Function _ValidateCallInitialWith

src/ast/ast_validations.c:1201–1251

validates a leading `WITH` clause of a subquery

// validates a leading `WITH` clause of a subquery
static bool _ValidateCallInitialWith
(
	const cypher_astnode_t *with_clause,  // `WITH` clause to validate
	validations_ctx *vctx            // validation context
) {
	bool found_simple = false;
	bool found_non_simple = false;

	for(uint i = 0; i < cypher_ast_with_nprojections(with_clause); i++) {
		const cypher_astnode_t *curr_proj =
			cypher_ast_with_get_projection(with_clause, i);
		const cypher_astnode_t *exp =
			cypher_ast_projection_get_expression(curr_proj);
		const cypher_astnode_type_t t = cypher_astnode_type(exp);

		if (t == CYPHER_AST_IDENTIFIER ) {
			const cypher_astnode_t *alias =
				cypher_ast_projection_get_alias(curr_proj);
			// if this is an internal representation of a variable, skip it
			if(alias != NULL && cypher_ast_identifier_get_name(alias)[0] == '@') {
				continue;
			}
			const char *identifier = cypher_ast_identifier_get_name(exp);
			int len = strlen(identifier);
			if(found_non_simple || alias != NULL) {
				return false;
			}
			found_simple = true;
		} else {
			// check that the import does not make reference to an outer scope
			// identifier. This is invalid:
			// 'WITH 1 AS a CALL {WITH a + 1 AS b RETURN b} RETURN b'
			if(found_simple ||
			   !_ValidateSubqueryFirstWithClauseIdentifiers(exp)) {
					return false;
			}
			found_non_simple = true;
		}
	}

	// order by, predicates, limit and skips are not valid
	if(cypher_ast_with_get_skip(with_clause)      != NULL ||
		cypher_ast_with_get_limit(with_clause)     != NULL ||
		cypher_ast_with_get_order_by(with_clause)  != NULL ||
		cypher_ast_with_get_predicate(with_clause) != NULL) {

		return false;
	}

	return true;
}

// validate a CALL {} (subquery) clause
static VISITOR_STRATEGY _Validate_call_subquery