Function _Validate_WITH_Clause

src/ast/ast_validations.c:1399–1470

validate a WITH clause

// validate a WITH clause
static VISITOR_STRATEGY _Validate_WITH_Clause
(
	const cypher_astnode_t *n,  // ast-node
	bool start,                 // first traversal
	ast_visitor *visitor        // visitor
) {
	validations_ctx *vctx = AST_Visitor_GetContext(visitor);

	vctx->clause = cypher_astnode_type(n);

	if(_Validate_LIMIT_SKIP_Modifiers(cypher_ast_with_get_limit(n),
		cypher_ast_with_get_skip(n)) == AST_INVALID) {
		return VISITOR_BREAK;
	}

	// manually traverse children. order by and predicate should be aware of the
	// vars introduced in the with projections, but the projections should not
	for(uint i = 0; i < cypher_ast_with_nprojections(n); i++) {
		// visit the projection
		const cypher_astnode_t *proj = cypher_ast_with_get_projection(n, i);
		AST_Visitor_visit(proj, visitor);
		if(ErrorCtx_EncounteredError()) {
			return VISITOR_BREAK;
		}
	}

	// introduce WITH aliases to the bound vars context
	if(!_AST_GetWithAliases(n, vctx->defined_identifiers)) {
		return VISITOR_BREAK;
	}

	// visit predicate clause
	const cypher_astnode_t *predicate = cypher_ast_with_get_predicate(n);
	if(predicate) {
		AST_Visitor_visit(predicate, visitor);
		if(ErrorCtx_EncounteredError()) {
			return VISITOR_BREAK;
		}
	}

	// visit ORDER BY clause
	const cypher_astnode_t *order_by = cypher_ast_with_get_order_by(n);
	if(order_by) {
		AST_Visitor_visit(order_by, visitor);
		if(ErrorCtx_EncounteredError()) {
			return VISITOR_BREAK;
		}
	}

	// if one of the 'projections' is a star -> proceed with current env
	// otherwise build a new environment using the new column names (aliases)
	if(!cypher_ast_with_has_include_existing(n)) {
		// free old env, set new one
		raxFree(vctx->defined_identifiers);
		vctx->defined_identifiers = raxNew();

		// introduce the WITH aliases to the bound vars context
		for(uint i = 0; i < cypher_ast_with_nprojections(n); i++) {