Function _Validate_shortest_path

src/ast/ast_validations.c:866–917

validate a shortest-path expression

// validate a shortest-path expression
static VISITOR_STRATEGY _Validate_shortest_path
(
	const cypher_astnode_t *n,  // ast-node
	bool start,                 // first traversal
	ast_visitor *visitor        // visitor
) {
	validations_ctx *vctx = AST_Visitor_GetContext(visitor);
	if(!start) {
		return VISITOR_CONTINUE;
	}

	if(cypher_ast_shortest_path_is_single(n)) {
		const cypher_astnode_t *path = cypher_ast_shortest_path_get_path(n);
		int elements = cypher_ast_pattern_path_nelements(path);
		const cypher_astnode_t *start = cypher_ast_node_pattern_get_identifier(cypher_ast_pattern_path_get_element(path, 0));
		const cypher_astnode_t *end = cypher_ast_node_pattern_get_identifier(cypher_ast_pattern_path_get_element(path, elements - 1));
		if(start == NULL || end == NULL) {
			ErrorCtx_SetError("A shortestPath requires bound nodes");
			return VISITOR_BREAK;
		}
		const char *start_id = cypher_ast_identifier_get_name(start);
		const char *end_id = cypher_ast_identifier_get_name(end);
		if(raxFind(vctx->defined_identifiers, (unsigned char *)start_id, strlen(start_id)) == raxNotFound ||
			raxFind(vctx->defined_identifiers, (unsigned char *)end_id, strlen(end_id)) == raxNotFound) {
			ErrorCtx_SetError("A shortestPath requires bound nodes");
			return VISITOR_BREAK;
		}
		return VISITOR_RECURSE;
	} else {
		// MATCH (a), (b), p = allShortestPaths((a)-[*2..]->(b)) RETURN p
		// validate rel pattern range doesn't contains a minimum > 1
		const cypher_astnode_t **ranges = AST_GetTypedNodes(n, CYPHER_AST_RANGE);
		int range_count = array_len(ranges);
		for(int i = 0; i < range_count; i++) {
			long min_hops = 1;
			const cypher_astnode_t *r = ranges[i];
			const cypher_astnode_t *start = cypher_ast_range_get_start(r);
			if(start) min_hops = AST_ParseIntegerNode(start);
			if(min_hops != 1) {
				ErrorCtx_SetError("allShortestPaths(...) does not support a minimal length different from 1");
				break;
			}
		}
		array_free(ranges);
	}

	if(ErrorCtx_EncounteredError()) {
		return VISITOR_BREAK;
	}

	return VISITOR_RECURSE;
}

// validate a pattern-path expression
static VISITOR_STRATEGY _Validate_pattern_path