From 5d902244093970d9e4f0896f6cac7f83351484ee Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Wed, 16 Jan 2019 11:30:36 +0100
Subject: [PATCH 1/2] Add a unit-test for issue 10395 (PR 10398 follow-up)

---
 test/unit/metadata_spec.js | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/test/unit/metadata_spec.js b/test/unit/metadata_spec.js
index 01a992702..2abadc139 100644
--- a/test/unit/metadata_spec.js
+++ b/test/unit/metadata_spec.js
@@ -128,6 +128,37 @@ describe('metadata', function() {
     expect(isEmptyObj(metadata.getAll())).toEqual(true);
   });
 
+  it('should gracefully handle "junk" before the actual metadata (issue 10395)',
+      function() {
+    const data = '<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>' +
+      '<x:xmpmeta x:xmptk="TallComponents PDFObjects 1.0" ' +
+      'xmlns:x="adobe:ns:meta/">' +
+      '<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">' +
+      '<rdf:Description rdf:about="" ' +
+      'xmlns:pdf="http://ns.adobe.com/pdf/1.3/">' +
+      '<pdf:Producer>PDFKit.NET 4.0.102.0</pdf:Producer>' +
+      '<pdf:Keywords></pdf:Keywords>' +
+      '<pdf:PDFVersion>1.7</pdf:PDFVersion></rdf:Description>' +
+      '<rdf:Description rdf:about="" ' +
+      'xmlns:xap="http://ns.adobe.com/xap/1.0/">' +
+      '<xap:CreateDate>2018-12-27T13:50:36-08:00</xap:CreateDate>' +
+      '<xap:ModifyDate>2018-12-27T13:50:38-08:00</xap:ModifyDate>' +
+      '<xap:CreatorTool></xap:CreatorTool>' +
+      '<xap:MetadataDate>2018-12-27T13:50:38-08:00</xap:MetadataDate>' +
+      '</rdf:Description><rdf:Description rdf:about="" ' +
+      'xmlns:dc="http://purl.org/dc/elements/1.1/">' +
+      '<dc:creator><rdf:Seq><rdf:li></rdf:li></rdf:Seq></dc:creator>' +
+      '<dc:subject><rdf:Bag /></dc:subject>' +
+      '<dc:description><rdf:Alt><rdf:li xml:lang="x-default">' +
+      '</rdf:li></rdf:Alt></dc:description>' +
+      '<dc:title><rdf:Alt><rdf:li xml:lang="x-default"></rdf:li>' +
+      '</rdf:Alt></dc:title><dc:format>application/pdf</dc:format>' +
+      '</rdf:Description></rdf:RDF></x:xmpmeta><?xpacket end="w"?>';
+    const metadata = new Metadata(data);
+
+    expect(isEmptyObj(metadata.getAll())).toEqual(true);
+  });
+
   it('should correctly handle metadata containing "&apos" (issue 10407)',
       function() {
     const data = '<x:xmpmeta xmlns:x=\'adobe:ns:meta/\'>' +

From 9f45f8dfdaed3f399f594050354db982f900759b Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Wed, 16 Jan 2019 12:37:21 +0100
Subject: [PATCH 2/2] When parsing Metadata, attempt to remove "junk" before
 the first tag (PR 10398 follow-up)

This will allow the Metadata to be successfully extracted from the PDF file in issue 10395.
Furthermore, this patch also fixes a bug in `Metadata.get` which causes the method to return `null` rather than an empty string or zero (since either ought to be allowed).
---
 src/display/metadata.js    |  7 +++++--
 test/unit/metadata_spec.js | 21 ++++++++++++++++++++-
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/src/display/metadata.js b/src/display/metadata.js
index 5c7922bf4..eaa3ebdc9 100644
--- a/src/display/metadata.js
+++ b/src/display/metadata.js
@@ -35,7 +35,9 @@ class Metadata {
   }
 
   _repair(data) {
-    return data.replace(/>\\376\\377([^<]+)/g, function(all, codes) {
+    // Start by removing any "junk" before the first tag (see issue 10395).
+    return data.replace(/^([^<]+)/, '').replace(/>\\376\\377([^<]+)/g,
+        function(all, codes) {
       let bytes = codes.replace(/\\([0-3])([0-7])([0-7])/g,
           function(code, d1, d2, d3) {
         return String.fromCharCode(d1 * 64 + d2 * 8 + d3 * 1);
@@ -104,7 +106,8 @@ class Metadata {
   }
 
   get(name) {
-    return this._metadata[name] || null;
+    const data = this._metadata[name];
+    return (typeof data !== 'undefined' ? data : null);
   }
 
   getAll() {
diff --git a/test/unit/metadata_spec.js b/test/unit/metadata_spec.js
index 2abadc139..b88d31c1d 100644
--- a/test/unit/metadata_spec.js
+++ b/test/unit/metadata_spec.js
@@ -156,7 +156,26 @@ describe('metadata', function() {
       '</rdf:Description></rdf:RDF></x:xmpmeta><?xpacket end="w"?>';
     const metadata = new Metadata(data);
 
-    expect(isEmptyObj(metadata.getAll())).toEqual(true);
+    expect(metadata.has('dc:title')).toBeTruthy();
+    expect(metadata.has('dc:qux')).toBeFalsy();
+
+    expect(metadata.get('dc:title')).toEqual('');
+    expect(metadata.get('dc:qux')).toEqual(null);
+
+    expect(metadata.getAll()).toEqual({
+      'dc:creator': '',
+      'dc:description': '',
+      'dc:format': 'application/pdf',
+      'dc:subject': '',
+      'dc:title': '',
+      'pdf:keywords': '',
+      'pdf:pdfversion': '1.7',
+      'pdf:producer': 'PDFKit.NET 4.0.102.0',
+      'xap:createdate': '2018-12-27T13:50:36-08:00',
+      'xap:creatortool': '',
+      'xap:metadatadate': '2018-12-27T13:50:38-08:00',
+      'xap:modifydate': '2018-12-27T13:50:38-08:00',
+    });
   });
 
   it('should correctly handle metadata containing "&apos" (issue 10407)',