Export more constants

.gitignore

@@ -5,4 +5,4 @@ coverage
 .vscode
 .DS_Store
 /*.parquet
-types
+/types

README.md

@@ -180,6 +180,10 @@ await parquetRead({
 
 The `parquetReadObjects` function defaults to returning an array of objects.
 
+## Parquet Writing
+
+To create parquet files from javascript, check out the [hyparquet-writer](https://github.com/hyparam/hyparquet-writer) package.
+
 ## Supported Parquet Files
 
 The parquet format is known to be a sprawling format which includes options for a wide array of compression schemes, encoding types, and data structures.

package.json

@@ -1,7 +1,7 @@
 {
   "name": "hyparquet",
   "version": "1.10.1",
-  "description": "parquet file parser for javascript",
+  "description": "Parquet file parser for JavaScript",
   "author": "Hyperparam",
   "homepage": "https://hyperparam.app",
   "keywords": [
@@ -43,13 +43,13 @@
     "test": "vitest run"
   },
   "devDependencies": {
-    "@types/node": "22.13.13",
-    "@vitest/coverage-v8": "3.0.9",
+    "@types/node": "22.13.15",
+    "@vitest/coverage-v8": "3.1.1",
     "eslint": "9.23.0",
     "eslint-plugin-jsdoc": "50.6.9",
     "hyparquet-compressors": "1.1.1",
     "typescript": "5.8.2",
-    "typescript-eslint": "8.28.0",
-    "vitest": "3.0.9"
+    "typescript-eslint": "8.29.0",
+    "vitest": "3.1.1"
   }
 }

src/column.js

@@ -128,8 +128,8 @@ export function getColumnRange({ dictionary_page_offset, data_page_offset, total
  * Read parquet header from a buffer.
  *
  * @import {ColumnMetaData, DecodedArray, DataReader, PageHeader, ParquetReadOptions, SchemaTree} from '../src/types.d.ts'
- * @param {DataReader} reader - parquet file reader
- * @returns {PageHeader} metadata object and bytes read
+ * @param {DataReader} reader
+ * @returns {PageHeader}
  */
 function parquetHeader(reader) {
   const header = deserializeTCompactProtocol(reader)

src/constants.js

@@ -10,9 +10,10 @@ export const ParquetType = [
   'FIXED_LEN_BYTE_ARRAY',
 ]
 
+/** @type {import('../src/types.d.ts').Encoding[]} */
 export const Encoding = [
   'PLAIN',
-  undefined,
+  'GROUP_VAR_INT', // deprecated
   'PLAIN_DICTIONARY',
   'RLE',
   'BIT_PACKED', // deprecated
@@ -23,6 +24,7 @@ export const Encoding = [
   'BYTE_STREAM_SPLIT',
 ]
 
+/** @type {import('../src/types.d.ts').FieldRepetitionType[]} */
 export const FieldRepetitionType = [
   'REQUIRED',
   'OPTIONAL',
@@ -74,6 +76,7 @@ export const logicalTypeType = [
   'UUID',
 ]
 
+/** @type {import('../src/types.d.ts').CompressionCodec[]} */
 export const CompressionCodec = [
   'UNCOMPRESSED',
   'SNAPPY',

src/plain.js

@@ -139,7 +139,7 @@ function readPlainDouble(reader, count) {
 function readPlainByteArray(reader, count) {
   const values = new Array(count)
   for (let i = 0; i < count; i++) {
-    const length = reader.view.getInt32(reader.offset, true)
+    const length = reader.view.getUint32(reader.offset, true)
     reader.offset += 4
     values[i] = new Uint8Array(reader.view.buffer, reader.view.byteOffset + reader.offset, length)
     reader.offset += length

src/snappy.js

@@ -14,7 +14,6 @@ const WORD_MASK = [0, 0xff, 0xffff, 0xffffff, 0xffffffff]
  * @param {Uint8Array} toArray destination array
  * @param {number} toPos destination position
  * @param {number} length number of bytes to copy
- * @returns {void}
  */
 function copyBytes(fromArray, fromPos, toArray, toPos, length) {
   for (let i = 0; i < length; i++) {
@@ -28,7 +27,6 @@ function copyBytes(fromArray, fromPos, toArray, toPos, length) {
  *
  * @param {Uint8Array} input compressed data
  * @param {Uint8Array} output output buffer
- * @returns {void}
  */
 export function snappyUncompress(input, output) {
   const inputLength = input.byteLength

src/types.d.ts

@@ -186,6 +186,7 @@ type ColumnCryptoMetaData = Record<string, never>
 
 export type Encoding =
   'PLAIN' |
+  'GROUP_VAR_INT' | // deprecated
   'PLAIN_DICTIONARY' |
   'RLE' |
   'BIT_PACKED' | // deprecated
@@ -209,7 +210,7 @@ export type Compressors = {
   [K in CompressionCodec]?: (input: Uint8Array, outputLength: number) => Uint8Array
 }
 
-interface KeyValue {
+export interface KeyValue {
   key: string
   value?: string
 }

test/snappy.test.js

@@ -3,7 +3,7 @@ import { describe, expect, it } from 'vitest'
 import { snappyUncompress } from '../src/snappy.js'
 
 describe('snappy uncompress', () => {
-  it('decompresses valid input correctly', async () => {
+  it('decompresses valid input correctly', () => {
     const testCases = [
       { compressed: [0x00], expected: '' },
       { compressed: [0x01, 0x00, 0x68], expected: 'h' },
@@ -37,18 +37,16 @@ describe('snappy uncompress', () => {
       { compressed: [ 6, 20, 2, 0, 0, 0, 3, 23], expected: new Uint8Array([2, 0, 0, 0, 3, 23]) },
     ]
 
-    const futures = testCases.map(async ({ compressed, expected }) => {
+    for (const { compressed, expected } of testCases) {
       const output = new Uint8Array(expected.length)
-      await snappyUncompress(new Uint8Array(compressed), output)
+      snappyUncompress(new Uint8Array(compressed), output)
       if (typeof expected === 'string') {
         const outputStr = new TextDecoder().decode(output)
         expect(outputStr).toBe(expected)
       } else {
         expect(output).toEqual(expected) // Uint8Array
       }
-    })
-
-    await Promise.all(futures)
+    }
   })
 
   it('decompress hyparquet.jpg.snappy', async () => {