From 9cbf918b35beb69508252d779b3859fa0af0d516 Mon Sep 17 00:00:00 2001
From: "Jorge G. Sancha" <jorge@tinybird.co>
Date: Sat, 7 Mar 2026 14:27:09 +0100
Subject: [PATCH 1/2] fix: prevent jsonPath method from being serialized in
 schema output

When isTypeValidator() returns false due to cross-module Symbol issues,
getColumnJsonPath() fell through to check `column.jsonPath !== undefined`.
Since validators have a jsonPath method, this returned the function itself,
which got stringified in the generated .datasource files.

Fix: check `typeof column.jsonPath === "string"` instead.

Bumps version to 0.0.59.

Fixes #124

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
---
 package.json                  |  2 +-
 src/schema/datasource.test.ts | 12 ++++++++++++
 src/schema/datasource.ts      |  4 +++-
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 6e0832e..bfb1969 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@tinybirdco/sdk",
-  "version": "0.0.58",
+  "version": "0.0.59",
   "description": "TypeScript SDK for Tinybird Forward - define datasources and pipes as TypeScript",
   "type": "module",
   "main": "./dist/index.js",
diff --git a/src/schema/datasource.test.ts b/src/schema/datasource.test.ts
index e5d85c0..63ac174 100644
--- a/src/schema/datasource.test.ts
+++ b/src/schema/datasource.test.ts
@@ -259,6 +259,18 @@ describe("Datasource Schema", () => {
       expect(result).toBeUndefined();
     });
 
+    it("never returns a function even if isTypeValidator fails", () => {
+      // This tests the defensive check - if isTypeValidator incorrectly returns false
+      // for a validator (e.g., due to cross-module Symbol issues), getColumnJsonPath
+      // should still not return the jsonPath method as a value
+      const validator = t.string();
+      const result = getColumnJsonPath(validator);
+
+      // Result should be undefined, not the jsonPath function
+      expect(result).toBeUndefined();
+      expect(typeof result).not.toBe("function");
+    });
+
     it("returns jsonPath from validator modifier", () => {
       const validator = t.string().jsonPath("$.user.id");
       const result = getColumnJsonPath(validator);
diff --git a/src/schema/datasource.ts b/src/schema/datasource.ts
index 8748a44..5cc393d 100644
--- a/src/schema/datasource.ts
+++ b/src/schema/datasource.ts
@@ -272,7 +272,9 @@ export function getColumnJsonPath(column: AnyTypeValidator | ColumnDefinition):
     return getModifiers(column).jsonPath;
   }
 
-  if (column.jsonPath !== undefined) {
+  // Check typeof to avoid returning the jsonPath method from validators
+  // if isTypeValidator incorrectly returns false (e.g., cross-module Symbol issues)
+  if (typeof column.jsonPath === "string") {
     return column.jsonPath;
   }
 

From 5dfe97391917aa2aac825ba8282002438507c2bc Mon Sep 17 00:00:00 2001
From: Rafa Moreno <rmoreno@tinybird.co>
Date: Sat, 7 Mar 2026 15:23:42 +0100
Subject: [PATCH 2/2] test: cover unbranded validator jsonPath fallback

---
 src/schema/datasource.test.ts | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/schema/datasource.test.ts b/src/schema/datasource.test.ts
index 63ac174..bca9594 100644
--- a/src/schema/datasource.test.ts
+++ b/src/schema/datasource.test.ts
@@ -7,7 +7,7 @@ import {
   getColumnNames,
   column,
 } from "./datasource.js";
-import { t } from "./types.js";
+import { t, type AnyTypeValidator } from "./types.js";
 import { engine } from "./engines.js";
 import { defineKafkaConnection, defineS3Connection, defineGCSConnection } from "./connection.js";
 
@@ -259,14 +259,16 @@ describe("Datasource Schema", () => {
       expect(result).toBeUndefined();
     });
 
-    it("never returns a function even if isTypeValidator fails", () => {
-      // This tests the defensive check - if isTypeValidator incorrectly returns false
-      // for a validator (e.g., due to cross-module Symbol issues), getColumnJsonPath
-      // should still not return the jsonPath method as a value
+    it("never returns a function when validator branding is missing", () => {
       const validator = t.string();
-      const result = getColumnJsonPath(validator);
+      // Simulate a validator-like object where isTypeValidator() fails by
+      // removing symbol keys (including the validator brand).
+      const unbrandedValidator = Object.fromEntries(
+        Object.entries(validator as unknown as Record<string, unknown>)
+      ) as unknown as AnyTypeValidator;
+
+      const result = getColumnJsonPath(unbrandedValidator);
 
-      // Result should be undefined, not the jsonPath function
       expect(result).toBeUndefined();
       expect(typeof result).not.toBe("function");
     });