The UI is _finally_ responsive while the builder runs.

Makefile

@@ -16,7 +16,7 @@ test:
 	meson test -C builddir --suite turings_tarpit
 
 # make an install for real maybe copy dll and .exe to dir and zip?
-install: build test
+install: build
 	powershell "cp ./builddir/subprojects/libgit2-1.8.1/liblibgit2package.dll ."
 	powershell "cp ./builddir/subprojects/efsw/libefsw.dll ."
 	powershell "cp builddir/escape_turings_tarpit.exe ."

builder.cpp

@@ -120,27 +120,45 @@ void Builder::waiting(BuildEvent ev) {
     game.start_round();
     gui.building();
     gui.output(format("CHANGES! Running build {}", build_cmd));
-    build_fut = std::async([&]() {
-        return start_command(build_cmd);
-    });
-    state(STARTING);
+    state(FORKING);
   }
 }
 
-void Builder::starting(BuildEvent ev) {
+void Builder::forking(BuildEvent ev) {
+  if(build_fut.valid()) {
     std::future_status status = build_fut.wait_for(0ms);
 
     if(status == std::future_status::ready) {
       build_out = build_fut.get();
       state(READING);
     } else {
-    state(STARTING);
+      state(FORKING);
+    }
+  } else {
+    build_fut = std::async([&]() {
+        return start_command(build_cmd);
+    });
+
+    state(FORKING);
   }
 }
 
 void Builder::reading(BuildEvent ev) {
-  line = read_line(build_out, build_done);
+  // BUG: too much copy-pasta so turn this into a class?
+  if(read_fut.valid()) {
+    std::future_status status = read_fut.wait_for(0ms);
+
+    if(status == std::future_status::ready) {
+      line = read_fut.get();
       state(BUILDING);
+    } else {
+      state(READING);
+    }
+  } else {
+    read_fut = std::async([&]() {
+        return read_line(build_out, build_done);
+    });
+  }
 }
 
 void Builder::done(BuildEvent ev) {

builder.hpp

@@ -20,7 +20,7 @@ struct MatchResult {
 };
 
 enum BuildState {
-  START, WAITING, BUILDING, DONE, STARTING, READING,
+  START, WAITING, BUILDING, DONE, FORKING, READING,
   EXIT, ERROR
 };
 
@@ -41,6 +41,7 @@ class Builder : DeadSimpleFSM<BuildState, BuildEvent> {
   bool build_done = false;
   string line = "";
   std::future<FILE *> build_fut;
+  std::future<string> read_fut;
   git_repository* repo = nullptr;
 
   public:
@@ -60,7 +61,7 @@ class Builder : DeadSimpleFSM<BuildState, BuildEvent> {
         FSM_STATE(START, start, ev);
         FSM_STATE(WAITING, waiting, ev);
         FSM_STATE(DONE, done, ev);
-        FSM_STATE(STARTING, starting, ev);
+        FSM_STATE(FORKING, forking, ev);
         FSM_STATE(READING, reading, ev);
         FSM_STATE(EXIT, exit, ev);
         FSM_STATE(ERROR, exit, ev);
@@ -74,7 +75,7 @@ class Builder : DeadSimpleFSM<BuildState, BuildEvent> {
   void start(BuildEvent ev);
   void waiting(BuildEvent ev);
   void done(BuildEvent ev);
-  void starting(BuildEvent ev);
+  void forking(BuildEvent ev);
   void reading(BuildEvent ev);
   void error(BuildEvent ev);
   void exit(BuildEvent ev);

game_engine.hpp

@@ -40,22 +40,3 @@ class GameEngine {
 
   void reset();
 };
-
-class Brainfucker {
-
-  public:
-  size_t dp = 0;
-  size_t ip = 0;
-  std::stringstream out;
-  std::array<int, 100> data = {};
-  string code = {};
-
-  Brainfucker();
-
-  void run(int count);
-  void set_code(string &code);
-  void reset();
-  void jump_backward();
-  void jump_forward();
-  string to_string();
-};