Brought over a bunch of stuff to get started, but only lel.cpp compiles.

tests/guecs.cpp

@@ -0,0 +1,32 @@
+#include <catch2/catch_test_macros.hpp>
+#include <fmt/core.h>
+#include "constants.hpp"
+#include "guecs.hpp"
+#include "textures.hpp"
+#include <fmt/xchar.h>
+
+using namespace guecs;
+
+TEST_CASE("prototype one gui", "[ecs-gui]") {
+  guecs::UI gui;
+  textures::init();
+
+  gui.position(0, 0, 1000, 500);
+  gui.layout("[test1|test2|test3][test4|_|test5]");
+
+  for(auto& [name, cell] : gui.cells()) {
+    auto button = gui.entity(name);
+    gui.set<lel::Cell>(button, cell);
+    gui.set<Rectangle>(button, {});
+    gui.set<Clickable>(button, {});
+    gui.set<Textual>(button, {L"whatever"});
+  }
+
+  gui.init();
+
+  // at this point it's mostly ready but I'd need to render it to a window real quick
+  sf::RenderWindow window;
+  window.setSize({SCREEN_WIDTH, SCREEN_HEIGHT});
+  gui.render(window);
+  window.display();
+}

tests/lel.cpp

@@ -0,0 +1,52 @@
+#include "lel.hpp"
+#include <catch2/catch_test_macros.hpp>
+#include <fmt/core.h>
+#include <string>
+
+TEST_CASE("test basic ops", "[lel]") {
+  lel::Parser parser(0, 0, 500, 500);
+
+  bool good = parser.parse(
+     "[ label_1         | label3      | test1]"
+     "[ *(300,300)text1 | %(150)people | ^test2]"
+     "[ >label2         | _           | .test3]"
+     "[ =message        | buttons     | test4]");
+
+  REQUIRE(good);
+
+  for(size_t rowcount = 0; rowcount < parser.grid.size(); rowcount++) {
+    auto& row = parser.grid[rowcount];
+
+    for(size_t colcount = 0; colcount < row.size(); colcount++) {
+      auto &name = row[colcount];
+      if(name == "_") {
+        REQUIRE(!parser.cells.contains(name));
+      } else {
+        auto &cell = parser.cells.at(name);
+        REQUIRE(cell.row == int(rowcount));
+        REQUIRE(cell.col == int(colcount));
+      }
+    }
+  }
+
+  REQUIRE(parser.cells.size() == 11);
+  REQUIRE(parser.cells.at("label2").right == true);
+  REQUIRE(parser.cells.at("text1").expand == true);
+  REQUIRE(parser.cells.at("text1").w == 300);
+  REQUIRE(parser.cells.at("text1").h == 300);
+  REQUIRE(parser.cells.at("people").expand == false);
+  REQUIRE(parser.cells.at("message").expand == false);
+  REQUIRE(parser.cells.at("message").center == true);
+
+  for(auto& [name, cell] : parser.cells) {
+    REQUIRE(cell.w > 0);
+    REQUIRE(cell.h > 0);
+  }
+
+  auto hit = parser.hit(10, 10);
+  REQUIRE(*hit == "label_1");
+
+  auto nohit = parser.hit(1000, 1000);
+  REQUIRE(!nohit);
+  REQUIRE(nohit == std::nullopt);
+}