HS-gen: string-aware line-comment stripping (+1 test)

process_hs_val stripped `//…` line comments with a naïve regex,
which devoured `https://yyy.xxxxxx.com/…` inside a backtick template
— the 'properly interpolates values 2' fixture was landing with
the HS source truncated at `https:`.

New helper _strip_hs_line_comments walks char-by-char and only
strips `//` / leading-whitespace `--` when not inside `'…'`, `"…"`,
or backticks; respects `\\`-escapes inside strings.

Suite hs-upstream-core/regressions: 11/16 → 12/16.
Smoke 0-195: 163/195 → 164/195.

plans/hs-conformance-scoreboard.md

@@ -4,10 +4,10 @@ Live tally for `plans/hs-conformance-to-100.md`. Update after every cluster comm
 
 ```
 Baseline:   1213/1496 (81.1%)
-Merged:     1248/1496 (83.4%)   delta +35
+Merged:     1249/1496 (83.5%)   delta +36
 Worktree:   all merged
 Target:     1496/1496 (100.0%)
-Remaining:  ~248 tests
+Remaining:  ~247 tests
 ```
 
 ## Cluster ledger
@@ -44,7 +44,7 @@ Remaining:  ~248 tests
 | 21 | `possessiveExpression` property access via its | done | +1 | f0c41278 |
 | 22 | window global fn fallback | blocked | — | — |
 | 23 | `me symbol works in from expressions` | done | +1 | 0d38a75b |
-| 24 | `properly interpolates values 2` | pending | (+1 est) | — |
+| 24 | `properly interpolates values 2` | done | +1 | (pending) |
 | 25 | parenthesized commands and features | pending | (+1 est) | — |
 
 ### Bucket C — feature stubs (observer mocks)
@@ -86,7 +86,7 @@ Defer until A–D drain. Estimated ~25 recoverable tests.
 | Bucket | Done | Partial | In-prog | Pending | Blocked | Design-done | Total |
 |--------|-----:|--------:|--------:|--------:|--------:|------------:|------:|
 | A      | 12   | 4       | 0       | 0       | 1       | —           | 17    |
-| B      | 2    | 0       | 0       | 4       | 1       | —           | 7     |
+| B      | 3    | 0       | 0       | 3       | 1       | —           | 7     |
 | C      | 0    | 0       | 0       | 5       | 0       | —           | 5     |
 | D      | 0    | 0       | 0       | 5       | 0       | —           | 5     |
 | E      | 0    | 0       | 0       | 0       | 0       | 5           | 5     |

plans/hs-conformance-to-100.md

@@ -82,7 +82,7 @@ Each cluster below is one commit. Order is rough — a loop agent may skip ahead
 
 23. **[done (+1)] `me symbol works in from expressions`** — `regressions` (1 test, Expected `Foo`). Check `from` expression compilation. Expected: +1.
 
-24. **[pending] `properly interpolates values 2`** — URL interpolation regression (1 test). Likely template string + property access. Expected: +1.
+24. **[done (+1)] `properly interpolates values 2`** — URL interpolation regression (1 test). Likely template string + property access. Expected: +1.
 
 25. **[pending] `can support parenthesized commands and features`** — `parser` (1 test, Expected `clicked`). Parser needs to accept `(cmd...)` grouping in more contexts. Expected: +1.
 
@@ -162,6 +162,9 @@ Many tests are `SKIP (untranslated)` because `tests/playwright/generate-sx-tests
 
 (Reverse chronological — newest at top.)
 
+### 2026-04-24 — cluster 24 properly interpolates values 2
+- **COMMIT** — `HS-gen: string-aware line-comment stripping (+1 test)`. `process_hs_val` in `tests/playwright/generate-sx-tests.py` stripped `//…` line comments with a naïve regex, which devoured `https://yyy.xxxxxx.com/…` inside a backtick template — test 2074 was landing with the HS source truncated at `https:`. New helper `_strip_hs_line_comments` walks char-by-char and only strips `//` / leading-whitespace `--` when not inside `'…'`, `"…"`, or `` `…` ``; also respects `\\`-escapes inside strings. Regen produced full template intact. Suite hs-upstream-core/regressions: 11/16 → 12/16. Smoke 0-195: 163/195 → 164/195.
+
 ### 2026-04-24 — cluster 23 me symbol works in from expressions
 - **0d38a75b** — `HS: closest parent <sel> traversal (+1 test)`. `parse-trav` now recognises `parent` as an ident modifier after the `closest` keyword: consumes it and re-invokes itself with kind `closest-parent`, so `closest parent <div/>` produces AST `(closest-parent "div" (me))` instead of `(string-postfix (closest "*" (me)) "parent")` — the latter was the generic trailing-ident-as-unit rule swallowing `parent`. Compiler translates `(closest-parent sel target)` to `(dom-closest (host-get target "parentElement") sel)` so `me` (the element with the `_` attribute) is skipped and only strict ancestors match. Also added `closest-parent` to the `put X into <trav>` inner-html shortcut alongside `next`/`previous`/`closest`. Suite hs-upstream-core/regressions: 10/16 → 11/16. Smoke 0-195: 162/195 → 163/195.
 

spec/tests/test-hyperscript-behavioral.sx

@@ -2070,7 +2070,7 @@
   (deftest "properly interpolates values 2"
     (hs-cleanup!)
     (let ((_el-button (dom-create-element "button")))
-      (dom-set-attr _el-button "_" "on click set trackingcode to `AB123456789KK` then set pdfurl to `https:")
+      (dom-set-attr _el-button "_" "on click set trackingcode to `AB123456789KK` then set pdfurl to `https://yyy.xxxxxx.com/path/out/${trackingcode}.pdf` then put pdfurl into me")
       (dom-append (dom-body) _el-button)
       (hs-activate! _el-button)
       (dom-dispatch _el-button "click" nil)
@@ -11019,7 +11019,7 @@
   (deftest "handles set url regression properly"
     (hs-cleanup!)
     (let ((_el-div (dom-create-element "div")))
-      (dom-set-attr _el-div "_" "on click set trackingcode to `foo` then set pdfurl to `https:")
+      (dom-set-attr _el-div "_" "on click set trackingcode to `foo` then set pdfurl to `https://yyy.xxxxxx.com/path/out/${trackingcode}.pdf` then put pdfurl into me")
       (dom-set-inner-html _el-div "lolwat")
       (dom-append (dom-body) _el-div)
       (hs-activate! _el-div)

tests/playwright/generate-sx-tests.py

@@ -1177,6 +1177,45 @@ def parse_dev_body(body, elements, var_names):
 
 # ── Test generation ───────────────────────────────────────────────
 
+def _strip_hs_line_comments(s):
+    """Strip `//…` and `--…` line comments outside HS string literals.
+
+    HS has three string delimiters: single quotes, double quotes, and
+    backticks (template strings). `https://…` inside a backtick must not
+    be treated as a comment.
+    """
+    out = []
+    i = 0
+    n = len(s)
+    in_str = None  # None | "'" | '"' | '`'
+    while i < n:
+        ch = s[i]
+        if in_str is None:
+            # Check for line-comment starters at depth 0.
+            if ch == '/' and i + 1 < n and s[i + 1] == '/':
+                # Skip to newline.
+                while i < n and s[i] != '\n':
+                    i += 1
+                continue
+            if ch == '-' and i + 1 < n and s[i + 1] == '-' and (i == 0 or s[i - 1].isspace()):
+                while i < n and s[i] != '\n':
+                    i += 1
+                continue
+            if ch in ("'", '"', '`'):
+                in_str = ch
+            out.append(ch)
+            i += 1
+        else:
+            if ch == '\\' and i + 1 < n:
+                out.append(ch); out.append(s[i + 1]); i += 2
+                continue
+            if ch == in_str:
+                in_str = None
+            out.append(ch)
+            i += 1
+    return ''.join(out)
+
+
 def process_hs_val(hs_val):
     """Process a raw HS attribute value: collapse whitespace, insert 'then' separators."""
     # Convert escaped newlines/tabs to real whitespace
@@ -1187,8 +1226,8 @@ def process_hs_val(hs_val):
     hs_val = hs_val.replace('\x00QUOT\x00', '\\"')
     # Strip line comments BEFORE newline collapse — once newlines become `then`,
     # an unterminated `//` / ` --` comment would consume the rest of the input.
-    hs_val = re.sub(r'//[^\n]*', '', hs_val)
+    # String-aware: `https://…` inside a backtick template must not be stripped.
-    hs_val = re.sub(r'(^|\s)--[^\n]*', r'\1', hs_val)
+    hs_val = _strip_hs_line_comments(hs_val)
     cmd_kws = r'(?:set|put|get|add|remove|toggle|hide|show|if|repeat|for|wait|send|trigger|log|call|take|throw|return|append|tell|go|halt|settle|increment|decrement|fetch|make|install|measure|empty|reset|swap|default|morph|render|scroll|focus|select|pick|beep!)'
     hs_val = re.sub(r'\s{2,}(?=' + cmd_kws + r'\b)', ' then ', hs_val)
     hs_val = re.sub(r'\s*[\n\r]\s*', ' then ', hs_val)