Highlighters: add an HighlighterGroup class

src/highlighters.cc

@@ -292,6 +292,33 @@ private:
     const Window& m_window;
 };
 
+void HighlighterGroup::operator()(DisplayBuffer& display_buffer)
+{
+    for (auto& highlighter : m_highlighters)
+       highlighter.second(display_buffer);
+}
+
+void HighlighterGroup::add_highlighter(HighlighterAndId&& highlighter)
+{
+    if (m_highlighters.contains(highlighter.first))
+        throw runtime_error("highlighter id not found " + highlighter.first);
+    m_highlighters.append(std::forward<HighlighterAndId>(highlighter));
+}
+
+void HighlighterGroup::remove_highlighter(const std::string& id)
+{
+    m_highlighters.remove(id);
+}
+
+HighlighterAndId HighlighterGroup::create(Window& window,
+                                          const HighlighterParameters& params)
+{
+    if (params.size() != 1)
+        throw runtime_error("wrong parameter count");
+
+    return HighlighterAndId(params[0], HighlighterGroup());
+}
+
 void register_highlighters()
 {
     HighlighterRegistry& registry = HighlighterRegistry::instance();
@@ -301,6 +328,7 @@ void register_highlighters()
     registry.register_factory("number_lines", SimpleHighlighterFactory<show_line_numbers>("number_lines"));
     registry.register_factory("hlcpp", SimpleHighlighterFactory<colorize_cplusplus>("hlcpp"));
     registry.register_factory("regex", colorize_regex_factory);
+    registry.register_factory("group", HighlighterGroup::create);
 }
 
 }

src/highlighters.hh

@@ -1,11 +1,31 @@
 #ifndef highlighters_hh_INCLUDED
 #define highlighters_hh_INCLUDED
 
+#include "highlighter.hh"
+#include "idvaluemap.hh"
+
 namespace Kakoune
 {
 
 void register_highlighters();
 
+class DisplayBuffer;
+class Window;
+
+class HighlighterGroup
+{
+public:
+    void operator()(DisplayBuffer& display_buffer);
+
+    void add_highlighter(HighlighterAndId&& highlighter);
+    void remove_highlighter(const std::string& id);
+
+    static HighlighterAndId create(Window& window,
+                                   const HighlighterParameters& params);
+private:
+    idvaluemap<std::string, HighlighterFunc> m_highlighters;
+};
+
 }
 
 #endif // highlighters_hh_INCLUDED