Properly handle long linkpath in PaxHeader

tar-stream creates some interesting tarballs, but they are technically
allowed, and should be handled properly.

Fix: isaacs#312

Also, this cleans up a flaky race condition in the unpack test.

Author: isaacs

src/parse.ts

@@ -199,6 +199,7 @@ export class Parser extends EE implements Warner {
           })
         } else if (
           !/^(Symbolic)?Link$/.test(type) &&
+          !/^(Global)?ExtendedHeader$/.test(type) &&
           header.linkpath
         ) {
           this.warn('TAR_ENTRY_INVALID', 'linkpath forbidden', {

test/extract.js

@@ -415,3 +415,17 @@ t.test('brotli', async t => {
     t.end()
   })
 })
+
+t.test('verify long linkname is not a problem', async t => {
+  // See: https://github.com/isaacs/node-tar/issues/312
+  const file = path.resolve(__dirname, 'fixtures/long-linkname.tar')
+  t.test('sync', t => {
+    x({ sync: true, strict: true, file, C: t.testdir({}) })
+    t.ok(fs.lstatSync(t.testdirName + '/test').isSymbolicLink())
+    t.end()
+  })
+  t.test('async', async t => {
+    await x({ file, C: t.testdir({}), strict: true })
+    t.ok(fs.lstatSync(t.testdirName + '/test').isSymbolicLink())
+  })
+})

test/fixtures/long-linkname.tar

@@ -1821,11 +1821,12 @@ t.test('set owner', t => {
           if (!warned) {
             warned = true
             t.equal(er, poop)
-            t.end()
           }
         },
       })
       u.end(data)
+      t.equal(warned, true)
+      t.end()
     })
 
     t.test('async', t => {
@@ -1838,10 +1839,13 @@ t.test('set owner', t => {
           if (!warned) {
             warned = true
             t.equal(er, poop)
-            t.end()
           }
         },
       })
+      u.on('finish', () => {
+        t.equal(warned, true)
+        t.end()
+      })
       u.end(data)
     })