feat: support @n command

Author: sdkrystian

src/lib/AST/ParseJavadoc.cpp

@@ -768,6 +768,15 @@ visitInlineCommandComment(
 
     switch(unsigned ID = cmd->getID())
     {
+    // Newline
+    case CommandTraits::KCI_n:
+    {
+        if(! goodArgCount(0, *C))
+            return;
+        last_child_ = nullptr;
+        emplaceText<doc::Text>(true, "\n");
+        return;
+    }
     // Emphasis
     case CommandTraits::KCI_a:
     case CommandTraits::KCI_e:
@@ -1163,7 +1172,6 @@ visitBlockCommandComment(
     case CommandTraits::KCI_memberof:
     case CommandTraits::KCI_msc:
     case CommandTraits::KCI_mscfile:
-    case CommandTraits::KCI_n:
     case CommandTraits::KCI_name:
     case CommandTraits::KCI_namespace:
     case CommandTraits::KCI_noop:
@@ -1257,6 +1265,7 @@ visitBlockCommandComment(
     case CommandTraits::KCI_a:
     case CommandTraits::KCI_e:
     case CommandTraits::KCI_em:
+    case CommandTraits::KCI_n:
     case CommandTraits::KCI_copybrief:
     case CommandTraits::KCI_copydetails:
     case CommandTraits::KCI_copydoc:

src/lib/Gen/adoc/AdocCorpus.cpp

@@ -196,7 +196,7 @@ operator()(
     for(auto const& child : children.subspan(1))
     {
         if(non_empty)
-            dest_.push_back(' ');
+            dest_.push_back('\n');
         non_empty = write(*child, *this);
     }
     dest_.push_back('\n');
@@ -227,7 +227,7 @@ operator()(
     for(auto const& child : children.subspan(1))
     {
         if(non_empty)
-            dest_.push_back(' ');
+            dest_.push_back('\n');
         non_empty = write(*child, *this);
     }
     dest_.push_back('\n');
@@ -265,6 +265,9 @@ operator()(doc::Text const& I)
     // Asciidoc text must not have leading
     // else they can be rendered up as code.
     std::string_view s = trim(I.string);
+    // Render empty lines as paragraph delimiters.
+    if(s.empty())
+        s = "\n";
     dest_.append(escapeAdoc(s));
 }