fix(metadata): inline parse arena allocations are lambda-free

Author: alandefreitas

src/lib/Metadata/Finalizers/DocComment/parseInlines.hpp

@@ -655,6 +655,13 @@ struct ParserState {
     // whether the next char is escaped
     bool escape_next{ false };
 
+    doc::InlineContainer*
+    make_container()
+    {
+        arena.push_back(std::make_unique<doc::InlineContainer>());
+        return arena.back().get();
+    }
+
     void
     flush_text()
     {
@@ -683,8 +690,7 @@ struct ParserState {
                 kMaxReserve);
             cur->children.reserve(desired);
         }
-        arena.push_back(std::make_unique<doc::InlineContainer>());
-        auto* scratch = arena.back().get();
+        auto* scratch = make_container();
         frames.push_back(Frame{
             r->kind,
             r,
@@ -1010,23 +1016,21 @@ parse(char const* first, char const* last, doc::InlineContainer& out_root)
         // Markdown link/image openers
         if (c == '!' && i + 1 < s.size() && s[i + 1] == '[') {
             st.flush_text();
-            st.arena.push_back(std::make_unique<doc::InlineContainer>());
             st.brackets.push_back(Bracket{
                 true,
                 st.cur,
-                st.arena.back().get()
+                st.make_container()
             });
             st.cur = st.brackets.back().label;
             i += 2;
             continue;
         }
         if (c == '[') {
             st.flush_text();
-            st.arena.push_back(std::make_unique<doc::InlineContainer>());
             st.brackets.push_back(Bracket{
                 false,
                 st.cur,
-                st.arena.back().get()
+                st.make_container()
             });
             st.cur = st.brackets.back().label;
             ++i;
@@ -1072,17 +1076,15 @@ parse(char const* first, char const* last, doc::InlineContainer& out_root)
                     } else {
                         auto href = html_get_attr(tag->attrs, "href").value_or(std::string{});
                         st.flush_text();
+                        auto* scratch = st.make_container();
                         st.frames.push_back(Frame{
                             doc::InlineKind::Link,
                             &kHtmlRule,
                             st.cur,
-                            [&]{
-                                st.arena.push_back(std::make_unique<doc::InlineContainer>());
-                                return st.arena.back().get();
-                            }(),
+                            scratch,
                             std::string{}
                         });
-                        st.cur = st.frames.back().scratch;
+                        st.cur = scratch;
                         st.frames.back().open_tok = std::move(href); // own the href bytes
                     }
                     i = tag->end;
@@ -1098,17 +1100,15 @@ parse(char const* first, char const* last, doc::InlineContainer& out_root)
                         }
                     } else {
                         st.flush_text();
+                        auto* scratch = st.make_container();
                         st.frames.push_back(Frame{
                             *kind,
                             &kHtmlRule,
                             st.cur,
-                            [&]{
-                                st.arena.push_back(std::make_unique<doc::InlineContainer>());
-                                return st.arena.back().get();
-                            }(),
+                            scratch,
                             "<tag>"
                         });
-                        st.cur = st.frames.back().scratch;
+                        st.cur = scratch;
                     }
                     i = tag->end;
                     continue;