Prevent infinite loop when two ContextActive toggle each other

Author: houmain

src/server/ServerState.cpp

@@ -271,6 +271,7 @@ bool ServerState::flush_send_buffer() {
 
   auto succeeded = true;
   auto i = size_t{ };
+  auto toggled_virtual_keys = 0;
   for (; i < m_send_buffer.size(); ++i) {
     const auto& event = m_send_buffer[i];
 
@@ -282,8 +283,11 @@ bool ServerState::flush_send_buffer() {
     }
 
     if (is_virtual_key(event.key)) {
-      if (event.state == KeyState::Down)
-        toggle_virtual_key(event.key);
+      if (event.state == KeyState::Down) {
+        // prevent infinite loop (when two ContextActive toggle each other)
+        if (++toggled_virtual_keys < 10)
+          toggle_virtual_key(event.key);
+      }
       continue;
     }
 

src/test/test4_Server.cpp

@@ -152,7 +152,6 @@ TEST_CASE("Minimal configuration", "[Server]") {
   CHECK(state.apply_input("-A") == "-B");
 }
 
-
 //--------------------------------------------------------------------
 
 TEST_CASE("Modifier filter and no might match (infinite loop bug)", "[Server]") {
@@ -170,6 +169,41 @@ TEST_CASE("Modifier filter and no might match (infinite loop bug)", "[Server]")
 
 //--------------------------------------------------------------------
 
+TEST_CASE("Modifier filter toggled in ContextActive", "[Server]") {
+  auto state = create_state(R"(
+    X >> Virtual1
+
+    [modifier = Virtual1]
+    ContextActive >> A Virtual1
+  )");
+  CHECK(state.apply_input("+X") == "+A -A");
+  CHECK(state.apply_input("-X") == "");
+  CHECK(state.apply_input("+X") == "+A -A");
+  CHECK(state.apply_input("-X") == "");
+}
+
+//--------------------------------------------------------------------
+
+TEST_CASE("Modifier filter toggled in two ContextActive (prevent infinite loop)", "[Server]") {
+  auto state = create_state(R"(
+    C >> Virtual1
+
+    [modifier = Virtual1]
+    ContextActive >> A Virtual1
+
+    [modifier = "!Virtual1"]
+    ContextActive >> B Virtual1
+  )", false);
+  CHECK(state.set_active_contexts({ 0, 1, 2 }) == "+B -B +A -A +B -B +A -A +B -B +A -A +B -B +A -A +B -B +A -A");
+  CHECK(state.apply_input("+A -A") == "+A -A");
+  CHECK(state.apply_input("+B -B") == "+B -B");
+  CHECK(state.apply_input("+C") == "+B -B +A -A +B -B +A -A +B -B +A -A +B -B +A -A +B -B");
+  CHECK(state.apply_input("+A -A") == "+A -A");
+  CHECK(state.apply_input("+B -B") == "+B -B");
+}
+
+//--------------------------------------------------------------------
+
 TEST_CASE("Trigger Not Timeout", "[Server]") {
   auto state = create_state(R"(
     ShiftLeft{!200ms} >> B