Lexical error with escaped parentheses

[Thomas Åkesson]

Hi,
We have come across a potentially incorrect lexical error with the following 
combination in the query:
 - Parentheses in the search term (tried both escaping and quoting)
 - Query parser within {}. Actual use-case is using !graph but clearer 
reproduction with something simple like !boost. 
 - Using AND before the {!something ...} query.

This query fails:
curl 
'http://localhost:8983/solr/demo/select?q=inStock:true+AND+%7B%21boost+b%3Dmanufacturedate_dt%7Dname%3Athe%2520%5C%28concept%5C%29.xml'
{
  "responseHeader":{
    "status":400,
    "QTime":1,
    "params":{
      "q":"inStock:true AND {!boost 
b=manufacturedate_dt}name:the%20\\(concept\\).xml"
    }
  },
  "error":{
    
"metadata":["error-class","org.apache.solr.common.SolrException","root-error-class","org.apache.solr.parser.TokenMgrError"],
    "msg":"org.apache.solr.search.SyntaxError: Cannot parse 
'name:the%20\\(concept\\': Lexical error at line 1, column 22.  Encountered: 
<EOF> (in lexical state 3)",
    "code":400
  }


Fails when quoted (no escaping needed?):
curl 
'http://localhost:8983/solr/demo/select?q=inStock:true+AND+%7B%21boost+b%3Dmanufacturedate_dt%7Dname%3A%22the%2520%28concept%29.xml%22'
{
  "responseHeader":{
    "status":400,
    "QTime":1,
    "params":{
      "q":"inStock:true AND {!boost 
b=manufacturedate_dt}name:\"the%20(concept).xml\""
    }
  },
  "error":{
    
"metadata":["error-class","org.apache.solr.common.SolrException","root-error-class","org.apache.solr.parser.TokenMgrError"],
    "msg":"org.apache.solr.search.SyntaxError: Cannot parse 
'name:\"the%20(concept': Lexical error at line 1, column 21.  Encountered: 
<EOF> after prefix \"\\\"the%20(concept\" (in lexical state 3)",
    "code":400
  }

Removing the closing parenthesis works:
curl 
'http://localhost:8983/solr/demo/select?q=inStock:true+AND+%7B%21boost+b%3Dmanufacturedate_dt%7Dname%3Athe%2520%5C%28concept.xml'

Removing the statement before works:
curl 
'http://localhost:8983/solr/demo/select?q=%7B%21boost+b%3Dmanufacturedate_dt%7Dname%3Athe%2520%5C%28concept%5C%29.xml'


Has anyone seen this issue before? Tested with 8.3 and 9.6.1.

Thanks in advance,
Thomas Å.