chore: fixed up header type mappings

Author: aryanjassal

src/Generator.ts

@@ -1,6 +1,7 @@
 import type { TarType, DirectoryContent } from './types';
 import fs from 'fs';
 import path from 'path';
+import { TarTypes } from './types';
 import * as errors from './errors';
 
 /**
@@ -23,7 +24,7 @@ function createHeader(filePath: string, stat: fs.Stats, type: TarType): Buffer {
     );
   }
 
-  const size = type === '0' ? stat.size : 0;
+  const size = type === TarTypes.FILE ? stat.size : 0;
   const header = Buffer.alloc(BLOCK_SIZE, 0);
 
   // The TAR headers follow this structure
@@ -47,7 +48,6 @@ function createHeader(filePath: string, stat: fs.Stats, type: TarType): Buffer {
   // 345      155     File name (last 155 bytes, total 255 bytes, null-padded)
   // 500      12      '\0' (unused)
 
-  // FIXME: Assuming file path is under 100 characters long
   header.write(filePath.slice(0, 99).padEnd(100, '\0'), 0, 100, 'utf8');
   header.write(stat.mode.toString(8).padStart(7, '0') + '\0', 100, 12, 'ascii');
   header.write(stat.uid.toString(8).padStart(7, '0') + '\0', 108, 12, 'ascii');
@@ -109,10 +109,10 @@ async function* walkDirectory(
     const tarPath = path.join(relativePath, entry);
 
     if (stat.isDirectory()) {
-      yield { path: tarPath + '/', stat: stat, type: '5' };
+      yield { path: tarPath + '/', stat: stat, type: TarTypes.DIRECTORY };
       yield* walkDirectory(baseDir, path.join(relativePath, entry));
     } else if (stat.isFile()) {
-      yield { path: tarPath, stat: stat, type: '0' };
+      yield { path: tarPath, stat: stat, type: TarTypes.FILE };
     }
   }
 }
@@ -122,7 +122,7 @@ async function* createTar(baseDir: string): AsyncGenerator<Buffer, void, void> {
     // Create header
     yield createHeader(entry.path, entry.stat, entry.type);
 
-    if (entry.type === '0') {
+    if (entry.type === TarTypes.FILE) {
       // Get file contents
       yield* readFile(path.join(baseDir, entry.path));
     }
@@ -133,14 +133,4 @@ async function* createTar(baseDir: string): AsyncGenerator<Buffer, void, void> {
   yield Buffer.alloc(BLOCK_SIZE, 0);
 }
 
-// NOTE: probably need to remove this, idk
-//  this is a library and should only worry about tarring itself and not writing to fs
-async function writeArchive(inputFile: string, outputFile: string) {
-  const fileHandle = await fs.promises.open(outputFile, 'w+');
-  for await (const chunk of createTar(inputFile)) {
-    await fileHandle.write(chunk);
-  }
-  await fileHandle.close();
-}
-
-export { createHeader, readFile, createTar, writeArchive };
+export { createHeader, readFile, createTar };

src/types.ts

@@ -1,19 +1,17 @@
 import type { Stats } from 'fs';
 
-// FIXME: Using 0s and 5s for files and directories isn't a good way to handle
-//  this. I need to make it simpler so that I can assign and test using strings.
-//  A potential solution is enums, but they don't work with types, so it's a bit
-//  weird.
-type TarFile = '0';
+const TarTypes = {
+  FILE: '0',
+  DIRECTORY: '5',
+} as const;
 
-type TarDirectory = '5';
-
-type TarType = TarFile | TarDirectory;
+type TarType = (typeof TarTypes)[keyof typeof TarTypes];
 
 type DirectoryContent = {
   path: string;
   stat: Stats;
   type: TarType;
 };
 
-export type { TarFile, TarDirectory, TarType, DirectoryContent };
+export type { TarType, DirectoryContent };
+export { TarTypes };

tests/index.test.ts

@@ -1,9 +1,24 @@
-import { writeArchive } from '@/Generator';
+import fs from 'fs';
+import { createTar } from '@/Generator';
 
+// TODO: actually write tests
 describe('index', () => {
-  test.skip('test', async () => {
-    await expect(
-      writeArchive('/home/aryanj/Downloads', '/home/aryanj/archive.tar'),
-    ).toResolve();
+  test('test', async () => {
+    if (process.env['CI'] != null) {
+      // Skip this test if on CI
+      expect(true).toEqual(true);
+    } else {
+      // Otherwise, run the test which creates a test archive
+      const writeArchive = async (inputFile: string, outputFile: string) => {
+        const fileHandle = await fs.promises.open(outputFile, 'w+');
+        for await (const chunk of createTar(inputFile)) {
+          await fileHandle.write(chunk);
+        }
+        await fileHandle.close();
+      };
+      await expect(
+        writeArchive('/home/aryanj/Downloads', '/home/aryanj/archive.tar'),
+      ).toResolve();
+    }
   }, 60000);
 });