Add strikethrough processor (#158)

* Add custom Markdown extension for strikethrough
* Simplify test matrix
* Update README
* Bump version
* Bump ruff version

Author: zerolab

.github/workflows/ruff.yml

@@ -22,6 +22,6 @@ jobs:
           python-version: "3.13"
       - name: Install dependencies
         # keep in sync with .pre-commit-config.yaml
-        run: python -Im pip install --user ruff==0.8.2
+        run: python -Im pip install --user ruff==0.13.3
       - name: Run Ruff
         run: ruff check --output-format=github ./src/wagtailmarkdown

.pre-commit-config.yaml

@@ -20,7 +20,7 @@ repos:
       - id: end-of-file-fixer
       - id: trailing-whitespace
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: 'v0.8.2'  # keep in sync with .github/workflows/ruff.yml
+    rev: 'v0.13.3'  # keep in sync with .github/workflows/ruff.yml
     hooks:
       - id: ruff
         args: [ --fix, --exit-non-zero-on-fix ]

CHANGELOG.md

@@ -1,15 +1,10 @@
 # Changelog
 
-## [Unreleased]
+## [0.13.0] - 2025-10-06
 
-- Added support and testing for Wagtail 7.1, dropped support for Wagtail 6.4 (EOL) (@damwaingames)
-
-- Add tox testing for wagtail 6.2 and 6.3 and include Django 5.1
-- Update the ruff github action which fixes the error seen in CI
-- Add tox testing for Django 5.2 and Wagtail 6.4, 7.0
-- Support only Wagtail >= 6.3
-
-- Adds support/testing for Wagtail 6.4 and 7.0, and Django 5.2. It also drops support for Wagtail 5.x and 6.2.
+- Added support Wagtail 7.1, Django 5.2 (@damwaingames)
+- Dropped support for Wagtail < 6.3
+- Added custom inline pattern for strikethrough (`~TEXT~` and `--TEXT--`) (@zerolab)
 
 ## [0.12.1] - 2024-03-09
 
@@ -19,7 +14,7 @@
 
 ### Changed
 
-- The telepath adapter code is not longer used in Wagtail 6+
+- The telepath adapter code is no longer used in Wagtail 6+
 
 ## [0.12.0] - 2024-02-29
 
@@ -137,7 +132,8 @@
 - Restructure app, refactor code. Add depreciation warnings.
 
 
-[unreleased]: https://github.com/torchbox/wagtail-markdown/compare/v0.12.1...HEAD
+[unreleased]: https://github.com/torchbox/wagtail-markdown/compare/v0.13.0...HEAD
+[0.13.0]: https://github.com/torchbox/wagtail-markdown/compare/v0.12.1...v0.13.0
 [0.12.1]: https://github.com/torchbox/wagtail-markdown/compare/v0.12.0...v0.12.1
 [0.12.0]: https://github.com/torchbox/wagtail-markdown/compare/v0.11.0...v0.12.0
 [0.11.1]: https://github.com/torchbox/wagtail-markdown/compare/v0.11.0...v0.11.1

README.md

@@ -250,6 +250,12 @@ Previously we supported custom link tags that used the target object title. They
 
 ⚠️ these types of tags are not reliable as titles can and will change. Support for  will be removed in the future.
 
+#### Inline tags
+
+wagtail-markdown supports the following custom inline tags: `~TEXT~` and `~~TEXT~~` for strikethrough. The resulting
+markup is `<del>TEXT</del>`. Note that with this, the default allowed tags include `del` and `ins`.
+
+
 ### Usage
 
 You can use it as a `StreamField` block:
@@ -347,11 +353,11 @@ tox -p
 To run tests for a specific environment:
 
 ```shell
-tox -e py313-django5.1-wagtail6.3
+tox -e py313-django5.2-wagtail7.0
 ```
 
 or, a specific test
 
 ```shell
-tox -e py313-django5.1-wagtail6.3 -- tests.testapp.tests.test_admin.TestFieldsAdmin
+tox -e py313-django5.2-wagtail7.0 -- tests.testapp.tests.test_admin.TestFieldsAdmin
 ```

src/wagtailmarkdown/__init__.py

@@ -1,2 +1,2 @@
-VERSION = (0, 12, 1)
+VERSION = (0, 13, 0)
 __version__ = ".".join(map(str, VERSION))

src/wagtailmarkdown/constants.py

@@ -34,6 +34,8 @@
     "ol",
     "hr",
     "br",
+    "del",
+    "ins",
 ]
 
 DEFAULT_ALLOWED_ATTRIBUTES = {

src/wagtailmarkdown/mdx/inlinepatterns.py

@@ -1,3 +1,5 @@
+from typing import TYPE_CHECKING, Optional
+
 from django.apps import apps
 from django.core.exceptions import MultipleObjectsReturned, ObjectDoesNotExist
 from markdown import Extension
@@ -6,13 +8,18 @@
     LINK_RE,
     ImageInlineProcessor,
     LinkInlineProcessor,
+    SimpleTagInlineProcessor,
 )
 from wagtail.documents import get_document_model
 from wagtail.images import get_image_model
 from wagtail.images.exceptions import InvalidFilterSpecError
 from wagtail.models import Page
 
 
+if TYPE_CHECKING:
+    from markdown import Markdown
+
+
 def _options_to_dict(value: str) -> dict:
     """
     Takes a "key=value,key2=value2" string and converts it to a dict
@@ -39,7 +46,7 @@ class ObjectLookupNegotiator:
     MEDIA_PREFIX = "media:"
 
     @staticmethod
-    def retrieve_page(lookup_field_value):
+    def retrieve_page(lookup_field_value) -> Optional[Page]:
         try:
             return Page.objects.get(pk=lookup_field_value)
         except (Page.DoesNotExist, Page.MultipleObjectsReturned):
@@ -131,13 +138,17 @@ def getLink(self, data, index):
 
 
 class ImageExtension(Extension):
-    def __init__(self, object_lookup_negotiator=None, **kwargs):
+    def __init__(
+        self,
+        object_lookup_negotiator: Optional[ObjectLookupNegotiator] = None,
+        **kwargs,
+    ):
         self.object_lookup_negotiator = (
             object_lookup_negotiator or ObjectLookupNegotiator
         )
         super().__init__(**kwargs)
 
-    def extendMarkdown(self, md):
+    def extendMarkdown(self, md: "Markdown") -> None:
         md.inlinePatterns.register(
             ImageProcessor(
                 pattern=IMAGE_LINK_RE,
@@ -150,13 +161,17 @@ def extendMarkdown(self, md):
 
 
 class LinkExtension(Extension):
-    def __init__(self, object_lookup_negotiator=None, **kwargs):
+    def __init__(
+        self,
+        object_lookup_negotiator: Optional[ObjectLookupNegotiator] = None,
+        **kwargs,
+    ):
         self.object_lookup_negotiator = (
             object_lookup_negotiator or ObjectLookupNegotiator
         )
         super().__init__(**kwargs)
 
-    def extendMarkdown(self, md):
+    def extendMarkdown(self, md: "Markdown") -> None:
         md.inlinePatterns.register(
             LinkProcessor(
                 pattern=LINK_RE,
@@ -166,3 +181,11 @@ def extendMarkdown(self, md):
             "link",
             161,
         )
+
+
+class DelExtension(Extension):
+    def extendMarkdown(self, md: "Markdown") -> None:
+        """Supports ~TEXT~ and ~~TEXT~~ syntax."""
+        md.inlinePatterns.register(
+            SimpleTagInlineProcessor(r"(\~{1,2})(.+?)\1", "del"), "tilde del", 170
+        )

src/wagtailmarkdown/utils.py

@@ -8,7 +8,11 @@
 from django.utils.safestring import mark_safe
 
 from wagtailmarkdown.constants import DEFAULT_BLEACH_KWARGS, SETTINGS_MODE_OVERRIDE
-from wagtailmarkdown.mdx.inlinepatterns import ImageExtension, LinkExtension
+from wagtailmarkdown.mdx.inlinepatterns import (
+    DelExtension,
+    ImageExtension,
+    LinkExtension,
+)
 from wagtailmarkdown.mdx.linker import LinkerExtension
 
 
@@ -91,6 +95,7 @@ def _get_default_markdown_kwargs():
             ),
             LinkExtension(),
             ImageExtension(),
+            DelExtension(),
         ],
         "extension_configs": {
             "codehilite": [

tests/testapp/tests/test_templatetags.py

@@ -270,3 +270,19 @@ def test_markdown_options_to_dict(self):
             _options_to_dict("class=left,filter=fill-200x200,foo =bar,baz="),
             {"class": "left", "filter": "fill-200x200", "foo": "bar", "baz": ""},
         )
+
+    def test_del_extension(self):
+        self.assertEqual(markdown("~~removed~~"), "<p><del>removed</del></p>")
+        self.assertEqual(
+            markdown("pre~~removed~~post"), "<p>pre<del>removed</del>post</p>"
+        )
+        self.assertEqual(markdown("~removed~"), "<p><del>removed</del></p>")
+        self.assertEqual(
+            markdown("pre~removed~post"), "<p>pre<del>removed</del>post</p>"
+        )
+
+        self.assertEqual(
+            markdown("~~one~~~two~~~three~~"),
+            "<p><del>one</del><del>two</del><del>three</del></p>",
+        )
+        self.assertEqual(markdown("~~~weird~~~"), "<p><del>~weird</del>~</p>")

tox.ini

@@ -2,8 +2,9 @@
 min_version = 4.22
 
 envlist =
-    py{39,310,311,312}-django42-wagtail{63,70,71}
-    py{310,311,312,313}-django{51,52}-wagtail{63,70,71}
+    py{39}-django42-wagtail{63}
+    py{310,311}-django{51}-wagtail{70}
+    py{312,313}-django{52}-wagtail{71}
 
 [gh-actions]
 python =