Add support for Obsidian type blockquote alerts

* Make the alert type parsing more flexible to support more types
* Add `AlertTitle` and `AlertSign` (for folding)

Note that GitHub will not render callouts with alert title/sign.

See https://help.obsidian.md/Editing+and+formatting/Callouts

Closes #12805
Closes #12801

1 files changed, 10 insertions, 0 deletions

diff --git a/markup/converter/hooks/hooks.go b/markup/converter/hooks/hooks.go
index 96c165321..1fc513acb 100644
--- a/markup/converter/hooks/hooks.go
+++ b/markup/converter/hooks/hooks.go
@@ -109,6 +109,16 @@ type BlockquoteContext interface {
 	// The GitHub alert type converted to lowercase, e.g. "note".
 	// Only set if Type is "alert".
 	AlertType() string
+
+	// The alert title.
+	// Currently only relevant for Obsidian alerts.
+	// GitHub does not suport alert titles and will not render alerts with titles.
+	AlertTitle() hstring.HTML
+
+	// The alert sign,  "+" or "-" or "" used to indicate folding.
+	// Currently only relevant for Obsidian alerts.
+	// GitHub does not suport alert signs and will not render alerts with signs.
+	AlertSign() string
 }
 
 type PositionerSourceTargetProvider interface {