refactors to correctly check if dates are equal

lib/mixins/attachments.js

@@ -105,11 +105,13 @@ export default {
 
 /** check two embedded file metadata objects for equality */
 function isEqual(a, b) {
-  return (
+  const result = (
     a.Subtype === b.Subtype &&
     a.Params.CheckSum.toString() === b.Params.CheckSum.toString() &&
     a.Params.Size === b.Params.Size &&
-    a.Params.CreationDate === b.Params.CreationDate &&
-    a.Params.ModDate === b.Params.ModDate
+    a.Params.CreationDate.toISOString() === b.Params.CreationDate.toISOString() &&
+    a.Params.ModDate.toISOString() === b.Params.ModDate.toISOString()
   );
+  console.log('isEqual', result);
+  return result;
 }

tests/unit/attachments.spec.js

@@ -166,6 +166,7 @@ describe('file', () => {
 
   test('attach multiple files', () => {
     const docData = logData(document);
+    const duplicateDate = new Date(date)
 
     document.file(Buffer.from('example text'), {
       name: 'file1.txt',
@@ -192,6 +193,41 @@ describe('file', () => {
     (file2.txt) 11 0 R
 ]
 >>
+>>`
+    ]);
+  });
+
+  test('attach the same file multiple times', () => {
+    const docData = logData(document);
+
+    document.file(Buffer.from('example text'), {
+      name: 'file1.txt',
+      creationDate: date,
+      modifiedDate: date
+    });
+    document.file(Buffer.from('example text'), {
+      name: 'file1.txt',
+      creationDate: new Date(date),
+      modifiedDate: new Date(date)
+    });
+    document.end();
+
+    const numFiles = docData.filter((str) => typeof str === 'string' && str.startsWith('<<\n/Type /EmbeddedFile\n'))
+
+    expect(numFiles.length).toEqual(1)
+
+    expect(docData).toContainChunk([
+      `2 0 obj`,
+      `<<
+/Dests <<
+  /Names [
+]
+>>
+/EmbeddedFiles <<
+  /Names [
+    (file1.txt) 10 0 R
+]
+>>
 >>`
     ]);
   });