From 9db378de2fe679b3a591ad16c2de85501ccc838d Mon Sep 17 00:00:00 2001
From: Kenny Daniel <platypii@gmail.com>
Date: Tue, 28 May 2024 14:24:12 -0700
Subject: [PATCH] toJson tests

---
 src/utils.js       |  4 +---
 test/utils.test.js | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 3 deletions(-)
 create mode 100644 test/utils.test.js

diff --git a/src/utils.js b/src/utils.js
index 5f7197e..75cfed4 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -1,7 +1,5 @@
 /**
- * Replace bigints with numbers.
- * When parsing parquet files, bigints are used to represent 64-bit integers.
- * However, JSON does not support bigints, so it's helpful to convert to numbers.
+ * Replace bigint, date, etc with legal JSON types.
  *
  * @param {any} obj object to convert
  * @returns {unknown} converted object
diff --git a/test/utils.test.js b/test/utils.test.js
new file mode 100644
index 0000000..8906a21
--- /dev/null
+++ b/test/utils.test.js
@@ -0,0 +1,39 @@
+import { describe, expect, it } from 'vitest'
+import { toJson } from '../src/utils.js'
+
+describe('toJson', () => {
+  it('convert undefined to null', () => {
+    expect(toJson(undefined)).toBe(null)
+    expect(toJson(null)).toBe(null)
+  })
+
+  it('convert bigint to number', () => {
+    expect(toJson(BigInt(123))).toBe(123)
+    expect(toJson([BigInt(123), BigInt(456)])).toEqual([123, 456])
+    expect(toJson({ a: BigInt(123), b: { c: BigInt(456) } })).toEqual({ a: 123, b: { c: 456 } })
+  })
+
+  it('convert Uint8Array to array of numbers', () => {
+    expect(toJson(new Uint8Array([1, 2, 3]))).toEqual([1, 2, 3])
+  })
+
+  it('convert Date to ISO string', () => {
+    const date = new Date('2023-05-27T00:00:00Z')
+    expect(toJson(date)).toBe(date.toISOString())
+  })
+
+  it('ignore undefined properties in objects', () => {
+    expect(toJson({ a: undefined, b: BigInt(123) })).toEqual({ b: 123 })
+  })
+
+  it('return null in objects unchanged', () => {
+    expect(toJson({ a: null })).toEqual({ a: null })
+    expect(toJson([null])).toEqual([null])
+  })
+
+  it('return other types unchanged', () => {
+    expect(toJson('string')).toBe('string')
+    expect(toJson(123)).toBe(123)
+    expect(toJson(true)).toBe(true)
+  })
+})