remove yallist from parse, but NOT from pack

We actually do lean on the logic of the linked list nodes internal
references to keep PackJob tasks in order, even as the head of the list
moves on when jobs complete, so a simple Array.shift() isn't sufficient.

Close: #401

Author: isaacs

src/pack.ts

@@ -92,6 +92,14 @@ export class Pack
 
   [WRITEENTRYCLASS]: typeof WriteEntry | typeof WriteEntrySync
   onWriteEntry?: (entry: WriteEntry) => void;
+  // Note: we actually DO need a linked list here, because we
+  // shift() to update the head of the list where we start, but still
+  // while that happens, need to know what the next item in the queue
+  // will be. Since we do multiple jobs in parallel, it's not as simple
+  // as just an Array.shift(), since that would lose the information about
+  // the next job in the list. We could add a .next field on the PackJob
+  // class, but then we'd have to be tracking the tail of the queue the
+  // whole time, and Yallist just does that for us anyway.
   [QUEUE]: Yallist<PackJob>;
   [JOBS]: number = 0;
   [PROCESSING]: boolean = false;

src/parse.ts

@@ -2,7 +2,7 @@
 // the full 512 bytes of a header to come in.  We will Buffer.concat()
 // it to the next write(), which is a mem copy, but a small one.
 //
-// this[QUEUE] is a Yallist of entries that haven't been emitted
+// this[QUEUE] is a list of entries that haven't been emitted
 // yet this can only get filled up if the user keeps write()ing after
 // a write() returns false, or does a write() with more than one entry
 //
@@ -20,7 +20,6 @@
 
 import { EventEmitter as EE } from 'events'
 import { BrotliDecompress, Unzip } from 'minizlib'
-import { Yallist } from 'yallist'
 import { Header } from './header.js'
 import { TarOptions } from './options.js'
 import { Pax } from './pax.js'
@@ -79,8 +78,7 @@ export class Parser extends EE implements Warner {
   writable: true = true
   readable: false = false;
 
-  [QUEUE]: Yallist<ReadEntry | [string | symbol, any, any]> =
-    new Yallist();
+  [QUEUE]: (ReadEntry | [string | symbol, any, any])[] = [];
   [BUFFER]?: Buffer;
   [READENTRY]?: ReadEntry;
   [WRITEENTRY]?: ReadEntry;