fix(js): preserve pending indicator state

Track pending class and indicator state with small reference counts so overlapping requests do not hide indicators early or strip a class that existed before the request.

req: convention/007

req: convention/008

slhx-js/runtime/slhx.js

@@ -8,6 +8,8 @@
   const pending = new WeakMap();
   const queues = new WeakMap();
   const timers = new WeakMap();
+  const pendingClassStates = new WeakMap();
+  const indicatorStates = new WeakMap();
   const disabledStates = new WeakMap();
   const sseSources = new WeakMap();
   const atomStores = new WeakMap();
@@ -71,9 +73,9 @@
 
   function showPending(el, on) {
     const klass = el.getAttribute("data-slhx-pending-class");
-    if (klass) el.classList.toggle(klass, on);
+    if (klass) togglePendingClass(el, klass, on);
     const root = rootOf(el) || document;
-    forEachElement(root, (i) => { if (i.hasAttribute("data-slhx-indicator")) i.hidden = !on; });
+    forEachElement(root, (i) => { if (i.hasAttribute("data-slhx-indicator")) toggleIndicator(i, on); });
     if (el.hasAttribute("data-slhx-disable-while-pending")) {
       const controls = [];
       if (isDisableControl(el)) controls.push(el);
@@ -82,6 +84,39 @@
     }
   }
 
+  function togglePendingClass(el, klass, on) {
+    const state = pendingClassStates.get(el);
+    if (on) {
+      if (state) state.count += 1;
+      else pendingClassStates.set(el, { count: 1, className: klass, hadClass: el.classList.contains(klass) });
+      el.classList.add(klass);
+      return;
+    }
+    if (!state) return;
+    state.count -= 1;
+    if (state.count <= 0) {
+      if (state.hadClass) el.classList.add(state.className);
+      else el.classList.remove(state.className);
+      pendingClassStates.delete(el);
+    }
+  }
+
+  function toggleIndicator(indicator, on) {
+    const state = indicatorStates.get(indicator);
+    if (on) {
+      if (state) state.count += 1;
+      else indicatorStates.set(indicator, { count: 1, hidden: indicator.hidden });
+      indicator.hidden = false;
+      return;
+    }
+    if (!state) return;
+    state.count -= 1;
+    if (state.count <= 0) {
+      indicator.hidden = state.hidden;
+      indicatorStates.delete(indicator);
+    }
+  }
+
   function toggleDisabled(control, on) {
     const state = disabledStates.get(control);
     if (on) {

slhx-js/tests/runtime.rs

@@ -55,9 +55,14 @@ fn runtime_toggles_pending_conventions_around_requests() {
 
     assert!(source.contains("function showPending(el, on)"));
     assert!(source.contains("el.getAttribute(\"data-slhx-pending-class\")"));
-    assert!(source.contains("el.classList.toggle(klass, on)"));
-    assert!(source.contains("forEachElement(root, (i) => { if (i.hasAttribute(\"data-slhx-indicator\")) i.hidden = !on; })"));
-    assert!(source.contains("i.hidden = !on"));
+    assert!(source.contains("const pendingClassStates = new WeakMap()"));
+    assert!(source.contains("function togglePendingClass(el, klass, on)"));
+    assert!(source.contains("hadClass: el.classList.contains(klass)"));
+    assert!(source.contains("if (state.hadClass) el.classList.add(state.className)"));
+    assert!(source.contains("const indicatorStates = new WeakMap()"));
+    assert!(source.contains("function toggleIndicator(indicator, on)"));
+    assert!(source.contains("toggleIndicator(i, on)"));
+    assert!(source.contains("indicator.hidden = state.hidden"));
     assert!(source.contains("el.hasAttribute(\"data-slhx-disable-while-pending\")"));
     assert!(source.contains("if (isDisableControl(el)) controls.push(el)"));
     assert!(source.contains("forEachElement(el, (child) => { if (isDisableControl(child)) controls.push(child); })"));