add onWriteEntry method

fix: #316

src/options.ts

@@ -4,6 +4,7 @@ import { type GzipOptions, type ZlibOptions } from 'minizlib'
 import { type Stats } from 'node:fs'
 import { type ReadEntry } from './read-entry.js'
 import { type WarnData } from './warn-method.js'
+import { WriteEntry } from './write-entry.js'
 
 const argmap = new Map<keyof TarOptionsWithAliases, keyof TarOptions>(
   [
@@ -275,6 +276,16 @@ export interface TarOptions {
    */
   noResume?: boolean
 
+  /**
+   * When creating, updating, or replacing within archives, this method will
+   * be called with each WriteEntry that is created.
+   *
+   * It's not called 'onentry' because that's already taken for the ReadEntry
+   * when reading archives, and it's just easier to only have one type of
+   * options object that this whole library can pass around without issue.
+   */
+  onWriteEntry?: (entry: WriteEntry) => any
+
   /**
    * When extracting or listing archives, this method will be called with
    * each entry that is not excluded by a `filter`.

src/pack.ts

@@ -92,6 +92,7 @@ export class Pack
   jobs: number;
 
   [WRITEENTRYCLASS]: typeof WriteEntry | typeof WriteEntrySync;
+  onWriteEntry?: (entry: WriteEntry) => void
   [QUEUE]: Yallist<PackJob>;
   [JOBS]: number = 0;
   [PROCESSING]: boolean = false;
@@ -110,6 +111,7 @@ export class Pack
     this.linkCache = opt.linkCache || new Map()
     this.statCache = opt.statCache || new Map()
     this.readdirCache = opt.readdirCache || new Map()
+    this.onWriteEntry = opt.onWriteEntry
 
     this[WRITEENTRYCLASS] = WriteEntry
     if (typeof opt.onwarn === 'function') {
@@ -154,7 +156,7 @@ export class Pack
     if (opt.mtime) this.mtime = opt.mtime
 
     this.filter =
-      typeof opt.filter === 'function' ? opt.filter : _ => true
+      typeof opt.filter === 'function' ? opt.filter : () => true
 
     this[QUEUE] = new Yallist<PackJob>()
     this[JOBS] = 0
@@ -385,8 +387,9 @@ export class Pack
   [ENTRY](job: PackJob) {
     this[JOBS] += 1
     try {
-      return new this[WRITEENTRYCLASS](job.path, this[ENTRYOPT](job))
-        .on('end', () => this[JOBDONE](job))
+      const e = new this[WRITEENTRYCLASS](job.path, this[ENTRYOPT](job))
+      this.onWriteEntry?.(e)
+      return e.on('end', () => this[JOBDONE](job))
         .on('error', er => this.emit('error', er))
     } catch (er) {
       this.emit('error', er)

test/pack.js

@@ -56,7 +56,8 @@ t.test('set up', t => {
 
 t.test('pack a file', t => {
   const out = []
-  new Pack({ cwd: files })
+  const seen = []
+  new Pack({ cwd: files, onWriteEntry: e => seen.push(e) })
     .end('one-byte.txt')
     .on('data', c => out.push(c))
     .on('end', _ => {
@@ -98,6 +99,7 @@ t.test('pack a file', t => {
       )
       const hs = new Header(sync)
       t.match(hs, expect)
+      t.strictSame(seen.map(e => e.path), ['one-byte.txt'])
       t.end()
     })
 })