Ensure that TilingPatterns have valid (non-zero) /BBox arrays (issue 8330)

Fixes 8330.

src/core/evaluator.js

@@ -480,30 +480,40 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
                                    stateManager.state.clone());
     },
 
-    handleTilingType:
-        function PartialEvaluator_handleTilingType(fn, args, resources,
-                                                   pattern, patternDict,
-                                                   operatorList, task) {
+    handleTilingType(fn, args, resources, pattern, patternDict, operatorList,
+                     task) {
       // Create an IR of the pattern code.
-      var tilingOpList = new OperatorList();
+      let tilingOpList = new OperatorList();
       // Merge the available resources, to prevent issues when the patternDict
       // is missing some /Resources entries (fixes issue6541.pdf).
-      var resourcesArray = [patternDict.get('Resources'), resources];
-      var patternResources = Dict.merge(this.xref, resourcesArray);
+      let resourcesArray = [patternDict.get('Resources'), resources];
+      let patternResources = Dict.merge(this.xref, resourcesArray);
 
       return this.getOperatorList({
         stream: pattern,
         task,
         resources: patternResources,
         operatorList: tilingOpList,
-      }).then(function () {
-        // Add the dependencies to the parent operator list so they are
-        // resolved before sub operator list is executed synchronously.
-        operatorList.addDependencies(tilingOpList.dependencies);
-        operatorList.addOp(fn, getTilingPatternIR({
+      }).then(function() {
+        return getTilingPatternIR({
           fnArray: tilingOpList.fnArray,
           argsArray: tilingOpList.argsArray,
-        }, patternDict, args));
+        }, patternDict, args);
+      }).then(function(tilingPatternIR) {
+        // Add the dependencies to the parent operator list so they are
+        // resolved before the sub operator list is executed synchronously.
+        operatorList.addDependencies(tilingOpList.dependencies);
+        operatorList.addOp(fn, tilingPatternIR);
+      }, (reason) => {
+        if (this.options.ignoreErrors) {
+          // Error(s) in the TilingPattern -- sending unsupported feature
+          // notification and allow rendering to continue.
+          this.handler.send('UnsupportedFeature',
+                            { featureId: UNSUPPORTED_FEATURES.unknown, });
+          warn(`handleTilingType - ignoring pattern: "${reason}".`);
+          return;
+        }
+        throw reason;
       });
     },
 

src/core/pattern.js

@@ -795,12 +795,18 @@ Shadings.Dummy = (function DummyClosure() {
 })();
 
 function getTilingPatternIR(operatorList, dict, args) {
-  var matrix = dict.getArray('Matrix');
-  var bbox = dict.getArray('BBox');
-  var xstep = dict.get('XStep');
-  var ystep = dict.get('YStep');
-  var paintType = dict.get('PaintType');
-  var tilingType = dict.get('TilingType');
+  let matrix = dict.getArray('Matrix');
+  let bbox = Util.normalizeRect(dict.getArray('BBox'));
+  let xstep = dict.get('XStep');
+  let ystep = dict.get('YStep');
+  let paintType = dict.get('PaintType');
+  let tilingType = dict.get('TilingType');
+
+  // Ensure that the pattern has a non-zero width and height, to prevent errors
+  // in `pattern_helper.js` (fixes issue8330.pdf).
+  if ((bbox[2] - bbox[0]) === 0 || (bbox[3] - bbox[1]) === 0) {
+    throw new Error(`getTilingPatternIR - invalid /BBox array: [${bbox}].`);
+  }
 
   return [
     'TilingPattern', args, operatorList, matrix, bbox, xstep, ystep,

src/display/pattern_helper.js

@@ -304,7 +304,7 @@ var TilingPattern = (function TilingPatternClosure() {
   function TilingPattern(IR, color, ctx, canvasGraphicsFactory, baseTransform) {
     this.operatorList = IR[2];
     this.matrix = IR[3] || [1, 0, 0, 1, 0, 0];
-    this.bbox = Util.normalizeRect(IR[4]);
+    this.bbox = IR[4];
     this.xstep = IR[5];
     this.ystep = IR[6];
     this.paintType = IR[7];