Fix annotation border style parsing by handling empty dash arrays

src/core/annotation.js

@@ -1474,9 +1474,9 @@ class AnnotationBorderStyle {
     // We validate the dash array, but we do not use it because CSS does not
     // allow us to change spacing of dashes. For more information, visit
     // http://www.w3.org/TR/css3-background/#the-border-style.
-    if (Array.isArray(dashArray) && dashArray.length > 0) {
-      // According to the PDF specification: the elements in `dashArray`
-      // shall be numbers that are nonnegative and not all equal to zero.
+    if (Array.isArray(dashArray)) {
+      // The PDF specification states that elements in the dash array, if
+      // present, must be non-negative numbers and must not all equal zero.
       let isValid = true;
       let allZeros = true;
       for (const element of dashArray) {
@@ -1488,7 +1488,7 @@ class AnnotationBorderStyle {
           allZeros = false;
         }
       }
-      if (isValid && !allZeros) {
+      if (dashArray.length === 0 || (isValid && !allZeros)) {
         this.dashArray = dashArray;
 
         if (forceStyle) {

test/pdfs/.gitignore

@@ -514,6 +514,7 @@
 !issue11549_reduced.pdf
 !issue8097_reduced.pdf
 !issue15262.pdf
+!issue17904.pdf
 !bug1743245.pdf
 !quadpoints.pdf
 !transparent.pdf

test/test_manifest.json

@@ -3858,6 +3858,14 @@
     "type": "eq",
     "annotations": true
   },
+  {
+    "id": "issue17904",
+    "file": "pdfs/issue17904.pdf",
+    "md5": "4b8f0b565a61bf068ef72d232c997cef",
+    "rounds": 1,
+    "type": "eq",
+    "annotations": true
+  },
   {
     "id": "issue6179_reduced",
     "file": "pdfs/issue6179_reduced.pdf",

test/unit/annotation_spec.js

@@ -549,6 +549,15 @@ describe("annotation", function () {
       expect(borderStyle.dashArray).toEqual([3]);
     });
 
+    it("should not set the width to zero if the dash array is empty (issue 17904)", function () {
+      const borderStyle = new AnnotationBorderStyle();
+      borderStyle.setWidth(3);
+      borderStyle.setDashArray([]);
+
+      expect(borderStyle.width).toEqual(3);
+      expect(borderStyle.dashArray).toEqual([]);
+    });
+
     it("should set and get a valid horizontal corner radius", function () {
       const borderStyle = new AnnotationBorderStyle();
       borderStyle.setHorizontalCornerRadius(3);