Merge pull request #5655 from Snuffleupagus/issue-5644

Avoid getting stuck in empty nodes in the Pages tree when calling |Catalog_getPageDict| (issue 5644)

src/core/obj.js

@@ -597,6 +597,7 @@ var Catalog = (function CatalogClosure() {
       var nodesToVisit = [this.catDict.getRaw('Pages')];
       var currentPageIndex = 0;
       var xref = this.xref;
+      var checkAllKids = false;
 
       function next() {
         while (nodesToVisit.length) {
@@ -604,7 +605,7 @@ var Catalog = (function CatalogClosure() {
 
           if (isRef(currentNode)) {
             xref.fetchAsync(currentNode).then(function (obj) {
-              if ((isDict(obj, 'Page') || (isDict(obj) && !obj.has('Kids')))) {
+              if (isDict(obj, 'Page') || (isDict(obj) && !obj.has('Kids'))) {
                 if (pageIndex === currentPageIndex) {
                   capability.resolve([obj, currentNode]);
                 } else {
@@ -619,12 +620,17 @@ var Catalog = (function CatalogClosure() {
             return;
           }
 
-          // must be a child page dictionary
+          // Must be a child page dictionary.
           assert(
             isDict(currentNode),
             'page dictionary kid reference points to wrong type of object'
           );
           var count = currentNode.get('Count');
+          // If the current node doesn't have any children, avoid getting stuck
+          // in an empty node further down in the tree (see issue5644.pdf).
+          if (count === 0) {
+            checkAllKids = true;
+          }
           // Skip nodes where the page can't be.
           if (currentPageIndex + count <= pageIndex) {
             currentPageIndex += count;
@@ -633,7 +639,7 @@ var Catalog = (function CatalogClosure() {
 
           var kids = currentNode.get('Kids');
           assert(isArray(kids), 'page dictionary kids object is not an array');
-          if (count === kids.length) {
+          if (!checkAllKids && count === kids.length) {
             // Nodes that don't have the page have been skipped and this is the
             // bottom of the tree which means the page requested must be a
             // descendant of this pages node. Ideally we would just resolve the

test/pdfs/issue5644.pdf.link

@@ -0,0 +1 @@
+http://web.archive.org/web/20140703204310/http://repository.readscheme.org/ftp/papers/sw2010/06-barland.pdf

test/test_manifest.json

@@ -833,6 +833,15 @@
        "link": false,
        "type": "eq"
     },
+    {  "id": "issue5644",
+       "file": "pdfs/issue5644.pdf",
+       "md5": "6f9313c5043b3ecb0ab2df321d3e1847",
+       "rounds": 1,
+       "link": true,
+       "firstPage": 1,
+       "lastPage": 6,
+       "type": "eq"
+    },
     {  "id": "bug866395",
        "file": "pdfs/bug866395.pdf",
        "md5": "f03bc77e84637241980b09a0a220f575",