.type; }, TypeError)
+      }
       for (const property of properties) {
         assert.throws(() => { nodePrototype[property]; }, TypeError)
       }

test/parser_test.js

@@ -1,4 +1,5 @@
-/** @type {typeof import('tree-sitter')} */
+/// <reference path="../tree-sitter.d.ts" />
+/** @type {typeof import("tree-sitter")} */
 const Parser = require("../index.js");
 const HTML = require('tree-sitter-html');
 const JavaScript = require('tree-sitter-javascript');
@@ -17,6 +18,7 @@ describe("Parser", () => {
 
   describe(".setLanguage", () => {
     it("throws an exception when the supplied object is not a tree-sitter language", () => {
+      // @ts-expect-error: Invalid language
       assert.throws(() => parser.setLanguage({}), /Invalid language/);
       assert.throws(() => parser.setLanguage(undefined), /Invalid language/);
     });
@@ -166,7 +168,7 @@ describe("Parser", () => {
 
     describe("when the input callback returns something other than a string", () => {
       it("stops reading", () => {
-        const parts = ["abc", "def", "ghi", {}, {}, {}, "second-word", " "];
+        const parts = ["abc", "def", "ghi", null, null, null, "second-word", " "];
         const tree = parser.parse(() => parts.shift());
         assert.equal(
           tree.rootNode.toString(),

test/query_test.js

@@ -1,4 +1,5 @@
-/** @type {typeof import('tree-sitter')} */
+/// <reference path="../tree-sitter.d.ts" />
+/** @type {typeof import("tree-sitter")} */
 const Parser = require("../index.js");
 
 const C = require("tree-sitter-c");

test/tree_test.js

@@ -1,4 +1,5 @@
-/** @type {typeof import('tree-sitter')} */
+/// <reference path="../tree-sitter.d.ts" />
+/** @type {typeof import("tree-sitter")} */
 const Parser = require("../index.js");
 const JavaScript = require('tree-sitter-javascript');
 const Rust = require('tree-sitter-rust');