From 53d272e8138f5f6353b98535a2bf1c78be6da735 Mon Sep 17 00:00:00 2001
From: Albert Xing <albert@makenotion.com>
Date: Thu, 9 Oct 2025 16:37:17 -0700
Subject: [PATCH] docs: more types for promise wrapper

---
 index.d.ts |  2 +-
 promise.js | 23 ++++++++++++++++++++++-
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 2384f77..15b33b4 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -153,7 +153,7 @@ export declare class Statement {
    *
    * * `params` - The parameters to bind to the statement.
    */
-  run(params?: unknown | undefined | null): object
+  run(params?: unknown | undefined | null): RunResult
   /**
    * Executes a SQL statement and returns the first row.
    *
diff --git a/promise.js b/promise.js
index 378e8fe..1c9e673 100644
--- a/promise.js
+++ b/promise.js
@@ -8,6 +8,15 @@ const Authorization = require("./auth");
  * @import {Options as NativeOptions, Statement as NativeStatement} from './index.js'
  */
 
+/**
+ * better-sqlite3-compatible types for db.transaction()
+ * @typedef {(...params: any[]) => unknown} VariableArgFunction
+ */
+/**
+ * @template {VariableArgFunction} F
+ * @typedef {F extends (...args: infer A) => unknown ? A : never} ArgumentTypes
+ */
+
 function convertError(err) {
   // Handle errors from Rust with JSON-encoded message
   if (typeof err.message === 'string') {
@@ -56,6 +65,10 @@ class Database {
   constructor(db) {
     this.db = db;
     this.memory = this.db.memory
+
+    /** @type boolean */
+    this.inTransaction;
+
     Object.defineProperties(this, {
       inTransaction: {
         get() {
@@ -94,7 +107,15 @@ class Database {
   /**
    * Returns a function that executes the given function in a transaction.
    *
-   * @param {function} fn - The function to wrap in a transaction.
+   * @template {VariableArgFunction} F
+   * @param {F} fn - The function to wrap in a transaction.
+   * @returns {{
+   *  (...bindParameters: ArgumentTypes<F>): Promise<ReturnType<F>>;
+   *  default(...bindParameters: ArgumentTypes<F>): Promise<ReturnType<F>>;
+   *  deferred(...bindParameters: ArgumentTypes<F>): Promise<ReturnType<F>>;
+   *  immediate(...bindParameters: ArgumentTypes<F>): Promise<ReturnType<F>>;
+   *  exclusive(...bindParameters: ArgumentTypes<F>): Promise<ReturnType<F>>;
+   * }}
    */
   transaction(fn) {
     if (typeof fn !== "function")