Function removeClassByPattern

packages/cli/src/batch-transform.ts:886–923

* Remove all classes matching a regex pattern from a JSX element's className. * Handles StringLiteral, Literal, TemplateLiteral, and CallExpression className forms.

(nodePath: any, pattern: RegExp)

 * Handles StringLiteral, Literal, TemplateLiteral, and CallExpression className forms.
 */
function removeClassByPattern(nodePath: any, pattern: RegExp): void {
  const openingElement = nodePath.node.openingElement;
  const attrs = openingElement?.attributes ?? [];
  const classNameAttr = attrs.find(
    (a: any) => a.type === "JSXAttribute" && a.name?.name === "className"
  );
  if (!classNameAttr?.value) return;

  const val = classNameAttr.value;

  const removeFromStr = (s: string) =>
    s.split(/\s+/).filter((c: string) => c && !pattern.test(c)).join(" ");

  if (val.type === "StringLiteral" || val.type === "Literal") {
    val.value = removeFromStr(val.value);
    return;
  }
  if (val.type === "JSXExpressionContainer") {
    const expr = val.expression;
    if (expr.type === "TemplateLiteral") {
      for (const quasi of expr.quasis ?? []) {
        const raw = quasi.value.raw;
        const leadingWs = raw.match(/^(\s*)/)?.[1] ?? "";
        const trailingWs = raw.match(/(\s*)$/)?.[1] ?? "";
        const cleaned = removeFromStr(raw.trim());
        quasi.value = { raw: `${leadingWs}${cleaned}${trailingWs}`, cooked: `${leadingWs}${cleaned}${trailingWs}` };
      }
      return;
    }
    if (expr.type === "CallExpression") {
      for (const arg of expr.arguments ?? []) {
        if (arg.type === "StringLiteral" || arg.type === "Literal") {
          arg.value = removeFromStr(arg.value ?? "");
        }
      }
    }
  }
}

/** Default Tailwind spacing scale: token → px. Used by the batch engine to
 *  read back existing translate classes and accumulate deltas. */