HS: wait on event basics (+4 tests)

Five parts: (a) tests/hs-run-filtered.js `io-wait-event` mock now
registers a one-shot listener on the target element and resumes with
the event, instead of immediately resuming with nil. (b) Added
hs-wait-for-or runtime form carrying a timeout-ms; mock resumes
immediately when a timeout is present (0ms tests). (c) parser
parse-wait-cmd recognises `wait for EV(v1, v2)` destructure syntax,
emits :destructure list on wait-for AST. (d) compiler emit-wait-for
updated for :from/:or combos; a new `__bind-from-detail__` form
compiles to `(define v (host-get (host-get it "detail") v))`, and the
`do`-sequence handler preprocesses wait-for to splice these synthetic
bindings after the wait. (e) generator extracts `detail: ...` from
`CustomEvent` options so dispatched events carry their payload.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/hs-run-filtered.js

@@ -341,7 +341,23 @@ globalThis._driveAsync=function driveAsync(r,d){d=d||0;if(d>500||!r||!r.suspende
   else if(opName==='io-parse-json'){const resp=items&&items[1];try{doResume(JSON.parse(typeof resp==='string'?resp:resp&&resp._json?resp._json:'{}'));}catch(e){doResume(null);}}
   else if(opName==='io-parse-html'){const frag=new El('fragment');frag.nodeType=11;doResume(frag);}
   else if(opName==='io-settle')doResume(null);
-  else if(opName==='io-wait-event')doResume(null);
+  else if(opName==='io-wait-event'){
+    const target=items&&items[1];
+    const evName=typeof items[2]==='string'?items[2]:'';
+    const timeout=items&&items.length>3?items[3]:undefined;
+    if(typeof timeout==='number'){
+      // `wait for EV or Nms` — timeout wins immediately in the mock (tests use 0ms)
+      doResume(null);
+    } else if(target && target instanceof El && evName){
+      const handler=function(ev){
+        target.removeEventListener(evName,handler);
+        doResume(ev);
+      };
+      target.addEventListener(evName,handler);
+    } else {
+      doResume(null);
+    }
+  }
   else if(opName==='io-transition')doResume(null);
 };
 

tests/playwright/generate-sx-tests.py

@@ -783,6 +783,25 @@ def _window_setup_ops(assign_body):
     return out
 
 
+def _extract_detail_expr(opts_src):
+    """Extract `detail: ...` from an event options block like `, { detail: X }`.
+    Returns an SX expression string, defaulting to `nil`."""
+    if not opts_src:
+        return 'nil'
+    # Plain string detail
+    dm = re.search(r'detail:\s*"([^"]*)"', opts_src)
+    if dm:
+        return f'"{dm.group(1)}"'
+    # Simple object detail: { k: "v", k2: "v2", ... } (string values only)
+    dm = re.search(r'detail:\s*\{([^{}]*)\}', opts_src)
+    if dm:
+        pairs = re.findall(r'(\w+):\s*"([^"]*)"', dm.group(1))
+        if pairs:
+            items = ' '.join(f':{k} "{v}"' for k, v in pairs)
+            return '{' + items + '}'
+    return 'nil'
+
+
 def parse_dev_body(body, elements, var_names):
     """Parse Playwright test body into ordered SX ops.
 
@@ -950,13 +969,15 @@ def parse_dev_body(body, elements, var_names):
         m = re.match(
             r"evaluate\(\s*\(\)\s*=>\s*document\.querySelector\(\s*(['\"])([^'\"]+)\1\s*\)"
             r"\.dispatchEvent\(\s*new\s+(?:Custom)?Event\(\s*(['\"])([^'\"]+)\3"
-            r"(?:\s*,\s*[^)]*)?\s*\)\s*\)\s*\)\s*$",
+            r"(\s*,\s*\{.*\})?\s*\)\s*\)\s*\)\s*$",
             stmt_na, re.DOTALL,
         )
         if m and seen_html:
             sel = re.sub(r'^#work-area\s+', '', m.group(2))
             target = selector_to_sx(sel, elements, var_names)
-            ops.append(f'(dom-dispatch {target} "{m.group(4)}" nil)')
+            opts = m.group(5) or ''
+            detail_expr = _extract_detail_expr(opts)
+            ops.append(f'(dom-dispatch {target} "{m.group(4)}" {detail_expr})')
             continue
 
         # evaluate(() => { const e = new Event(NAME, {...}); document.querySelector(SEL).dispatchEvent(e); })
@@ -964,15 +985,17 @@ def parse_dev_body(body, elements, var_names):
         m = re.match(
             r"evaluate\(\s*\(\)\s*=>\s*\{\s*"
             r"const\s+(\w+)\s*=\s*new\s+(?:Custom)?Event\(\s*(['\"])([^'\"]+)\2"
-            r"(?:\s*,\s*\{[^}]*\})?\s*\)\s*;\s*"
-            r"document\.querySelector\(\s*(['\"])([^'\"]+)\4\s*\)"
+            r"(\s*,\s*\{[^}]*\})?\s*\)\s*;\s*"
+            r"document\.querySelector\(\s*(['\"])([^'\"]+)\5\s*\)"
             r"\.dispatchEvent\(\s*\1\s*\)\s*;?\s*\}\s*\)\s*$",
             stmt_na, re.DOTALL,
         )
         if m and seen_html:
-            sel = re.sub(r'^#work-area\s+', '', m.group(5))
+            sel = re.sub(r'^#work-area\s+', '', m.group(6))
             target = selector_to_sx(sel, elements, var_names)
-            ops.append(f'(dom-dispatch {target} "{m.group(3)}" nil)')
+            opts = m.group(4) or ''
+            detail_expr = _extract_detail_expr(opts)
+            ops.append(f'(dom-dispatch {target} "{m.group(3)}" {detail_expr})')
             continue
 
         # evaluate(() => document.getElementById(ID).METHOD()) — generic