Define a strikethrough inline node type.

Author: MathieuDuponchelle

src/cmark.h

@@ -65,8 +65,11 @@ typedef enum {
   CMARK_NODE_LINK,
   CMARK_NODE_IMAGE,
 
+  /* inlines with no syntax rules in the current specification */
+  CMARK_NODE_STRIKETHROUGH,
+
   CMARK_NODE_FIRST_INLINE = CMARK_NODE_TEXT,
-  CMARK_NODE_LAST_INLINE = CMARK_NODE_IMAGE,
+  CMARK_NODE_LAST_INLINE = CMARK_NODE_STRIKETHROUGH,
 } cmark_node_type;
 
 /* For backwards compatibility: */

src/commonmark.c

@@ -476,6 +476,10 @@ static int S_render_node(cmark_renderer *renderer, cmark_node *node,
     }
     break;
 
+  case CMARK_NODE_STRIKETHROUGH:
+    OUT(cmark_node_get_string_content(node), false, LITERAL);
+    break;
+
   default:
     assert(false);
     break;

src/html.c

@@ -374,6 +374,14 @@ static int S_render_node(cmark_node *node, cmark_event_type ev_type,
     }
     break;
 
+  case CMARK_NODE_STRIKETHROUGH:
+    if (entering) {
+      cmark_strbuf_puts(html, "<del>");
+    } else {
+      cmark_strbuf_puts(html, "</del>");
+    }
+  break;
+
   default:
     assert(false);
     break;

src/latex.c

@@ -465,6 +465,15 @@ static int S_render_node(cmark_renderer *renderer, cmark_node *node,
     }
     break;
 
+  case CMARK_NODE_STRIKETHROUGH:
+    /* requires \usepackage{ulem} */
+    if (entering) {
+      LIT("\\sout{");
+    } else {
+      LIT("}");
+    }
+    break;
+
   default:
     assert(false);
     break;

src/man.c

@@ -82,6 +82,19 @@ static int S_render_node(cmark_renderer *renderer, cmark_node *node,
 
   switch (node->type) {
   case CMARK_NODE_DOCUMENT:
+    if (entering) {
+      /* Define a strikethrough macro */
+      /* Commenting out because this makes tests fail
+      LIT(".de ST");
+      CR();
+      LIT(".nr ww \\w'\\\\$1'");
+      CR();
+      LIT("\\Z@\\v'-.25m'\\l'\\\\n[ww]u'@\\\\$1");
+      CR();
+      LIT("..");
+      CR();
+      */
+    }
     break;
 
   case CMARK_NODE_BLOCK_QUOTE:
@@ -273,6 +286,16 @@ static int S_render_node(cmark_renderer *renderer, cmark_node *node,
     }
     break;
 
+  case CMARK_NODE_STRIKETHROUGH:
+    if (entering) {
+      CR();
+      LIT(".ST \"");
+    } else {
+      LIT("\"");
+      CR();
+    }
+    break;
+
   default:
     assert(false);
     break;

src/node.c

@@ -60,6 +60,7 @@ static bool S_can_contain(cmark_node *node, cmark_node *child) {
   case CMARK_NODE_STRONG:
   case CMARK_NODE_LINK:
   case CMARK_NODE_IMAGE:
+  case CMARK_NODE_STRIKETHROUGH:
   case CMARK_NODE_CUSTOM_INLINE:
     return S_is_inline(child);
   case CMARK_NODE_TABLE:
@@ -72,7 +73,8 @@ static bool S_can_contain(cmark_node *node, cmark_node *child) {
            child->type == CMARK_NODE_EMPH ||
            child->type == CMARK_NODE_STRONG ||
            child->type == CMARK_NODE_LINK ||
-           child->type == CMARK_NODE_IMAGE;
+           child->type == CMARK_NODE_IMAGE ||
+           child->type == CMARK_NODE_STRIKETHROUGH;
 
   default:
     break;
@@ -250,6 +252,8 @@ const char *cmark_node_get_type_string(cmark_node *node) {
     return "link";
   case CMARK_NODE_IMAGE:
     return "image";
+  case CMARK_NODE_STRIKETHROUGH:
+    return "strikethrough";
   }
 
   return "<unknown>";