bar: Make module separator a label

Some people use text modules instead of the `separator` key in the bar
section to better configure the separator (colors, fonts).
Since we disallowed the same module being used multiple times in #1534,
this will now print an error message.

This should help with this a bit.

Ref #1913

include/components/builder.hpp

@@ -10,10 +10,6 @@ POLYBAR_NS
 using std::map;
 
 // fwd decl
-namespace drawtypes {
-  class label;
-  using label_t = shared_ptr<label>;
-}  // namespace drawtypes
 using namespace drawtypes;
 
 class builder {

include/components/types.hpp

@@ -12,6 +12,12 @@ POLYBAR_NS
 // fwd {{{
 struct randr_output;
 using monitor_t = shared_ptr<randr_output>;
+
+namespace drawtypes {
+  class label;
+}
+
+using label_t = shared_ptr<drawtypes::label>;
 // }}}
 
 struct enum_hash {
@@ -159,7 +165,7 @@ struct bar_settings {
 
   struct radius radius {};
   int spacing{0};
-  string separator{};
+  label_t separator{};
 
   string wmname{};
   string locale{};

include/drawtypes/label.hpp

@@ -18,9 +18,6 @@ namespace drawtypes {
     bool zpad{false};
   };
 
-  class label;
-  using label_t = shared_ptr<label>;
-
   class label : public non_copyable_mixin<label> {
    public:
     string m_foreground{};

include/drawtypes/progressbar.hpp

@@ -9,10 +9,6 @@
 POLYBAR_NS
 
 namespace drawtypes {
-  // fwd
-  class label;
-  using label_t = shared_ptr<label>;
-
   class progressbar : public non_copyable_mixin<progressbar> {
    public:
     explicit progressbar(const bar_settings& bar, int width, string format);

include/modules/meta/base.hpp

@@ -29,8 +29,6 @@ using std::map;
 // fwd decl {{{
 
 namespace drawtypes {
-  class label;
-  using label_t = shared_ptr<label>;
   class ramp;
   using ramp_t = shared_ptr<ramp>;
   class progressbar;

src/components/bar.cpp

@@ -7,6 +7,7 @@
 #include "components/screen.hpp"
 #include "components/taskqueue.hpp"
 #include "components/types.hpp"
+#include "drawtypes/label.hpp"
 #include "events/signal.hpp"
 #include "events/signal_emitter.hpp"
 #include "utils/bspwm.hpp"
@@ -155,7 +156,7 @@ bar::bar(connection& conn, signal_emitter& emitter, const config& config, const
   // Load configuration values
   m_opts.origin = m_conf.get(bs, "bottom", false) ? edge::BOTTOM : edge::TOP;
   m_opts.spacing = m_conf.get(bs, "spacing", m_opts.spacing);
-  m_opts.separator = m_conf.get(bs, "separator", ""s);
+  m_opts.separator = drawtypes::load_optional_label(m_conf, bs, "separator", "");
   m_opts.locale = m_conf.get(bs, "locale", ""s);
 
   auto radius = m_conf.get<double>(bs, "radius", 0.0);

src/components/controller.cpp

@@ -3,6 +3,7 @@
 #include <csignal>
 
 #include "components/bar.hpp"
+#include "components/builder.hpp"
 #include "components/config.hpp"
 #include "components/ipc.hpp"
 #include "components/logger.hpp"
@@ -447,12 +448,15 @@ void controller::process_inputdata() {
 bool controller::process_update(bool force) {
   const bar_settings& bar{m_bar->settings()};
   string contents;
-  string separator{bar.separator};
   string padding_left(bar.padding.left, ' ');
   string padding_right(bar.padding.right, ' ');
   string margin_left(bar.module_margin.left, ' ');
   string margin_right(bar.module_margin.right, ' ');
 
+  builder build{bar};
+  build.node(bar.separator);
+  string separator{build.flush()};
+
   for (const auto& block : m_blocks) {
     string block_contents;
     bool is_left = false;