BibTeX: load_data fails on non-numeric values in the "month" field

[hertg]

Bug Report

When loading a BibTeX file that has a non-numeric month field, the parsing fails.

Here is a BibTeX as provided by the IETF for an RFC (https://datatracker.ietf.org/doc/rfc6749/bibtex/)

@misc{rfc6749,
    series =    {Request for Comments},
    number =    6749,
    howpublished =  {RFC 6749},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC6749},
    url =       {https://www.rfc-editor.org/info/rfc6749},
    author =    {Dick Hardt},
    title =     {{The OAuth 2.0 Authorization Framework}},
    pagetotal = 76,
    year =      2012,
    month =     oct,
    abstract =  {The OAuth 2.0 authorization framework enables a third-party application to obtain limited access to an HTTP service, either on behalf of a resource owner by orchestrating an approval interaction between the resource owner and the HTTP service, or by allowing the third-party application to obtain access on its own behalf. This specification replaces and obsoletes the OAuth 1.0 protocol described in RFC 5849. {[}STANDARDS-TRACK{]}},
}

Using this BibTeX will lead to the build failing. My current workaround is to manually change
the month to its numerical representation (i.e. month = 10 instead of month = oct).

Environment

Zola version: 0.17.2

Expected Behavior

The month field should be parsable, even if it is a three letter abbreviation, which seems to be somewhat common practice.

Current Behavior

Build fails with the following error.

Error: Failed to build the site
Error: Failed to render page '/some/path/content/posts/2023-12-10/index.md'
Error: Reason: Failed to render 'page-template.html'
Error: Reason: Function call 'load_data' failed
Error: Reason: StringVariableNotFound("oct")

Step to reproduce

Create a file references.bib:

@misc{rfc6749,
    series =    {Request for Comments},
    number =    6749,
    howpublished =  {RFC 6749},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC6749},
    url =       {https://www.rfc-editor.org/info/rfc6749},
    author =    {Dick Hardt},
    title =     {{The OAuth 2.0 Authorization Framework}},
    pagetotal = 76,
    year =      2012,
    month =     oct,
    abstract =  {The OAuth 2.0 authorization framework enables a third-party application to obtain limited access to an HTTP service, either on behalf of a resource owner by orchestrating an approval interaction between the resource owner and the HTTP service, or by allowing the third-party application to obtain access on its own behalf. This specification replaces and obsoletes the OAuth 1.0 protocol described in RFC 5849. {[}STANDARDS-TRACK{]}},
}

Attempt to load the file in a template:

{% set references = load_data(path="path/to/references.bib", format="bibtex") %}

[hertg]

Just saw that you are using charlesvdv/nom-bibtex under the hood. Please let me know if I should re-open this issue over there. :)

[hertg]

Another workaround, instead of manually adjusting the bibliographies, adding the following to the top of the BibTeX file will also work:

@string (jan="1")
@string (feb="2")
@string (mar="3")
@string (apr="4")
@string (may="5")
@string (jun="6")
@string (jul="7")
@string (aug="8")
@string (sep="9")
@string (oct="10")
@string (nov="11")
@string (dec="12")

[Keats]

Upstream is definitely better

[hertg]

I opened an issue upstream: charlesvdv/nom-bibtex#26
I'll leave it up to you whether you want to close it or keep it open here. Thanks.

[Keats]

Let's close but do comment here if it gets resolved