Support LANGUAGE JAVASCRIPT clause for stored functions and procedures

[kyleconroy]

Summary

MySQL 9.0 added JavaScript stored programs: CREATE FUNCTION ... LANGUAGE JAVASCRIPT AS $$ ... $$ (and same for CREATE PROCEDURE). Marino does not recognise the LANGUAGE characteristic or the $$ ... $$ body delimiter.

MySQL version

Introduced in MySQL 9.0 (community parses the syntax; the language component itself ships in MySQL Enterprise / HeatWave).

Current state in marino

grep -in 'LANGUAGE JAVASCRIPT\|JAVASCRIPT' parser/parser.y parser/keywords.go returns no matches. The current routine-characteristics list does not accept LANGUAGE other than the SQL/2003-standard LANGUAGE SQL (if at all).

Example SQL

CREATE FUNCTION js_add(a INT, b INT) RETURNS INT
  LANGUAGE JAVASCRIPT
  DETERMINISTIC
  NO SQL
  AS $$
    return a + b;
  $$;

CREATE PROCEDURE js_log(IN msg VARCHAR(255))
  LANGUAGE JAVASCRIPT
  AS $$
    console.log(msg);
  $$;

The body delimiter can be any matching $tag$ ... $tag$ pair:

CREATE FUNCTION js_q(s VARCHAR(64)) RETURNS VARCHAR(128)
  LANGUAGE JAVASCRIPT
  DETERMINISTIC
  NO SQL
  AS $body$
    return "got: " + s.replace(/'/g, "''");
  $body$;

Validation

CREATE FUNCTION ... LANGUAGE JAVASCRIPT ... AS $$ ... $$; parses against MySQL 9.2.0 Community. (The community build returns ER_LANGUAGE_COMPONENT_NOT_AVAILABLE when the function is invoked; that is the runtime, not the parser, rejecting it.)

Notes for the implementer

• Add LANGUAGE (already a keyword in some grammars), JAVASCRIPT as keywords.
• Lexer changes: recognise $tag$ ... $tag$ dollar-quoted strings as the routine body when preceded by AS in a CREATE FUNCTION/PROCEDURE with LANGUAGE JAVASCRIPT. The opening tag may be empty ($$) or alphanumeric ($body$).
• Routine AST: add a Language characteristic (SQL / JAVASCRIPT) and a raw-body string for non-SQL bodies.
• Also enables PREPARE/EXECUTE of event DDL (preparable as of MySQL 9.0).
• Reference: https://dev.mysql.com/doc/refman/9.2/en/create-procedure.html