markdown: Migrate off deprecated extension registration interface.

Fixes #15205.

https://python-markdown.github.io/change_log/release-3.0/#homegrown-ordereddict-has-been-replaced-with-a-purpose-built-registry
https://python-markdown.github.io/change_log/release-3.0/#md_globals-keyword-deprecated-from-extension-api

The priority numbers are arbitrarily chosen to preserve the existing
order.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

zerver/lib/markdown/api_arguments_table_generator.py

@@ -21,9 +21,9 @@ class MarkdownArgumentsTableGenerator(Extension):
         for key, value in configs.items():
             self.setConfig(key, value)
 
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
-        md.preprocessors.add(
+        md.preprocessors.register(
-            'generate_api_arguments', APIArgumentsTablePreprocessor(md, self.getConfigs()), '_begin',
+            APIArgumentsTablePreprocessor(md, self.getConfigs()), 'generate_api_arguments', 505
         )
 
 

zerver/lib/markdown/api_return_values_table_generator.py

@@ -15,9 +15,9 @@ class MarkdownReturnValuesTableGenerator(Extension):
     def __init__(self, configs: Mapping[str, Any] = {}) -> None:
         self.config: Dict[str, Any] = {}
 
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
-        md.preprocessors.add(
+        md.preprocessors.register(
-            'generate_return_values', APIReturnValuesTablePreprocessor(md, self.getConfigs()), '_begin',
+            APIReturnValuesTablePreprocessor(md, self.getConfigs()), 'generate_return_values', 510
         )
 
 

zerver/lib/markdown/fenced_code.py

@@ -149,7 +149,7 @@ class FencedCodeExtension(markdown.Extension):
         for key, value in config.items():
             self.setConfig(key, value)
 
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
         """ Add FencedBlockPreprocessor to the Markdown instance. """
         md.registerExtension(self)
         processor = FencedBlockPreprocessor(

zerver/lib/markdown/help_emoticon_translations_table.py

@@ -1,5 +1,5 @@
 import re
-from typing import Any, Dict, List
+from typing import Any, List
 from typing.re import Match
 
 import markdown
@@ -36,10 +36,10 @@ ROW_HTML = """\
 """
 
 class EmoticonTranslationsHelpExtension(markdown.Extension):
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
         """ Add SettingHelpExtension to the Markdown instance. """
         md.registerExtension(self)
-        md.preprocessors.add('emoticon_translations', EmoticonTranslation(), '_end')
+        md.preprocessors.register(EmoticonTranslation(), 'emoticon_translations', -505)
 
 
 class EmoticonTranslation(Preprocessor):

zerver/lib/markdown/help_relative_links.py

@@ -1,5 +1,5 @@
 import re
-from typing import Any, Dict, List, Optional
+from typing import Any, List, Optional
 from typing.re import Match
 
 import markdown
@@ -67,10 +67,10 @@ LINK_TYPE_HANDLERS = {
 }
 
 class RelativeLinksHelpExtension(markdown.Extension):
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
         """ Add RelativeLinksHelpExtension to the Markdown instance. """
         md.registerExtension(self)
-        md.preprocessors.add('help_relative_links', RelativeLinks(), '_begin')
+        md.preprocessors.register(RelativeLinks(), 'help_relative_links', 520)
 
 relative_help_links: Optional[bool] = None
 

zerver/lib/markdown/help_settings_links.py

@@ -1,5 +1,5 @@
 import re
-from typing import Any, Dict, List, Optional
+from typing import Any, List, Optional
 from typing.re import Match
 
 import markdown
@@ -63,10 +63,10 @@ settings_markdown = """
 
 
 class SettingHelpExtension(markdown.Extension):
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
         """ Add SettingHelpExtension to the Markdown instance. """
         md.registerExtension(self)
-        md.preprocessors.add('setting', Setting(), '_begin')
+        md.preprocessors.register(Setting(), 'setting', 515)
 
 relative_settings_links: Optional[bool] = None
 

zerver/lib/markdown/include.py

@@ -1,6 +1,6 @@
 import os
 import re
-from typing import Any, Dict, List
+from typing import Any, List
 
 import markdown
 from markdown_include.include import IncludePreprocessor, MarkdownInclude
@@ -11,11 +11,11 @@ INC_SYNTAX = re.compile(r'\{!\s*(.+?)\s*!\}')
 
 
 class MarkdownIncludeCustom(MarkdownInclude):
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
-        md.preprocessors.add(
+        md.preprocessors.register(
-            'include_wrapper',
             IncludeCustomPreprocessor(md, self.getConfigs()),
-            '_begin',
+            'include_wrapper',
+            500,
         )
 
 class IncludeCustomPreprocessor(IncludePreprocessor):

zerver/lib/markdown/nested_code_blocks.py

@@ -8,11 +8,11 @@ from zerver.lib.markdown import ResultWithFamily, walk_tree_with_family
 
 
 class NestedCodeBlocksRenderer(Extension):
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
-        md.treeprocessors.add(
+        md.treeprocessors.register(
-            'nested_code_blocks',
             NestedCodeBlocksRendererTreeProcessor(md, self.getConfigs()),
-            '_end',
+            'nested_code_blocks',
+            -500,
         )
 
 class NestedCodeBlocksRendererTreeProcessor(markdown.treeprocessors.Treeprocessor):

zerver/lib/markdown/tabbed_sections.py

@@ -79,9 +79,10 @@ TAB_DISPLAY_NAMES = {
 }
 
 class TabbedSectionsGenerator(Extension):
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
-        md.preprocessors.add(
+        md.preprocessors.register(
-            'tabbed_sections', TabbedSectionsPreprocessor(md, self.getConfigs()), '_end')
+            TabbedSectionsPreprocessor(md, self.getConfigs()), 'tabbed_sections', -500
+        )
 
 class TabbedSectionsPreprocessor(Preprocessor):
     def __init__(self, md: markdown.Markdown, config: Dict[str, Any]) -> None:

zerver/openapi/markdown_extension.py

@@ -348,12 +348,12 @@ class APIMarkdownExtension(Extension):
             ],
         }
 
-    def extendMarkdown(self, md: markdown.Markdown, md_globals: Dict[str, Any]) -> None:
+    def extendMarkdown(self, md: markdown.Markdown) -> None:
-        md.preprocessors.add(
+        md.preprocessors.register(
-            'generate_code_example', APICodeExamplesPreprocessor(md, self.getConfigs()), '_begin',
+            APICodeExamplesPreprocessor(md, self.getConfigs()), 'generate_code_example', 525
         )
-        md.preprocessors.add(
+        md.preprocessors.register(
-            'generate_api_description', APIDescriptionPreprocessor(md, self.getConfigs()), '_begin',
+            APIDescriptionPreprocessor(md, self.getConfigs()), 'generate_api_description', 530
         )
 
 class APICodeExamplesPreprocessor(Preprocessor):