I am interested to change the font of some text that is in documents.

I used the #581-filtering-by-font example and added re-submitting to SimpleFindReplace and it is triggering the assertion that a rectangle cannot have a negative width.

I have confirmed the initial font 'VFMBOX+HelveticaNeueLTStd-Roman' is in the document.

Borb version 2.1.25

Python version - 3.11

This is the code -

*`#!chapter_005/src/snippet_017.py
import typing

from borb.pdf import Document
from borb.pdf import PDF
from borb.toolkit import FontNameFilter
from borb.toolkit import SimpleTextExtraction
from borb.toolkit import SimpleFindReplace

def main():

    # create FontNameFilter
    l0: FontNameFilter = FontNameFilter("VFMBOX+HelveticaNeueLTStd-Roman")

    # filtered text just gets passed to SimpleTextExtraction
    l1: SimpleTextExtraction = SimpleTextExtraction()
    l0.add_listener(l1)

    # read the Document
    doc: typing.Optional[Document] = None
    with open("C:\Data\PDFFontChange\PD-1239-G_RevA_PR.pdf", "rb") as in_file_handle:
        doc = PDF.loads(in_file_handle, [l0])

    # check whether we have read a Document
    assert doc is not None

    templist = (l1.get_text()[0]).splitlines()
    # print(templist)
    i = 0 
    for x in templist :
        print(i, ' : ', x)
        i += 1
        doc = SimpleFindReplace.sub(x, x, doc, repl_font="Helvetica")

    # store
    with open("output2.pdf", "wb") as pdf_file_handle:
        PDF.dumps(pdf_file_handle, doc)

if __name__ == "__main__":
    main()

Here is the full error traceback & I have included the first numbered (printed as 0 : ) text found by the FontNameFilter from the PDF that is resubmitted by the code into the SimpleFindReplace that triggers the error.

0  :  At the heart of your pump or dispenser,
Traceback (most recent call last):
  File "c:\Python\Glenn_Begin\PDF_Workings\BORB_PDF_FontNameAlterTrajan.py", line 43, in <module>
    main()
  File "c:\Python\Glenn_Begin\PDF_Workings\BORB_PDF_FontNameAlterTrajan.py", line 36, in main
    doc = SimpleFindReplace.sub(x, x, doc, repl_font="Helvetica")
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\toolkit\text\simple_find_replace.py", line 72, in sub
    ] = RegularExpressionTextExtraction.get_matches_for_pdf(pattern, doc)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\toolkit\text\regular_expression_text_extraction.py", line 375, in get_matches_for_pdf
    CanvasStreamProcessor(page, Canvas(), []).read(page_source, [cse])
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\pdf\canvas\canvas_stream_processor.py", line 277, in read
    raise e
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\pdf\canvas\canvas_stream_processor.py", line 271, in read
    operator.invoke(self, operands, event_listeners)
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\pdf\canvas\operator\text\show_text_with_glyph_positioning.py", line 84, in invoke
    l._event_occurred(tri)
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\toolkit\text\regular_expression_text_extraction.py", line 326, in _event_occurred
    self._render_text(event)
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\toolkit\text\regular_expression_text_extraction.py", line 338, in _render_text
    for e in text_render_info.split_on_glyphs():
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\pdf\canvas\event\chunk_of_text_render_event.py", line 177, in split_on_glyphs
    e._baseline_bounding_box = Rectangle(
                               ^^^^^^^^^^
  File "C:\Python\Glenn_Begin\.venv\Lib\site-packages\borb\pdf\canvas\geometry\rectangle.py", line 30, in __init__
    assert width >= 0, "A Rectangle must have a non-negative width."
           ^^^^^^^^^^
AssertionError: A Rectangle must have a non-negative width.