This looks good, I've been looking for more options for viewing test
from PDFs. A couple of comments inline in the patch:

On Mon, Dec 14, 2020 at 11:34:41AM +0800, Z572 wrote:
> diff --git a/gnu/packages/pdf.scm b/gnu/packages/pdf.scm
> index a06f351aae..817c6a27c8 100644
> --- a/gnu/packages/pdf.scm
> +++ b/gnu/packages/pdf.scm
> @@ -21,6 +21,7 @@
>  ;;; Copyright © 2020 Michael Rohleder <mike@rohleder.de>
>  ;;; Copyright © 2020 Timotej Lazar <timotej.lazar@araneo.si>
>  ;;; Copyright © 2020 Maxim Cournoyer <maxim.cournoyer@gmail.com>
> +;;; Copyright © 2020 Zheng Junjie <873216071@qq.com>
>  ;;;
>  ;;; This file is part of GNU Guix.
>  ;;;
> @@ -309,6 +310,25 @@ When present, Poppler is able to correctly render CJK and Cyrillic text.")
>  Poppler PDF rendering library.")
>      (license license:lgpl2.1+)))
>  
> +(define python-pdftotext

This should be define-public, otherwise we won't be able to find the
package. Also, this looks like you can rename it to just pdftotext, the
python part of the name doesn't look necessary to me.

> +  (package
> +    (name "python-pdftotext")
> +    (version "2.1.5")
> +    (source
> +     (origin
> +       (method url-fetch)
> +       (uri (pypi-uri "pdftotext" version))
> +       (sha256
> +        (base32
> +         "19la1cw1hmkcr8big04gm2dd5fw0y0z97g930aiy29s1gaqbiblq"))))
> +    (build-system python-build-system)
> +    (propagated-inputs
> +     `(("poppler" ,poppler)))

This shouldn't be propagated. If the output references poppler than a
regular input is fine. If it doesn't then the source should be patched
to use the package from the store.

> +    (home-page "https://github.com/jalan/pdftotext")
> +    (synopsis "Simple PDF text extraction")
> +    (description "Simple PDF text extraction")

This should be a full sentence.

> +    (license license:expat)))
> +
>  (define-public libharu
>    (package
>     (name "libharu")
> 
> 
> 

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Efraim Flashner   <efraim@flashner.co.il>   אפרים פלשנר
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