Fix markdown character escaping bug (issue #1236)

[amidou-naba]

e.g. Fixes #0

Checklist:

• A unit test is covering the code added / modified by this PR

• In case of a new feature, docstrings have been added, with also some documentation in the docs/ folder

• A mention of the change is present in CHANGELOG.md

• This PR is ready to be merged

By submitting this pull request, I confirm that my contribution is made under the terms of the GNU LGPL 3.0 license.

[andersonhc]

Thank you for opening this PR @amidou-naba
I'll try to complete the review later today.

[amidou-naba]

Hello,
I am submitting my PR related to bug #1236, which I worked on.
This issue required updating several files and fixing parts of the code.
I also fixed some escaping characters that were not working correctly.
The effects of these fixes can be seen in merge_fragments, where the additional issues have been resolved.

Thank you for the review.

[andersonhc]

Thank you for the PR, it looks really good!
I am adding some comments on what needs to be fixed before we can merge it.

[andersonhc]

You are removing characters from the input text even when markdown=False. This portion of code should be inside an if markdown: block

[andersonhc]

I guess you missing an assert after line 200

[andersonhc]

Suggested change

	if self.MARKDOWN_ESCAPE_CHARACTER == tlt[0] and tlt[1:] in [
	"**",
	"__",
	"~~",
	"--",
	]:
	if tlt.startswith(self.MARKDOWN_ESCAPE_CHARACTER) and tlt[1:] in (
	self.MARKDOWN_BOLD_MARKER,
	self.MARKDOWN_ITALICS_MARKER,
	self.MARKDOWN_STRIKETHROUGH_MARKER,
	self.MARKDOWN_UNDERLINE_MARKER,
	):

This change would make it easier to read - less 'magic values' across the code.

[amidou-naba]

Hello, Ok no problem thank you De: "Anderson Herzogenrath da Costa" ***@***.***> À: "py-pdf/fpdf2" ***@***.***> Cc: "Amidou Nabassaga" ***@***.***>, "Mention" ***@***.***> Envoyé: Jeudi 5 Février 2026 14:31:39 Objet: Re: [py-pdf/fpdf2] Fix markdown character escaping bug (issue #1236) (PR #1741) @andersonhc requested changes on this pull request. Thank you for the PR, it looks really good! I am adding some comments on what needs to be fixed before we can merge it. In [ #1741 (comment) | fpdf/fpdf.py ] :

+ txt_frag.append(text[1])

+ txt_frag.append(text[2]) + yield frag() + text = text[3:] + continue + + if self.MARKDOWN_ESCAPE_CHARACTER == tlt[0:1] and \ + self.MARKDOWN_ESCAPE_CHARACTER == tlt[1:2]: + # double-escape, juste produce it + txt_frag.append(text[0]) + txt_frag.append(text[1]) + yield frag() + text = text[2:] + continue + + You are removing characters from the input text even when markdown=False . This portion of code should be inside an if markdown: block In [ #1741 (comment) | test/text/test_markdown_parse.py ] :

expected = (Fragment("----------", GSTATE, k=PDF.k),)

assert frags == expected frags = tuple(FPDF()._parse_chars("****BOLD**", True)) - expected = (Fragment("****BOLD", GSTATE, k=PDF.k),) + expected = (Fragment("**BOLD", GSTATE_B, k=PDF.k),) + frags = merge_fragments(tuple(FPDF()._parse_chars("\\****BOLD**\\**", True))) I guess you missing an assert after line 200 In [ #1741 (comment) | fpdf/fpdf.py ] :

+ if self.MARKDOWN_ESCAPE_CHARACTER == tlt[0] and tlt[1:] in [

+ "**", + "__", + "~~", + "--", + ]: ⬇️ Suggested change - if self.MARKDOWN_ESCAPE_CHARACTER == tlt[0] and tlt[1:] in [ - "**", - "__", - "~~", - "--", - ]: + if tlt.startswith(self.MARKDOWN_ESCAPE_CHARACTER) and tlt[1:] in ( + self.MARKDOWN_BOLD_MARKER, + self.MARKDOWN_ITALICS_MARKER, + self.MARKDOWN_STRIKETHROUGH_MARKER, + self.MARKDOWN_UNDERLINE_MARKER, + ): This change would make it easier to read - less 'magic values' across the code. — Reply to this email directly, [ #1741 (review) | view it on GitHub ] , or [ https://github.com/notifications/unsubscribe-auth/BX2ZEYH54AUZQJNMT2KJPPL4KNA3XAVCNFSM6AAAAACT6P356KVHI2DSMVQWIX3LMV43YUDVNRWFEZLROVSXG5CSMV3GSZLXHMZTONJWHE4TKMZZGU | unsubscribe ] . You are receiving this because you were mentioned. Message ID: <py-pdf/fpdf2/pull/1741/review/3756995395 @ github . com>