app/src/test/capabilities.test.ts

@@ -135,25 +135,150 @@ function importSpecs(file: string): string[] {
   ];
 }
 
-/** Best-effort removal of block/line comments and string/template literals, so the namespace-usage
- * scan below doesn't trip on the alias appearing in prose or as text data. Regex-based, not a real
- * parser — good enough for this test's purpose, not a general-purpose stripper. */
-function stripCommentsAndStrings(text: string): string {
-  return text
-    .replace(/\/\*[\s\S]*?\*\//g, "")
-    .replace(/\/\/.*$/gm, "")
-    .replace(/`(?:\\.|[^`\\])*`/g, "``")
-    .replace(/"(?:\\.|[^"\\])*"/g, '""')
-    .replace(/'(?:\\.|[^'\\])*'/g, "''");
+/** Scans a double- or single-quoted string starting at `text[start]` (the opening quote) and
+ * returns the index just past its closing quote, honoring backslash escapes. Throws (fail-closed)
+ * on an unterminated string rather than silently running to end-of-file. */
+function skipQuoted(text: string, start: number, file: string): number {
+  const quote = text[start];
+  let i = start + 1;
+  while (i < text.length) {
+    if (text[i] === "\\") {
+      i += 2;
+      continue;
+    }
+    if (text[i] === quote) return i + 1;
+    i++;
+  }
+  throw new Error(`${relative(srcDir, file)}: unterminated ${quote === '"' ? "double" : "single"}-quoted string`);
+}
+
+/** Scans a `${...}` substitution's contents starting right after the `${`, tracking nesting of
+ * `{`/`(`/`[` (and skipping over any string/template/comment inside) so an unrelated `}` doesn't
+ * end the substitution early. Returns the raw source text of the substitution (not including the
+ * closing `}`) and the index just past that `}`. Throws (fail-closed) if it runs off the end
+ * without finding a balancing `}` — an unparseable substitution is not silently ignored. */
+function scanSubstitution(text: string, start: number, file: string): { content: string; endIndex: number } {
+  let i = start;
+  let depth = 0;
+  while (i < text.length) {
+    const c = text[i];
+    if (c === "\\") {
+      i += 2;
+      continue;
+    }
+    if (c === '"' || c === "'") {
+      i = skipQuoted(text, i, file);
+      continue;
+    }
+    if (c === "`") {
+      i = maskTemplate(text, i, file).endIndex;
+      continue;
+    }
+    if (c === "/" && text[i + 1] === "*") {
+      const end = text.indexOf("*/", i + 2);
+      if (end === -1) throw new Error(`${relative(srcDir, file)}: unterminated block comment`);
+      i = end + 2;
+      continue;
+    }
+    if (c === "/" && text[i + 1] === "/") {
+      const end = text.indexOf("\n", i + 2);
+      i = end === -1 ? text.length : end;
+      continue;
+    }
+    if (c === "{" || c === "(" || c === "[") {
+      depth++;
+      i++;
+      continue;
+    }
+    if (c === ")" || c === "]") {
+      depth--;
+      i++;
+      continue;
+    }
+    if (c === "}") {
+      if (depth === 0) return { content: text.slice(start, i), endIndex: i + 1 };
+      depth--;
+      i++;
+      continue;
+    }
+    i++;
+  }
+  throw new Error(`${relative(srcDir, file)}: unterminated template substitution ("\${...}" never closes)`);
+}
+
+/** Masks a backtick template literal starting at `text[start]` (the opening backtick): literal
+ * template *text* is dropped, but every `${...}` substitution's source is kept — recursively
+ * stripped of its own comments/strings/nested templates via `stripCommentsAndStrings` — since a
+ * namespace alias referenced only inside a substitution is passed by reference to whatever
+ * consumes it (a tagged template hands each substitution to the tag function unstringified,
+ * exactly like `fn(alias)`) and must stay visible to the occurrence scan. Throws (fail-closed) on
+ * an unterminated template. */
+function maskTemplate(text: string, start: number, file: string): { result: string; endIndex: number } {
+  let i = start + 1;
+  let result = "";
+  while (i < text.length) {
+    const c = text[i];
+    if (c === "\\") {
+      i += 2;
+      continue;
+    }
+    if (c === "`") return { result, endIndex: i + 1 };
+    if (c === "$" && text[i + 1] === "{") {
+      const { content, endIndex } = scanSubstitution(text, i + 2, file);
+      result += ` ${stripCommentsAndStrings(content, file)} `;
+      i = endIndex;
+      continue;
+    }
+    i++;
+  }
+  throw new Error(`${relative(srcDir, file)}: unterminated template literal`);
+}
+
+/** Best-effort removal of block/line comments and string/template literal *text*, so the
+ * namespace-usage scan below doesn't trip on the alias appearing in prose or as string data — while
+ * keeping the source of any `${...}` template substitution intact, recursively, since that's live
+ * code that can reference the alias. A small hand-rolled scanner, not a full parser: good enough
+ * for this test's purpose. Throws (fail-closed) on anything it can't make sense of — an
+ * unterminated string, comment or template — rather than silently truncating. */
+function stripCommentsAndStrings(text: string, file: string): string {
+  let out = "";
+  let i = 0;
+  while (i < text.length) {
+    const c = text[i];
+    if (c === "/" && text[i + 1] === "*") {
+      const end = text.indexOf("*/", i + 2);
+      if (end === -1) throw new Error(`${relative(srcDir, file)}: unterminated block comment`);
+      i = end + 2;
+      continue;
+    }
+    if (c === "/" && text[i + 1] === "/") {
+      const end = text.indexOf("\n", i + 2);
+      i = end === -1 ? text.length : end;
+      continue;
+    }
+    if (c === '"' || c === "'") {
+      i = skipQuoted(text, i, file);
+      continue;
+    }
+    if (c === "`") {
+      const masked = maskTemplate(text, i, file);
+      out += masked.result;
+      i = masked.endIndex;
+      continue;
+    }
+    out += c;
+    i++;
+  }
+  return out;
 }
 
 /** Every occurrence of a namespace-imported alias, after its import line, must be a plain
- * `alias.identifier` member access — `fn(alias)`, `const y = alias`, `alias["name"]` and
- * `alias[expr]` all hand the whole namespace object somewhere this scan can't follow, which is
- * exactly the silent-smuggling shape this test exists to close. Any such occurrence is fail-closed
- * rather than silently accepted. */
+ * `alias.identifier` member access — `fn(alias)`, `const y = alias`, `alias["name"]`,
+ * `alias[expr]`, and a tagged-template substitution like `` tag`${alias}` `` all hand the whole
+ * namespace object somewhere this scan can't follow, which is exactly the silent-smuggling shape
+ * this test exists to close. Any such occurrence is fail-closed rather than silently accepted. */
 function assertNamespaceUsedAsMemberAccessOnly(file: string, text: string, alias: string, importEnd: number) {
-  const rest = stripCommentsAndStrings(text.slice(importEnd));
+  const rest = stripCommentsAndStrings(text.slice(importEnd), file);
   const occurrence = new RegExp(`\\b${alias}\\b(\\.[A-Za-z_$][\\w$]*)?`, "g");
   for (const m of rest.matchAll(occurrence)) {
     if (!m[1]) {