fix (cspell-tools): normalize .gz output (#4796)

packages/cspell-tools/src/app.test.ts

@@ -1,7 +1,7 @@
 import * as Commander from 'commander';
 import * as fs from 'fs/promises';
 import * as path from 'path';
-import { beforeAll, beforeEach, describe, expect, test, vi } from 'vitest';
+import { afterEach, beforeAll, beforeEach, describe, expect, test, vi } from 'vitest';
 
 import * as app from './app.js';
 import { readTextFile } from './compiler/readers/readTextFile.js';
@@ -10,10 +10,14 @@ import { compressFile } from './gzip/compressFiles.js';
 import { spyOnConsole } from './test/console.js';
 import { createTestHelper } from './test/TestHelper.js';
 
-vi.mock('./gzip/compressFiles.js', () => ({
-    compressFile: vi.fn().mockImplementation((name: string) => Promise.resolve(name + '.gz')),
-    OSFlags: { Unix: 3 },
-}));
+vi.mock('./gzip/compressFiles.js', async () => {
+    // eslint-disable-next-line @typescript-eslint/consistent-type-imports
+    const mod = await vi.importActual<typeof import('./gzip/compressFiles.js')>('./gzip/compressFiles.js');
+    return {
+        ...mod,
+        compressFile: vi.fn().mockImplementation((name: string) => Promise.resolve(name + '.gz')),
+    };
+});
 
 const OSFlags = {
     Unix: 3,
@@ -53,9 +57,11 @@ describe('Validate the application', () => {
     beforeEach(() => {
         testHelper.createTempDir();
         testHelper.cp(path.join(pathSamples, 'cities.txt'), '.');
-        vi.resetAllMocks();
         consoleSpy.attach();
     });
+    afterEach(() => {
+        vi.resetAllMocks();
+    });
 
     test('app compile-trie', async () => {
         const commander = getCommander();

packages/cspell-tools/src/compiler/readers/readTextFile.ts

@@ -1,20 +1,23 @@
+import assert from 'assert';
 import { promises as fs } from 'fs';
-import { promisify } from 'util';
-import * as zlib from 'zlib';
 
-const gunzip = promisify(zlib.gunzip);
+import { decompress } from '../../gzip/index.js';
 
 const isGzFile = /\.gz$/;
 
 export function readTextFile(filename: string): Promise<string> {
     const content = fs
         .readFile(filename)
-        .then((buffer) => (isGzFile.test(filename) ? gunzip(buffer) : buffer))
-        .then((buffer) => buffer.toString('utf8'));
+        .then(async (buffer) => (isGzFile.test(filename) ? decompress(buffer) : buffer))
+        .then((buffer) => (assertIsBuffer(buffer), buffer.toString('utf8')));
     return content;
 }
 
 export async function readTextFileLines(filename: string): Promise<string[]> {
     const content = await readTextFile(filename);
     return content.split('\n');
 }
+
+function assertIsBuffer(value: unknown): asserts value is Buffer {
+    assert(Buffer.isBuffer(value));
+}

packages/cspell-tools/src/compiler/writeTextToFile.ts

@@ -1,15 +1,13 @@
 import { promises as fs } from 'fs';
-import { promisify } from 'util';
-import * as zlib from 'zlib';
 
-const gzip = promisify(zlib.gzip);
+import { compress } from '../gzip/index.js';
 
 const isGzFile = /\.gz$/;
 
 export async function writeTextToFile(filename: string, data: string): Promise<void> {
     const useGz = isGzFile.test(filename);
     const buf = Buffer.from(data, 'utf-8');
-    const buffer = useGz ? await gzip(buf) : buf;
+    const buffer = useGz ? await compress(buf) : buf;
     await fs.writeFile(filename, buffer);
 }
 

packages/cspell-tools/src/gzip/compressFiles.test.ts

@@ -1,9 +1,8 @@
 import { readFile, writeFile } from 'node:fs/promises';
-import { gzipSync } from 'node:zlib';
 
 import { describe, expect, test, vi } from 'vitest';
 
-import { compress, compressFile, decompress, OSFlags } from './compressFiles.js';
+import { compress, compressFile, compressSync, decompress, OSFlags } from './compressFiles.js';
 
 const content = `
 Have a nice day.
@@ -21,15 +20,17 @@ describe('compressFiles', () => {
     test('compressFile', async () => {
         await compressFile('README.md');
         expect(mockReadFile).toHaveBeenLastCalledWith('README.md');
-        expect(mockWriteFile).toHaveBeenLastCalledWith('README.md.gz', gzipSync(content));
+        expect(mockWriteFile).toHaveBeenLastCalledWith('README.md.gz', compressSync(content));
     });
 
     test('compress/decompress string', async () => {
-        const gzBufA = await compress(content);
+        const gzBufA = await compress(content, OSFlags.auto);
         const gzBufB = await compress(content, OSFlags.NTFS);
         const gzBufC = await compress(content, OSFlags.Unix);
+        const gzBufDef = await compress(content);
 
         expect(gzBufB).not.toEqual(gzBufC);
+        expect(gzBufDef).toEqual(gzBufC);
 
         const strA = await decompress(gzBufA, 'utf8');
         const strB = await decompress(gzBufB, 'utf8');

packages/cspell-tools/src/gzip/compressFiles.ts

@@ -1,11 +1,12 @@
 import { readFile, writeFile } from 'node:fs/promises';
 import { promisify } from 'node:util';
-import { gunzip as gunzipCB, gzip as gz } from 'node:zlib';
+import { gunzip as gunzipCB, gzip as gz, gzipSync } from 'node:zlib';
 
 const gzip = promisify(gz);
 const gunzip = promisify(gunzipCB);
 
 export enum OSFlags {
+    auto = -1,
     FAT = 0,
     Unix = 3,
     HPFS = 6, // cspell:ignore hpfs
@@ -28,11 +29,19 @@ export async function compressFile(file: string, os?: OSFlags): Promise<string>
 }
 
 export async function compress(buf: string | Uint8Array | Buffer, os?: OSFlags): Promise<Uint8Array> {
-    const zBuf = await gzip(buf);
-    const osFlag = os ?? zBuf[OSSystemIDOffset];
+    return fixOSSystemID(await gzip(buf), os);
+}
+
+export function compressSync(buf: string | Uint8Array | Buffer, os?: OSFlags): Uint8Array {
+    return fixOSSystemID(gzipSync(buf), os);
+}
+
+function fixOSSystemID(zBuf: Uint8Array, os: OSFlags = OSFlags.Unix): Uint8Array {
+    const osFlag = os == OSFlags.auto ? zBuf[OSSystemIDOffset] : os;
     zBuf[OSSystemIDOffset] = osFlag;
     return zBuf;
 }
+
 export async function decompress(buf: Uint8Array | Buffer, encoding?: undefined): Promise<Uint8Array>;
 export async function decompress(buf: Uint8Array | Buffer, encoding: 'utf8'): Promise<string>;
 export async function decompress(buf: Uint8Array | Buffer, encoding: 'utf8' | undefined): Promise<string | Uint8Array>;

packages/cspell-tools/src/gzip/index.ts

@@ -1,2 +1,2 @@
-export { compressFile, OSFlags } from './compressFiles.js';
+export { compress, compressFile, decompress, OSFlags } from './compressFiles.js';
 export { gzip } from './gzip.js';