[Bug]: UnknownErrorException: parent.get is not a function

[gsamokovarov]

Attach (recommended) or Link to PDF file

While rendering a specific document I get the following error. The controls I use in my case seem to work: zoom {in,out,reset}, page controls and print. I can send the document privately.

Web browser and its version

'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36'

Operating system and its version

macOS

PDF.js version

v5.1.91

Is the bug present in the latest PDF.js version?

Yes

Is a browser extension

No

Steps to reproduce the problem

1. Open specific PDF document. I will send it privately.

What is the expected behavior?

Not raising an error.

What went wrong?

An error while decoding a PDF document.

Link to a viewer

No response

Additional context

No response

[Snuffleupagus]

I can send the document privately.

Sorry, but please note that we need publicly available test-cases to make issues actionable/valid for any contributor.

(Also, please provide error messages as text rather than images.)

[gsamokovarov]

I have this happnening in a customer document, I cannot publicly share it, or have the expertise to reproduce the error in another document. I have sent the document privately to @calixteman.

I was able to debug the problem down to StructTreeNode.addPage:

pdf.js/src/core/struct_tree.js

Lines 758 to 760 in 2f7d163

	const parent = dict.get("P");
	if (!parent || isName(parent.get("Type"), "StructTreeRoot")) {

For this particular document parent.get (at some point) gives us an object of CCITTFaxStream type that doesn't have a get method.

[Snuffleupagus]

Closing, since the PR referenced above is probably the only thing that can be done without a test-case.

[gsamokovarov]

It is fixed for the documents we were hitting this.