diff --git a/README.md b/README.md
index b942a4a..6a056fb 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 [![minzipped](https://img.shields.io/bundlephobia/minzip/hyparquet-writer)](https://www.npmjs.com/package/hyparquet-writer)
 [![workflow status](https://github.com/hyparam/hyparquet-writer/actions/workflows/ci.yml/badge.svg)](https://github.com/hyparam/hyparquet-writer/actions)
 [![mit license](https://img.shields.io/badge/License-MIT-orange.svg)](https://opensource.org/licenses/MIT)
-![coverage](https://img.shields.io/badge/Coverage-96-darkred)
+![coverage](https://img.shields.io/badge/Coverage-97-darkred)
 [![dependencies](https://img.shields.io/badge/Dependencies-0-blueviolet)](https://www.npmjs.com/package/hyparquet?activeTab=dependencies)
 
 ## Usage
diff --git a/src/schema.js b/src/schema.js
index 62f77e8..2692773 100644
--- a/src/schema.js
+++ b/src/schema.js
@@ -46,7 +46,7 @@ export function getSchemaElementForValues(name, values, type) {
         converted_type = 'JSON'
         valueType = 'BYTE_ARRAY'
       }
-      else if (!valueType) throw new Error(`Cannot determine parquet type for: ${value}`)
+      else if (!valueType) throw new Error(`cannot determine parquet type for: ${value}`)
 
       // expand type if necessary
       if (type === undefined) {
diff --git a/src/write.js b/src/write.js
index 04a52dc..b8827de 100644
--- a/src/write.js
+++ b/src/write.js
@@ -20,7 +20,7 @@ export function parquetWrite({ columnData, compressed = true }) {
   const num_rows = columnData.length ? BigInt(columnData[0].data.length) : 0n
   for (const { data } of columnData) {
     if (BigInt(data.length) !== num_rows) {
-      throw new Error('parquetWrite: all columns must have the same length')
+      throw new Error('columns must have the same length')
     }
   }
 
diff --git a/test/write.test.js b/test/write.test.js
index fa40b12..e4ee465 100644
--- a/test/write.test.js
+++ b/test/write.test.js
@@ -75,13 +75,16 @@ describe('parquetWrite', () => {
   })
 
   it('efficiently serializes column with few distinct values', async () => {
-    const data = Array(10000).fill('aaaa')
+    const data = Array(100000)
+      .fill('aaaa', 0, 50000)
+      .fill('bbbb', 50000, 100000)
     const file = parquetWrite({ columnData: [{ name: 'string', data }] })
-    expect(file.byteLength).toBe(161)
+    expect(file.byteLength).toBe(178)
     // round trip
     const result = await parquetReadObjects({ file })
-    expect(result.length).toBe(10000)
+    expect(result.length).toBe(100000)
     expect(result[0]).toEqual({ string: 'aaaa' })
+    expect(result[50000]).toEqual({ string: 'bbbb' })
   })
 
   it('serializes list types', async () => {
@@ -150,6 +153,25 @@ describe('parquetWrite', () => {
     ])
   })
 
+  it('serializes empty table', async () => {
+    const result = await roundTripDeserialize([])
+    expect(result).toEqual([])
+  })
+
+  it('handles special numeric values', async () => {
+    const data = [
+      { name: 'double', data: [NaN, Infinity, -Infinity, 42, 0, -0] },
+    ]
+    const result = await roundTripDeserialize(data)
+    expect(result[0].double).toBeNaN()
+    expect(result[1].double).toEqual(Infinity)
+    expect(result[2].double).toEqual(-Infinity)
+    expect(result[3].double).toEqual(42)
+    expect(result[4].double).toEqual(0)
+    expect(result[5].double).toEqual(-0)
+    expect(result[5].double).not.toEqual(0)
+  })
+
   it('throws for wrong type specified', () => {
     expect(() => parquetWrite({ columnData: [{ name: 'int', data: [1, 2, 3], type: 'BOOLEAN' }] }))
       .toThrow('parquet cannot write mixed types')
@@ -166,4 +188,16 @@ describe('parquetWrite', () => {
     expect(() => parquetWrite({ columnData: [{ name: 'mixed', data: [1, 2, 3, 'boom'] }] }))
       .toThrow('mixed types not supported')
   })
+
+  it('throws error when columns have mismatched lengths', () => {
+    expect(() => parquetWrite({ columnData: [
+      { name: 'col1', data: [1, 2, 3] },
+      { name: 'col2', data: [4, 5] },
+    ] })).toThrow('columns must have the same length')
+  })
+
+  it('throws error for unsupported data types', () => {
+    expect(() => parquetWrite({ columnData: [{ name: 'func', data: [() => {}] }] }))
+      .toThrow('cannot determine parquet type for: () => {}')
+  })
 })