HS: on-suite parser fixes (+5 tests)

- parse-halt-cmd: after consuming 'the event's', check for 'bubbling'
  token and return "bubbling" mode instead of "the-event"
- parse-wait-cmd: skip article words (a/an/the) before reading event
  name, so 'wait for a customEvent' works correctly
- parse-on-feat: parse optional (vars) paren group before flt and
  consume-having!, so 'on intersection(intersecting) having ...' works;
  inject event-var refs into body for compiler's event-refs mechanism

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/hyperscript/parser.sx

@@ -1573,7 +1573,7 @@
           (cond
             ((match-kw "for")
               (let
-                ((event-name (tp-val)))
+                ((event-name (do (when (or (= (tp-val) "a") (= (tp-val) "an") (= (tp-val) "the")) (adv!)) (tp-val))))
                 (adv!)
                 (let
                   ((destructure (if (= (tp-type) "paren-open") (let ((_ (adv!))) (define collect-dnames (fn (acc) (cond ((or (= (tp-type) "paren-close") (at-end?)) (do (if (= (tp-type) "paren-close") (adv!) nil) acc)) ((= (tp-type) "comma") (do (adv!) (collect-dnames acc))) (true (let ((name (tp-val))) (adv!) (collect-dnames (append acc (list name)))))))) (collect-dnames (list))) nil)))
@@ -2428,7 +2428,7 @@
         (fn
           ()
           (let
-            ((mode (cond ((match-kw "the") (do (match-kw "event") (when (and (= (tp-type) "op") (= (tp-val) "'s")) (adv!)) "the-event")) ((or (match-kw "default") (and (= (tp-val) "default") (do (adv!) true))) "default") ((or (match-kw "bubbling") (and (= (tp-val) "bubbling") (do (adv!) true))) "bubbling") (true "all"))))
+            ((mode (cond ((match-kw "the") (do (match-kw "event") (when (and (= (tp-type) "op") (= (tp-val) "'s")) (adv!)) (if (= (tp-val) "bubbling") (do (adv!) "bubbling") "the-event"))) ((or (match-kw "default") (and (= (tp-val) "default") (do (adv!) true))) "default") ((or (match-kw "bubbling") (and (= (tp-val) "bubbling") (do (adv!) true))) "bubbling") (true "all"))))
             (list (quote halt!) mode))))
       (define
         parse-param-list
@@ -2917,6 +2917,8 @@
                 ((count-filter (let ((mn nil) (mx nil)) (when first? (do (set! mn 1) (set! mx 1))) (when (= (tp-type) "number") (let ((n (parse-number (tp-val)))) (do (adv!) (set! mn n) (cond ((match-kw "to") (cond ((= (tp-type) "number") (let ((mv (parse-number (tp-val)))) (do (adv!) (set! mx mv)))) (true (set! mx n)))) ((match-kw "and") (cond ((match-kw "on") (set! mx -1)) (true (set! mx n)))) (true (set! mx n)))))) (if mn (dict "min" mn "max" mx) nil))))
                 (let
                   ((of-filter (when (and (= event-name "mutation") (match-kw "of")) (cond ((and (= (tp-type) "ident") (or (= (tp-val) "attributes") (= (tp-val) "childList") (= (tp-val) "characterData"))) (let ((nm (tp-val))) (do (adv!) (dict "type" nm)))) ((= (tp-type) "attr") (let ((attrs (list (tp-val)))) (do (adv!) (define collect-or! (fn () (when (match-kw "or") (cond ((= (tp-type) "attr") (do (set! attrs (append attrs (list (tp-val)))) (adv!) (collect-or!))) (true (set! p (- p 1))))))) (collect-or!) (dict "type" "attrs" "attrs" attrs)))) (true nil)))))
+                  (let
+                    ((event-vars (if (= (tp-type) "paren-open") (do (adv!) (define ev-coll (fn () (cond ((or (= (tp-type) "paren-close") (= (tp-type) "eof")) (do (when (= (tp-type) "paren-close") (adv!)) (list))) ((or (= (tp-type) "ident") (= (tp-type) "keyword")) (let ((nm (tp-val))) (adv!) (cons nm (ev-coll)))) (true (do (adv!) (ev-coll)))))) (ev-coll)) (list))))
                     (let
                       ((flt (if (= (tp-type) "bracket-open") (do (adv!) (let ((f (parse-expr))) (if (= (tp-type) "bracket-close") (adv!) nil) f)) nil)))
                       (let
@@ -2984,8 +2986,8 @@
                                                   (let
                                                     ((parts (if finally-clause (append parts (list :finally finally-clause)) parts)))
                                                     (let
-                                                    ((parts (append parts (list body))))
+                                                      ((parts (append parts (list (if (> (len event-vars) 0) (cons (quote do) (append (map (fn (nm) (list (quote ref) nm)) event-vars) (if (and (list? body) (= (first body) (quote do))) (rest body) (list body)))) body)))))
-                                                    parts)))))))))))))))))))))))
+                                                      parts))))))))))))))))))))))))
       (define
         parse-init-feat
         (fn

shared/static/wasm/sx/hs-parser.sx

@@ -1573,7 +1573,7 @@
           (cond
             ((match-kw "for")
               (let
-                ((event-name (tp-val)))
+                ((event-name (do (when (or (= (tp-val) "a") (= (tp-val) "an") (= (tp-val) "the")) (adv!)) (tp-val))))
                 (adv!)
                 (let
                   ((destructure (if (= (tp-type) "paren-open") (let ((_ (adv!))) (define collect-dnames (fn (acc) (cond ((or (= (tp-type) "paren-close") (at-end?)) (do (if (= (tp-type) "paren-close") (adv!) nil) acc)) ((= (tp-type) "comma") (do (adv!) (collect-dnames acc))) (true (let ((name (tp-val))) (adv!) (collect-dnames (append acc (list name)))))))) (collect-dnames (list))) nil)))
@@ -2428,7 +2428,7 @@
         (fn
           ()
           (let
-            ((mode (cond ((match-kw "the") (do (match-kw "event") (when (and (= (tp-type) "op") (= (tp-val) "'s")) (adv!)) "the-event")) ((or (match-kw "default") (and (= (tp-val) "default") (do (adv!) true))) "default") ((or (match-kw "bubbling") (and (= (tp-val) "bubbling") (do (adv!) true))) "bubbling") (true "all"))))
+            ((mode (cond ((match-kw "the") (do (match-kw "event") (when (and (= (tp-type) "op") (= (tp-val) "'s")) (adv!)) (if (= (tp-val) "bubbling") (do (adv!) "bubbling") "the-event"))) ((or (match-kw "default") (and (= (tp-val) "default") (do (adv!) true))) "default") ((or (match-kw "bubbling") (and (= (tp-val) "bubbling") (do (adv!) true))) "bubbling") (true "all"))))
             (list (quote halt!) mode))))
       (define
         parse-param-list
@@ -2917,6 +2917,8 @@
                 ((count-filter (let ((mn nil) (mx nil)) (when first? (do (set! mn 1) (set! mx 1))) (when (= (tp-type) "number") (let ((n (parse-number (tp-val)))) (do (adv!) (set! mn n) (cond ((match-kw "to") (cond ((= (tp-type) "number") (let ((mv (parse-number (tp-val)))) (do (adv!) (set! mx mv)))) (true (set! mx n)))) ((match-kw "and") (cond ((match-kw "on") (set! mx -1)) (true (set! mx n)))) (true (set! mx n)))))) (if mn (dict "min" mn "max" mx) nil))))
                 (let
                   ((of-filter (when (and (= event-name "mutation") (match-kw "of")) (cond ((and (= (tp-type) "ident") (or (= (tp-val) "attributes") (= (tp-val) "childList") (= (tp-val) "characterData"))) (let ((nm (tp-val))) (do (adv!) (dict "type" nm)))) ((= (tp-type) "attr") (let ((attrs (list (tp-val)))) (do (adv!) (define collect-or! (fn () (when (match-kw "or") (cond ((= (tp-type) "attr") (do (set! attrs (append attrs (list (tp-val)))) (adv!) (collect-or!))) (true (set! p (- p 1))))))) (collect-or!) (dict "type" "attrs" "attrs" attrs)))) (true nil)))))
+                  (let
+                    ((event-vars (if (= (tp-type) "paren-open") (do (adv!) (define ev-coll (fn () (cond ((or (= (tp-type) "paren-close") (= (tp-type) "eof")) (do (when (= (tp-type) "paren-close") (adv!)) (list))) ((or (= (tp-type) "ident") (= (tp-type) "keyword")) (let ((nm (tp-val))) (adv!) (cons nm (ev-coll)))) (true (do (adv!) (ev-coll)))))) (ev-coll)) (list))))
                     (let
                       ((flt (if (= (tp-type) "bracket-open") (do (adv!) (let ((f (parse-expr))) (if (= (tp-type) "bracket-close") (adv!) nil) f)) nil)))
                       (let
@@ -2984,8 +2986,8 @@
                                                   (let
                                                     ((parts (if finally-clause (append parts (list :finally finally-clause)) parts)))
                                                     (let
-                                                    ((parts (append parts (list body))))
+                                                      ((parts (append parts (list (if (> (len event-vars) 0) (cons (quote do) (append (map (fn (nm) (list (quote ref) nm)) event-vars) (if (and (list? body) (= (first body) (quote do))) (rest body) (list body)))) body)))))
-                                                    parts)))))))))))))))))))))))
+                                                      parts))))))))))))))))))))))))
       (define
         parse-init-feat
         (fn